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A  STANDARD  FOR 

TRITIUM 


A  recommendation 

to  the  Minister 

of  the 

Environment  and  Energy 


AŒS 

Advisory 

Committee 

on  Environmental 

Standards 


Comité 

consultatif 

sur  les  normes 

environnmentales 


A  STANDARD  FOR 

TRITIUM 


A  recommendation 

to  the  Minister 

of  the 

Environment  and  Energy 


ACES  Report  94-01 

May,  1994 

ISBN:  0-7778-2979-7 


Executive  Summary 

On  December  16,  1993,  The  Honourable  C.J.  (Bud)  Wildman,  Minister  of  the 
Environment  and  Energy,  wrote  to  the  Advisory  Committee  on  Environmental 
Standards  (ACES)  and  requested  that  ACES  conduct  a  public  consultation  on  the 
Ministry's  proposed  Interim  Ontario  Drinking  Water  Objective  (ODWO)  for  tritium  of 
7,000  Becquerels  per  litre  (Bq/L).    This  referral  arose  as  a  result  of  public  concern 
about  a  plan  to  expand  the  existing  water  supply  plant  in  Ajax,  Ontario.    This  plant 
would  draw  raw  water  from  Lake  Ontario  and  is  adjacent  to  the  Pickering  Nuclear 
Power  Generating  Station  (PNGS),  which  discharges  tritium  in  waste  water  into  the 
lake. 

Tritium  is  a  radioactive  form  of  hydrogen.    It  is  long  lasting,  with  a  radioactive  half- 
life  of  12.3  years  and  a  biological  half-iife  of  10  days  to  2  years.    Tritium  occurs 
naturally,  but  the  majority  of  tritium  in  Lake  Ontario  is  a  byproduct  of  CANDU 
nuclear  reactor  operations.    Conventional  water  treatment  is  not  able  to  remove  tritium 
from  drinking  water  as  it  passes  through  the  water  treatment  plant.    The  only  practical 
way  to  reduce  tritium  levels  entering  surface  waters  drawn  by  water  treatment  plants  is 
to  reduce  emissions  from  CANDU  nuclear  facilities. 

ACES  invited  public  comment  on  the  proposed  ODWO  by  using  a  large  mailing  list 
and  by  advertising  in  newspapers.    Respondents  were  sent  a  copy  of  the  Ministry's 
Rationale  Document  for  the  Development  of  an  Interim  Ontario  Drinking  Water 
Objective  for  Tritium  (MOEE  1993)  and  were  asked  to  comment  on  it.    Public  interest 
in  this  issue  was  widespread  and  resulted  in  new  information  not  contained  in  the 
Rationale  Document  being  brought  to  the  attention  of  ACES.    For  example,  ACES 
learned  that  readers  of  the  Rationale  Document  would  probably  underestimate  the  fatal 
cancer  risk  posed  by  the  proposed  ODWO.    The  Ontario  Ministry  of  the  Environment 
and  Energy's  (MOEE)  policy  on  Drinking  Water  Objectives  states  that  lifelong 
exposure  (estimated  to  be  70  years)  must  be  considered.    The  documents  used  in 
deriving  the  ODWO  for  tritium,  however,  consider  exposure  for  only  one  year. 
Although  this  approach  has  often  been  taken  by  nuclear  regulatory  agencies,  it  is 
clearly  at  odds  with  MOEE' s  policy  on  drinking  water  guidelines.  Exposure  to  7,000 
Bq/L  represents  a  risk  of  approximately  340  excess  fatal  cancers  per  million  people 
exposed  over  their  entire  lives. 

In  many  regulatory  agencies,  including  MOEE,  1  excess  cancer  per  million  people 
exposed  is  often  considered  acceptable  if  there  are  multiple  media  for  exposure  to  a 
given  contaminant  and  a  large  population  is  affected.  A  higher  level  of  acceptable  risk 
of  1  excess  cancer  per  hundred  thousand  people  exposed  is  often  used  to  derive 
standards  when  small  populations  are  affected,  and  their  exposure  results  from  only  a 
single  medium.  Exposure  to  tritium  in  Ontario  occurs  through  drinking  water  and  the 
affected  population  may  be  large.  Exposure  may  also  occur  via  air  and  perhaps,  food. 
Therefore,  ACES  recommends  that  an  acceptable  level  of  risk  for  excess  cancers  due 
to  exposure  to  tritium  be  5  per  million  people  at  risk,  as  suggested  by  the  MOEE  in 
the  Rationale  document.  Given  a  70  year  (lifelong)  exposure,  and  assuming  the  annual 


risk  is  additive,  this  would  result  in  an  Ontario  Drinking  Water  Objective  of  100 
Bq/L. 

There  are  many  other  sources  of  uncertainty  and  concern  which  were  brought  to  the 
attention  of  ACES  by  members  of  the  public  during  this  consultation.    For  example, 
the  risk  calculations  do  not  directly  address  non-fatal  cancers  nor  health  effects  other 
than  cancer,  and  there  is  scientific  uncertainty  regarding  the  relative  biological 
effectiveness  of  tritium.  Some  members  of  the  public  also  expressed  concern  that  the 
most  sensitive  subpopulation  (the  developing  fetus)  was  not  considered  in  the  risk 
calculation.  For  these  reasons,  ACES  recommends  that  the  ODWO  for  tritium  be 
reduced  over  time  to  20  Bq/L,  corresponding  to  an  acceptable  level  of  risk  of  1  excess 
cancer  per  million  people  following  lifelong  exposure.  Several  members  of  the  public 
pointed  out  that  tritium  would  meet  the  International  Joint  Commission's  (DC) 
definition  of  a  persistent  toxic  substance  and,  on  that  basis,  should  be  virtually 
eliminated  from  industrial  discharges.  Some  respondents  pointed  out  that  on  the  basis 
of  the  IJC's  recent  Seventh  Biennial  report,  tritium  should  be  considered  a  candidate 
for  "zero  discharge".   Others  suggested  that  tritium  be  added  to  Ontario's  Priority 
Pollutants  List  as  it  is  a  known  carcinogen  which  is  discharged  into  Provincial  surface 
waters.  ACES  endorses  these  principles  and  recommends  that  discussions  should  be 
initiated  with  Ontario  Hydro  and  AECL  regarding  the  feasibility  of  reducing  tritium 
emission  levels  from  nuclear  facilities  in  Ontario. 

ACES  consulted  the  public  on  the  proposed  Interim  ODWO  of  7,000  Bq/L  and  the 
feasibility  of  achieving  this  level.  ACES  is  not  aware  of  comprehensive  information  on 
the  feasibility  of  achieving  the  lower  recommended  level  of  100  Bq/L,  nor  was  this 
issue  addressed  in  the  MOEE's  Rationale  Document.  However,  the  monitoring  data 
available  through  the  Ministry's  Drinking  Water  Surveillance  Program  (DWSP) 
suggest  that  100  Bq/L  is  rarely  exceeded.    Therefore,  it  is  a  currently  achievable 
standard  which  will  only  become  more  readily  achievable  as  background  levels  of 
tritium  decline  due  to  the  decay  of  nuclear  fallout  from  atmospheric  weapons  testing. 

The  same  monitoring  data  indicate  that  20  Bq/L  is  not  currently  a  routinely  achievable 
standard  in  drinking  water  near  nuclear  facilities.    Because  conventional  water 
treatment  does  not  remove  tritium,  ACES  recommends  that  feasibility  studies  be 
undertaken  with  the  goal  of  reducing  tritium  emissions  sufficiently  to  permit  the 
ODWO  to  be  lowered  to  20  Bq/L  within  5  years. 

In  conclusion,  ACES  recommends  that  the  Ontario  Drinking  Water  Objective  for 
Tritium  be  set  immediately  at  100  Bq/L.  ACES  further  recommends  that,  due  to  the 
fact  that  tritium  is  a  human  carcinogen  and  because  of  the  many  uncertainties  in  the 
risk  assessment,  the  tolerable  level  of  tritium  in  drinking  water  be  reduced  to  20  Bq/L 
in  5  years  with  the  goal  of  further  reduction  as  human  contributions  to  tritium 
background  levels  decline.  The  five  year  schedule  for  the  reduction  acknowledges  the 
need  for  technical  and  financial  feasibility  studies  on  the  ODWO  of  20  Bq/L.    In 
addition,  ACES  recommends  that  this  standard  be  applied  as  a  health-based  Maximum 
Acceptable  Concentration,  so  that  when  the  drinking  water  standard  is  exceeded,  an 
alternative  water  supply  should  be  made  available. 


Table  of  Contents  Pa8e 

Executive  Summary  • 

Referral  1 

Recommendation  for  an  Interim 

Ontario  Drinking  Water  Objective 

for  Tritium  * 

List  of  Acronyms  2 

Glossary  4 

Background 

Public  Health  Significance  8 

What  is  Tritium?  8 

Sources  of  Exposure  to  Tritium  8 
Routes  of  Exposure 

Exposure  Pathways  9 

Adverse  Health  Effects  of  Tritium  10 

The  Tritium  Challenge  1° 

Internal  Review  H 

Public  Consultation  Process  12 

Review  of  Public  Comment  I4 

Overview  of  Public  Response  15 

Exposure  1° 

Risk  17 

Feasibility 

Implementation  23 

Need  for  Additional  Studies  26 

Other  Comments  and  Recommendations  27 

Summary  of  Recommendations  28 


References 


30 


Appendices 

1  Background  Material  on  Tritium  32 

2  List  of  Respondents  in  ACES' s  Public  Consultation  on  Tritium  39 

3  Summary  Tables  of  Public  Comments  43 

4  Letter  from  Dr.  Waight,  Health  Canada  85 

5  U.S.  EPA's  Science  Advisory  Board  paper  entitled 
Harmonizing  Chemical  and  Radiation  Risk  Reduction 

Strategies-A  Science  Advisory  Board  Commentary  87 

6  Table  2:   The  Effect  of  Various  Issues  on  the  Recommended 

ODWO  101 

7  1991  Tritium  Data  from  the  Nuclear  Surveillance  Program  and 

Analysis  of  Tritium  in  Drinking  Water  102 


Referral 


On  December  16,  1993,  the  Honourable  C.J.  (Bud)  Wildman,  Minister  of  the 
Environment  and  Energy,  requested  that  the  Advisory  Committee  on  Environmental 
Standards  (ACES)  consult  with  the  public  on  the  Ministry  of  the  Environment  and 
Energy's  proposed  Interim  Ontario  Drinking  Water  Objective  (ODWO)  of  7,000 
Becquerels  per  litre  (Bq/L)  for  the  radionuclide  tritium  in  drinking  water.    ACES  was 
requested  to  review  and  provide  recommendations  on  the  proposed  Interim  Ontario 
Drinking  Water  Objective. 


Recommendation 
for  an  Interim 
Ontario 

Drinking  Water 
Objective  for 
Tritium 

ACES  recommends  that  the  Ontario  Drinking  Water  Objective  for  Tritium  be  set 
immediately  at  100  Bq/L.  ACES  further  recommends  that,  due  to  the  fact  that  tritium 
is  a  human  carcinogen  and  because  of  the  many  uncertainties  in  the  risk  assessment, 
the  tolerable  level  of  tritium  in  drinking  water  be  reduced  to  20  Bq/L  in  5  years  with 
the  goal  of  further  reduction  as  human  contributions  to  tritium  background  levels 
decline.  The  five  year  schedule  for  the  reduction  acknowledges  the  need  for  technical 
and  financial  feasibility  studies  on  the  ODWO  of  20  Bq/L.    In  addition,  ACES 
recommends  that  this  standard  be  applied  as  a  health-based  Maximum  Acceptable 
Concentration,  so  that  when  this  drinking  water  standard  is  exceeded,  an  alternative 
water  supply  should  be  made  available. 


List  of  Acronyms 

ACES  Advisory  Committee  on  Environmental  Standards 

Atomic  Energy  Control  Board 
Atomic  Energy  of  Canada  Limited 


AECB 
AECL 
BEIR 


The  U.S.  National  Research  Council's  Committee  on  Biological  Effects  of 
Ionizing  Radiation 


Bq  Becquerel 

CDWG  Canadian  Drinking  Water  Guidelines 

CANDU  CANadian  Deuterium  Uranium  (the  type  of  nuclear  reactors  used  in  Canada) 

DWSP  Drinking  Water  Surveillance  Program 

EAAC  Environmental  Assessment  Advisory  Committee 

*H  Tritium  (Hydrogen  3) 

DEL  Derived  Emission  Limit 

ICRP  International  Commission  on  Radiological  Protection 

UC  International  Joint  Commission 

MAC  Maximum  Acceptable  Concentration 

MOEE  Ministry  of  the  Environment  and  Energy 

MOL  Ministry  of  Labour 

mSv  Millisievert 

NCRP  National  Council  on  Radiation  Protection  and  Measurements  (US) 

NGS  Nuclear  Generating  Station 

ODWO  Ontario  Drinking  Water  Objectives 

OWRA  Ontario  Water  Resources  Act 


OBT  Organically  Bound  Tritium 

RBE  Relative  Biological  Effectiveness 

UNSCEAR  United  Nations  Scientific  Committee  on  the  Effects  of  Atomic  Radiation 

U.S.  EPA  United  States  Environmental  Protection  Agency 

WHO  World  Health  Organization 

WSP  Water  Supply  Plant 


Glossary 

Activity: 

The  rate  of  decay  (i.e.  number  of  disintegrations  or  transformations  per  unit  time)  of  a 
radioactive  nuclide.  The  international  unit  of  activity  is  the  becquerel  (Bq). 

Background  Radiation: 

The  amount  of  radiation  to  which  a  member  of  the  population  is  exposed  from  natural 
sources  including  terrestrial  radiation  due  to  naturally  occurring  radionuclides  in  the 
soil  and  cosmic  radiation  originating  in  outer  space.    The  main  contributing  factor  to 
what  is  now  referred  to  as  "background"  tritium  levels  is  fallout  from  atmospheric 
nuclear  weapons  testing. 

Beta  Particles: 

Fast  moving  electrons  ejected  from  the  nuclei  of  certain  unstable  radioactive  atoms 
(e.g.  tritium).  Beta  particles  are  not  densely  ionizing. 

Becquerel  (Bq): 

International  unit  of  measurement  of  the  activity  of  a  radioactive  nuclide.  One 
becquerel  corresponds  to  one  atomic  transformation  or  disintegration  per  second  and  is 
equivalent  to  2.7  x  10""  Curies. 

Carcinogen: 

An  agent  that  can  cause  cancer.  Ionizing  radiation  is  a  carcinogen.    Tritium,  which 
emits  ionizing  radiation,  is  a  carcinogen. 

Committed  Effective  Dose: 

The  effective  dose  that  will  be  accumulated  over  70  years  following  a  single  intake  of 
radioactive  material  into  the  body. 

Curie  (Ci): 

A  unit  of  activity  equal  to  3.7  x  1010  disintegrations  per  second. 


Dose  Equivalent: 

A  measurement  that  relates  absorbed  dose  with  the  biological  effectiveness  (i.e. 
probability  of  causing  biological  damage)  of  various  kinds  of  ionizing  radiation.  Dose 
equivalents  are  calculated  by  multiplying  the  absorbed  dose  by  a  quality  factor  that 
accounts  for  differences  between  different  types  of  radiation.  The  international  unit  of 
dose  equivalents  is  the  sievert  (Sv). 


Gray: 

The  SI  unit  of  absorbed  dose  where  one  gray  equals  one  joule  per  kilogram,  and  one 
gray  equals  100  rad. 

Half-Life: 

The  time  taken  for  the  activity  of  a  radionuclide  to  lose  half  its  value  by  decay. 

Ionizing  Radiation: 

Radiation  that  is  capable  of  producing  ions  (particles  with  an  electric  charge)  by 
dislodging  electrons  from  an  atom. 

Maximum  Acceptable  Concentration  (MAC): 

A  MAC  is  a  type  of  Drinking  Water  Objective  that  is  established  for  certain 
substances  that  are  known  or  suspected  to  cause  adverse  effects  on  health.  Each  MAC 
has  been  derived  to  safeguard  health  assuming  lifelong  consumption  of  drinking  water 
containing  the  substance  at  that  concentration. 

Multimedia: 

A  multimedia  assessment  considers  how  a  contaminant  released  to  one  medium  (air, 
water,  soil  or  sediment)  may  move  to  or  impact  other  media.  This  approach  also 
considers  all  human  exposure  routes  including  food,  water,  air  and  soil. 

Organically  Bound  Tritium  (OBT): 

Tritium  is  bound  organically  either  in  exchange  reactions  or  into  stable  bonds  to 
carbon  atoms  only  via  enzymatically  catalyzed  reactions  in  which  it  replaces  hydrogen. 
Tritiated  organic  matter  is  classified  as  a  function  of  the  fractions  of  the  exchangeable 
and  non-exchangeable  bound  tritium  it  contains,  e.g.  organic  compounds  that 
incorporate  radioactive  tritium  in  place  of  hydrogen,  vegetable  food  and  animal  foods 
around  Nuclear  Generating  Stations  have  higher  OBT  concentrations. 

Rad: 

A  unit  of  absorbed  dose,  now  replaced  in  international  units  by  the  gray,  where  one 
rad  equals  0.01  gray. 

Radioactivity: 

The  spontaneous  emission  of  radiation,  in  the  form  of  alpha  particles,  beta  particles, 
etc. 

Radionuclide: 

An  unstable  nuclide  that  emits  ionizing  radiation 

Relative  Biological  Effectiveness  (RBE): 

The  biological  potency  of  one  type  of  radiation  as  compared  with  another  to  produce 
equivalent  biological  damage. 


Rem: 

A  measure  of  dose  equivalent  (1  rem  =  0.01  Sv). 

Standard: 

The  term  "standard"    in  this  report  includes  interim  standards,  objectives,  guidelines, 
and  any  other  form  of  limitation  which  specify  a  tolerable  level  for  environmental 
contaminants. 

Sievert: 

The  SI  unit  of  measure  defined  as  the  quantity  of  absorbed  radiation  that  induces  the 
same  biological  effect  in  a  specified  tissue  as  1  gray  of  high-energy  x-rays;  1  sievert 
=  100  rem  or  1000  millisieverts.  A  sievert  is  used  as  an  international  unit  of  dose 
equivalents.  The  quantity  is  obtained  by  multiplying  the  dose  equivalents  to  various 
tissues  and  organs  by  the  risk  weighting  factor  appropriate  to  each  organ  and  summing 
the  products. 


Background 


In  1990  the  Region  of  Durham  approved  a  recommendation  to  enlarge  the  existing 
water  supply  plant  in  Ajax  to  address  the  need  for  additional  water  supplies. 

In  1992  the  Minister  of  the  Environment  at  the  time,  Ruth  Grier,  asked  the 
Environmental  Assessment  Advisory  Committee  (EAAC)  for  advice  on  whether  an 
individual  environmental  assessment  should  be  required  for  the  proposed  water  supply 
plant. 

In  its  report  to  the  Minister,  the  EAAC  recommended  against  an  individual 
environmental  assessment  for  the  proposed  plant  provided  that  certain 
recommendations  were  appropriately  addressed. 

With  respect  to  concerns  raised  about  tritium  concentrations  in  drinking  water  due  to 
the  water  supply  plant's  close  proximity  to  the  Pickering  Nuclear  Generating  Station, 
EAAC  recommended  that  the  Minister  request  that  the  Advisory  Committee  on 
Environmental  Standards  (ACES)  carry  out  a  public  review  and  advise  the  Minister  on 
an  appropriate  standard  for  tritium  in  drinking  water. 

The  Ministry  of  the  Environment  and  Energy's  Standards  Development  Branch 
produced  the  Rationale  Document  for  the  Development  of  an  Interim  Ontario  Drinking 
Water  Objective  for  Tritium  (MOEE  1993).     The  Minister  then  requested  that  ACES 
carry  out  a  public  consultation  on  the  Interim  ODWO  for  tritium  proposed  in  the 
Rationale  Document. 


Public  Health 
Significance 


What  is 
Tritium? 


Tritium  is  a  radioactive  isotope  of  hydrogen.   It  has  a  half-life  of  12.3  years  (the 
amount  of  time  it  takes  one  half  of  a  quantity  of  tritium  to  decay  into  non-radioactive 
helium).    The  biological  half-life  of  tritium  (the  amount  of  time  the  body  requires  to 
excrete  one  half  of  the  tritium  absorbed)  ranges  between  10  days  and  two  years, 
depending  on  its  location  in  the  body. 

Tritium  is  a  by-product  of  Canadian  Deuterium  Uranium  (CANDU)  nuclear  reactor 
operations  and  it  also  occurs  naturally.    Tritium  is  produced  in  CANDU  reactors 
through  the  absorption  of  a  neutron  into  a  deuterium  atom  in  heavy  water,  which  is 
used  as  a  moderator  and  coolant.    During  reactor  operation,  a  small  fraction  of  the 
deuterium  molecules  in  the  heavy  water  take  on  an  additional  neutron  and  thus  they 
become  radioactive  tritium  (3H).    The  resulting  tritiated  water  is  regularly  discharged 
from  these  reactors.    Radioactive  tritium*   (3H)  decays  to  non-radioactive  helium  (3He) 
and  emits  a  negatively  charged  beta  particle  (P~). 

The  decay  formula  is  as  follows: 

^  ->  ^e   +    p" 

This  weak  beta-emitter  is  used  commercially  as  a  light  source  in  flares,  emergency 
lights,  exit  signs,  and  luminous  dials.    It  also  has  uses  in  medical  research.    As  well  as 
being  an  essential  fuel  for  nuclear  fusion,  tritium  can  be  used  in  nuclear  weapons 
production. 


Sources  of 
Exposure  to 
Tritium 


Today,  the  main  source  of  tritium  released  into  the  Canadian  environment  in  air  and 
water  emissions  is  nuclear  energy  production  facilities.  In  particular,  the  CANDU  type 
water-cooled  reactors  used  by  Ontario  Hydro,  representing  the  largest  Canadian  point 
source  of  tritium,  release  tritium  both  operationally  and  accidentally. 


"When  "tritium"  is  used  in  this  report  it  refers  to  tritiated  water,  unless  otherwise 
specified. 


The  majority  of  tritium  exposure  is  the  result  of  human  activities.    Tritium  is  produced 
in  nuclear  explosions.   Fallout  from  thermonuclear  weapons  testing,  begun  in  the 
1940s,  is  a  source  of  tritium  in  the  global  environment.    A  very  large  quantity  of 
tritium  has  been  released  from  these  activities,  resulting  in  a  sharp  increase  in  the 
tritium  content  of  rain  water  and  atmospheric  tritium.    This  was  the  main  contributing 
factor  to  a  rise  in  what  is  now  referred  to  as  "background"  tritium  levels.    In  recent 
years  background  levels  of  tritium  have  declined,  reflecting  the  cessation  of 
atmospheric  nuclear  testing  and  the  decay  of  tritium  over  time  from  these  explosions. 

In  nature,  tritium  is  produced  by  the  interaction  of  cosmic  rays  with  molecules  of 
nitrogen,  oxygen  and  argon  in  the  upper  atmosphere.    It  is  converted  into  tritiated 
water  and  precipitated  into  the  global  water  cycle.    Natural  sources  of  tritium  account 
for  less  than  1  %  of  tritium  exposure. 


Routes 

of 

Exposure 


Once  released  to  the  environment,  tritium  exposure  to  humans  can  occur  from  a 
variety  of  routes,  namely  via  water,  air,  and  food.    Exposure  to  water-borne  releases 
can  occur  through  the  consumption  of  drinking  water  supplies  or  through  other  water 
contact,  e.g.,  swimming,  bathing,  showering,  etc. 

Air-borne  tritium  is  also  a  source  of  exposure  to  communities  around  nuclear 
generating  stations.    Air-borne  releases  of  tritium  contaminate  ambient  air  and  can 
settle  on  surface  waters  and  agricultural  lands. 


Exposure 
Pathways 


Tritium  can  be  taken  into  the  body  by  inhalation,  absorption  through  the  skin,  or 
ingestion.    Tritium  entering  the  body  by  inhalation  is  normally  distributed  uniformly 
among  all  the  soft  tissues  in  the  body. 

The  absorption  of  tritiated  water  through  the  skin  is  a  pathway  of  human  exposure. 
Bathing,  showering  or  recreational  activities  are  examples  of  human  dermal  exposure 
routes. 


Following  ingestion,  tritiated  water  is  absorbed  immediately  from  the  gastrointestinal 
tract  and  then  mixes  rapidly  with  the  total  body  water.    In  addition,  ingestion  of 
contaminated  foods  is  a  potential  exposure  pathway  from  air-borne  tritium  emissions. 
The  ingestion  of  contaminated  fruits,  vegetables  or  food  animal  products  raised  near 
nuclear  generating  stations  may  be  a  significant  source  of  organically  bound  tritium 
(OBT),  i.e.,  organic  compounds  that  incorporate  radioactive  tritium  in  place  of  normal 
hydrogen. 


Adverse 
Health 
Effects  of 
Tritium 


Tritium  is  classified  as  a  human  carcinogen  by  the  United  States  Environmental 
Protection  Agency.    There  is  no  safe  exposure  level  for  any  form  of  ionizing 
radiation.    Low  doses  of  radiation  are  known  to  cause  genetic  damage  in  living  cells. 
Where  reproductive  cells  are  affected  by  radiation,  mutations  may  occur  and  adverse 
effects  may  manifest  in  offspring. 

Exposure  to  radiation  may  also  result  in  the  development  of  cancer.    A  cancer  may 
occur  at  any  dose  of  ionizing  radiation. 


The 

Tritium 

Challenge 


The  connection  between  tritium  emissions  from  nuclear  facilities  and  tritium  levels  in 
drinking  water  is  critical.    Levels  of  tritium  in  drinking  water  in  excess  of  background 
are  the  result  of  emissions  from  nuclear  facilities.    Ontario  Hydro,  in  their  report 
entitled  "Annual  Summary  and  Assessment  of  Environmental  Radiological  Data  for 
1991",  state  that  "Tritium  concentrations  in  drinking  water  taken  from  Lake  Ontario  at 
the  Ajax,  Whitby,  Oshawa,  Scarborough  and  Toronto  (Harris)  plants  exceeded  the 
Lake  Ontario  average  of  8.7  Bq/L  due  to  emissions  to  water  at  the  Pickering 
generating  stations."     Conventional  water  treatment  is  unable  to  remove  tritium  from 
drinking  water  supplies.    Therefore,  significant  reductions  in  tritium  levels  in  surface 
waters,  which  are  a  drinking  water  source,  can  only  be  achieved  by  additional 
emission  controls  at  nuclear  facilities. 


10 


Internal 
Review 


Upon  receipt  of  the  Rationale  Document  from  the  Ministry,  ACES  undertook  its  own 
internal  review.    ACES  concluded  that  the  material  presented  in  the  Rationale 
Document  (MOEE  1993)  was  adequate  to  proceed  with  public  consultation,  but  ACES 
noted  the  absence  of  a  scientific  criteria  document.    ACES  requested  that  the  key 
references  used  in  the  development  of  the  Rationale  Document  be  compiled  by  the 
MOEE,  and  these  documents  were  provided  by  ACES  for  public  review  during  the 
consultation. 


11 


Public 

Consultation 

Process 


ACES  undertook  a  public  consultation  on  a  drinking  water  standard  for  tritium  which 
involved  several  methods  of  reaching  out  to  the  interested  public.    These  included 
mailing  a  consultation  package  to  ACES' s  general  mailing  list,  advertising  in 
newspapers  and  magazines  and  holding  public  information  meetings  in  the 
Ajax/Pickering  area.    ACES' s  general  mailing  list  was  compiled  from  several  mailing 
lists  provided  by  the  Ministry  of  the  Environment  and  from  individuals  or 
organizations  who  had  expressed  interest  in  ACES' s  previous  consultations.    A 
targeted  list  composed  of  additional  groups  who  were  thought  to  have  a  particular 
interest  in  this  consultation  was  generated.    They  included:  industrial  groups, 
environmental  organizations,  labour  unions,  and  Ajax/Pickering  area  residents/groups. 

A  package  of  background  material  (see  Appendix  1)  was  prepared  including: 
-a  cover  letter  describing  the  consultation; 

-a  copy  of  the  advertisement  that  appeared  in  newspapers  (which  included  the 
questions  being  posed); 

-a  list  of  the  background  documents  used  in  the  development  of  the  proposed 
tritium  standard  and  their  locations  for  review; 

-a  copy  of  the  News  Release  describing  the  referral  of  the  tritium  standard  to 
ACES; 

-a  "Backgrounder"  on  tritium  prepared  by  the  Ministry  of  the  Environment  and 
Energy; 

-information  on  the  concurrent  ACES  public  consultation  on  the  proposed 
multimedia  standards  for  lead. 

Everyone  was  provided  with  a  postage  paid  return  envelope  to  encourage  participation. 
This  package  was  sent  to  approximately  6,600  people  between  January  10,  1994  and 
January  14,  1994. 

The  questions  posed  were  as  follows: 

1 .  Is  the  proposed  standard  acceptable? 

2.  If  not,  what  is  the  basis  for  finding  the  proposed  level  unacceptable? 

3.  Do  you  have  an  alternative  level  to  propose? 

Additional  comments  were  also  encouraged. 

A  second  mail  out  was  sent  to  330  individuals  and  organizations  who  had  been 
identified  as  having  a  special  interest  in  the  review  of  tritium  but  who  had  not 
responded  to  the  first  mail  out  after  28  days  had  elapsed. 


12 


In  order  to  reach  members  of  the  potentially  interested  public  who  might  not  be  on  the 
mailing  list,  an  advertisement,  which  included  the  above  questions,  appeared  once  in 
the  Globe  and  Mail  and  in  each  of  19  newspapers  in  communities  located  near  nuclear 
generating  stations  or  other  nuclear  facilities  during  the  week  of  January  10  to  January 
14,  1994.    An  advertisement  also  appeared  in  the  Ontario  Gazette  on  January  8,  1994 
and  on  the  Web  Network  on  January  10,  1994.    (The  Web  Network  is  a 
communication  network  to  which  many  different  organizations,  including  many 
environmental  groups  from  around  the  world,  subscribe.) 

A  package  of  supporting  documentation  was  made  available  for  review  at  the  ACES 
Office  in  Toronto  and  at  the  Town  of  Ajax  Clerk's  office  (see  page  2  of  Appendix  1). 

A  public  information  session  was  held  on  January  27,  1994  in  Ajax,  Ontario  in  order 
to  explain  ACES' s  public  consultation  process  and  to  allow  the  Ministry  of  the 
Environment  and  Energy  to  provide  the  rationale  for  the  development  of  the  standard. 
An  announcement  of  the  meeting  was  included  in  the  mail  out  packages  and  an 
advertisement  outlining  the  times  and  location  of  the  meeting  was  placed  in  4  Ajax 
area  newspapers.    In  order  to  make  the  meeting  as  accessible  as  possible  to  those  who 
wished  to  attend,  there  were  two  times  scheduled  for  this  meeting,  one  in  the 
afternoon  and  one  in  the  evening.   ACES  ensured  that  the  meeting  room  was  wheel 
chair  accessible  and  an  audio  technician  provided  amplification  to  the  participants  to 
facilitate  hearing.    A  summary  of  the  presentations  was  also  provided  in  poster  form 
outside  the  meeting  room.    These  meetings  were  tape  recorded  and  written  transcripts 
were  made  available  upon  request.   Approximately  100  copies  of  the  transcripts  were 
requested.    In  addition,  the  evening  session  of  the  meeting  was  video  taped  by 
MacLean  Hunter  Cable  television  and  aired  at  least  8  times  over  the  month  of 
February,  1994. 

Requests  for  oral  deputations  were  received  until  February  7,  1994.   A  deputation 
session  was  held  in  Pickering  on  February  16,  1994,  at  which  seven  presenters  made 
oral  submissions  to  ACES.    A  second  deputation  session  was  held  via  teleconference 
on  February  28,  1994,  in  which  four  presenters  participated.    This  was  the  first  time 
that  ACES  undertook  a  teleconference  deputation,  which  permitted  presenters  from 
across  the  Province  to  make  oral  presentations  to  the  Committee  without  travelling 
long  distances.    ACES  felt  that  the  consultation  on  the  proposed  Interim  ODWO  for 
tritium  was  effective  and  efficient,  in  part  as  a  result  of  the  combination  of  targeted 
advertisements  and  other  audio-visual  techniques. 

The  deadline  for  the  public  to  send  written  responses  on  the  proposed  ODWO  for 
tritium  was  March  10,  1994. 


13 


Review  of 

Public 

Comment 


A  total  of  226  requests  for  additional  information  were  received  in  response  to  the 
initial  mail  out  and  advertisements.    These  respondents  were  sent  the  Rationale 
Document  for  the  Development  of  an  Interim  Ontario  Drinking  Water  Objective  for 
Tritium  (MOEE  1993). 

A  total  of  84  written  responses  were  received  and  1 1  deputation  presentations  were 
made  dealing  with  various  aspects  of  the  rationale  for  setting  an  Interim  ODWO  of 
7,000  Bq/L  for  tritium.    A  list  of  respondents  is  attached  as  Appendix  2. 

In  reviewing  the  comments  submitted,  every  response  was  considered  carefully. 
Comments  ranged  from  short  letters  on  the  proposed  standard  through  to  detailed 
technical  submissions.    Comment  summaries  are  provided  in  Appendix  3.    All 
comments,  whether  oral  or  written,  received  equal  consideration.    Submissions 
received  after  March  10,  1994,  were  read  and  considered,  but  are  not  included  in  this 
report. 

When  analyzing  the  responses,  a  number  of  issues  were  identified.    Many  respondents 
addressed  more  than  one  issue. 

These  issues  were  categorized  as  follows: 
Overview  of  Public  Response 
Exposure 
Risk 

Feasibility 
Implementation 
Need  for  Additional  Studies 
Other  Comments  and  Recommendations 


14 


Overview  of 
Public  Response 

The  consultation  materials  distributed  posed  three  questions  and  encouraged  additional 
comments.   Responses  to  ACES' s  three  consultation  questions  were  divided  into  four 
categories  depending  on  how  the  question  regarding  the  acceptability  of  the  proposed 
standard  was  answered.    A  summary  is  presented  in  Table  1. 


Table  1.    Summary  of  Responses  Regarding  the  Proposed  Standard 


Comment 

Number 

% 

Yes,  the  proposed  standard  is  acceptable. 

17 

20 

No,  the  proposed  standard  is  not 
acceptable,  the  level  should  be  lower. 

43 

51 

No,  the  proposed  standard  is  not 
acceptable,  the  level  should  be  higher. 

4 

5 

Question  not  answered  directly. 

20 

24 

Total  comments  received 

84 

100 

The  proposed  standard  was  deemed  acceptable  by  17  people.   The  standard  was 
deemed  unacceptable  by  46  respondents,  4  recommending  that  the  level  be  higher  and 
42  recommending  that  the  level  be  lower.    The  question  was  not  answered  directly  by 
20  respondents. 

In  addition  to  responding  to  these  questions,  the  public  provided  ACES  with 
information  and  supporting  documentation  of  which  the  Committee  had  not  been 
previously  aware.    This  confirmed  to  ACES  the  value  of  the  public  consultation 
process. 


15 


Exposure 


Summary  of  Public  Comment 

In  response  to  ACES' s  question  on  the  appropriateness  of  the  proposed  standard,  two 
respondents  brought  to  ACES' s  attention  the  fact  that  the  basis  of  the  risk  assessment 
for  tritium  differed  fundamentally  from  that  for  all  non-radioactive  contaminants.    The 
entire  paradigm,  or  model,  on  which  risk  assessments  for  radionuclides  are  based 
makes  unique  assumptions  and  calculations.    The  public  comment  on  this  issue  pointed 
out  that  the  lifetime  risk  associated  with  environmental  radioactive  contaminants  is 
calculated  based  upon  consumption  of  drinking  water  containing  a  radioactive 
contaminant  every  day  for  only  one  year.    In  contrast,  the  lifetime  risk  associated  with 
environmental  chemical  contaminants  is  calculated  based  upon  consumption  of  drinking 
water  containing  a  chemical  contaminant  every  day  for  70  years  (the  average  life- 
span). 

Response  by  ACES 

The  final  draft  of  the  1993  revision  of  the  Ontario  Drinking  Water  Objectives 
document  states,  in  Section  1.2  Types  of  Objectives,  that  "Almost  all  objectives  are 
based  on  a  70  kg  person  consuming  1.5  litres1  of  water  per  day  for  70  years  (emphasis 
added)."    Setting  an  ODWO  on  a  lifetime  risk  estimate  based  on  only  one  year's 
exposure  to  a  contaminant  at  a  certain  level  represents  a  significant  departure  from  this 
stated  policy. 

The  proposed  tritium  level  of  7,000  Bq/L  represents  a  lifetime  risk  of  5  excess  cancers 
per  million  people  exposed  for  one  year.    The  MOEE,  in  proposing  7,000  Bq/L,  is 
consistent  with  the  international  radiation  protection  community's  risk  assessment 
practices.    Lifelong  (70  year)  exposure  to  7,000  Bq/L  would  result  in  approximately 
340  excess  fatal  cancers  per  million  people  exposed2.    ACES  considers  that  the 
ODWO  for  tritium  should  be  lower  than  the  proposed  level  because  the  international 
radiation  protection  community  based  the  lifetime  risk  level  on  only  one  year's 
exposure.    Extending  this  exposure  over  a  70  year  life-span  would  add  to  the  lifetime 
cancer  risk,  especially  if  exposure  occurred  in  one's  early  years  (See  further 
discussion  under  Risk). 


^e  MOEE' s  proposed  ODWO  for  tritium  assumes  a  2.0  litre  per  day  consumption  of 
drinking  water. 

2Please  refer  to  the  letter  in  Appendix  4  for  the  calculation  of  total  lifetime  risk  of  0.1 
mSv  received  annually  for  70  years.   This  calculation  was  provided  by  Dr.  P.J. 
Waight  of  the  Radiation  Protection  Bureau  of  Health  Canada. 


16 


Risk 


For  the  purposes  of  this  review,  ACES  accepts  the  international  radiation  protection 
community's  derivation  of  0.1  mSv  in  one  year  from  the  consumption  of  2.0  litres  of 
drinking  water  per  day  as  the  dose  which  will  result  in  5  fatal  cancers  per  million 
exposed  population.    If  this  dose  (i.e.,  0.1  mSv)  is  lifelong  (70  years),  U.S.  EPA 
estimates  that  between  300  -  1000  additional  fatal  cancers  per  million  exposed  would 
result.1     The  EPA  numbers  are  derived  from  the  BEIR  V  report  which  estimates  that 
520  additional  fatal  cancers  per  million  exposed  males  and  600  additional  fatal  cancers 
per  million  exposed  females  will  result  from  this  lifelong  dose  (BEER  V  1990). 

MOEE  proposes,  in  the  Rationale  Document,  that  an  acceptable  level  of  risk  for 
tritium  in  drinking  water  is  5  excess  cancers  per  million  people  exposed.    Based  on 
this  level  of  acceptable  risk  and  with  lifelong  exposure,  the  following  calculation  was 
performed: 

7,000  Bq/L  (proposed  level  for  one  year's  exposure)  /  70  years  (average  life-span)  = 

100  Bq/L. 

An  ODWO  of  100  Bq/L  represents  a  drinking  water  standard  with  an  acceptable  risk 
of  5  excess  cancers  per  million  people  following  lifelong  exposure. 


Summary  of  Public  Comment 

The  acceptable  risk  level  of  the  5  additional  cancers  per  one  million  people  exposed, 
as  proposed  in  the  MOEE' s  Rationale  Document,  was  challenged  by  three 
respondents.   In  general,  they  recommended  a  de  minimus  risk  of  1  excess  cancer  per 
one  million  people  exposed  as  a  conservative  public  health  approach. 

It  is  possible  that  many  of  the  respondents  were  not  aware  that  the  cancer  risk  referred 
to  in  the  Rationale  Document  was  the  risk  following  one  year's  exposure  and  not  a 
lifelong  exposure  (see  further  discussion  under  Exposure). 

Health  effects  other  than  fatal  cancer  were  cited  by  16  of  the  respondents  as  a 
rationale  for  the  lowering  of  the  proposed  standard.    The  public  expressed  particular 
concern  about  birth  defects,  non-fatal  cancers,  childhood  leukaemia,  effects  on 


'A  paper  from  the  U.S.  EPA' s  Science  Advisory  Board  entitled  Harmonizing  Chemical 
and  Radiation  Risk  Reduction  Strategies-A  Science  Advisory  Board  Commentary 
discusses  the  two  risk  paradigms  that  have  evolved  and  is  found  in  Appendix  5. 


17 


immunity,  and  Down's  Syndrome.    One  member  of  the  public  summed  up  their  view 
on  the  use  of  fatal  cancers  as  the  only  endpoint  of  concern  by  stating  that  "health  is 
more  than  the  absence  of  death".    Several  respondents  referred  to  the  AECB  studies 
which  reported  a  higher  incidence  of  childhood  leukaemia  and  Down's  Syndrome 
around  nuclear  generating  stations  (Clarke  and  McLaughlin  1989,  Clarke  and 
McLaughlin  1991,  Johnson  and  Rouleau  1991). 

The  public  cited  a  number  of  additional  factors  which  were  not  considered  in  the  risk 
estimates.    These  factors  included:  the  exposure  of  sensitive  populations  (12 
commenters),  (i.e.,  fetuses,  young  children,  women  of  childbearing  age,  etc.); 
synergistic  or  additive  effects  of  tritium  with  other  contaminants,  including 
radionuclides,  in  drinking  water  (11  commenters);  other  routes  or  sources  of  tritium 
exposure  (4  commenters);  organically  bound  tritium  (3  commenters);  the  potential  for 
tritium,  particularly  organically  bound  tritium,  to  bioaccumulate  (2  commenters);  the 
dose  conversion  factor  used  (2  commenters);  the  relative  biological  effectiveness 
(RBE)  of  tritium  (3  commenters);  the  validity  of  extrapolating  data  from  acute  high 
doses  to  chronic  low  doses  (1  commenter).    The  respondents  generally  supported  a 
much  lower  standard  for  tritium  in  drinking  water  as  a  result  of  these  factors. 

Two  commenters  raised  the  issue  of  the  potential  effects  on  fetuses  in  utero  of  periodic 
"pulses"  of  tritium  in  drinking  water.    These  pulses  result  from  intermittent  higher 
level  tritium  emissions.   Their  concerns  centred  on  the  exposure  of  pregnant  women 
due  to  the  susceptibility  of  rapidly  dividing  embryonic  cells  to  radiation. 

The  "Petkau  effect"  was  referred  to  by  several  respondents  and  one  expressed  concern 
over  its  implications  for  a  greater  risk  of  health  problems  following  continuous  low 
level  radiation  exposure. 

Six  respondents  raised  the  issue  of  the  historical  risk  assessment  by  international 
agencies  such  as  the  International  Commission  on  Radiological  Protection  (ICRP),  the 
World  Health  Organization  (WHO)  and  the  National  Council  on  Radiation  Protection 
and  Measurements  (NCRP).    These  agencies  have  reduced  the  acceptable  risk  by  a 
factor  of  five  in  their  most  recent  recommendations1.    Respondents  raised  concerns 
regarding  these  agencies  past  underestimation  of  the  risks  associated  with  radionuclides 
and  expressed  a  lack  of  confidence  that  these  new  risk  estimates  are  "correct". 


'A  revised  estimate  of  the  risk  of  a  lifetime  fatal  cancer  for  the  general  population  has 
been  estimated  by  the  International  Commission  on  Radiological  Protection  (ICRP)  to 
be  5  x  10"2  per  sievert  (ICRP  1990).   In  light  of  this  change,  the  World  Health 
Organization  revised  its  reference  level  of  committed  effective  dose  to  0. 1  mSv  from  1 
year's  consumption  of  drinking  water  (WHO  1993).   This  is  a  five  fold  reduction  from 
the  WHO'S  previous  reference  level  of  0.5  mSv. 


18 


Of  the  respondents  who  recommended  a  lower  level  (see  Overview  of  Public 
Responses),  16%  supported  setting  the  standard  at  background  levels  and  51% 
supported  zero  discharge.    (Many  members  of  the  public  recommended  zero  as  the 
acceptable  level  in  drinking  water.    ACES  recognizes  that  the  ambient  concentration 
will  never  be  zero  due  to  the  existence  of  natural  sources  of  tritium  contamination  and 
took  the  public's  support  of  a  drinking  water  standard  of  zero  to  indicate  support  of 
zero  discharge).    Numerous  commenters  cited  the  International  Joint  Commission's 
(JJC)  position  of  virtual  elimination  of  persistent  toxins  as  their  rationale.    They  stated 
that  the  JJC  considers  radionuclides  with  half-lives  greater  than  six  months  as 
persistent  toxic  substances.    In  its  Seventh  Biennial  Report  on  Great  Lakes  Water 
Quality  (JJC  1994)  the  JJC  suggests,  in  its  Recommendations  to  Federal  and 
State/Provincial  Governments,  that  "Governments  incorporate  those  radionuclides 
which  meet  the  definition  of  persistent  toxic  substances  in  their  strategy  for  virtual 
elimination.  " 

Six  percent  of  respondents  went  on  to  recommend  staged  reduction  levels  with  precise 
time  lines  to  reflect  the  decrease  in  background  tritium  levels  as  a  result  of  the  decay 
of  tritium  from  weapons  testing  over  time. 

One  respondent  recommended  that  radioisotopes  be  included  in  the  MOEE's  Priority 
Pollutants  List. 


Response  by  ACES 

1)   Acceptable  Risk  Level: 

The  determination  of  an  acceptable  level  of  risk  depends  on  a  number  of  factors. 
When  setting  environmental  standards,  regulatory  agencies  will  often  accept  a  risk  of  1 
excess  cancer  per  million  people  exposed  if  the  following  circumstances  are  met: 

-multiple  media  through  which  exposure  can  occur; 

-a  large  affected  population. 

A  risk  of  one  excess  cancer  per  one  hundred  thousand  people  exposed  (i.e.,  10  per 
million)  is  often  deemed  acceptable  if  there  is: 

-a  single  medium  of  exposure; 

-a  limited  affected  population. 

In  the  case  of  tritium,  nuclear  generating  stations  represent  a  point  source  for  tritium 
in  drinking  water.   However,  there  is  more  than  one  medium  of  exposure  (e.g.,  air, 
food,  etc.),  and  there  is  the  potential  for  a  large  population  to  be  impacted. 
Therefore,  an  intermediate  risk  level  of  5  excess  cancers  per  miflion  people  exposed  is 
reasonable.   MOEE  currently  has  no  formal  policy  on  risk  assessment  which  codifies 
the  standard  setting  process. 


19 


2)   Health  Effects  Other  Than  Fatal  Cancers: 

The  risk  estimates  carried  out  by  the  international  radiological  community  identify 
fatal  cancers  as  the  critical  endpoint  when  setting  an  allowable  dose.    The  WHO 
expressly  excludes  health  risks  from  non-fatal  cancers  and  hereditary  effects.    ACES 
considers  that  chronic  environmental  exposure  to  ionizing  radiation  presents  health 
risks  over  and  above  fatal  cancers,  including  non-fatal  cancers  and  multigenerational 
effects. 

The  risk  estimates  for  radionuclides  served  originally  as  a  framework  for  occupational 
standards  for  radiation  protection  for  atomic  workers.    There  are  substantial 
differences  between  occupational  and  environmental  exposure  to  contaminants. 
Occupational  standards  are  generally  established  based,  in  part,  on  the  following 
assumptions: 

-a  healthy  adult  population; 

-assuming  a  voluntary  risk; 

-individuals  are  exposed  over  a  limited  number  of  hours  per  day  and  a  limited 

number  of  years,  not  over  their  lifetime. 

Factors  such  as  exposure  of  sensitive  populations,  additive  effects,  other  routes  of 
exposure,  etc.,  are  not  taken  into  account  in  the  risk  estimates  for  radionuclides. 
These  factors  raise  issues  of  uncertainty  in  the  risk  calculations.    ACES  agrees  that 
these  additional  sources  of  uncertainty  are  areas  of  concern. 


3)   Uncertainty  Factors: 

The  dose  conversion  factor  used  for  tritium,  its  relative  biological  effectiveness  and 
the  contribution  to  risk  of  organically  bound  tritium  are  all  subjects  of  controversy 
within  the  radiological  community.    For  example,  the  RBE  for  tritium  in  the  Rationale 
Document  is  assumed  to  be  one.    A  recent  article  in  the  radiation  protection  literature 
concludes  that  the  RBE  is  higher  than  one  (Straume  and  Carsten  1993).    Changes  in 
any  of  the  above  cited  issues  would  likely  result  in  a  reduction  of  the  allowable  dose. 

The  "Petkau  effect"  refers  to  cell  membrane  damage  caused  by  continuous,  low  level 
exposure  to  beta  emitters  (Graeub  1992).   This  "effect"  is  based  on  the  research 
carried  out  by  Dr.  Abram  Petkau  on  non-living  membranes.   His  studies  showed  that 
chronic  exposure  to  low  levels  of  tritium  lowered  the  dose  required  to  break  the 
membrane.    The  Committee  considered  that,  although  interesting,  the  Petkau  effect 
may  not  be  relevant  for  human  risk  assessment  because  the  studies  were  performed  on 
artificial  phospholipid  membranes,  in  vitro,  which  lack  the  repair  mechanisms  present 
in  living  systems. 

The  combination  of  an  intermediate  acceptable  risk  level,  uncertainties  about  other 
potential  health  risks  from  chronic  environmental  exposures  to  radiation  and  additional 

20 


uncertainties  in  the  parameters  used  in  determining  the  risk  estimate  for  tritium 
provide  impetus  to  lower  the  acceptable  risk  level  from  5  excess  cancers  in  one 
million  people  exposed  to  one  in  one  million.    This  risk  level  would  result  in  an 
ODWO  of: 

100  Bq/L   (level  reflecting  lifelong  exposure)  -s-  5    =20  Bq/L 


4)   Historical  Risk  Assessment: 

ACES  agrees  that  the  agencies  responsible  for  risk  assessment  of  radionuclides  have 
indicated  that,  in  the  past,  they  underestimated  the  risk  these  contaminants  pose. 
Consequently,  the  latest  recommendations  of  the  ICRP  and  the  WHO  have  been 
reduced  by  a  factor  of  five  to  reflect  the  revised  risk  estimates. 


5)    Virtual  Elimination: 

ACES  endorses  the  public's  support  of  the  principle  of  virtually  eliminating  persistent 
toxic  substances  from  the  environment  and  of  establishing  a  schedule  for  this  reduction 
over  time.    Tritium  is  persistent,  with  a  half-life  of  12.3  years,  and  is  a  human 
carcinogen.    ACES  agrees  with  the  DC  position  on  the  identification  of  radionuclides 
with  a  half- life  greater  than  six  months  as  persistent  toxic  substances. 


Recommendations 

ACES  recommends  that  a  multimedia  approach  be  used  in  establishing  tritium 
standards.    Recognizing  the  existence  of  other  potential  pathways  of  exposure  to 
tritium  in  addition  to  drinking  water,  ACES  further  recommends  that  the  Minister  of 
the  Environment  and  Energy  should  undertake  discussions  with  other  jurisdictions  to 
implement  this  recommendation. 

ACES  further  recommends  that  the  MOEE  establish  a  policy  on  risk  estimation  with 
standard  methodologies  to  evaluate  risk  and  clear  criteria  for  when  deviations  from 
that  methodology  are  required. 

ACES  recommends  that  radioisotopes  that  are  toxic,  persistent,  and  that  have  the 
potential  to  bioaccumulate  should  be  included  in  the  Priority  Pollutant  List  developed 
by  the  MOEE. 


Feasibility 


Summary  of  Public  Comment 

The  issue  of  cost  analysis  in  applying  the  ODWO  was  raised  by  6  respondents. 
Comments  centred  on  the  need  for  demonstrated  benefits  in  terms  of  pollution 
reduction  given  the  potential  economic  costs  of  a  stringent  tritium  drinking  water 

21 


objective.    Respondents  felt  that  this  was  not  "beyond  the  scope"  of  the  report,  as 
stated  in  the  Rationale  Document.    The  four  respondents  that  supported  an  ODWO  of 
40,000  Bq/L  all  commented  that  the  cost  associated  with  a  reduction  of  the  standard 
was  a  factor  in  their  recommendations. 

Five  commenters  addressed  the  lack  of  treatment  technologies  to  remove  tritium  from 
drinking  water.    They  expressed  concerns  that  due  to  the  absence  of  treatment 
technologies,  the  tritium  level  the  consumer  receives  is  the  same  level  as  in  the  raw 
water.    The  respondents  used  this  rationale  to  support  a  reduction  in  tritium  emission 
levels.    Concerns  about  the  lack  of  treatment  technologies  for  tritium  in  drinking  water 
resulted  in  an  additional  5  respondents  discussing  the  location  of  water  treatment 
plants,  with  recommendations  that  they  be  situated  in  areas  that  can  meet  whatever 
drinking  water  target  level  is  set.    One  commenter  recommended  that  Ontario  adopt 
the  United  States  ban  on  building  water  supply  plants  within  a  five  mile  radius  of 
nuclear  generating  stations. 

Response  by  ACES 

ACES' s  consultation  was  based  on  the  MOEE's  proposed  ODWO  of  7,000  Bq/L  and 
the  feasibility  thereof.    The  Rationale  Document  did  not  consider  the  feasibility  of 
lower  levels.    ACES  has  no  comprehensive  information  on  the  feasibility  of  an 
ODWO  of  less  than  or  equal  to  100  Bq/L.    The  information  supplied  by  the  MOEE's 
Drinking  Water  Surveillance  Program  (DWSP)  suggests  that  100  Bq/L  is  rarely 
exceeded  and  that  20  Bq/L  is  exceeded  periodically  near  nuclear  facilities1. 

Background  levels  of  tritium  in  the  environment  are  declining  due  to  the  decay  of 
fallout  over  time.    Currently,  the  most  significant  source  of  tritium  in  drinking  water 
that  would  result  in  a  drinking  water  level  in  excess  of  20  Bq/L  is  emissions  from 
nuclear  facilities.   No  effective  treatment  technologies  for  the  removal  of  tritium  from 
drinking  water  supplies  exist.   ACES  agrees  that  the  lack  of  an  effective  treatment 
technology  for  tritium  in  drinking  water  is  of  concern  and  considers  that  this  provides 
additional  support  for  reducing  tritium  emissions. 

ACES  believes  that  there  is  a  need  to  investigate  an  ODWO  of  20  Bq/L  and  below  in 
terms  of  technical  feasibility  and  financial  feasibility.    Several  years  may  be  needed 
for  these  feasibility  studies,  therefore  ACES  proposes  a  five  year  target  for  the 
ODWO  of  20  Bq/L  and  the  policy  options  implied. 


'Page  19  of  the  Rationale  Document  for  the  Development  of  an  Interim  Ontario 
Drinking  Water  Objective  for  Tritium  (MOEE  1993)  states  that  "...the  levels  of  tritium 
in  drinking  water  supplies  in  Ontario  rarely  exceed  100  Bq/L."   Appendix  E.l  (page 
25)  of  the  same  document  lists  the  tritium  results  of  the  1991  Drinking  Water 
Surveillance  Program  (DWSP).    Of  the  109  water  supply  plants  surveyed,  only  the 
Ajax  Water  Treatment  Plant  reported  a  tritium  level  over  100  Bq/L. 
Appendix  7  lists  the  1991  tritium  data  from  the  Nuclear  Surveillance  Program  as 
reported  in  Appendix  E.2  of  the  MOEE  Rationale  Document. 


22 


Due  to  the  lack  of  an  effective  means  of  removing  tritium  from  drinking  water,  the 
proximity  of  nuclear  facilities  should  be  borne  in  mind  when  approvals  are  sought  for 
the  construction  or  expansion  of  water  supply  plants. 

By  summing  the  effects  of  all  radionuclides  and  applying  a  committed  effective  dose  to 
the  total,  the  radiation  risk  assessment  paradigm  implicitly  weighs  the  benefits  of  the 
nuclear  industry  at  a  much  greater  level  than  those  of  other  industries  (e.g.,  the 
agrochemical  industry  for  which  each  additional  pesticide  or  herbicide  is  evaluated  and 
regulated  independently).    ACES  challenges  this  weighting  and  questions  the  rationale 
for  attributing  these  extraordinary  benefits  to  the  nuclear  industry  while  other 
industrial  sectors  are  treated  less  generously. 

Recommendations 

ACES  recommends  that  the  Ontario  Drinking  Water  Objective  for  Tritium  be  set 
immediately  at  100  Bq/L.  ACES  further  recommends  that,  due  to  the  fact  that 
tritium  is  a  human  carcinogen  and  because  of  the  many  uncertainties  in  the  risk 
assessment,  the  tolerable  level  of  tritium  in  drinking  water  be  reduced  to  20  Bq/L 
in  5  years  with  the  goal  of  further  reduction  as  human  contributions  to  tritium 
background  levels  decline.  The  five  year  schedule  for  the  reduction  acknowledges 
the  need  for  technical  and  financial  feasibility  studies  on  the  ODWO  of  20  Bq/L. 
In  addition,  ACES  recommends  that  this  standard  be  applied  as  a  health-based 
Maximum  Acceptable  Concentration,  so  that  when  this  drinking  water  standard 
is  exceeded,  an  alternative  water  supply  should  be  made  available. 

ACES  recommends  that  the  MOEE  undertake  a  comparative  cost  analysis  of  different 
methods  to  achieve  the  recommended  ODWO  of  100  Bq/L  and  the  five  year  target  of 
20  Bq/L. 

ACES  further  recommends  that  the  MOEE  ensure  that  the  feasibility  of  additional 
tritium  emission  control  strategies  be  assessed. 


Implementation 


Summary  of  Public  Comment 

A  number  of  respondents  (12)  raised  the  question  of  jurisdictional  authority  over 
radionuclides.   Many  of  those  expressed  confusion  over  the  multiplicity  and  range  of 
water-borne  tritium  standards,  and  were  unsure  about  which  ones  are  "safe".   This 
range  includes  the  current  Atomic  Energy  Control  Board's  (AECB)  derived  emission 
limit  for  the  Pickering  Nuclear  Generating  Station  of  210,000  Bq/L1,  the  current 
Canadian  Drinking  Water  Guideline  of  40,000  Bq/L,  the  proposed  ODWO  of  7,000 
Bq/L  and  the  U.S.  Environmental  Protection  Agency  (U.S.  EPA)  drinking  water 
standard  of  740  Bq/L. 


23 


The  inclusion  of  radionuclides  as  persistent  toxins  in  the  International  Joint 
Commission's  most  recent  biennial  report  was  mentioned  by  50%  of  those  who 
commented  on  jurisdictional  issues. 

Four  comments  from  respondents  dealt  with  the  monitoring  of  tritium  and  three 
comments  addressed  the  impact  of  transboundary  sources  of  tritium  in  drinking  water, 
especially  the  Fermi  II  radioactive  waste  water  releases  by  Detroit  Edison  to  Lake  Erie 
in  February  and  March,  1994.    The  comments  expressed  concern  that  there  is  no 
reliable  on  line  monitor  for  sampling  and  tracking  tritium  discharges  into  water. 

Two  respondents  raised  the  issue  of  enforcement  of  the  drinking  water  objectives. 
These  comments  expressed  frustration  with  ineffective  'guidelines'  and  recommended 
that  enforcement  become  "credible  and  rational". 

An  advisory  level  in  addition  to  the  standard  was  discussed  by  seven  respondents,  five 
of  which  supported  this  concept.    The  advisory  was  suggested  to  provide  an  alert  to 
communities  when  tritium  contamination  exceeds  background  levels,  so  that  people 
can  choose  not  to  drink  the  tap  water. 

Response  by  ACES 

The  regulation  of  radionuclides  is,  indeed,  complex.    Various  jurisdictions  have 
different  responsibilities.    The  regulation  of  all  "nuclear  facilities"  and  their  discharges 
is  the  mandate  of  the  federal  government  under  the  Atomic  Energy  Control  Act. 

Because  nuclear  facilities  represent  a  point  source  for  tritium  in  drinking  water  and 
because  there  is  no  water  treatment  technique  to  remove  tritium,  the  standard  for 
tritium  in  Ontario  drinking  water  may  have  an  impact  on  the  emissions,  and  therefore 
possibly  the  operations,  of  Ontario  Hydro  and  AECL  nuclear  plants.    ACES  was 
unable  to  establish  whether  or  not  additional  controls  on  tritium  releases  from  these 
plants  are  possible,  and  based  its  recommendation  primarily  on  the  health 
considerations  of  tritium  exposure  from  drinking  water. 


1  The  AECB  derived  emission  limit  is  an  allowable  release  standard  to  water  from 
nuclear  facilities.    Although  these  emissions  will  affect  tritium  levels  in  drinking 
water,  this  is  not  a  drinking  water  standard. 


24 


More  than  90%  of  Canada's  nuclear  generating  capacity  resides  in  Ontario,  under  the 
auspices  of  Ontario  Hydro.    Ontario  Hydro  is  a  Provincial  Crown  corporation 
responsible  for  the  production  and  delivery  of  electrical  power.    Ontario  Hydro  reports 
to  the  Minister  of  the  Environment  and  Energy. 

Each  province  has  jurisdiction  over  its  own  water  supplies.    Section  29.(1)  of  the 
Ontario  Water  Resources  Act  states  that  "For  the  purposes  of  this  Act,  the  Minister 
has  the  supervision  of  all  surface  waters  and  ground  waters  in  Ontario."  (OWRA 
1994)   Section  75.-(l)(i)  of  this  same  Act  states  that  "[The  Lieutenant  Governor  in 
Council  may  make  regulations,]  prescribing  standards  of  quality  for  potable  and  other 
water  supplies,  sewage  and  industrial  waste  supplies,  sewage  and  industrial  waste 
effluents,  receiving  streams  and  water  courses;".   It  is  on  these  bases  that  the  Province 
has  jurisdiction  over  the  quality  of  drinking  water  supplies. 

In  a  section  of  their  submission  entitled  "Different  Limits  for  Tritium  in  Drinking 
Water"  Ontario  Hydro  stated  that  "It  should  be  noted  that  the  AECB  operating  licenses 
specify  that  the  nuclear  station  must  also  comply  with  all  applicable  provincial  and 
local  regulations.    This  implies  that  we  must  comply  with  the  most  restrictive 
regulations  in  cases  where  there  is  overlap  of  jurisdiction.  " 

The  most  recent  draft  of  the  Ontario  Drinking  Water  Objectives  (MOEE,  1993)  states 
that  "The  objectives  outlined  in  this  document  prescribe  standards  of  quality  for 
drinking  water  supplies.    In  carrying  out  its  responsibilities  under  section  53  OWRA 
[Ontario  Water  Resources  Act],  the  MOEE  applies  the  ODWO's  in  approving  the 
establishment  of  any  water  works  or  the  extension  of  or  change  in  any  existing  water 
works...".    The  Approvals  Branch  of  the  MOEE,  through  the  granting  of  Certificates 
of  Approval,  specifies  monitoring  requirements.    Regional  staff  of  the  MOEE  are 
responsible  for  enforcing  these  monitoring  requirements  at  all  water  supply  systems. 
The  Medical  Officer  of  Health,  through  the  Health  Protection  and  Promotion  Act  has 
the  authority  to  judge  whether  water  is  safe  for  human  consumption.   ODWOs  may  be 
used  for  this  purpose. 

ACES  supports  the  concept  of  easier  public  access  to  drinking  water  survey 
information.    In  their  submission,  Atomic  Energy  of  Canada  Limited  Research 
(AECL)  suggested  that  drinking  water  survey  information  be  provided  on  a  regular 
basis  to  the  public  in  communities  which  express  significant  concern  about  their  water 
quality.    One  means  they  suggested  for  providing  this  information  was  through  the 
regular  publication  in  newspapers  of  the  concentrations  in  drinking  water  of  all  health 
related  parameters  in  comparison  to  their  respective  limits. 

Recommendations 

ACES  recommends  that  frequent  monitoring  and  timely,  regular  and  public  reporting 
of  tritium  levels  in  nuclear  facilities'  emissions  and  water  treatment  plant  intakes  in  the 
vicinity  of  nuclear  facilities  should  be  ensured  by  the  MOEE. 

25 


ACES  is  unaware  of  any  monitoring  program  currently  in  place  that  would  detect 
tritium  pulses.   Due  to  the  concerns  raised  regarding  potential  risks  to  the  fetus  in 
utero,  ACES  recommends  that  the  MOEE  ensure  that  the  timely  reporting  of  periodic 
tritium  pulses  is  pursued. 

ACES  strongly  supports  the  principles  of  pollution  prevention  and  the  phase  out  of 
persistent,  toxic  contaminants,  like  tritium.    In  keeping  with  these  goals,  ACES 
recommends  that  discussions  should  be  initiated  with  Ontario  Hydro  and  AECL 
regarding  the  feasibility  of  reducing  tritium  emission  levels  from  nuclear  facilities  in 
Ontario. 

ACES  recommends  that  the  Ministry  of  Labour  Radiological  Drinking  Water 
Monitoring  data  should  be  made  available  to  the  public  in  an  accessible  and  timely 
manner  and  published  along  with  the  Drinking  Water  Surveillance  Program  data. 


Need  for 

Additional 

Studies 


Summary  of  Public  Comment 

Five  submissions  dealt  with  the  issue  of  the  need  for  additional  health  studies.  Four 
commenters  expressed  concerns  over  the  lack  of  information  on  long  term,  low  level 
radiation  ingestion  exposure  effects. 

Response  by  ACES 

ACES  agreed  that  there  is  a  lack  of  information  on  the  long  term,  low  level  ingestion 
exposure  effects  of  radiation  and  has  concerns  over  the  promised  follow  up  health 
studies  by  the  AECB  that  have  yet  to  be  conducted.   ACES  considers  such  studies  to 
be  required,  but  believes  that  the  adverse  health  effects  of  ionizing  radiation  are 
sufficiently  well  established  that  public  monies  would  be  more  effectively  spent  in 
controlling  tritium  releases  to  the  environment  rather  than  on  further  study  of  its  health 
effects. 

Recommendations 

ACES  recommends  that  follow  up  studies  on  long  term,  low  level  exposures  to 
radiation  be  completed  as  recommended  by  previous  AECB  reports,  but  that  these 
studies  not  proceed  immediately  if  the  cost  associated  with  them  would  delay  the 
implementation  of  the  recommended  standard. 

ACES  further  recommends  that  representatives  selected  by  the  community  be  included 
in  the  planning  committee  for  future  health  studies  to  increase  public  confidence  in  the 
study. 


26 


Other  Comments 

and 

Recommendations 

Summary  of  Public  Comment 

A  number  of  other  comments  and  recommendations  were  received  during  the 
consultation.    These  included  suggestions  regarding  the  process  (3  comments),  i.e., 
requests  for  a  "full"  tritium  review,  criticisms  and  suggestions  for  improvement  of  the 
structure  and  content  of  the  Rationale  Document  (4  comments),  and  concerns 
regarding  the  ecosystem  effects  of  tritium  contamination  (2  comments). 

Response  by  ACES 

In  general,  ACES  was  pleased  with  the  process  and  with  the  extent  and  quality  of  the 
responses  received  to  the  request  for  comment.    About  37%  of  those  who  requested 
additional  information  actually  commented.    ACES  felt  this  degree  of  response  was 
excellent  given  the  scientific  nature  and  complexity  of  the  issues. 


27 


Summary  of 
Recommendations 

ACES  recommends  that  the  Ontario  Drinking  Water  Objective  for  Tritium  be  set 
immediately  at  100  Bq/L.  ACES  further  recommends  that,  due  to  the  fact  that 
tritium  is  a  human  carcinogen  and  because  of  the  many  uncertainties  in  the  risk 
assessment,  the  tolerable  level  of  tritium  in  drinking  water  be  reduced  to  20  Bq/L 
in  5  years  with  the  goal  of  further  reduction  as  human  contributions  to  tritium 
background  levels  decline.  The  five  year  schedule  for  the  reduction  acknowledges 
the  need  for  technical  and  financial  feasibility  studies  on  the  ODWO  of  20  Bq/L. 
In  addition,  ACES  recommends  that  this  standard  be  applied  as  a  health-based 
Maximum  Acceptable  Concentration,  so  that  when  this  drinking  water  standard 
is  exceeded  an  alternative  water  supply  should  be  made  available. 

ACES  recommends  that  a  multimedia  approach  be  used  in  establishing  tritium 
standards.    Recognizing  the  existence  of  other  potential  pathways  of  exposure  to 
tritium  in  addition  to  drinking  water,    ACES  further  recommends  that  the  Minister  of 
the  Environment  and  Energy  should  undertake  discussions  with  other  jurisdictions  to 
implement  this  recommendation. 

ACES  further  recommends  that  the  MOEE  establish  a  policy  on  risk  estimation  with 
standard  methodologies  to  evaluate  risk  and  clear  criteria  for  when  deviations  from 
that  methodology  are  required. 

ACES  recommends  that  radioisotopes  that  are  toxic,  persistent,  and  that  have  the 
potential  to  bioaccumulate  should  be  included  in  the  Priority  Pollutant  List  developed 
by  the  MOEE. 

ACES  recommends  that  the  MOEE  undertake  a  comparative  cost  analysis  of  different 
methods  to  achieve  the  recommended  ODWO  of  100  Bq/L  and  the  five  year  target  of 
20  Bq/L. 

ACES  further  recommends  that  the  MOEE  ensure  that  the  feasibility  of  additional 
tritium  emission  control  strategies  be  assessed. 

ACES  recommends  that  frequent  monitoring  and  timely,  regular  and  public  reporting 
of  tritium  levels  in  nuclear  facilities'  emissions  and  water  treatment  plant  intakes  in  the 
vicinity  of  nuclear  facilities  should  be  ensured  by  the  MOEE. 

ACES  is  unaware  of  any  monitoring  program  currently  in  place  that  would  detect 
tritium  pulses.    Due  to  the  concerns  raised  regarding  potential  risks  to  the  fetus  in 
utero,  ACES  recommends  that  the  MOEE  ensure  that  the  timely  reporting  of  periodic 
tritium  pulses  is  pursued. 


28 


ACES  strongly  supports  the  principles  of  pollution  prevention  and  the  phase  out  of 
persistent,  toxic  contaminants,  like  tritium.    In  keeping  with  these  goals,  ACES 
recommends  that  discussions  should  be  initiated  with  Ontario  Hydro  and  AECL 
regarding  the  feasibility  of  reducing  tritium  emission  levels  from  nuclear  facilities  in 
Ontario. 

ACES  recommends  that  the  Ministry  of  Labour  Radiological  Drinking  Water 
Monitoring  data  should  be  made  available  to  the  public  in  an  accessible  and  timely 
manner  and  published  along  with  the  Drinking  Water  Surveillance  Program  data. 

ACES  recommends  that  follow  up  studies  on  long  term,  low  level  exposures  to 
radiation  be  completed  as  recommended  by  previous  AECB  reports,  but  that  these 
studies  not  proceed  immediately  if  the  cost  associated  with  them  would  delay  the 
implementation  of  the  recommended  standard. 

ACES  further  recommends  that  representatives  selected  by  the  community  be  included 
in  the  planning  committee  for  future  health  studies  to  increase  public  confidence  in  the 
study. 


29 


References 


Advisory  Committee  on  Environmental  Standards  (ACES).    1992.    A  Standard  for  N- 
Nitrosodimethylamine  (NDMA)  A  recommendation  to  the  Minister  of  the 
Environment.    ACES  Report  92-01. 

Clarke,  E.A.,  McLaughlin,  J.,  and  Anderson,  T.W.    1989.    Childhood  leukaemia 
around  Canadian  nuclear  facilities  -  Phase  I.    AECB. 

Clarke,  E.A.,  McLaughlin,  J.,  and  Anderson,  T.W.    1991.    Childhood  leukaemia 
around  Canadian  nuclear  facilities  -  Phase  II .    AECB. 

Committee  on  the  Biological  Effects  of  Ionizing  Radiation  (BETR).    1990.    Health 
Effects  of  Exposure  to  Low  Levels  of  Ionizing  Radiation.    BEIR  V.    National 
Academy  Press.    Washington,  D.C. 

Graeub,  R.    1992.   The  Petkau  Effect:  Nuclear  Radiation,  People  and  Trees.    Four 
Walls  Eight  Windows  Press.    New  York,  N.Y. 

International  Commission  on  Radiological  Protection  (ICRP).    1991.    1990 
Recommendations  of  the  International  Commission  on  Radiological  Protection.    ICRP 
Publication  No.  60.  Pergamon  Press.    Elmsford,  N.Y. 

International  Joint  Commission  (IJC).    1994.    Seventh  Biennial  Report  on  Great  Lakes 
Water  Quality.    International  Joint  Commission,  Washington  D.C.  and  Ottawa, 
Ontario. 

Johnson,  K.C.,  and  Rouleau,  J.    1991.    Tritium  releases  from  the  Pickering  Nuclear 
Generating  Station  and  birth  defects  and  infant  mortality  in  nearby  communities  1971- 
1988.    AECB  Project  No.  7.156.1 

Ministry  of  the  Environment  and  Energy  (MOEE).    1993.    Ontario  Drinking  Water 
Objectives  (Final  Draft- 1993).   Water  Resources  Branch. 

Ministry  of  the  Environment  and  Energy  (MOEE).    1993.   Rationale  Document  for 
the  Development  of  an  Interim  Ontario  Drinking  Water  Objective  for  Tritium. 
Standards  Development  Branch. 

Ontario  Hydro,  Health  and  Safety  Division.    1992.    Annual  Summary  and  Assessment 
of  Environmental  Radiological  Data  for  1991.  Ontario  Report  HSD-HP-92-9. 


30 


Ontario  Water  Resources  Act.    1994.    Queen's  Printer  for  Ontario. 

Straume,  T.,  and  Carsten,  A.L.    1993.    Tritium  radiobiology  and  relative  biological 
effectiveness.   Health  Physics  65(6):  657-672. 

World  Heath  Organization  (WHO).    1993.    Guidelines  for  Drinking  Water  Quality. 
Second  Edition.    World  Health  Organization,  Geneva. 


31 


Appendix  1:    Background  Material  on  Tritium 

Ontario 

Advisory  Comité  40  St  Clair  Avenue  West  40.  avenuo  St  Clair  ou«3t 

Committee  OP  Consultatif  Suite  401  Bureau  401 

Environmental  des  normes  Tof°"to  ON  M4V1M2  ibromoON  M4V1M2 

Standards  environnementales 


TRITIUM 


January,  1994 


The  Honourable  Bud  Wildman,  Minister  of  the  Environment  and  Energy,  has  asked  ACES  to 
conduct  a  public  consultation  and  make  recommendations  on  his  Ministry's  proposed  Interim 
Ontario  Drinking  Water  Objective  for  Tritium  of  7,000  Becquerels  per  litre  (Bq/L). 
The  current  Ontario  Drinking  Water  Objective  for  radionuclides,  including  tritium,  is  40,000 
Bq/L. 

ACES  is  an  independent  advisory  body  responsible  for  recommending  to  the  Minister  sound, 
practical  standards  for  environmental  contaminants,  as  well  as  policies,  principles  and 
procedures  for  setting  environmental  standards. 

We  are  writing  to  ask  for  your  comments  on  this  proposed  standard.  If  you  are  concerned 
about  the  environment  and  would  like  to  make  a  difference,  we  urge  you  to  get  involved  in 
this  review. 

ACES  will  be  holding  an  information  session  in  Ajax  on  January  27,  1994,  at  the  Ajax 
Recreation  Centre,  75  Centennial  Road,  Ajax,  at  which  we  will  explain  our  public 
consultation  process.   We  have  invited  Ministry  of  the  Environment  and  Energy  (MOEE) 
staff  to  answer  your  questions  about  the  development  of  the  standard.   If  you  cannot  attend 
this  meeting  and  wish  more  information,  a  record  of  the  session  can  be  ordered.    The 
advertisement  on  the  reverse  provides  important  information  regarding  the  consultation 
program. 

We  would  appreciate  it  if  you  would  advise  others  who  might  have  an  interest  in  this  issue  of 
this  consultation. 

The  deadline  for  written  comments  is  March  10,  1994. 

Disponible  en  français  sur  demandé.  (Please  see  over) 

Important  information  enclosed  regarding: 

1)  Consultation  on  the  Proposed  Soil,  Drinking  Water  and  Air  Standards  for  Lead; 

2)  ACES's  mailing  list. 


32 


Setting  a  standard 
for  environmental 
protection 

WE  WANT  TO 
HEAR  FROM  YOU 
ABOUT  TRITIUM 


The  Minister  of  the  Environment  &  Energy  has  requested 
that  the  Advisory  Committee  on  Environmental  Standards 
(ACES)  conduct  a  public  consultation  on  the  proposed  new 
Interim  Ontario  Drinking  Water  Objective  of  7,000 
Becquerels/Litre  (Bq/L)  for  Tritium.  The  current  Ontario 
Drinking  Water  Objective  is  40,000  Bq/L. 

ACES  was  established  to  contribute  to  environmental 
improvement  by  advising  the  Minister  on  standards  for 
environmental  contaminants.  We  are  seeking  public  input 
before  reporting  to  the  Minister  and  would  like  to  invite 
you  to  take  part  in  this  public  consultation. 

ACES  is  particularly  interested  in  your  answers  to  the  fol- 
lowing questions,  although  we  welcome  any  other  com- 
ments you  may  have: 

1 .  Is  the  proposed  standard  acceptable? 

2.  If  noti  what  is  the  basis  for  finding  the 
proposed  level  unacceptable? 

3.  Do  you  have  an  alternative  level  to  propose 
and  what  is  your  rationale  for  suggesting 
this  level? 

The  deadline  for  written  comments  is  March  10,  1994.  If 
you  are  concerned  about  the  environment  and  would  like 
to  make  a  difference  then  we  urge  you  to  get  involved! 

For  further  information,  and  copies  of  the  documentation, 
please  contact: 

Advisory  Committee  on  Environmental  Standards 
40  St.  Clair  Ave.  West,  Suite  401 
Toronto,  Ontario  M4V  1M2 

Telephone:  (416)  314-9265 
Fax:  (416)  314-9270 


Ontario 


33 


Background  Documents  for  Tritium 

The  following  documents  were  used  in  the  development  of  the  proposed  tritium 
standard: 

1.  Health  and  Welfare  Canada.    1993.    Guidelines  for  Canadian  Drinking  Water 
Quality-Fifth  Edition.   Canada  Communications  Group  -  Publishing.    Ottawa, 
Canada. 

2.  National  Council  on  Radiation  Protection  and  Measurements  (NCRP).    1987. 
Ionizing  Radiation  Exposure  of  the  Population  of  the  United  States.   NCRP  Report 
No.  93.   National  Council  on  Radiation  Protection  and  Measurements.   Bethesda, 
Maryland. 

3.  Committee  on  the  Biological  Effects  of  Ionizing  Radiation  (BEIR).    1990.   Health 
Effects  of  Exposure  to  Low  Levels  of  Ionizing  Radiation.   BEIR  V.   National 
Academy  Press.   Washington,  D.C. 

4.  International  Commission  on  Radiological  Protection  (ICRP).    1991.   1990 
Recommendations  of  the  International  Commission  on  Radiological  Protection. 
ICRP  Publication  60.   Pergamon  Press.   Elmsford,  N.Y. 

5.  United  Nations  Scientific  Committee  on  the  Effects  of  Atomic  Radiation 
(UNSCEAR).   1988.   Sources,  Effects  and  Risks  of  Ionizing  Radiation.  United 
Nations.   New  York,  N.Y. 

6.  United  Nations  Scientific  Committee  on  the  Effects  of  Atomic  Radiation 
(UNSCEAR).   1986.   Genetic  and  Somatic  Effects  of  Ionizing  Radiation.  United 
Nations.   New  York,  N.Y. 

7.  United  States  Environmental  Protection  Agency.    1991.   National  Primary 
Drinking  Water  Regulations:  Radionuclides.   Federal  Register,  V.  56,  No.  138, 
July  18,  1991.   pp.  33050-33127. 

8.  World  Health  Organization.    1993.   Guidelines  for  Drinking  Water  Quality . 
Second  Edition.   World  Health  Organization,  Geneva.* 

These  reports  may  be  reviewed  at  the  following  locations: 

Advisory  Committee  on  Environmental  Clerks  Department 

Standards  Town  of  Ajax 

Library  65  Harwood  Avenue  South 

40  St  Clair  Ave.  W  Ajax,  Ontario 

Suite  401  LIS  2H8 

Toronto,  Ontario 

M4V  1M2 

For  further  information,  please  call  the  ACES  office  at  (416)  314-9265. 
*This  document  was  not  published  until  following  the  launch  of  the  public  consultation 
on  January  10,  1994.   The  draft  version  was  used  by  the  MOEE  in  the  development  of 
the  proposed  ODWO.   Copies  were  provided  by  ACES  at  the  above  listed  locations  with 
the  other  documents  for  review.  ~. 


Ontario 


Ministry 

of  the  •  •  .  ...  -.>_ 

Environment 

September  30,  1992 

FOR  FURTHER  INFORMATION: 

Elizabera  Janz  (416)  440-3479 
Environmental  Assessment  Branch 

Gerry  Merchant  (416)  323^333 
-     •  Public  Affairs  and 

'.  -  Communications  Services  Branch 

NEW  AJAX  WATER  SUPPLY  PLANT  TO  PROCEED 
-  ON  THE  BASIS  OF  CLASS  ENVIRONMENTAL  ASSESSMENT 

Environment  Minister  Ruth  Grier  today  announced  she  has  decided  not  to  require  an 
individual  environmental  assessment  of  the  proposed  water  supply  plant  in  Ajax.   The 
decision  is  subject  to  a  series  of  conditions  drawn  from  the  Environmental  Assessment 
Advisory  Committee's  (EAAQ  report  to  the  minister. 

"I  have  taken  steps  to  ensure  that  the  community  has  the  protection  it  needs  without 
unduly  delaying  completion  of  a  much-improved  and  needed  area  water  supply,"  Mrs.  Grier 
said.   "I  appreciate  the  concern  area  residents  have  about  the  potential  effects  of  nuclear  plant 
discharges  on  their  drinking  water  and  I  have  considered  their  comments  very  carefully." 

In  her  decision,  the  minister  considered  requests  from  the  public  that  the  project  be 
bumped-up  to  an  individual  environmental  assessment.  The  major  concerns  expressed  dealt 
with  the  plant's  location  on  the  waterfront  and  with  potential  tritium  levels  in  water  from  the 
plant  as  a  result  of  its  proximity  to  the  Pickering  Nuclear  Generating  Station. 

After  the  community's  bump-up  request  was  received  by  the  Minister,  she  asked 
EAAC  to  advise  her  on  whether  the  project  should  be  subject  to  a  full  environmental 
assessment.  The  advisory  committee  recommended  against  the  bump-up  if  a  series  of 

1/2...  27592.NR  ...•■■- 


rwtntDO* 
recyuh)  wen 

UàPQMt  KIW 


conditions  could  be  met  by  the  region.   They  also  advised  that  the  province   undertake  a  full 
review  of  Ontario's  standards  for  tritium. 

Mrs.  Grier  decided  to  address  public  concerns  about  tritium  by  referring  Ontario's 
standards  for  tritium  to  the  Advisory  Committee  on  Environmental  Standards  (ACES)  for 
public  review.  The  development  of  the  water  plant  will  be  allowed  to  proceed  while  this 
review  is  under  way. 

In  addition,  Mrs,  Grier  said  staff  of  the  ministry's  Environmental  Assessment  Branch 
will  be  consulting  Ontario  Hydro,  the  Atomic  Energy  Board  and  the  ministries  of  health, 
environment  and  energy  on  a  recommendation  by  EAAC  to  establish  a  Durham  Nuclear 
Health  Committee. 

Mrs.  Grier  agreed  with  EAAC  that  the  Regional  Municipality  of  Durham's  planning 
process  was  adequate  and  that  most  of  the. environmental  concerns  can  be  addressed  through 
appropriate  terms  and  conditions.   She  set  21  conditions  to  which  the  region  must  agree 
before  construction  on  the  new  plant  can  proceed. 


-30 


2/2...  27592.NR 

36 


Ministry  of  Environment  and  Energy 


Backgrounder  on  a  recommended  Interim 
Ontario  Drinking  Water  Objective  for  Tritium 


The  Ministry  of  Environment  and  Energy  is  recom- 
mending that  the  current  Ontario  Drinking  Water 
Objective  (ODWO)  for  tritium  of  40,000  becquerels 
per  litre  (Bq/L)  be  replaced  by  an  interim  Drinking 
Water  Objective  of  7,000  Bq/L  (a  becquerel  is  a  unit 
used  to  measure  radioactivity).  This  recommenda- 
tion is  based  on  a  reassessment  of  the  adverse 
human  health  effects  resulting  from  exposure  to 
radiation. 

Background: 

ODWOs  are  the  primary  tool  used  by  the  ministry  to 
ensure  the  acceptability  of  public  water  supplies. 
Achieving  drinking  water  objectives  ensures  aes- 
thetically pleasing  water  that  does  not  represent  any 
significant  risk  to  the  health  of  the  consumer. 

The  need  to  re-examine  the  basis  of  the  ODWO 
for  tritium  resulted  from  a  recommendation  of  the 
Environmental  Assessment  Advisory  Committee 
(EAAC)  concerning  the  new  Pickering/Ajax  water 
treatment  plant  proposed  by  the  Region  of  Durham. 
EAAC  advised  that  an  individual  environmental 
assessment  for  the  plant  was  not  necessary  provided 
that  certain  concerns  were  addressed.  One  of  these 
concerns  centred  on  the  levels  of  radioactive  sub- 
stances, specifically  tritium,  in  drinking  water. 

To  address  this  concern,  EAAC  recommended 
that  the  Minister  ask  the  Advisory  Committee  for 
Environmental  Standards  (ACES)  to  carry  out  a 
public  review  and  advise  on  an  appropriate  standard 
for  levels  of  tritium  in  drinking  water.  In  order  to 
conduct  this  review,  the  ministry  has  prepared  this 
backgrounder  as  a  general  introduction  to  the 
Rationale  Document  for  the  Development  of  an 
Interim  Ontario  Drinking  Water  Objective  for 
Tritium. 


Properties  of  tritium: 

Tritium  is  a  naturally  occurring,  radioactive  form  of 
hydrogen.  As  part  of  its  natural  decay,  tritium  emits 
radiation  which  is  relatively  weak,  compared  to  that 
emitted  from  other  radioactive  substances.  Neverthe- 
less, all  radiation  released  by  radioactive  substances 
is  considered  carcinogenic  in  humans;  the  risk  of 
developing  cancer  is  considered  to  be  proportional  to 
the  radiation  dose  received. 

The  most  common  form  of  tritium  is  tritiated 
water,  which  is  a  by-product  of  water-cooled  nuclear 
generating  stations  and  is  indistinguishable  in  terms 
of  taste,  smell  and  texture  from  normal  water. 
Human  exposureto  tritium  results  primarily  from 
ingestion  or  inhalation;  once  taken  in,  tritium  is 
distributed  rapidly  throughout  the  body. 

The  basis  for  the  revised  objective: 

The  revised  ODWO  for  tritium  is  based  upon  the 
recommendation  of  the  World  Health  Organization 
that  the  annual  "dose"  received  from  drinking  two 
litres  of  water  a  day  be  set  at  0.1  mSv  (1000  mSv  =  1 
sievert;  a  sievert  is  the  unit  used  to  measure  a  radio- 
active "dose").  The  recommended  "dose"  represents 
an  estimated  risk  of  five  cases  of  cancer  for  every 
million  people  exposed;  however,  that  figure  is  less 
than  five  per  cent  of  the  "dose"  attributable  to 
background  radiation.  The  revised  ODWO  of  7,000 
Bq/L  for  tritium  is  derived  by  converting  sieverts 
into  becquerels  using  an  appropriate  conversion 
-factor  for  tritium. 


-¥f- 


fSà  r\ 


4-,-s  ^    ^ 


Sources  of  exposure  to  radiation: 

Natural  sources  of  radiation,  such  as  cosmic  rays 
and  naturally  occurring  radioactive  substances, 
account  for  more  than  80  per  cent  of  an  individual's 
exposure  to  radiation.  Other  sources,  such  as  medi- 
cal X-rays,  account  for  approximately  11  to  15  per 
cent  of  annual  exposure.  Exposure  to  tritium  in 
drinking  water  generally  accounts  for  less  than  0.1 
per  cent  of  overall  annual  exposure. 

In  Ontario,  tritium  in  drinking  water  is  moni- 
tored under  the  Ontario  Drinking  Water  Surveil- 
lance Program  as  well  as  under  specific  surveillance 
programs  carried  out  in  the  vicinity  of  nuclear 
generating  stations.  Data  obtained  from  these 
programs  indicate  that  the  level  of  tritium  in  drink- 
ing water  in  Ontario  is  generally  very  low  and 
rarely  exceeds  100  Bq/L.  The  maximum  value 
recorded  in  1991  was  370  Bq/L  in  Petawawa. 

Application  of  the  0DW0  for  tritium: 

The  revised  drinking  water  objective  for  tritium 
applies  when  other  radioactive  substances  are  not 
present  in  the  water.  In  those  cases  where  more 
than  one  radioactive  substance  is  present  in  drink- 
ing water  supplies,  the  maximum  allowable  limit  for 
all  radioactive  substances  is  set  so  that  the  "dose" 
derived  from  all  radioactive  substances  in  the 
drinking  water  does  not  exceed  0.1  mSv. 

In  the  case  of  emergency  situations,  such  as  the 
spill  or  release  of  nuclear  material,  the  Nuclear 
Emergency  Plan  administered  by  the  Ministry  of 
Solicitor  General  applies.  In  such  situations,  advice 
is  sought  from  various  ministries  on  a  case-by  -case 
basis  as  to  an  appropriate  course  of  action.  For 
decisions  affecting  the  acceptability  of  drinking 
water  supplies,  the  objectives  for  all  radioactive 
substances,  including  tritium,  would  be  among  the 
factors  considered  when  arriving  at  an  appropriate 
decision. 

The  interim  ODWO  for  tritium  will  be  applied 
as  a  health-related  maximum  acceptable  concentra- 
tion and  will  be  reviewed  once  the  Canadian  Drink- 
ing Water  Guidelines  for  radioactive  substances  are 
revised. 


For  further  information: 

To  obtain  the  Rationale  Document  for  the 
Development  of  an  Interim  Drinking  Water  Objective 
for  Tritium  or  other  information  related  to  the 
proposed  review,  please  contact: 

Advisory  Committee  on 
Environmental  Standards 
40  St.  Clair  Ave.  W. 
Toronto,  Ont. 
M4V1M2 

Tel:  (416)  314-9265 


48- 


Appendix  2:   List  of  Respondents  in  ACES' s  Public  Consultation  on 

Tritium 


Members 

A.  Anderson 

M.E.  Anderson 
M.  Bednarz 
R.  Bell 

B.  Biederman 

C.B.  Bigham 

J.  Brackett/& 
I.  Kock 

K.  Brosemer 

P.  Brown 

W.F.M.  Brown 

E.  Burt 

G.  Colm 

W.  Cooney 

H.  Cross 

R.  Cuyler 

A.G.  Darnley 

E.  deQuehen 

C.  Duschenes 
M.J.  Diamond 
R.  Doomernik 


Ajax  Citizens  for  the  Environment,  Ajax,  Ontario 

Director  of  Public  Health  Inspection,  York  Region,  Newmarket, 
Ontario 

President,  The  Beaver  Valley  Heritage  Society,  Clarksburg,  Ontario 


C.  Bruce  Bigham  Consulting,  Deep  River,  Ontario 

Durham  Nuclear  Awareness,  Oshawa,  Ontario 
Clean  North,  Sault  Ste.  Marie 
Councillor,  Ward  5,  Town  of  Ajax,  Ajax,  Ontario 
Walter  Brown  Associates,  Mississauga,  Ontario 


International  Geochemical  Mapping,  Ottawa,  Ontario 
Northumberland  Environmental  Protection,  Northumberland,  Ontario 


Technical  Director,  Fasson  Canada  Inc.,  Ajax,  Ontario 
39 


F.  Eggert  & 
S.  Eggert 

V.E.  Emerson 

V.E.  Emerson 

H.  Emery 

I.  FairLie 

B.  Fergusson 

M.  Fisher 

J.  Foster 

R.  Frank 

J.C.  Fraser 


Pickering  beach  Residents'  Association,  Ajax,  Ontario 
President,  The  Brereton  Field  Naturalists'  Club 

The  Entry  Group,  Toronto,  Ontario 

Town  Engineer,  Town  of  Dryden,  Dryden,  Ontario 

Durham  Wetlands  and  Watersheds,  Oshawa,  Ontario 

Chairperson  of  the  Conservation  Committee  of  the  Guelph  Field 
Naturalists,  Guelph,  Ontario 

Manager,  Water  Quality,  Windsor  Utilities  Commission,  Windsor, 
Ontario 


D.  Golden-Rosenberg 

R.D.  Graham  Manager,  AECL  Research,  Chalk  River,  Ontario 

H.  Guttman  Chair,  American  Water  Works  Association,  Toronto,  Ontario 

K.  Hansenberger 

P.  Hartwig 

O.  Hendrickson 

H.  Henrikson 


D.  Hiner 
P.  Hutton 
J.  Jackson 
I.  Judah 
M.J.  Kern 


Community  Liaison  Group,  Deep  River,  Ontario 

Concerned  Citizens  of  Renfrew  County,  Ottawa,  Ontario 

President,  The  Little  Cataraqui  Environment  Association,  Kingston, 
Ontario 

Atikokan  Citizens  for  Nuclear  Responsibility,  Mattawa,  Ontario 

Conserver  Society  of  Hamilton  and  District  Inc.  Hamilton,  Ontario 

Citizens'  Network  on  Waste  Management,  Kitchener,  Ontario 

Enviro-Hai-Tech,  Montreal,  Québec 


40 


Z.  Kleinau 

I.  Kock 

S.  Leonhardt 

N.C.  Lind 
A.  Lovett 
C.W.  Lundy 

P.  Lush 

H.  MacDonald 

R.  Maclntyre 

A.  Macpherson 
R.  Maruska 

P.  Maslak 
J.  McEwan 
K.G.  McNeill 
C.  Mobbs 
D.K.  Myers 
P.C.  Nanda 
K.E.  Nash 

J.S.  Nathwani 

B.  NeU 

O.  Nigol 
N.  Parrott 


Bruce  Peninsula  Environment  Group,  Lions' s  Head,  Ontario 

Durham  Nuclear  Awareness,  Oshawa,  Ontario 

Pickering  Ajax  Citizen's  Together  For  The  Environment,  Pickering, 
Ontario 

Professor  Emeritus,  University  of  Waterloo,  Victoria,  B.C. 


Regional  Clerk,  The  Regional  Municipality  of  Durham,  Whitby, 
Ontario 


Sault  Area  Nuclear  Awareness,  Goulais  River,  Ontario 

Ontario  Hydro,  Toronto,  Ontario 

N.C.M.W.M.,  Grimsby,  Ontario 

Professor  Emeritus  of  Physics,  University  of  Toronto,  Toronto,  Ontario 


Consumers'  Association  of  Canada  (Windsor),  Kingsville,  Ontario 

Director,  Nuclear  Waste  and  Environment  Services,  Ontario  Hydro 
Nuclear,  Toronto, Ontario 

Joint  Committee  on  Health  and  Safety,  The  Royal  Society  of  Canada, 
The  Academy  of  Engineering,  Toronto,  Ontario 


41 


T.E.  Parry 

C.  Peabody 

B.  Pellier 

R.  Robinson 
N.  Rubin 

C.  Sauriol 
J.  Scott 
L.  Segatti 
L.R.  Silver 
H.B.  Stevens 

I.J.  Stuart-Sheppard 
J.E.  Taylor 
B.J.  Vandenhazel 
R.  Waterston 
B.  Willard 
S.  Willard 
R.S.  Wilson 
P.R.  Youakim 
J.  Young 


Director  of  Engineering,  Town  of  Whitchurch-Stouffville,  Stouffville, 
Ontario 


Chair,  Social  Action  Committee,  Unitarian  Congregation  of  South  Peel, 
Mississauga,  Ontario 

Ridgetown  Public  Utilities  Commission,  Ridgetown,  Ontario 

Energy  Probe  Research  Foundation,  Toronto,  Ontario 


Director,  Elgin  St.  Thomas  Health  Unit,  St.  Thomas,  Ontario 

Manager,  Albright  &  Wilson  Americas,  Dunnville,  Ontario 

Ajax  Save  the  Waterfront  Committee,  Ajax,  Ontario 
Black  Hackle  Engineering,  Toronto,  Ontario 
Technologist,  Environment  Canada,  Burlington,  Ontario 


42 


Appendix  3:   Summary  Tables  of  Public  Comments 


Please  Note:    ACES  has  endeavoured  to  present  comment  summaries  that  are  a  true 
reflection  of  the  content  and  context  of  the  responses  received.    Paraphrased  comments 
are  indicated  by  their  inclusion  in  square  brackets  ([  ]).     Complete  written 
submissions  are  available  for  public  review  at  the  ACES  office.    The  names  of 
respondents  not  representing  an  organization  have  been  removed  in  accordance  with 
the  Freedom  of  Information  and  Protection  of  Privacy  Act  requirements. 


43 


Comments  Regarding  the  Proposed  Level 

Support  no  change  from  40,000  Bq/L 


Name 


C.  Bruce  Bigham 
Consulting 
Deep  River,  Ont. 


The  Entry  Group 
Toronto,  Ont. 


Town  of  Dryden 
Dry  den,  Ont. 


Ridgetown  Public 
Utilities  Commission 
Ridgetown,  Ont. 


Comment 


To  answer  the  questions  in  your  ad  I  offer  the  following: 

1.  No 

2.  See  above  [description  of  exposures  from  air  travel,  living 
in  the  mountains  etc.,  also  the  "Perhaps  we  are  adapted  to 
higher  levels  and  actually  now  suffer  from  a  radiation 
deficiency."] 

3.  The  current  level  (40,000)  or  higher  depending  on  an 
economic  analysis. 


Leave  it  at  40,000  Bq/L  if  changing  the  standard  will  cost  the 
people  of  Ontario  one  red  cent  in  added  measuring 
equipment,  time  required  to  create  reports  or  creation  of 
committees  or  advertising  expenses  or  BUREAUCRACY. 


I  would  like  to  suggest  that  the  present  limits  are  low  enough 
and  dropping  them  represents  over-kill  and  as  such  a  cost  to 
the  country  and  to  the  environment.    ...the  present  standard  is 
amply  safe  and  no  reduction  is  warranted. 


In  a  day  of  increasing  burdens,  priority  in  the  use  of  the 
dollar  must  be  of  upmost  importance... I  would  request  that 
no  change  be  made  to  the  current  regulations  at  this  time. 


44 


Support  proposed  level 


Name 

Comment 

Individual 

The  proposed  standards  do  not  appear  to  have  a  negative 
impact  [socio-economically].    There  appears  to  be  no 
contraindication  to  the  reduction  from  40,000  Bq/L  to  7,000 
Bq/L  in  drinking  water. 

Fasson  Canada  Inc. 
Ajax,  Ont. 

No  issue  with  the  proposals  sent-support  both. 

The  Brereton  Field 
Naturalists'  Club 
Barrie,  Ont. 

...agree  with  the  proposed  reduction  of  allowable  parts  per 
unit.    We  would  urge  the  Ontario  government  to  revise  the 
standards. 

AECL  Research 

Chalk  River  Laboratories 

Chalk  River,  Ont. 

...the  proposed  Interim  [ODWO]  for  tritium  of  7000  Bq/L  to 
be  generally  within  the  range  of  what  would  be  an  acceptable 
standard,  provided  it  is  applied  in  the  intended  manner:  that 
is  as  an  upper  limit  of  acceptability  for  lifelong 
consumption.... AECL  Research  would  strongly  encourage 
ACES  to  recommend  that  Ontario  adopt  the  revised  CDWG 
standards  once  they  are  issued. 

The  Little  Cataraqui 
Environment  Association 
Kingston,  Ont. 

We  strongly  support  the  proposed  reduction  from  40,000 
Bq/L.... even  at  7,000  Bq/L... the  risk  of  cancer  increases  by 
5  cases  per  million,  which  we  believe  should  be  the 
maximum  acceptable... 

Atikokan  Citizens  for 
Nuclear  Responsibility 
Mattawa,  Ont. 

The  Ministry  is  to  be  commended  for  their  suggestion  the 
interim  objective  be  lowered.    It's  a  step  in  the  right 
direction. 

Conserver  Society  of 
Hamilton  and  District 
Inc. 
Hamilton,  Ont. 

I  feel  from  reading  the  brief  information  that  even  the  new 
standard  really  isn't  that  useful  in  the  general  context,  but 
would  be  an  acceptable  overall  standard. 

Individual 

I  agree  that  the  proposed  criterion  of  7000  Bq/L  has  been 
determined  using  conservative  reasoning  and  available 
science. 

Fisons  Instruments  Inc. 
Ottawa,  Ont. 

These  levels  are  acceptable 

Durham  Region 
Whitby,  Ont. 

. .  .the  Health  and  Social  Services  Committee  of  Regional 
Council  considered  the  [ODWO  for  tritium]  and  ...adopted 
the  following  recommendations  of  Committee:  that  the 
proposed  interim  Ontario  Drinking  Water  Objective  for 
tritium  be  endorsed;... 

45 


Ontario  Hydro 
Toronto,  Ont. 

Ontario  Hydro  is  prepared  to  accept  the  recommendations  of 
the  international  scientific  community.    We  believe  that  at 
7,000  Bq/L,  the  Drinking  Water  Objective  provides  a  good 
measure  of  protection  and  can  be  applied  practically  as 
recommended  by  the  World  Health  Organization. 

Ontario  Hydro  Nuclear 
Toronto,  Ont. 

...Ontario  Hydro  supports  the  proposed  interim  level  of  7,000 
Bq/L  for  the  drinking  water  objective  for  tritium. 

Individual 

I  wish  to  record  my  support  of  a  value  of  7000  Bq/L  for  the 
interim  ODWO  for  tritium. 

Individual 

The  proposed  [standard]  is  acceptable  if  it  reduces  the  level 
of  contamination  to  the  lowest  level  possible. 

Albright  and  Wilson 
Americas 
Dunnville,  Ont. 

We  agree  with  these  new  maximum  proposed  standards.    We 
would  also  like  to  commend  the  process  being  used  to  bring 
about  the  changes. 

Black  Hackle  Engineering 
Toronto,  Ont. 

This  letter  is  to  confirm  support  for  the  proposed 
changes... The  7000  Bq/L  (or  lower)  limit  should  be  adopted 
not  from  a  health  perspective,  but  from  a  safety  perspective 
to  ensure  that  tritium  sources  are  properly  controlled. 

Environment  Canada 
Burlington,  Ont. 

The  proposed  standards  are  acceptable.    However,  I  would 
like  to  suggest  a  reduction  in  levels  with  2  sets  of  values  in 
mind  and  2  target  dates  say  in  1995  and  the  year  2002. 

46 


US  level 


Name 

Comment 

Windsor  Utilities 
Commission 
Windsor,  Ont. 

...would  encourage  the  ODWO  be  further  reduced  and 
conform  with  the  U.S.  EPA  proposed  tritium  limit  in  dw  of 
800  Bq/L. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

We  strongly  feel  that  even  the  7000  Bq/L  limit  is 
unacceptable  and  that  this  limit  should  be  brought  down  to  at 
least  the  U.S.  EPA  reading. 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

Since  the  lake  waters  are  used  by  nuclear  plants  in  USA  and 
Canada,  it  would  be  advisable  for  both  countries  to  consider 
harmonization  of  standards.    It  may  be  relevant  to  note  that 
current  USA  standards  are  set  at  much  lower  levels  than  the 
proposed  ACES  standards. 

Individual 

...there  is  no  economic  reason  for  setting  a  tritium  limit 
...any  higher  than  approximately  500  Bq\L.    In  order  to  have 
consistency  with  U.S.,  I  would  like  to  suggest  that  a  limit  of 
800  Bq\L  be  adopted  at  this  time. 

Individual 

...adhere  to  dw  stds  that  are  as  stringent  as  those  in  the 
United  States  or  better. 

Individual 

...my  body  is  not  more  resilient  to  tritium  than  our 
neighbours  to  the  south.    Their  level  is  a  far  cry  from  our 
existing  Ontario  level  of  40,000  Bq/L.    Additionally, 
Americans  restrict  construction  within  five  miles  of  a  nuclear 
plant,  let  alone  building  a  water  treatment  plant. 

Individual 

A  further  lowering  of  the  level  to  at  least  the  U.S.  level 
currently  proposed  i.e.  2300  per  litre. 

47 


Standard  should  be  set  at  background  level 


Name 

Comment 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

...an  appropriate  drinking  water  standard  for  tritium  should 
be  set  at  current  background  levels...  bet  ween  5  and  10  Bq/L, 
and  falling,  so  drinking  water  standards  should  tighten  over 
time  to  reflect  the  decay  of  tritium  from  weapons  testing. 

Clean  North 

Sault  Ste.  Marie,  Ont. 

[The  standard  should  be  set  at  less  than  10  Bq/L,  depending 
on  location]. 

Individual 

Drinking  water  from  WSP  located  less  than  ten  kilometres 
from  a  NGS  shall  provide  drinking  water  with  a  maximum 
tritium  level  of  8.7  Bq/L.    For  all  other  WSPs  the  maximum 
amount  allowed  shall  not  exceed  300  Bq/L. 

Durham  Wetlands  and 
Watersheds 
Oshawa,  Ont. 

...we  want  a  Permanent  Ontario  Drinking  Water  Objective  of 
10  Bq/L  and  anything  more  is  unacceptable... 

Pickering  Ajax  Citizen's 
Together  for  the 
Environment 
Pickering,  Ont. 

The  interim  level  for  tritium  should  be  set  at  5  to  10  Bq/L 
until  all  information  is  gathered. 

Individual 

Commitment  to  zero  tolerance  of  any  levels  of  tritium  above 
background  levels  must  be  a  priority... In  addition,  for  any 
level  of  tritium  above  background  levels,  I  feel  the  public 
should  be  advised. 

Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont. 

...we  recommend  that  the  std  set  by  the  MOEE  should  be  8.7 
Bq/L,  which  is  reasonable  and  doable. 

48 


Zero  discharge 


Name 

Comment 

Individual 

Any  levels  of  tritium  are  totally  unacceptable  to  me.    Pure 
water  is  basic  to  good  health. 

Individual 

Tritium  should  not  be  allowed  in  our  drinking  water. 

Individual 

As  with  the  regulation  of  most  other  hazardous  materials, 
tritium  should  be  subjected  to  ZERO  DISCHARGE 
objectives. 

Individual 

The  proposed  standard  is  not  acceptable,  it  is  too  high. 
Preferably  it  should  be  zero. 

Individual 

If  one  molecule  of  a  substance  can  destroy  or  change  forever 
one  cell  then  we  recommend  that  a  "zero"  tolerance  level  be 
permitted  and  that  a  "zero"  input  standard  be  put  in  place. 

Individual 

I  believe  it  is  obvious  that  no  toxic  substance  ought  to  be 
permitted  to  accumulate  in  our  environment.    There  is  no 
suitable  alternative. 

Conservation  Committee 
Guelph  Field  Naturalists 
Guelph,  Ont. 

It  is  our  understanding  that  the  two  Federal  Governments 
around  the  Great  Lakes  are  committed  to  zero  discharge;  why 
is  this  not  the  case? 

Individual 

...recommend  zero  tolerance  of  toxic  materials  in  drinking 
water. . .  [discussion  of  LFC  virtual  elimination 
recommendations] 

Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

In  its  Seventh  Biennial  Report  on  Great  Lakes  Water  Quality, 
the  IJC  recommends  that  the  "Governments  incorporate  those 
radionuclides  which  meet  the  definition  of  persistent  toxic 
substances  in  their  strategy  for  virtual  elimination."   We  ask 
the  province  to  therefore  immediately  begin  to  develop  a 
strategy  for  eliminating  the  presence  of  tritium  in  water  as  a 
result  of  human  activities. 

Individual 

No  level  above  zero  discharge  is  acceptable... Production  and 
release  of  tritium  at  any  level  should  be  eliminated. 

Sault  Area  Nuclear 
Awareness 
Goulais  River,  Ont. 

...drinking  water  standards  should  reflect  an  attitude  of  zero 
tolerance  of  all  toxic  materials. 

Individual 

I  understand  any  contamination  from  a  nuclear  plant  is  only 
acceptable  at  the  level  of  NIL. 

Individual 

If  it  was  not  there  in  before  then  keep  it  out  period... not  try 
to  tell  people  x%  is  OK  when  you  don't  know. 

49 


Individual 

It  is  our  considered  opinion  that  the  only  "safe"  level  of 
tritium  in  drinking  water  is  zero... 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

The  Consumer  Association  of  Canada  commends  the  step 
towards  the  number  of  becquerels  from  70,000  to  7,000  but 
would  recommend  ACES  that  it  set  further  lower  limits 
towards  a  zero  tolerance. 

Social  Action  Committee 
Unitarian  Congregation 
of  South  Peel 
Mississauga,  Ont. 

...it  is  our  contention  that  NO  tritium  should  be  allowed  in 
our  drinking  water.    Only  ZERO  tritium  is  acceptable. 

Individual 

...this  committee  owes  it  to  my  family  and  the  other  families 
in  Ajax  and  Pickering  to  recommend  a  zero  level  of  tritium. 

Individual 

My  ideal  standard  for  radiation  in  my  drinking  water  is  0 
Bq/L. 

Individual 

Economic  considerations  should  not  override  ecological 
concerns... I  therefore  recommend  that  the  Ajax  water  plant 
either  will  not  proceed  or  be  prevented  from  releasing 
tritium. 

Individual 

We  propose  a  level  of  0  Bq/L... the  objective  that  you 
recommend  to  the  MOEE  should  be  0  Bq/L,  to  honour  your 
mandate  to  provide  a  reference  level  based  only  on  health 
considerations. 

Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont. 

...the  Ontario  Drinking  Water  Objective  for  tritium  in 
drinking  water  should  be  0  Becquerels/Litre.    This 
"objective"  reflects  what  is  desirable,  based  solely  on  health 
considerations,  and  is  a  "reference  level".    That  is  the 
objective  we  urge  you  to  recommend  to  the  MOEE,  in 
accordance  with  your  mandate,    [go  on  to  recommend  a 
"standard"  of  8.7  Bq/L] 

Individual 

...I  must  insist  that  the  only  "sound,  practical  standard"  for 
radionuclides  in  water  is  zero.    How  long  will  the  nuclear 
industry  be  given  to  meet  the  new  objective  of  0  Bq/L? 

50 


Recommended  level  other  than  proposed,  US,  background  or  zero. 


Name 

Comment 

Individual 

Drinking  water  from  WSPs  located  less  than  ten  km  from  a 
NGS  shall  provide  drinking  water  with  a  max.  level  of  8.7 
Bq/L,  for  all  other  WSPs  the  max.  allowed  shall  not  exceed 
300  Bq/L.    Rationale  is  as  follows:  in  the  vicinity  of  a  NGS 
the  max.  acceptable  level  shall  not  exceed  background  level 
found  in  Lake  Ont.    Elsewhere  the  allowable  limit  shall  not 
exceed  300  Bq/L  which  is  a  reasonable  standard  to  live  with. 

Individual 

It  is  my  considered  opinion  that  a  reduction  in  the  permissible 
limits  of  tritium  (and  any  other  radioactive  material)  in 
drinking  water  should  be  made  as  low  as  is  possible 
(unmeasurable?). 

Concerned  Citizens  of 
Renfrew  County 
Ottawa,  Ont. 

The  goal  should  be  zero  discharge  for  cmpds  such  as  tritium 
that  are  known  carcinogens.    Recognizing  that  it  will  take 
time  to  achieve  this  goal,  we  recommend  that  interim  stds 
.achieve  at  least  a  100  fold  reduction  in  the  max.  allowable 
tritium  concentration  in  dw,  i.e.,  from  the  current  40,000  to 
less  than  400  Bq/L. 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

...set  the  ODWO...at  a  level  in  the  range  of  10  to  30  Bq/L, 
if  not  lower. 

Individual 

I  suggest  that  the  "As  Low  as  Reasonably  Achievable" 
requirement  also  be  added  to  the  new  standard. 

Individual 

...if  the  objective  was  set  at  100  Bq/L  then  on  the  rare 
occasions  when  it's  exceeded  enforcement  should  result  in  the 
necessary  steps  being  taken  to  correct  the  problem  at  the 
sources. 

Town  of  Whitchurch- 
Stouffville 
Stouffville,  Ont. 

...allowable  limits  should  be  set  much  lower  to  ensure  health 
protection... only  naturally  occurring  tritium  need  be 
considered  in  the  100  Bq/L  range. 

51 


Exposure 

Basis  of  cancer  risk  calculation  by  WHO,  ICRP  etc. 


Name 

Comment 

Individual 

Applying  the  most  recent  dose  to  risk  relationships  published 
by  the  ICRP... the  additional  risk  of  serious  radiation  induced 
disease  will  be  around  5  per  million  per  year  or  about  1  in 
3000  per  lifetime.    Risks  of  this  magnitude  ...are 
acceptable... 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

...several  references  [in  the  transcripts]  to  cancer  risks  to 
people  "exposed  over  a  lifetime"  should  refer  to  fatal  cancer 
risks  over  a  lifetime  from  exposure  over  only  a  single  year. 

52 


2  litre  drinking  water  consumption  level 


Name 

Comment 

American  Water  Works 
Association 
Toronto,  Ont. 

The  Interim  Objective  calculation  uses  an  annual  consumption 
factor  assuming  2  L/day.    Almost  all  other  objectives  in  the 
ODWO  are  based  on  a  70  kg  person  consuming  1.5  litres  of 
water  per  day  over  70  years.    The  document  should  outline 
the  justification  for  varying  from  the  norm  when  setting 
drinking  water  objectives. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

We  feel  that  the  2  1  consumption  factor  is  too  conservative  as 
DW  is  consumed  as  ingredient  in  cooking,  baking,  steaming, 
soft  drinks,  beer  and  other  beverages. 

53 


Risk 

Historical  risk  assessment  by  international  agencies 


Name 

Comment 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

The  MOEE  rationale  document  on  tritium  standards  in  dw 
adopts,  without  question,  the  position  of  international 
agencies  which  have  historically  underestimated  the  risks  of 
radiation  exposure. 

Individual 

The  rationale  document  relies  entirely  on  information 
generated  by  both  the  EPA  and  the  WHO.    The  latter  uses 
data  based  on  studies  of  survivors  of  the  atomic  blasts  in 
Hiroshima  and  Nagasaki .    Interestingly , ...  the  maximum 
allowable  dose  has  been  reduced  from  0.5  mSv  down  to  0.1 
mSv.    Does  this  mean  in  another  13  years  it  will  again  be 
reduced? 

Individual 

Outline  in  their  comments  suspicion  of  any  groups  ability  to 
assess  the  impact  of  tritium  in  drinking  water  due  to  historical 
view  of  radiation  exposure,  i.e.,  X-rays  in  the  1930s;  atomic 
bomb  tests  in  the  1940s  etc. 

Individual 

Since  for  many  decades,  scientists  have  been  underestimating 
the  risks  associated  with  radiation  exposure  and  our 
understanding  of  radioactive  substances  is  not  yet  complete, 
how  can  we  be  sure  what  exactly  an  appropriate  margin  of 
safety  is  when  calculating  life  time  exposures? 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

The  official  sources  of  the  risk  coefficients  for  radiation 

carcinogenesis  the  underlie  the  proposed 

ODWO... have... consistently  underestimated  the  actual 

effectiveness  of  radiation  at  causing  cancer.    There  is  no 

scientific  or  political  reason  to  assume  this  has  ended. .  .What 

is  clear  is  that  believing  yesterday's... was  not  adequately 

prudent. 

Individual 

Are  we  supposed  to  be  reassured  by  the  fact  that  these  groups 
of  experts  all  were  wrong  by  a  factor  of  5  between  1980  and 
1993?   What  reassurances  do  we  have  that  they  are  now 
right? 

54 


Acceptability  of  cancer  risk 


Name 

Comment 

Ontario  Section 
American  Water  Works 
Association 
Toronto,  Ont. 

The  rationale  document  cites  the  calculated  cancer  risk  as  5 
fatal  cancers  per  1  million  people  exposed.    A  conservative 
public  health  approach  is  to  use  a  cancer  risk  level  of  1  in  1 
million  over  a  70  year  lifetime. 

Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

Additional  cancer  risk  of  five  in  one  million  is  an 
unacceptably  high  additional  cancer  risk.    For  example,  the 
City  of  Toronto  has  set  one  in  a  million  as  the  highest 
acceptable  additional  cancer  risk. 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

...we  know  of  no  reason  to  believe  that... an  additional  five- 
per-million  risk  of  fatal  cancer  [is]  an  acceptable  risk  from 
one  single  contaminant  in  one  year's  drinking  water.    A 
lifetime  of  that  exposure  would  present  a  300  per  million  total 
additional  risk  of  fatal  cancer,  and  approx.  a  750  per  million 
total  additional  risk  of  non-fatal  cancer. 

55 


Additional  Sources  of  Uncertainty 

Sensitive  Populations 


Name 

Comment 

Clean  North 

Sault  Ste.  Marie,  Ont. 

[Susceptible  populations  need  to  be  considered  in  risk 
assessment.    Developmental  effects  are  an  issue.] 

Individual 

We  request  that  in  setting  stds  the  Committee  adopt  a  std 
which  takes  into  consideration  the  effect  on  a  developing 
fetus. 

Individual 

Medical  research  seems  to  have  found  that  small  children 
living  down  wind  from  a  "Station"  show  a  far  greater  risk  of 
attracting  LEUKAEMIA. 

Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

We  find  it  disturbing  to  compare  sources  of  radiation  and  say 
that  tritium  intake  as  a  result  of  drinking  water  generally 
accounts  for  less  than  0.1  %  of  overall  exposure.    It  isn't 
general  exposure  that  matters  most.    Standards  must  be  set 
for  those  people  who  are  subject  to  the  highest  exposures  and 
receive  the  higher  than  average  intake  because  of  drinking 
water. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

Risk  assessment  does  not  take  into  account  that  children  have 
a  much  smaller  ratio  of  body  weight  to  water  and  food 
intake.    They  also  have  a  much  higher  rate  of  metabolism. 
Children  would  be  at  a  much  higher  than  the  5  fatal  cancers 
per  million  population.    They  would  also  have  a  longer 
exposure  time  than  adults... radiation  accumulates  in  the  body 
over  a  lifetime. 

Individual 

I  am  particularly  interested  in  potential  impacts  as  they  relate 
to  children,  and  women-particularly  women  in  their  child 
bearing  years. 

Individual 

Ingestion  rates  and  dose  conversion  factors  for  infants  and 
children  are  age-dependent,  therefore  the  dose  to  tritium  in 
dw  relationship  may  be  different  to  that  of  adults.   I  believe 
this  should  be  addressed. 

Individual 

. . .  [although  this  may  appear  to  be  a  safe  level  for  an 
adult]... due  to  the  physiological  changes  occurring  within  a 
growing  child,  that  may  not  be  an  appropriate  exposure  and 
thus  would  be  exposing  children  to  a  greater  risk  than 
assumed.    Also,  no  listed  comparison  was  made  with  regard 
to  a  fetus  or  a  pregnant  woman... 

56 


Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

[Concerns  raised  over  exposure  in  pregnant  women  and  the 
effects  to  the  ova  of  her  female  fetus... i.e.,  the  fetus'  ova 
incorporate  tritiated  hydrogen  which  then  decays  over  the 
next  12  to  25  years,  damaging  the  surrounding  genetic 
material  and  resulting  in  birth  defects  in  her  offspring] 

Individual 

It  has  been  well  established  that  young  children,  foetuses,  and 
even  the  "stem  cells"... are  more  vulnerable  to  various  toxins 
than  are  healthy  adults,  because  their  cells  are  dividing  much 
more  rapidly. 

Individual 

We  understand  that  the  risk  assessments  for  the  proposed  stds 
are  based  on  "kilogram  per  body  weight".  Which  body 
weight  have  you  used?  Is  it  the  155  lb.  male? 

Individual 

The  myth  is  that  "One  standard  fits  all".    The  reality  is  that 
"Standards  for  adults  may  be  100  to  1000  times  too  high  for 
fetuses" . 

57 


Concerns  re:  long  term  low  level  radiation  exposure 


Name 

Comment 

Ajax  Citizens  for  the 
Environment 
Ajax,  Ont. 

We  believe  there  should  be  testing  done  on  the  long  term, 
low  level,  cumulative  effects  of  tritium  in  drinking  water,  and 
new  acceptable  levels  determined. 

Individual 

[The  ODWO  is  based  on]  a  radiation  dose  external  to  the 
body.    The  effects  of  long  term  low  level  tritium  ingested  in 
the  dw,  although  not  known  at  this  time,  are  in  all  likelihood 
much  more  severe  than  that  due  to  external  radiation. 

Individual 

We  are  still  not  sure  of  the  long  term  effects  of  low  level 
radiation. 

Individual 

...how  can  the  long  term  health  effects  from  a  life  of 
drinking  slightly  tritiated  water  be  deduced  from  studies  of  A- 
bomb  victims? 

58 


Advisory  level 


Name 

Comment 

Individual 

We  urge  that  nothing  above  background  levels  be  tolerated 
without  a  public  advisory  being  given. 

AECL  Research 

Chalk  River  Laboratories 

Chalk  River,  Ont. 

[An  advisory  level]  appears  to  be  contrary  to  the  stated 
purpose  and  application  of  ODWO's  and  CDWG's... There 
appears  to  be  no  real  reason  to  single  out  tritium  in  the 
province-wide  ODWO's  for  special  treatment  which  is  not 
given  to  other  health-related  parameters.    One  alternative 
...might  be  for  municipal  authorities  in  communities  which 
express  significant  concern  about  water  quality  to  routinely 
issue  data  directly  to  the  public  (e.g.  though  newspapers)  on 
concentrations  in  [dw]  of  all  health  related  parameters, 
including  tritium,  in  comparison  to  their  respective  limits. 
Any  such  special  provisions  should  be  established  as  needed, 
and  should  not  be  established  as  Province-wide  requirements 
in  the  ODWO's. 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

...two  action  levels  should  be  set  for  tritium  in  drinking 
water.    The  first  action  level  should  be  set  near  normal 
background  levels,  and  if  that  level  is  exceeded,  a  public 
advisory  should  be  provided  to  allow  people  to  make  the 
choice  of  not  drinking  tap  water.    A  second  action  level 
should  be  set  which  would  trigger  the  shutdown  of  the  water 
supply  plant  and  a  temporary  shift  to  alternative  water 
sources. 

Individual 

Commitment  to  zero  tolerance  of  any  levels  of  tritium  above 
background  levels  must  be  a  priority... In  addition,  for  any 
level  of  tritium  above  background  levels,  I  feel  the  public 
should  be  advised. 

Sault  Area  Nuclear 
Awareness 
Goulais  River,  Ont. 

The  proposed  standard  of  7,000  Bq/L  is  too  high,  considering 
that  the  present  background  levels  of  tritium  in  the  Great 
Lakes  are  less  than  10  Bq/L.    Any  alternative  levels  beyond 
background  levels  should  not  be  accepted  without  a  full 
public  advisory  being  given. 

Individual 

...I  shudder  to  think  of  the  spills  we  do  not  hear  about, 
[could  be  interpreted  as  rec.  for  spills  advisory?] 

Ontario  Hydro  Nuclear 
Toronto,  Ont. 

We  also  support  the  method  of  application  of  the  [dw] 
objective  recommended  by  the  [WHO]... and  [MOEE]...a 
single  action  level  where  the  situation  is  to  be  investigated 
and  further  possible  action  considered  when  concentrations 
reach  100%  of  the  objective. 

59 


Sunsetting 


Name 

Comment 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

...an  appropriate  drinking  water  standard  for  tritium  should 
be  set  at  current  background  levels... between  5  and  10  Bq/L, 
and  falling,  so  drinking  water  standards  should  tighten  over 
time  to  reflect  the  decay  of  tritium  from  weapons  testing. 

Individual 

. .  .phaseout  and  cut  off  deadlines  and  timetables  reflecting  the 
current  serious  situation  of  tritium  and  other  radionuclide 
emissions. 

Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

In  its  Seventh  Biennial  Report  on  Great  Lakes  Water  Quality, 
the  IJC  recommends  that  the  "Governments  incorporate  those 
radionuclides  which  meet  the  defmition  of  persistent  toxic 
substances  in  their  strategy  for  virtual  elimination.  "   We  ask 
the  province  to  therefore  immediately  begin  to  develop  a 
strategy  for  eliminating  the  presence  of  tritium  in  water  as  a 
result  of  human  activities.    This  strategy  should  include 
.precise  time  lines. 

Individual 

What  is  needed  is  a  phase  out  of  polluting  industries,  clean 
up  and  rehabilitation  programs,  with  an  objective  of 
eliminating  man  made  contaminants  from  our 
environment... [the  standard]  should  be  reviewed  yearly  to 
reduce  it  even  further. 

Environment  Canada 
Burlington,  Ont. 

I  would  like  to  suggest  a  reduction  in  levels  with  2  sets  of 
values  in  mind  and  2  target  dates  say  in  1995  and  the  year 
2002. 

60 


Synergistic  or  additive  effects 


Name 

Comment 

Individual 

Mixed  with  other  chemicals,  taken  up  by  foliage,  soil,  plants 
and  animals  it  becomes  part  of  our  food  chain. 

Individual 

...the  combined  affect  of  all  pollutants  in  our  drinking  water 
remains  to  be  unknown.    In  my  opinion  the  focus  should  be: 
...  3.  Combined  effects  of  all  pollutants. 

The  Little  Cataraqui 
Environment  Association 
Kingston,  Ont. 

...cancer  incidence  increases  by  5  cases  per  million,  which 
we  believe  should  be  at  least  the  maximum  acceptable, 
bearing  in  mind  that  this  is  just  one  of  many  chemicals  that 
increase  cancer  rates. 

Citizen's  Network  on 
Waste  Management 
Kitchener,  Ont. 

The  use  of  risk  numbers  to  justify  accepting  a  contaminant  in 
water  does  not  take  into  account  the  cumulative  impact  of  the 
various  sources  of  contaminants  in  our 
environment... [example  given  hypothesizing  number  of 
chemicals  in  evn.  110,000  and  number  that  cause  cancer 
5,500;]  If  each  of  those  chemicals  contributes  a  1  in  100,000 
risk,  that's  a  final  risk  of  1  in  20,000.    According  to  present 
day  de  minimus  standards,  that's  neither  negligible  nor 
acceptable. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ontario 

Risk  assessments  target  only  the  effects  of  one  specific  toxic 
chemical  on  human  health  but  there  is  growing  evidence  that 
chemicals  are  entering  into  combinations  with  other 
substances  with  unknown  effects  on  humans. 

Individual 

[reasons  for  finding  std  unacceptable]... how  these  unknowns 
will  react  with  other  chemicals  already  present  or  yet  to  be 
developed. 

Individual 

Issues  which  I  feel  must  be  addressed  include:  ...the 
synergistic  effects  of  tritium  and  (other  radioactive  water) 
released  by  PNGS  combined  with  Ontario  Hydro's  tritium 
removal  facility  at  the  DNGS  and  that  which  is  released  into 
the  Great  Lakes  by  other  facilities  (e.g.,  Detroit  Edison) 
relative  to  the  many  hundreds  of  toxins  in  the  environment. . . 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

...tritium  is  absorbed  by  the  human  body  directly  from  the 
environment  and  is  likely  to  produce  stochastic  effects 
(comprising  malignant  and  hereditary  diseases)  simply  or  as 
synergistic  effect  along  with  other  radioactive  particles  like 
Cesium  137,  Iodine  131,  Radium  226,  and  Strontium  90. 

61 


Social  Action  Committee 
Unitarian  Congregation 
of  South  Peel 
Mississauga,  Ont. 

We  are  advised  there  are  other  radioactive  substances  in  the 
drinking  water  as  well  as  other  toxic  material.    Only  ZERO 
tritium  is  acceptable. 

Individual 

My  second  concern  is  the  combination  of  tritium  with  other 
toxic  chemicals  in  the  lake... I  would  like  ACES  to  look  into 
this  or  recommend  that  it  be  further  explored  by  the 
appropriate  agencies. 

Individual 

["The  experts"]  have  not  looked  at  the  synergistic  effect  of 
tritium  with  other  pollutants. 

62 


Other  routes  of  exposure 


Name 

Comments 

Individual 

It  [tritium]  can  be  ingested  through  the  consumption  of 
tritiated  water  as  well  as  directly  through  the  skin. 

Individual 

...whilst  ingestion  is  a  major  pathway,  inhalation  and  skin 
absorption  will  also  play  a  part.   I  estimate  that  domestic 
showering  and  bathing  could  contribute  an  additional  1  or  2 
percent  of  dose  and  that  inhalation  and  skin  absorption  of 
tritium  form  indoor  air  whose  humidity  is  partly  evaporated 
tap  water  could  contribute  an  additional  5  to  20  percent.   In 
deriving  a  water  quality  objective,  I  believe  these  additional 
pathways  should  be  acknowledged. 

Town  of  Whitchurch- 
Stouffville 
Stouffville,  Ont. 

My  feeling  is  that  I  would  not  want  to  bathe  a  sick  baby, 
possibly  with  a  skin  rash,  in  water  with  a  7000  Bq/L  standard 
nor  would  I  want  my  children  to  drink  or  swim  etc.  in  such 
water. 

[Quoting  from  Wang,  Willis,  and  Loveland,  1975]  Deposition 
of  radioisotopes  within  the  body... poses  an  entirely  different 
problem.  In  this  case,  isotopes  whose  radiation  have  very 
short  ranges  are  the  most  hazardous  for  they  dissipate  all 
their  energy  with  a  very  restricted  volume  of  tissue.  Thus 
alpha  emitters  and  weak  beta  (tritium  type)  emitters  present 
the  greatest  hazard... 

Individual 

...I  use  drinking  water  for  bathing,  and  we  know  tritium  is 
absorbed  through  the  skin.    I  also  cook  my  food  in  the  water, 
I  swim  in  my  pool  in  the  summer,  I  water  my  vegetable 
garden  with  the  water,  and  so  on... we  are  also  exposed  to 
high  levels  of  ground  tritium  and  air-borne  tritium. 

63 


Bioaccumulation 


Name 

Comment 

Individual 

[in  reasons  for  finding  std  unacceptable]... how  they  will 
accumulate  in  the  ecosystem,  including  humans. 

Individual 

...the  half  life  of  tritium  is  12.3  years  and  is  thus  capable  of 
bioaccumulation  in  our  ecosystems. 

64 


Organically  bound  tritium 


Name 

Comment 

Individual 
London,  UK 
on  behalf  of 
Northumberland 
Environmental  Protection 

Chronic  exposures  to  raised  concentrations  of  [tritium  in 
drinking  water  and  air-borne  tritium]  may  result  in 
organically  bound  tritium  building  up  in  the  food  chain  to 
ambient  HTO  levels,  and  in  OBT  contaminated  food  grown 
near  the  nuclear  facilities  being  eaten.    The  ingestion  of  OBT 
is  widely  recognised  as  being  more  hazardous  than  the 
ingestion  of  HTO... "the  radiation  dose  delivered  to  specific 
tissues,  for  example  bone  marrow,  may  be  greater  following 
the  ingestion  of  OBT  by  almost  an  order  of  magnitude  as 
compared  to  HTO" .    It  is  recommended  that  studies  be 
carried  out  to  ensure  that  food  grown  near  nuclear  facilities  is 
not  consumed  nor  used  as  feedstuff  s ,  and  to  ascertain  the 
levels  of  OBT  in  residents  near  nuclear  facilities. 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

...the  tritium  in  these  organic  compounds  is  much  more  [toxic 
and  carcinogenic  than  tritiated  water]because  it  is  much  more 
likely  to  incorporate  itself  into  the  molecular  structure  of  our 
DNA,  our  proteins,  fats  and  carbohydrates... 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

...tritium  can  also  become  organically  bound  to  molecules  in 
the  body,  and  this  can  result  in  a  much  longer  biological  half- 
life. 

65 


RBE  of  Tritium 


Name 

Comment 

Individual 
London,  UK 
on  behalf  of 
Northumberland 
Environmental  Protection 

The  Quality  factor,  recently  reconfigured  approximately  to 
the  radiation  weighting  factor,  for  tritium  remains  at  1 , 
although  considerable  radiobiological  evidence  exists  that  it 
should  be  increased  to  2  and  perhaps  higher.    The 
evidence... of  increasing  RBEs  with  decreasing  doses  of 
tritium  is  particularly  worrying. 

Environmental  Protection 

Branch 

AECL  Research 

Chalk  River  Laboratories 

Chalk  River,  Ont. 

The  RBE... is  not  a  number  carved  in  stone  but  can  vary 
appreciably  depending  on  the  system  and  the  endpoint 
studied.    A  high  value  in  one  particular  system  does  not 
negate,  or  even  contradict,  a  lower  value  obtained  in  another 
system.    The  RBE  of  a  given  radiation  is  the  ratio  of  the  dose 
of  the  reference  radiation  required  to  produce  a  given  level  of 
effect  divided  by  the  dose  of  the  test  radiation  required  to 
produce  the  same  level  of  effect.    If  tritium  was  more 
effective,  the  denominator  would  be  smaller  than  the 
numerator;  a  RBE  >  1  would  result.    The  international 
standard  for  the  reference  radiation  is  200-250  kVp  X-rays. 
At  low  doses  and  dose  rates  (and  protracted  exposures), 
however,  operation  of  an  X-ray  machine  is  difficult  and  Co60 
gamma  rays  are  often  employed... Considerable  evidence 
exists  that  the  RBE  for  gamma  rays  referenced  to  X  rays 
becomes  <  1  for  low  dose/low  dose  rate  exposure;  ...This 
means  that  if  tritium  beta  rays  were,  in  fact,  materially 
indistinguishable  in  effect  from  X-rays,  the  beta  rays  would 
appear  to  have  RBE  >  1  in  reference  to  the  gamma  rays... an 
apparent  high  RBE  (value  >  1)  can  result  because  the 
numerator  is  higher  not  because  the  denominator  is  lower 
(which  would  be  the  situation  if  the  test  radiation  was  more 
effective,  as  a  lower  dose  would  suffice).    This  view  is  borne 
out  by  a  review  of  the  AECB's  Advisory  Committee  on 
Radiation  Protection  :  "Observed  RBE  values  at  low  doses 
and  low  dose-rates  are  usually  about  2  to  3  when  tritium  beta 
rays  are  compared  to  cobalt  60  gamma  rays  but  are  closer  to 
1  to  2  when  compared  to  200  kVp  X-rays.    This  conclusion 
is  supported  by  microdosimetric  considerations  of  the  quality 
of  tritium  beta  rays,  cobalt  60  gamma  rays  and  X-rays." 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

Cell  and  animal  experiments  indicate  that  the  RBE  value  for 
tritium  should  be  at  least  2,  and  that  it  may  be  as  high  as  5, 
depending  on  which  type  of  effect  is  being  considered.    This 
means  that  tritium  is  likely  2  to  5  times  more  hazardous  than 
is  currently  accepted  by  the  ICRP. 

66 


Dose  conversion  factor 


Name 

Comment 

Individual 
London,  UK 
on  behalf  of 
Northumberland 
Environmental  Protection 

...tritium's  internal  doses  may  be  underestimated  in  three 
ways.    These  are  the  use  of  a  unconservative  dose  conversion 
factors;  the  use  of  incorrect  metabolic  models  which  ignore 
organically  bound  tritium;  and  the  use  of  an  incorrect  Q 
factor  from  radiobiological  evidence... To  be  conservative,  the 
dose  factor  for  HTO  should  be  increased  at  least  to  the  higher 
values  in  the  US  [US  Nuclear  Regulatory  Commission  uses  a 
dose  conversion  factor  of  3.4  x  10-11  Sv/Bq  for  ingestion  and 
2.2  for  inhalation;  US  National  Council  on  Radiation 
Protection  and  Measurements  uses  2.4] 

Environmental  Protection 

Branch 

AECL  Research 

Chalk  River  Laboratories 

Chalk  River,  Ont. 

...calculate  the  ODWO  on  the  basis  of  the  primary  dose 
conversion  factor  value,  rather  than  on  the  basis  of  a 
secondary  value  calculated  form  the  dose  conversion  factor 
and  already  rounded.    This  would  give  a  value  of  7600  Bq/L 
as  noted  in  [the  Rationale  Document],  which  could  be 
rounded  to  8,000  Bq/L  if  desired. 

67 


Health  effects  other  than  cancer 


Name 

Comment 

Individual 

With  cancer  and  birth  defects  rampant,  we  need  to  clean  up 
our  Great  Lakes  and  not  add  to  the  toxins  already  there. 

Clean  North 

Sault  Ste.  Marie,  Ont. 

[MOEE  considered  only  fatal  cancer,  other  endpoints  are 
very  important,  such  as  immune  effects,  lupus,  crones, 
arthritis,  etc.    Morbidity  must  be  considered,  health  is  more 
than  the  absence  of  death.] 

Individual 

The  only  effect  mentioned  in  the  report  is  cancer.    What 
about  other  effects  such  as  old  age  diseases?   The  effects  are 
insidious  and  concerned  that  a  generation  of  people  are  being 
produced  with  an  impaired  ability  to  cope. 

Individual 
London,  UK 
on  behalf  of 
Northumberland 
Environmental  Protection 

...concern  has  been  expressed  about  tritium  doses  near 
DNA... tritium  from  tritiated  food  is  capable  of  entering  the 
DNA  molecule... the  same  is  true  from  chrome  tritiated  water 
ingestion... Another  key  point  in  the  possibility  of  high  pulses 
of  tritiated  water  resulting  in  the  transient  ingestion  of  high 
levels  of  HTO...Commerford  et  al  1982,  found  after  a 
transient  HTO  exposure  in  mice,  all  the  tritium  remaining  8 
weeks  post  exposure  was  bound  to  DNA  and  its  histonc.The 
half  lives  they  found  for  DNA  were  extremely  long... This 
has  implications  for  the  diets  of  pregnant  women  living  near 
nuclear  reactors  discharging  large  quantities  of  tritiated  water 
and  water  vapour. 

Durham  Wetlands  and 
Watersheds 
Oshawa,  Ont. 

Recent  studies  suggest  correlations  between  higher 
background  radiation  in  [dw]  and  problems  such  as  cancers, 
birth  defects,  mental  abnormalities  and  genetic  defects. 

Individual 
Toronto,  Ont. 

...radioactivity  in  the  body  increases  the  risk  of  developing 
cancer,  other  health  problems  associated  with  immune 
deficiency  as  well  as  birth  defects. 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

the  "end  point"  of  interest  should  not  be  just  death  from 
cancer.    The  dose  of  radiation  that  causes  other  health 
impacts,  such  as  birth  defects,  should  be  considered  as  well. 

Individual 

...what  kind  of  baseline  health  analysis  has  been  conducted 
with  regard  to  human  health  impacts  of  tritium  in  this  area?   I 
refer  not  only  to  fatal  cancers,  but  also  to  other  impacts, 
including  such  things  as  respiratory  illness,  sex  organs  of 
males  and  females,  fetal  impact,  etc. 

68 


Sault  Area  Nuclear 
Awareness 
Goulais  River,  Ont. 

All  exposure  to  radioactivity  increases  the  risks  of  developing 
cancer,  and  accompanying  health  problems.    The  cumulative 
effects  on  descendant  generations  is  highly  debated  by 
industry,  but  has  been  proven  to  include  birth  defects  and 
sterility. 

Individual 

We  see  the  Mongoloid  children  with  their  parents,  or 
sometimes  in  groups  in  the  mall.    Our  daughter  in  law  had 
cancer  but  was  operated  on  successfully.    She  is  only  36  and 
does  not  drink  nor  smoke. 

Individual 

[someone  raised  to  this  person  that  Dr.  Petkau's  work  came 
up  at  the  deputation  session]  Most  other  international 
scientists  in  radiation  protection  have  in  recent  years  agreed 
that  Dr.  Petkau's  studies  are  not  directly  relevant  to  presumed 
effects  of  radiation  on  living  organisms  and  have  pursued 
other  lines  of  research. 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

...tritium  is  absorbed  by  the  human  body  directly  from  the 
environment  and  is  likely  to  produce  stochastic  effects 
(comprising  malignant  and  hereditary  diseases)  simply  or  as 
synergistic  effect  along  with  other  radioactive  particles... 

Further  quantitative  estimates  of  the  number  of  genetic 
defects  produced  in  the  human  population  are  usually  arrived 
at  by  estimating  the  proportion  of  individuals  affected  per 
dose  in  fruit  flies  or  mice  and  extrapolating  the  results  to 
humans.  This  imparts  considerable  uncertainties  to  the 
results. 

Town  of  Whitchurch- 
Stouffville 
Stouffville,  Ont. 

In  addition  to  the  five  cancer  deaths/million  which  in  itself 
must  only  be  a  statistical  estimate,  what  about  the  other 
illnesses  precipitated  by  tritiated  water.   Was  that  factored 
into  the  five  year  death  figure  or  ignored? 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

...it  would  appear  prudent  to  assume  that  tritium-apparently 
the  health  dominant  emission  from  those  stations-is  implicated 
[in  the  excesses  of  Down's  syndrome  and  childhood 
leukaemia  near  Pickering  and  Bruce] 

The  risk  estimates  on  which  the  ODWO  is  based  assume, 
contractually,  that  cancer  is  the  only  unfortunate  health 
effect  of  consuming  tritium... and  that  tritium  is  the  only 
radionuclide  (if  not  even  the  only  carcinogen)  in  drinking 
water. 

69 


Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont 

Concerns  raised  regarding  incidence  in  Ajax/Pickering  area 

of  as  outlined  in  AECB  studies: 

Down's  Syndrome  (86%  higher); 

five  other  infant  abnormalities  25%  to  71%  higher: 

limb  reduction  abnormalities; 

ear,  face,  and  neck  abnormalities; 

urinary  system  abnor.; 

circulatory  system  abnor.; 

ventricular  system  abnor; 

infant  death  rates  (2  to  5  times  higher); 

childhood  leukaemia  deaths  (34%  higher) 

childhood  leukaemia  (34%  higher); 

damage  to  the  immune  system  and  genetic  damage  caused  by 

free  radicals; 

rate  of  prostate  cancer  in  men. 

Individual 

[concerns  expressed  about  incidence  of  Down's  syndrome, 
birth  defects,  infant  standardized  mortality  ratios  etc.  in  the 
Pickering/ Ajax  area] 

[Proposes  a  supralinear  dose  response  curve,  with  greater 
effects  at  lower  doses  than  a  linear  curve  would  predict; 
outlines  "The  Petkau  Effect"]A  protracted  exposure  to 
ingested  beta  emitters  may  be  1 .000  times  more  harmful  to 
cell  membranes  than  a  brief  exposure  to  X-rays.    The  longer 
the  exposure,  the  smaller  the  dose  needed  to  damage  cells. 

70 


Feasibility 
Cost  Analysis 


Name 

Comment 

Individual 

[raises  questions  regarding  the  changes  proposed  and  whether 
they  would  have  a  significant  reduction  in  pollution  given 
what  the  economic  costs  may  be.]   In  this  day  and  age  of 
cutbacks  and  economic  uncertainty  in  the  future,  is  what  we 
are  doing  going  to  be  seen  as  another  barrier  to  business? 

C.  Bruce  Bigham 
Consulting 
Deep  River,  Ont. 

...the  most  difficult  thing  was  obtaining  a  reasonable  balance 
between  safety  measure  implementation  and  cost.    So  my 
major  comment  on  the  proposal  is  that  I  feel  this  has  not  been 
studied  adequately.    It  should  not  be  'beyond  the  scope'  as 
stated  in  Section  10.   It  is  a  critical  issue. 

American  Water  Works 
Association 
Toronto,  Ont. 

all  reasonable  efforts  to  improve  drinking  water  quality  and  to 
set  drinking  water  standards  based  on  a  balanced  evaluation 
of  documented  health  effects  research,  demonstrated 
treatment  techniques,  and  cost  considerations. 

Individual 

No  one  can  answer  this  question  (is  7000  acceptable?) 
without  having  considered... what  are  the  costs?  and  what  are 
the  expected  benefits?  If  your  government  has  not  demanded 
that  you  provide  a  documented  risk-benefit  analysis  with  your 
recommendation  it  is  behind  the  times.... Your  advertisement 
should  have  read  "This  std  is  expected  to  cost  Ontario 
households  $xx  per  year  net  but  will  prevent  initiation  of  an 
estimated  yy  fatal  cancers  per  year.   Is  that  acceptable?"   I 
hope  that  the  Minister  will  feel  obliged  to  provide  such  cost- 
effectiveness  information  when  the  standard  is  imposed. 

Ontario  Hydro 
Toronto,  Ont. 

The  public  must  be  aware  of  the  costs  and  benefits  of  this 
guideline,    [outlines  the  hypothetical  costs  and  benefits  of  a 
water  plant  closure  if  level  reaches  7,000  for  one 
week]... then  the  benefit  would  be  to  have  prevented  the 
public  from  receiving  a  dose  of  approximately  1.8  uSv....And 
what  is  the  cost  to  society?  If  an  emergency  is  declared  the 
cost  of  activating  the  emergency  plan  will  be  quite 
substantial.    Furthermore  the  public  becomes  concerned  about 
the  quality  of  their  drinking  water.   Some  may  purchase 
bottled  water.    Some  may  suffer  anxiety.    If  Water  Supply 
Plants  are  shutdown,  the  public  will  be  directly  affected. 
They  may  go  without  water.    These  costs  are  real. 

71 


Joint  Committee  on 
Health  and  Safety 
The  Royal  Society  of 
Canada 
Toronto,  Ont. 


The  first  principle  is  that  risks  shall  be  managed  to  maximize 
the  total  expected  net  benefit  to  society... The  goal  of  any  risk 
mitigation  effort  ought  to  be  the  maximization  of  the  net 
benefit  to  society  in  terms  of  the  length   of  healthful  life  for 
all  members  at  all  ages... we  would  appreciate  receiving  the 
studies  that  the  regulator  has  performed  that  would  show  that 
the  detriments,  in  terms  of  public  health  impact,  arising  from 
current  levels  of  tritium  are  unacceptable... We  also  note  that 
reducing  low  levels  of  risk  is  expensive.    Often,  the  societal 
costs  for  reducing  small  risks  to  an  even  lower  level  can  be 
disproportionately  high  in  relation  to  the  benefit  to  be  gained, 
[enclosed  Health  and  Safety  Policies:  Guiding  Principals  for 
Risk  Management  booklet] 


72 


Water  Treatment  and  Location  of  Drinking  Water  Plants 


Name 

Comment 

Individual 

...I  am  really  concerned  about  the  levels  of  tritium  in  our 
drinking  water... I  hope  the  result  [of  the  consultation]  will  be 
such  sound  advice  from  the  ACES  Committee  to  the 
Minister... that  they  will  insist  on  the  plant  being  moved  to  a 
safer  location. 

Pickering  Beach 
Residents'  Association 
Ajax,  Ont. 

We  urge  you  in  your  advisory  capacity  to  the  government  to 
insist  on  a  safer  location  for  this  proposed  water  supply  plant. 

American  Water  Works 
Association 
Toronto,  Ont. 

...given  that  there  is  no  treatment  it  may  be  more  critical  to 
control  discharges  of  tritium  into  the  source  water. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

There  is  not... a  choice  available  when  it  comes  to  drinking 
water:  it  is  clearly  stated  that  tritium  contained  in  water 
cannot  be  readily  distinguished... it  also  states  that 
conventional  treatment  is  believed  to  be  of  limited 
effectiveness  for  the  removal  of  tritium. 

Individual 

We  were  very  surprised  at  the  information  presented  to  you 
(at  the  Feb.  16,  1994  deputation)  particularly  the  fact  that 
tritium  is  in  our  drinking  water,  cannot  be  filtered  or  boiled 
out  and  that  there  are  substantial  differences  in  "safe" 
levels. . . 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

Whatever  tritium  level  is  drawn  by  intake  pipes  of  water 
purification  plants  are  supplied  to  consumers  in  their  homes. 

Individual 

...with  no  proven  method  of  eliminating  or  filtering  tritium 
from  water  sources  it  makes  enormous  sense  to  prevent  the 
problem  in  the  first  place. 

Town  of  Whitchurch- 
Stouffville 
Stouffville,  Ont. 

We  should  strive  to  minimize  the  health  risk  by  removing  the 
source  of  higher  levels  of  tritium  or  locating  water  supplies 
that  meet  the  existing  levels. 

Individual 

A  direction  for  the  building  of  NEW  water  supply  plants  to 
accept  sites  with  the  best  probability  of  meeting  a  tritium 
level  of  2300  Bq/L. 

73 


Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont. 


...we  also  encourage  ACES  to  recommend  to  the  MOEE  that 
no  new  water  supply  plant  be  constructed  within  5  miles  of  a 
nuclear  generating  station,  which  is  the  law  in  the  United 
States. 


74 


Implementation 

Jurisdiction/Multiple  water  based  standards 


Name 

Comment 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

...the  Seventh  Biennial  Report  of  the  International  Joint 
Commission  recommends  that  governments  incorporate 
radionuclides  in  their  strategy  for  virtual  elimination.    This 
means  that  tritium  pollution  must  stop. 

Clean  North 

Sault  Ste.  Marie,  Ont. 

[TJC  has  named  tritium  as  a  persistent  toxin  and  therefore  a 
candidate  for  zero  discharge] 

Individual 

In  my  opinion  the  focus  should  be:  ...  1.  the  allowable 
tritium  releases  to  water  by  Ontario  Hydro. 

Individual 

The  recent  International  Joint  Commission  (UC)  report 
recommended  that  governments  work  towards  the  elimination 
of  any  radionuclides  with  a  half  life  greater  than  six  months. 
The  half  life  of  tritium  is  12.3  years  -  24  times  longer  than 
the  UC  recommendation. 

Durham  Wetlands  and 
Watersheds 
Oshawa,  Ont. 

The  [TJC]  has  stated  that  only  a  zero  tolerance  level  of 
additional  tritium  in  the  [dw]  of  the  Great  Lakes  is 
acceptable. 

Ontario  Hydro  Nuclear 
Toronto,  Ont. 

It  should  also  be  noted  that  the  AECB  operating  licenses 
specify  that  the  nuclear  station  must  also  comply  wiht  all 
applicable  provincial  and  local  regulations.    This  implies  that 
we  must  comply  with  the  most  restrictive  regulations  in  cases 
where  there  is  overlap  of  jurisdiction. 

American  Water  Works 
Association 
Toronto,  Ont. 

...given  that  there  is  no  treatment  it  may  be  more  critical  to 
control  discharges  of  tritium  into  the  source  water. 

Atikokan  Citizens  for 
Nuclear  Responsibility 
Mattawa,  Ont. 

Cynical  persons,  myself  included,  could  come  to  the 
conclusion  that  the  MOEE  are  using  an  attempt  at  usurping 
the  AECB' s  efforts  to  set  stds  as  a  strategy  to  conflict  as 
many  jurisdictional  layers  of  government  as  possible.    These 
jurisdictional  conflicts  effectively  make  any  court  challenges 
as  difficult,  lengthy  and  expensive  as  possible.    The  MOEE 
must  forswear  their  old  trick  of  using  blurred  jurisdictional 
lines  between  the  Provincial  government  and  the  Federal 
government  to  excuse  inaction  or  indifference. 

75 


Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

In  its  Seventh  Biennial  Report  on  Great  Lakes  Water  Quality, 
the  IJC  recommends  that  the  "Governments  incorporate  those 
radionuclides  which  meet  the  definition  of  persistent  toxic 
substances  in  their  strategy  for  virtual  elimination."    We  ask 
the  province  therefore  immediately  begin  to  develop  a 
strategy  for  eliminating  the  presence  of  tritium  in  water  as  a 
result  of  human  activities. 

Individual 

...substantial  differences  in  "safe"  levels,  depending  on  which 
side  of  the  fence  one  is  situated,  i.e.,  AECL  has  adopted 
210,000  Bq/L  whereas  our  neighbours  to  the  South  have  700 
Bq/L. 

Individual 

One  of  the  most  baffling  aspects  of  standards  for  tritium  in 
drinking  water  is  their  proliferation  and  range.    We  have 
identified  at  least  7  tritium  concentration  "limits",  expressed 
in  Becquerels  per  litre  that  are  variously  quoted.... Which  one 
is  "safe"?  Are  any?   Will  a  new  ODWO  interim  standard 
make  any  difference  to  the  other  limits? 

Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont. 

The  IJC  is  about  to  include  radionuclides  with  a  half  life 
greater  than  6  months  to  their  list  of  "persistent  toxic 
substances".    The  half  life  of  tritium  is  12.3  years.    It 
qualifies  as  a  persistent  toxic  substance,  and  standards  must 
limit  our  exposure  to  it. 

[Other  discussions  re:  IJC' s  "Precautionary  Principle"  and 
"Principle  of  Reverse  Onus".] 

76 


Monitoring 


Name 

Comment 

Windsor  Utilities 
Commission 
Windsor,  Ont. 

...we  suggest  that  continuous  monitoring  be  instituted  and 
guidelines  established  to  prevent  ingress  of  highly 
contaminated  water  into  the  Great  Lakes  system. 

Individual 

[The  report  says  that  the]  "Procedure  for  determination  of 
tritium  in  water  begins  with  distillation  of  the  samples.  "   Is 
this  a  fair  test?  My  understanding  is  that  distilling  the  water 
removes  a  degree  of  tritium  from  the  water-is  this  the  way  to 
do  the  test? 

Individual 

Ont.  Hydro  has  still  not  developed  a  three  dimensional 
dispersion  model... and  as  such  no  predictable  pattern  of 
tritium  dispersion  can  be  evolved  which  will  enable  credible 
sampling  or  tracking.  No  current  reliable  on  line  monitor  for 
tritium  is  available  and  development  is  still  a  long  way  off. 
This  status  is  even  more  significant  since  we  are  building  a 
New  Water  Treatment  Plant  on  the  Ajax  waterfront,  some  4- 
5  km  from  the  PNGS  discharge. 

Elgin  St.  Thomas  Health 

Unit 

St.  Thomas,  Ont. 

Although  we  have  no  comment  on  the  specific  standards 
being  proposed,  we  believe  it  is  important  that  measurable 
and  meaningful  levels  should  be  established  for  any  material 
found  in  drinking  water  which  may  adversely  effect  public 
health. 

77 


Transboundry  sources 


Name 

Comment 

Conservation  Committee 
Guelph  Field  Naturalists 
Guelph,  Ont. 

...there  are  several  plants  on  the  US  side  doing  the  same 
[releasing  radioactive  emissions] 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

Just  think  what  a  child  born  in  1993  would  ingest  with  higher 
and  higher  concentrations  of  tritium  laced  water,  especially  if 
fate  has  put  it  in  the  Windsor-Detroit  region  where  Detroit 
Edison's  Ferme  nuclear  plant  is  starting  to  dump  millions  of 
litres  of  tritium  laced  water  on  a  regular  basis  to  Lake  Eri.e. 

Consumers'  Association 
of  Canada  (Windsor) 
Kingsville,  Ont. 

Since  the  lake  waters  are  used  by  nuclear  plants  in  USA  and 
Canada,  it  would  be  advisable  for  both  countries  to  consider 
harmonization  of  standards. 

78 


Enforcement 


Name 

Comment 

Atikokan  Citizens  for 
Nuclear  Responsibility 
Mattawa,  Ont. 

Enforcement  of  future  and  present  laws  must  be  credible  and 
rational.    Leave  industrial  development  schemes,  political 
hand-outs  and  jurisdictional  disputes  OUT  of  the  picture. 
The  FUNDS  for  strict  enforcement  and  compliance  should  be 
derived  from  the  costs  of  producing  nuclear  electricity. 

Individual 

Also,  improved  objectives  need  to  be  accompanied  by  strict 
enforcement.   I  believe  citizens  are  tired  of  ineffective 
'guidelines'  and  press  releases  stating  "no  immediate  health 
threat  to  the  public",  meanwhile  the  multitudes  of  cancer  are 
increasing. 

79 


Need  For  Additional  Health  Studies 

Need  for  additional  studies 


Name 

Comment 

Individual 

While  a  public  review  is  laudable,  the  lack  of  research  as  to 
low  level  exposure  to  radionuclides  and  its  sudden  elevated 
levels  in  drinking  water,  I  find  to  be  quite  distressing.    In  my 
opinion  the  focus  should  be:  ...  2.  the  effects  of  low  level 
tritium  exposure  to  the  populace.    While  I  understand  that 
such  studies  will  have  a  huge  cost  and  will  certainly  not  be 
completed  overnight,  their  implementation  are  long  overdue. 

American  Water  Works 
Association 
Toronto,  Ont. 

Although  supporting  data  indicate  that  reported  tritium  levels 
in  Ont.  drinking  water  are  extremely  low,  the  Section  advises 
that  additional  data  would  provide  background  levels  for  all 
areas  of  the  province. 

Energy  Probe  Research 
Foundation 
Toronto,  Ont. 

ACES  should... use  its  present  mandate  to  conduct  an 
investigation  of  the  phenomenon  of  a  short  term  tritium  pulse 
in  dw  consumed  by  a  pregnant  mother  being  incorporated  in 
the  ova  of  her  female  child. 

Ajax  Save  the  Waterfront 

Committee 

Ajax,  Ont. 

These  three  studies  [AECB  Down  Syndrome  etc,  AECB 
Leukaemia,  Great  Lakes  Health  Effects  Program:  Prostate 
Cancer]  show  that  there  is  an  abnormally  high  incidence  of 
health  problems  in  the  Pickering/ Ajax  area.    We  question  if 
this  is  just  a  coincidence,  or  can  be  dismissed  as  just 
statistical  aberrations.    Where  are  the  independent  studies  to 
explain  these  occurrences  in  our  area? 

Individual 

...there  is  little  reliable  information  available  on  the  effects  of 
many  forms  of  radiation,  of  various  strengths,  affecting 
various  parts  of  the  body.    Only  the  government,  which  has 
supported  the  nuclear  industry  form  its  inception,  and  has 
promoted  it  at  every  opportunity,  has  the  funding  to  do 
conduct  the  necessary  comprehensive  studies  to  obtain  such 
information  and...  has  refused  to  do  so... 

80 


Other  Comments  and  Recommendations 


Name 

Comment 

The  Beaver  Valley 
Heritage  Society 
Clarksburg,  Ont. 

Although  we  are  interested  in  water  quality,  we  have  no 
expertise  in  the  chemical  arena  and  therefore  are  unable  to 
contribute  to  your  consultation. 

York  Region  Public 
Health  Department 
Newmarket,  Ont. 

...while  we  consider  upgrading  of  stds  to  be  beneficial  our 
technical  knowledge... limits  our  capacity  to  suggest  alternate 
levels. 

Ajax  Citizens  for  the 
Environment 
Ajax,  Ont. 

...we  are  requesting  a  full  tritium  review  before  the  new 
Water  Treatment  Plant  planned  for  Ajax  is  underway. 

Clean  North 

Sault  Ste.  Marie,  Ont. 

[The  Backgrounder  refers  to  a  "recommended  dose",  this  is 
misleading  because  it  makes  it  sound  as  though  radiation  is 
beneficial,  like  recommended  daily  vitamin  intake.    Dose 
represents  five  fatal  cancers,  that  should  be  clear  in  the 
backgrounder.] 

Walter  Brown  Associates 
Environmental  Planners 
and  Consultants 
Mississauga,  Ont. 

A  general  comment  is  the  proposed  ODWO  is  an  exercise  in 

futility  because: 

a)Ont  Hydro  is  the  only  source  of  tritium... only  in 

conjunction  with  a  spill... at  $300/kg  Hydro  is  not  likely  to 

have  many  spills 

b)lakes  have  a  large  dilution  factor 

c)bkgd  levels  have  not  been  factored  in. 

Individual 

I  suggested  it  would  be  useful  to  obtain  information  about 
standards  or  guidelines  used  in  other  Western  countries,  such 
as  the  U.K.,  France  or  Germany,  and  the  rationale  for  these. 
...I  expect  ACES  will  have  taken  appropriate  action  to  obtain 
this  type  of  information  for  themselves. 

Northumberland 
Environmental  Protection 

We  are  therefore  formally  requesting  that  the  ACES 
Committee  recommend  to  the  government  that  a  full  review 
process  be  set  up... 

International  Geochemical 

Mapping  Project 

c/o  Geological  Survey  of 

Canada 

Ottawa,  Ont. 

...until  the  natural  variations  are  properly  established  by 
systematic  mapping  there  is  a  serious  risk  that 
administratively  prescribed  limits  for  "contaminants"  may  be 
unrealistic  and  could  cause  unnecessary  alarm,  litigation,  and 
economically  damaging  consequences. 

Individual 

...you  as  a  government  will  have  to  believe  both  sides  [one 
saying  there  is  no  problem,  the  other  saying  there  is]  and  take 
a  middle  viewpoint  of  both.    Do  not  trust  one  or  the  other, 
not  either  or. 

81 


Conservation  Committee 
Guelph  Field  Naturalists 
Guelph,  Ont. 

[concerns  re:ecosystem  effects]... many  wildlife  have  to 
survive  in  this  water  year  round. 

American  Water  Works 
Association 
Toronto,  Ont. 

where  decisions  regarding  resource  use  and  resource 
development  include  alternatives  adversely  affecting  the 
quality  of  the  drinking  water  supply  sources,  preference 
should  be  given  to  the  alternatives  that  protect  or  enhance  the 
quality  of  the  protected  source. 

Community  Liaison 

Group 

Siting  Task  Force 

Low  Level  Radioactive 

Waste  Management 

Deep  River,  Ont. 

We  cannot  provide  comments  or  recommendations  on 
environmental  issues  as  it  is  not  in  our  mandate  to  do  so.    We 
cannot,  therefore,  assist  you  in  this  review. 

Citizens'  Network  on 
Waste  Management 
Kitchener,  Ont. 

We  find  it  disturbing  to  compare  sources  of  radiation  and  say 
that  tritium  intake  accounts  for  less  than  0.1%  of  overall 
exposure.    It  isn't  general  exposure  that  matters  most.    Stds 
must  be  set  for  those  who  are  subject  to  the  highest  exposures 
and  receive  higher  than  average  intake... We  can't  do  much 
about  the  natural  sources.   Therefore  we  must  focus  on  those 
things  we  can  do  something  about. 

Individual 

[following  some  criticisms  of  the  document]  I  respectfully 
suggest  that  future  Rationale  Documents  used  by  ACES 
follow  a  specific  format  which  includes:  a  statement  of  the 
population  of  concern,  a  definition  of  the  critical  endpoint, 
and  the  calculation  of  the  criterion.    This  would  make  the 
review  of  the  document  easier  to  do. 

Bruce  Peninsula 
Environment  Group 
Lion's  Head,  Ont. 

We  also  strongly  urge  ACES  to  expand  their  advisory  activity 
in  taking  a  stand  on  eliminating  all  sources  of  tritium 
emission,  most  notably  the  aging  nuclear  reactors  which 
should  be  taken  out  of  service  at  the  earliest  possible  date, 
seeing  that  there  is  overcapacity  at  Ontario  Hydro. 

Durham  Nuclear 
Awareness 
Oshawa,  Ont. 

We  would  like  to  recommend  that  ACES  contact  an 
independent  expert  for  an  opinion  on  suitable  dose  conversion 
factors,... 

Ontario  Hydro 
Toronto,  Ont. 

...the  drinking  water  objective  must  be  used  appropriately,  in 
a  fashion  which  represents  true  impact.    ...This  is  our  main 
concern:  What  use  will  be  made  of  the  drinking  water 
objective?  The  rationale  document  quotes  on  page  14  exactly 
how  the  international  scientific  community  intended  this 
objective  to  be  used... The  [WHO  recommended]  that  the 
level  be  used  as  a  trigger  to  initiate  further  investigations. 

82 


University  of  Toronto 
Toronto,  Ont. 


[recommends  clarification  in  wording  of  Rationale  Document 
re:  consumption  level  and  duration  and  dose  as  well  as 
spelling  and  grammatical  errors]  I  have  no  objection  to  the 
WHO  guidelines  nor  the  Canadian  or  Ontario  equivalents  and 
can  only  emphasize  that  they  must  be  applied  rationally. 


Individual 


...the  release  of  tritium  into  the  natural  environment  will 
indeed  impact  other  life  forms... minimizing  tritium  could  be 
very  significant  for  entire  ecosystems... 

[Comparisons  with  background-2  concerns]...  1.  the  date  on 
which  natural  bkgd  was  determined  [should  be  pre-nuclear]  2. 
[thinning  of  the  ozone  may  create  more  tritium  in  the  upper 
atmosphere] 

Bkgd  tritium  as  a  beta  particle  is  incapable  of  penetrating  the 
outer  layer  of  skin  but  tritiated  drinking  water  is  uniformly 
distributed  among  all  of  the  soft  tissues  of  the  body.   Is  this 
not  a  potentially  greater  threat?        


Energy  Probe  Research 
Foundation 
Toronto,  Ont. 


[recommendations  for  emission  controls  e.g.  via  BAT  or 
BATEA  instead  of  ODWO]  1.  ACES  should  urge  the 
Minister  to  begin  treating  tritium  as  a  priority 
pollutant... either  by  adding  it  to  the  Emissions  Monitoring 
Priority  Pollutants  List  and  monitoring  and  controlling  it 
under  MISA  regulations,  or  by  adding  it  to  the  Candidate 
Substances  List  for  Bans  or  Phase  Outs.    In  our  view... either 
of  these  outcomes  would  be  more  appropriate  and  more 
beneficial... than  any  attempt  to  control  human  ingestion 
solely  through  an  ODWO. 

4.  In  its  report  to  the  Minister  ACES  should  endeavour  to 
correct  the  many  false  and  misleading  statements  in  the  Rat. 
Doc,  and  should  attempt  to  ensure  [it  is  circulated] 
From  March  10,  1994  submission:  inclusion  of  tritium  in 
Ontario's  Effluent  Monitoring  Priority  Pollutants  List  (of 
which  radionuclides  are  expressly  excluded)  and/or  Candidate 
Substances  List  for  Bans  or  Phase-Outs.    [Comparisons  of 
acceptable  risk  level  from  ACES' s  recommendations  re: 
NDMA  and  tritium  risk  levels]  ACES  should  not  adopt  a 
double  standard  of  acceptable  risk. 


General  support  of  increasing  water  quality;  interested  in  the 
designation  of  springs  as  heritage  sites. 


Individual 


83 


Pickering  Ajax  Citizen's 
Together  for  the 
Environment 
Pickering,  Ont. 

1 .  We  feel  that  the  tritium  issue  deserves  a  thorough 
investigation,  and  that  participant  funding,  and  if  warranted, 
intravenor  funding  be  made  available  to  all  parties. 

2.  The  ACES  report  should  be  distributed  to  the  public  on 
the  same  day  the  Minister  receives  his  copy,  and  that  the 
minister  review  this  report  within  a  reasonable  period  of 
time. 

Individual 

feels  that  setting  standards  based  on  risk  assessment  is  not 
sound  and  provides  a  rationalization  to  continue  to  produce 
tritium,  keep  people  employed  etc.  Any  risk  analysis  is  not 
worth  it 

Individual 

There  appears  to  be  no  known  rationales  for  tritium  targets  of 
allowable  levels,  be  it  40,000  Bq/L,  7,000  Bq/L  or  the  U.S. 
of  2,300  Bq/L. 

84 


Appendix  4:    Letter  from  Dr.  Waight,  Health  Canada 


FACSIMILE  MESSAGE/BELINO 

RADIATION  PROTECTION  BUREAU 

BUREAU  DE  LA  RADIOPROTECTION 

775  Brookfield  Road  « 

Ottawa   Ontario 

K1A    ICI 


TO/A:    MS  C.  BENNETT 

ADVISORY  COMMITTEE  ON 
ENVIRONMENTAL  STANDARDS 


FROM/DE:  DR.  PL  WAIGHT 


NO  OF  PAGES/NO.  DE  PAGES:    TWO 
MESSAGE: 

DEAR  MS  BENNETT, 

THANK  YOU  FOR  YOUR  FAX  WHICH  I  RECEIVED  THIS 
MORNING.  AS  FAR  AS  THE  PROPOSED  ONTARIO  STANDARD  IS  CONCERNED, 
7  kBq  REPRESENTS  AN  ANNUAL  DOSE  OF  0.0919  mSv,  BUT  I  WILL  ASSUME  A 
DOSE  OF  0.1  mSv  FOR  THE  PURPOSES  OF  THIS  REPLY;   LC 

THE    NOMINAL    PROBABILITY    COEFFICIENT    FOR    FATAL    CANCER 
INDUCTION  IS  GTVEN  BY  1CRP  IN  ITS  PUBLICATION  60  ON  PAGE  70  AS 
5  lO2  Sv1.  THUS  FOR  0.1  mSv  RECEIVED  ANNUALLY,  THE  TOTAL  LIFETIME 
RISK  WOULD  BE 

5  105X0.1  X70  =  3.4  10" 
TO  PUT  THIS  IN  PERSPECTIVE  IT  IS  PERHAPS  USEFUL  TO  COMPARE  IT  WITH 
THE  LIFETIME  RISK  OF  DYING  OF  CANCER  IN  THE  CANADIAN  POPULATION. 
THIS  IS  26.38%  FOR  MALES  AND  22.20%  FOR  FEMALES  (CANADIAN  CANCER 
STATISTICS  1992  PAGE  27).  ASSUMING  THAT  THERE  ARE  EQUAL  NUMBERS 
OF  MALES  AND  FEMALES  IN  CANADA,  THEN  THE  AVERAGE  RISK  WOULD  BE 
24.29%  OR  ABOUT  ONE  IN  FOUR.  THE  DOSE  OF  7  mSv  WOULD  ADD  A  RISK  OF 
ABOUT  ONE  IN  TWO  THOUSAND  NINE  HUNDRED  TO  THIS  RISK  OF  ONE  IN 
FOUR.  THIS  IS  AN  ADDITIONAL  RISK  OF  0.034%  TO  THE  EXISTING  24.29%. 
OTHER  COMPARISONS  CAN  BE  MADE: 

THE  AVERAGE  EXPOSURE  FROM  BACKGROU  N D  IS  ABOUT  2 . 8  mSv  y* ,  OR 
196^  mSv  OVER  70  YEARS,  COMPARED  WITH  THE  DOSE  FROM  THIS 
HYPOTHETICAL  SOURCE  OF  7  mSv. 

THE  O.lmSvlS  ALSO  WELL  WITHIN  THE  ANNUAL  FLUCTUATIONS  IN  THE 

85 


DOSE  FROM  BACKGROUND. 

THE  OTHER  POINT  THAT  IS  PROBABLY  WORTH  MAKING  IS  THAT 
BECAUSE  A  LIMIT  IS  SET,  IT  DOES  NOT  MEAN  THAT  THIS  LEVEL  WILL 
AUTOMATICALLY  BE  REACHED.  THE  CURRENT  LEVELS  OF  TRITIUM  IN 
DRINKING-WATER  RANGE  FROM  NON-DETECTABLE  TO  A  MAXIMUM  OF  50 
Bq/I  CLOSE  TO  A  NUCLEAR  POWER  STATION.  THE  INTRODUCTION  OF  A  7 
kBq  LIMIT  WILL  HAVE  ABSOLUTELY  NO  IMPACT  ON  THIS  LEVEL. 

I  AM  A  LITTLE  CONCERNED  THAT  TRITIUM  IN  DRINKING-WATER  IS 
BEING  CONSIDERED  IN  ISOLATION  FROM  OTHER  RADION  UCL1DES.  THE  WHO 
GUIDELINES  ARE  FOR  ALL  RADIONUCLIDES,  NATURALLY  OCCURJNG  OR 
MAN-MADE,  NOT  TO  EXCEED  THE  COMMITTED  EFFECTIVE  DOSE  OF  0.1  mSv 
FROM  ONE  YEAR'S  INTAKE. 

I  HOPE  YOU  FIND  THESE  COMMENTS  USEFUL. 


SIGNED: 


DATE:  14  MARCH  1994 


86 


Appendix  5:    U.S.  EPA's  Science  Advisory  Board  paper  entitled  Harmonizing 
Chemical  and  Radiation  Risk  Reduction  Strategies-A  Science  Advisory  Board  Commentary 

HARMONIZING3  CHEMICAL  AND  RADIATION  RISK-REDUCTION  ' 
STRATEGIES-A  SCIENCE  ADVISORY  BOARD  COMMENTARY 

Introduction 

Risk  assessment  and  risk-reduction  strategies  for  radiation  have  developed 
•within  a  markedly  different  paradigm  than  has  been  the  case  for  chemicals.  Radi- 
ation risk  assessment  has  been  based  largely  on  observations  in  humans  exposed  to 
relatively  well-known  doses  of  radiation,  while  chemical  risk  assessments  are  much 
more  often  based  on  projections  from  experiments  with  laboratory  animals  or  on 
human  epidemiology  with  relatively  uncertain  determinations  of  exposure.   Perhaps 
more  importantly,  radiation  risk-reduction  strategies  have  developed  almost  from 
the  start  under  the  assumption  that  it  would  be  necessary  to  balance  these  risks 
against  the  benefits  of  radiation  or  radiation-producing  technologies,  all  within  an 
environment  that  included  unavoidable  natural  sources  of  background  radiation.  By 
contrast,  chemical  risk-reduction  strategies  evolveded  from  an  initial  assumption, 
developed  early  in  this  century  for  food  additives,  that  public  health  could  be 
completely  protected.  Only  in  the  1960s  did  a  balancing  approach  become  well    . 
established  for  chemicals,  and  (in  retrospect)  even  then  it  was  aimed  at  reducing    . . 
risk  to  levels  that  would  be  considered  low  by  almost  any  criterion,  thereby  favoring 
protection  of  health  more  than  did  the  radiation  paradigm.  Furthermore,  for  many 
chemic?ls,  significant  natural  sources  were  either  absent  or  given  relatively  little 
consideration. 

The  discordance  or  lack  of  harmony  between  these  different  paradigms  was 
not  particularly  evident  until  the  Environmental  Protection  Agency  (EPA)  started  to 
deal  with  radiation  issues  in  the  context  of  decisions  that  also  needed  to  be  made  '^ 
about  chemicals,  for  example  with  respect  to  radionuclides  as  hazardous  air  pollute 
ants  under  the  Clean  Air  Act,  or  at  hazardous  waste  sites,  or  in  drinking  water' 
supplies  where  chemicals  are  also  present.  The  application  of  standard  chemical 
risk-reduction  criteria  to  radionuclides  in  these  situations  leads  to  limitations  on 
excess  radiation  dose  that  are  small  in  comparison  to  natural  background  radiation. 
Knowing  the  history  of  the  radiation  paradigm,  it  should  come  as  no  surprise  that 
some  radiation  scientists  see  such  limitations  on  radiation  exposures  as  unworkable 
or  even  misguided.  Some  chemical  risk  assessors  who  observe  radiation  protection 


Aj  applied  to  environmental  management,  'harmonizing'  i*  *  word  used  extensively  in  Europe  but  not  as  much  in  the 
United  States.   Harmonization  does  not  require  that  all  environmental  policies  be  identical  or  even  wholly  oontittent;  policiea 
«re  in  harmony  when  they  are  »e<n  aa  in  nine  with  en  overall  «trategy  and  not  discordant. 


87 


guidelines  corresponding  to  risks  greater  than  one  in  a  thousand  are  similarly 
puzzled:    how  can  such  high  absolute  risks  be  tolerated? 

Given  this  situation,  some  resolution  of  the  discordance  between  the  two 
paradigms  is  needed.  The  resolution  could  simply  be  to  assert  that  radiation  and 
chemicals  are  fundamentally  different  and  should  be  assessed  and  managed  differ- 
ently, or  some  synthesis  could  be  reached  that  takes  into  account  both  background 
issues  and  absolute  risk  levels.  As  an  example  of  the  latter  approach,  Kocher  and 
Hoffman  (1991)  have  recently  proposed  a  specific  risk  management  strategy  that 
may  be  applied  to  both  radiation  and  chemicals.   The  following  sections  describe  the 
radiation  and  chemical  paradigms  in  more  detail  and  suggest  some  possible  ap- 
proaches to  resolve  the  discordance  between  them. 

The  Radiation  Paradigm 

Current  risk  assessment  approaches  for  radiation,  whether  from  radionuclides 
or  from  other  sources,  developed  out  of  the  atomic  energy  program.   It  both  served 
as  a  framework  for  radiation  protection  for  atomic  workers  (and  later  for  the  gener- 
al public)  and,  under  the  rubric  of  "damage  assessment,"  was  used  to  predict  fatal- 
ities and  residual  health  impacts  from  the  radioactive  fallout  from  nuclear  weapons. 
In  assessing  risk,  health  physicists,  radiobiologists,  and  radiation  epidemi-ologists 
have  been  able  to  make  risk  estimates  of  relatively  high  precision  from  human  data. 
While  cancer  risk  estimates  for  radiation  entail  substantial  uncertainties,  especially 
at  low  doses  and  dose  rates,  they  are  seen  as  being  sufficient  to  justify  making  a  best 
estimate  of  risk  within  a  statistical  uncertainty  factor  of  about  2  for  all  cancers  com- 
bined for  whole-body  external  radiation  if  the  dose  is  known  accurately  (NCRP, 
1989).    These  best  estimates  of  risk  are  used  directly  without  further  safety  factors, 
of  any  kind.  Because  best  estimates  are  used  and  the  degree  of  uncertainty  is  only 
moderate,  risk  assessment  results  for  radiation  can  be  compared  with  risk  criteria 
for  control  decisions  with  some  confidence. 

Radiation  risk  assessment  was  heavily  influenced  by  the  thinking  of  physi- 
cists; in  fact,  "health  physicists"  are  more  likely  to  be  involved  in  the  practice  of 
radiation  protection  than  are  the  "radiobiologists"  who  study  the  fundamental  bio- 
logical aspects  of  radiation.   Typically,  the  description  of  radiation  risks  emulated 
the  mathematical  treatments  of  physical  systems,  often  using  phénoménologie 


Radiation  scientists  generally  aclcnowledge  that  no  ûnn  conclusions  «doth  risk  can  be  Tr.ade  for  total  dc*es  below  about 
10  rem.   If  the  liinr  dose-response  hypothesis  is  accepted  for  low-dose  extrapolation,  however,  the  risl  estimates  are 
relatively  precise.   In  this  report  the  units  of  rad  and  rem  have  b«n  used  rather  than  the  corresponding  ST  units  of  Gy  "■■^  Se. 
Tor  conversion  to  the  latter  units  all  numerical  values  are  divided  by  one  hundred. 


models  with  consideration  of  biological  theory  only  as  a  secondary  factor.    The  fit  of 
curves  to  cancer  data  from  radiobiological  experiments  were  interpreted  as  reflecting 
linear,  simple  quadratic,  or  linear-quadratic  dose-response  relationships,  and  the  un- 
derlying mechanisms  were  described  by  "target  theory"  as  "one-hit"  or  "two-hit"  and 
so  on.   Later,  it  was  postulated  that  radiation  created  breaks  in  DNA  which,  if  not 
repaired,  .could  result  in  somatic  mutations  and  eventually  in  cancer.  While  it  is 
now  believed  that  additional  mechanisms  —  e.g.,  radiation  effeds  on  oncogenes  — 
may  play  a  role,  the  mutation  hypothesis  for  radiation  carcinogenesis  still  heavily 
influences  radiation  risk  assessment  and  management  (NCRP,  1989). 

The  analysis  of  epidemiologic  information  followed  similar  models,  whether 
the  data  were  from  acute  doses  of  whole-body  gamma  irradiation  (Hiroshima  and 
Nagasaki),  fractionated  X  irradiation  (tuberculosis  patients,  for  example),  or 
protracted  irradiation  from  internally  deposited  radionuclides  (the  radium  dial 
painters  and  the  uranium  miriers).  Issues  arose  about  the  existence  of  thresholds 
for  radiation  carcinogenesis  (e.g.,  in  the  dial  painters)  or  at  least  "practical  thresh- 
olds" (e.g.,  the  idea  that  cancer  latency  was  inversely  related  to  dose  such  that 
manifestation  of  risks  at  low  doses  could  be  delayed  so  long  that  no  cancers  would 
occur  during  a  normal  lifetime). 

Underlying  all  this  development  was  the  knowledge  that  background  expo- 
sures to  radiation  in  the  range  of  about  70  to  250  millirem  per  year  (mrem/yr)  and 
averaging  perhaps  100  mrem/year  dose  equivalent  (NCRP,  1987)  were  inescapable. 
At  least  initially,  these  background  exposures  were  generally  assumed  not  to  confer 
significant  risks.   Thus,  as  recommended  radiation  standards  became  more  strin- 
gent with  the  discovery  of  adverse  effects  at  ever  lower  levels  of  protracted  exposure, 
the  radiation  scientists  kept  in  mind  the  difficulty  of  separating  excess  exposures 
from  natural  exposures  when  the  former  did  not  substantially  exceed  the  latter.  ■  ' 
Consequently,  cancer  risk-reduction  strategies  for  excess  radiation  exposures  have  '■■, 
very  probably  included  comparison  to  background  radiation  in  addition  to  the 
comparison  of  risks  and  benefits  resulting  from  radiation-producing  technologies, 
even  though  the  background  exposure  issue  has  usually  not  been  explicitly  presented 
in  such  decisions. 

When  in  the  early  days  the  critical  endpoints  for  radiation  protection  were 
effects  seen  only  at  what  are  now  considered  to  be  high  (e.g.,  erythema)  doses,  the 
allowable  excess  doses  were  easily  separable  from  normal  variability  in  background 
radiation.  The  standards  have  been  tightened  as  the  assumption  of  ho  threshold  for 
radiation  carcinogenesis  and  the  possibility  of  a  linear  dose-responsé  relationship  ' 
have  taken  hold  among  most  radiation  risk  assessors.  These  assumptions  have  been 


89 


employed  in  the  development  of  radiation  protection  policy.    Scientists  have  also 
learned,  however,  that  many  people  are  experiencing  exposures  to  the  lungs  from 
radon  and  its  progeny  that  confer  risks  several  times  that  from  the  100  mrem/year 
that  arises  from  cosmic  radiation,  terrestrial  gamma  radiation,  and  internal  potassi- 
uro-40  radiation,  averaging  perhaps  200  mrem/yr  (NCRP,  1987).  And,  a;  least  for  a 
time,  medical  diagnostic  and  therapeutic  radiation  increased  the  average  radiation 
dose  about  100  mrem/year  on  the  average. 

The  Internationa]  Commission  on  Radiological  Protection  (ICRP)  currently 
recommends  limiting  excess  environmental  radiation  exposures  to  a  total  of  100 
mrem/yr  for  the  general  population  flCRP,  1991).   In  addition,  the  ICRP  requires 
that  there  be  a  net  positive  benefit  and  that  the  ALARA  principle  be  adhered  to  that 
is,  that  exposures  should  be  kept  As  Low  As  Reasonably  Achievable  when  economic 
and  social  factors  have  been  taken  into  account.   The  ALARA  concept  appears  to  be 
the  radiation  protection  community's  equivalent  of  feasible  technology-based 
standards  for  chemicals. 

The  potential  cancer  burden  from  100  mrem/yr  exposure  is  not  always  made 
explicit  in  radiation  protection  guidance.  If  continued  over  a  lifetime,  however,  100 
mrem/yr  is  calculated  with  EPA's  current  risk  coefficient  for  radiation  carcinogene- 
sis to  cause  cancer  risks  of  almost  3  in  a  thousand  (3  x  10  )  (NAS/NRC,  1990). 
Some  analyses  would  predict  risks  up  to  three  times  higher,  i.e.,  close  to  one  in  one 
hundred. 

The  Chemical  Paradigm 

For  chemicals,  the  paradigm  is  different!- 1  Most  cancer  risk  assessments  are 
based  on  the  results  of  bioassays  in  animals  closed  rwith  chemicals  at  levels  thou- 
sands of  times  those  expected  in  the  environment,  not  from  human  data  of  high 
reliability.  To  deal  with  the  uncertainty,  EPA  in  particular  has  adopted  the  use  of 
the  upper  confidence  limit  on  the  slope  of  the  linearized  multistage  model  to  project 
risks  at  low  doses  and  has  used  a  conservative  procedure  -  the  surface  area  scaling 
rule  —  to  project  from  animal  bioassays  to  assumed  human  responses.   Both  of  these 
procedures  are  widely  believed  to  produce  risk  estimates  that  are  more  likely  to 
overestimate  than  underestimate  human  risk  (EPA  1986;  1989).  Thus  risk  esti- 
mates for  chemicals  are  biased  high  (even  though  such  may  not  be  the  case  with 
every  chemical).  This  conservative  method  of  dealing  with  uncertainty  ensures  that 
in  the  vast  majority  of  cases,  the  actual  risk  level  achieved  will  be  lower  than  the 
risk  criterion  used  in  a  control  decision. 


90 


Furthermore,  the  prototype  chemical  carcinogens  were  synthetic  substances 
with  no  or  limited  natural  sources.   In  calculating  excess  risk  from  human  sources  of 
a  chemical,  background  levels,  if  any,  are  therefore  frequently  seen  as  irrelevant, 
even  though  in  actuality  background  levels  from  either  natural  sources  or  anthropo- 
genic sources  other  than  the  one  being  considered  often  exist. 

Risk  assessment  for  chemicals  developed  from  the  ideas  of  medical  epidemi- 
ologists, biostatisticians,  experimental  biologists,  and  -  perhaps  most  importantly  - 
public  health  regulators.  Again  the  idea  was  to  protect  people  from  the  adverse 
effects  of  chemicals  on  health,  most  particularly  potential  carcinogenicity.  Here  the 
tradition  was  chemical  safety,  deriving  from  the  early  food  and  drug  protection  ideas 
to  keep  chemical  exposures  low  enough  to  protect  health  with  a  substantial  margin 
of  safety.  This  was  typically  accomplished  by  finding  some  "no-effect  level"  and  then 
dividing  by  "safety  factors"  with  the  goal  of  achieving  nearly  absolute  safety.  This 
approach  is  still,  used  for  non-carcinogenic  chemicals. 

The  idea  that  some  chemicals  might  be  a  little  dangerous  at  any  level  of 
exposure  (the  no-threshold  idea,  applied  especially  to  what  were  then  called  "radio- 
mimetic  chemicals")  came  as  quite  a  shock  to  the  regulators.  Congress  responded  in 
1958  by  attaching  the  "Delaney  Clause"  to  the  amendments  for  the  Food,  Drug,  and  ' 
Cosmetics  Act,  which  prohibited  the  addition  to  the  human  food  supply  of  any 
chemical  that  can  cause  cancer  in  humans  or  animals.  The  idea  remained  to  provide 
absolute  protection  against  cancer  risk. 

From  the  start,  however,  FDA  scientists  and  others  realized  that  assuring 
complete  absence  of  carcinogens  in  the  food  supply  was  impossible,  particularly  in 
view  of  the  rapidly  advancing  ability  of  the  analytic  chemists  to  detect  ever  lower 
levels  of  chemicals  in  food,  and  the  abundance  of  naturally  occurring  carcinogens.  . 
Almost  from  the  outset  of  the  Delaney  era,  therefore,  the  FDÂ  was  looking  for  the  '~ 
practical  equivalent  to  absolute  safety  in  a  world  where  thresholds  for  carcinogenesis 
could  not  be  assured.  FDA  and  NIH  scientists  soon  proposed  that  if  risks  calculated 
under  the  no-threshold  assumption  were  below  some  small  value,  the  carcinogen  was 
effectively  not  present  in  the  food  and  the  Delaney  Clause  would  be  satisfied.  The 
first  proposal  for  a  "virtually  safe  dose"  was  to  limit  cancer  risk  to  one  in  100  million 
(10**)  over  a  lifetime  of  exposure  (Rodricks  et  alp  1987).  The  idea  was  clearly  tied  to 
the  assumption  that  all  the  people  in  the  United  States  could  be  exposed  at  or  near 
the  virtually  safe  dose;  at  the  then-current  population  of  about  150  million,  only  one 
or  two  people  currently  alive  could  be  affected  even  if  all  the  conservative  assump- 
tions about  exposure  and  potency  proved  to  be  true. 


91 


Shortly  thereafter,  it  was  realized  that  the  10     criterion  itself  put  an  almost 
impossible  burden  on  the  regulator  for  assuring  the  safety  of  food  additives  with 
considerable  benefits.  Almost  as  a  reflex,  the  idea  arose  that  one  in  a  million  (10  ) 
was  a  lifetime  risk  that  most  people  would  find  negligible.  At  that  level,  everyone  in 
the  nation  could  be  exposed  and  only  about  3  excess  cancer  cases  per  year  would  be 
incurred,  again  even  if  the  risk  estimates  were  accurate  and  not  conservative.   Given 
that  everyone  would  not  be  so  exposed  if  one  calculated  the  risk  for  a  reasonably 
highly  exposed  person,  the  resulting  cancer  toll  would  clearly  be  invisible  and,  for 
most  people,  the  risk  insignificant. 

Although  quasi-scientific  arguments  have  been  offered  to  justify  the  one-in-a- 
million  criterion  for  acceptable  risk,  we  must  not  forget  that  it  originated  as  a 
number  of  convenience.   Nevertheless,  it  became  institutionalized  over  the  next 
several  years  and,  when  cancer  risks  from  environmental  exposures  became  recog- 
nized in  the  late  '60s  and  early  '70s,  the  concept  of  negligible  risk  at  10    was 

3  ^ 

applied  there.    Early  on,  the  types  of  risks  of  most  concern  were  widespread  ones 
such  as  exposures  to  PCBs  or  pesticide  residues  in  the  environment.   Later,  the 
same  risk  criteria  began  to  be  applied  to  much  less  widespread  risks  such  as  around 
industrial  facilities  or  hazardous  waste  disposal  areas. 

Eventually,  it  became  evident  that  10    was  a  very  stringent  criterion  when 
relatively  few  people  were  exposed.    Studies  of  EPA  decision-making  show  that  EPA 
often  has  chosen  not  to  require  reductions  in  exposure  when  the  calculated  risks 
were  as  high  as  10    or  even  10    when  the  population  exposed  was  small  (Travis  et 
al.,  19S7;  Rodricks  et  al.,  1987)." 

Moreover,  some  of  the  statutes  that  govern  chemical  regulation  by  EPA  and 
other  agencies  allow  or  even  require  a  balancing  of  the  risks  against  the  benefits  of 
the  technologies  involved  and  the  cost  of  control  strategies  in  determining  what  risk 
is  acceptable  in  a  specific  situation.    Others  simply  demand  action  whenever  risks 
are  determined  to  be  "substantial"  or  "significant,"  and  many  judicial  battles  have 
been  fought  over  the  meaning  of  these  directives.   For  example,  in  the  Vinyl 
Chloride  case  litigated  under  the  Clean  Air  Act,  the  court  ruled  that  chemical  safety 
did  not  imply  a  complete  and  unambiguous  freedom  from  risk,  but  also  that  the 


This  level  cf  risk  hmititicn  was  cot,  and  «till  is  Dot.  required  is  the  occupational  health  arena  where,  both  by  rireue  of 
arguably  ■voluntary  risk  and  by  precedent  fron  non-cancer  risks,  a  lifetime  risk  criterion  of  about  one  in  a  thousand  if 
considered  reasonable  for  occupational  exposure  to  carcinogens   (See  Rodricks  et  al,  1967,  pp.  31<).  Xven  in  the  occupational 
arena,  however,  radiatic::  eposure  limits  are  less  restrictive  in  risk  terms  than  are  chemical  exposure  limits.    Currently 
allowable  radiation  doses,  if  actually  incurred,  would  lead  to  a  lifetime  risk  cf  well  over  one  in  a  hundred,  perhaps  reaching  cne 
in  ten   (See  NaS/NHC.  1990.  pp.  172). 


92 


primary  safety  decision  had  to  be  made  without  considering  benefits  and  control 
costs  (Whipple,  1989).   Later,  risk/benefit  balancing  could  be  applied  in  determining 
an  adequate  margin  of  safety.   Such  risk-benefit  balancing  is  conducted  in  the  same 
spirit  as  the  optimization  principle  in  the  radiation  community,  but  at  a  different 
balance  point,  with  radiation  protection  requiring  lower  expenditures  per.  cancer 
avoided. 

Recently,  Don  R.  Clay,  EPA's  Assistant  Administrator  for  Solid  Waste  and 
Emergency  Response  (which  includes  the  Superfund  program)  has  indicated  that 
remediation  at  hazardous  waste  sites  need  not  be  undertaken  when  cancer  risks  for 
lifetime  exposures  are  calculated  to  be  below  10    (Glay,  1991).  Cancer  risk  levels  at 
or  above  10    are  also  accepted  in  setting  Maximum  Contaminant  Levels  (MCLs)  for 
carcinogens  in  drinking  water  (e.g.,  for  chloroform  from  water  disinfection)  when 
limiting  them  further  is  not  technically  or  economically  feasible.  Even  so,  many 
EPA  programs  still  apply  a  risk  criterion  in  the  10    to  10    range  to  a  (sometimes 
only  hypothetical)  "maximally  exposed  individual"  or  "reasonable  maximum  expo- 
sure." This  "individual  risk"  focus  does  not  place  as  much  weight  on  the  overall 
protection  of  public  health  (individual  risk  times  number  of  people  exposed  at  that 
risk  level)  as  does  a  "population  risk"  focus.  Whether  the  Agency's  judgment  is 
focused  on  individual  risk  or  on  population  risk  for  a  specific  situation  depends  on 
the  provisions  of  the  enabling  legislation  and  the  traditions  of  the  EPA  office  imple- 
menting it.  Risk-based  legislation  is  more  likely  to  result  in  an  individual  risk  focus, 
whereas  technology-based  standards  to  some  extent  skirt  the  individual  risk  issue 
and  implicitly  favor  a  population  risk  approach. 

Some  chemical  regulators  and  environmentalists  are  convinced  that  risk 
levels  above  one  in  a  million  are  not  acceptable  for  any  person,  invoking  arguments 
regarding  equity:  why  should  any  person  bear  à  cancer  risk  for  the  benefit  Of  other- 
people?  Why  should  all  people  not  he  afforded  -equal-  protection?  •  Why  should 
carcinogens  be  allowed  in  i.ie  environment  at  all?- And  everyone  would  agree  that  - 
all  opportunities  to  reduce  risk  should  be  seized  as  long  as  the  costs  —  economic, 
social,  or  other  —  are  not  too  high. 

Progress  toward  such  goals  is  much  easier  to  measure  when  there  is  no 
natural  background  exposure.  Synthetic  organic  chemicals  often  would  not  be 
observed  in  the  environment  at  all  if  not  for  human  activities;  even  when  natural 


93 


sources  can  be  identified,  the  risk  levels  for  the  natural  levels  of  exposure  are  often 
not  high  when  calculated  with  the  linearized  multistage  model  or  an  equivalent. 

Notwithstanding  these  similarities  to  the  radiation  paradigm,  the  chemical 
carcinogen  paradigm  tends  to  view  any  risk  levels  above  10  ,  even  to  a  very  few 
individuals,  as  potentially  excessive  and  therefore  requiring  action  to  reduce 
exposure  and  risk. 

Discordance  between  the  Paradigms 

Although  similarities  and  differences  in  risk  assessment  techniques  for 
chemicals  and  radiation  have  been  discussed,  (NCRP,  1989)  and  although  the 
difference  in  the  risk-reduction  strategies  between  these  two  paradigms  has  been 
recognized  by  some  scientists  and  regulators  for  several  years,  the  provinces  of  the 
health  physicists  and  the  chemical  risk  managers  stayed  relatively  distinct  until 
recently.'  As  the  EPA  gradually  took  on  greater  and  greater  responsibility  fcrr 
regulating  radiation  sources  as  well  as  chemical  ones,  the  discordance  became  more 
visible. 

The  difficulty  became  evident  in  several  EPA  program  areas.  When  EPA  had  •■ 
to  promulgate  National  Emissions  Standards  for  Hazardous  Air  Pollutants 
(NESHAPs)  for  radionuclides,  it  needed  to  harmonize  the  residual  risk  levels  with 
those  allowable  for  other  carcinogenic  air  pollutants  such  as  benzene.   In  the  course 
of  analyzing  sources  of  airborne  radionuclides,  more  stringent  controls  were  pro- 
posed for  them  than  would  have  been  thought  necessary  to  keep  radiation  doses  to 
100  mrem/yr  or  somewhat  less.   Furthermore,  EPA  had  to  wrestle  with  the  fact  that 
.  prior  emissions  from  (or  other  practices  of)  these  facilities  may  have  left  residual 
radioactivity  "in  communities  across  the  country  producing  radiation  doses  with 
calculated  risks  greater  than  one  in  ten  thousand.-  The  Radiation  Advisory  Commit- 
tee (SAB,  1992a)  recently  commented  on  the  Idaho  Radionuclides  Study,  in  which 
some  people  may  have  received  excess  gamma  radiation  of  the  same  magnitude  as 
typical  background  radiation  levels,  i.e.,  about  100  mrenvyr,  from  uranium-series 
radionuclides  in  elemental  phosphorus  slags  distributed  in  their  community. 
Elsewhere,  EPA  is  dealing  with  radon  emanations  from  phosphogypsum  stacks  or 
with  radionuclides  from  processing  of  rare  earths  for  radium,  thorium,  or  non- 
radioactive materials. 


In  a  few  irtuaticns  -  arsenic  in  drinking  water  cornea  to  mind  —  the  calculated  risk  levels  of  natural  apocure  are  high. 
In  «ruch  cases,  the  idea  of  comparison  to  background  of  chemical  carcinogens  if  mere  likely  to  be  invoked,  often  by  stipulating 
that  there  is  no  excess  exposure  if  measured  concentrations  are  not  beyond  the  confidence  limits  en  the  distribution  cf 
background  ccncentrivicns- 


94 


A  second  area  of  discordance  grew  out  of  the  recognition  of  waste  problems 
involving  radioactive  materials  that  were  under  the  purview  of  EPA  or  state 
environmental  agencies  rather  than  the  Nuclear  Regulatory  Commission  or  the 
nuclear/radiation  safety  agencies  in  agreement  states.    The  most  striking  of  these 
are  the  radioactive  or  mixed  waste  problems  at  sites  that  have  been  placed  on  the 
National  Priority  List  for  attention  by  the"  Superfund  Program.  Here  the  wastes  of 
most  concern  are  often  the  radionuclides  of  the  uranium  or  thorium  series  that  are 
also  found  in  nature,  and  which  have  for  the  most  part  been  "technologically 
enhanced"  by  human  activities,  rather  than  created  by  them. 

The  facilities  of  the  Department  of  Energy  that  are  part  of  the  nuclear 
weapons  complex  form  another  group  of  problem  sites  where  radionuclides  are  a 
significant  or  even  dominating  part  of  the  cancer  risk  equation.  Whether  these 
facilities  are  treated  as  Superfund  (CERCLA)  problems  or  current  waste  disposal 
sites  under  the  Resource  Conservation  and  Recovery  Act  (RCRA),  the  treatment  of 
radioactive  materials  is  seen  as  necessarily  being  subject  to  the  same  types  of  risk 
analyses  and  remedial  responses  that  EPA  has  used  for  chemicals.  The  document 
"Risk  Assessment  Guidelines  for  Superfund"  (RAGS),  for  example,  contains  a  section 
on  how  to  assess  the  cancer  risks  from  exposure  to  radionuclides,  but  does  not 
suggest  any  different  risk-reduction  strategies  than  for  carcinogenic  chemicals.  The 
implication  is  that  remediation  is  expected  if  the  lifetime  risks  from  radionuclides 
are  calculated  to  exceed  about  10    (or  lower  in  some  proposals  for  radiation  sites). 

The  differences  in  the  radiation  and  chemical  paradigms  have  also  become 
apparent  in  EPA's  actions  with  respect  to  radon  in  homes.  The  current  EPA 
guidance  Taction  level")  for  home  remediation  is  4  pCi/L  of  radon  in  air  in  the , 
lowest  lived-in  area,  which  by  current  EPA  risk  assessment  methods  translates  to  a 
lifetime  risk  of  over  1  in  100  or  10,000  in  a  million  (1x10  j  for  an  average  person 
(smokers  and  nonsmokers  combined)  (ERA,   1991a).  The  Agency. is  clearly, not    ;-.  -> 
implying  that  such  a  level  of  risk  is  acceptable  in  an  absolute  sense,- but  appears  to   .- 
be  applying  a  rule,  of  practicality  based  on  the  difficulty  of  reducing  exposure  levels 
much  below  4  pCi/L  within  a  reasonable  budget.   EPA  also  must  work  on  the  radon 
issue  without  a  clear  legislative  mandate  encouraging  the  Agency  to  regulate 
homeowners'  choices. 

EPA  has  reacted  differently  to  the  legislative  requirement  to  control  levels  of 
radon  in  drinking  water.  Using  an  approximation  of  the  chemical  paradigm,  the 
Office  of  Drinking  Water  has  proposed  that  public  water  utilities  must  treat  water 
that  contains  radon  above  300  pCi/L  (EPA  ,  1991b),  a  level  yielding  a  risk  in  the    • 
vicinity  of  one  in  ten  thousand  (1  x  10  ),  even  though  this  level  of  risk  is  two  orders 


95 


of  magnitude  lower  than  what  is  recommended  for  radon  in  air  and  the  cost  per 
calculated  life  saved  is  substantially  greater  than  for  remediation  of  radon  in 
household  air  (SAB,  1992a). 

It  can  be  argued  that  the  discordance  between  radiation  and  chemical  risk- 
reduction  strategies  is  simply  another  manifestation  of  necessary  differences  in' 
regulatory  choices  in  different  situations.   Indeed,  good  reasons  exist  to  make  all 
risk-reduction  decisions  within  a  framework  intended  to  reduce  overall  risk  levels 
without  excessive  attention  to  keeping  the  risks  from  any  one  situation  within 
inflexible  guidelines.   Clearly,  the  requirements  of  the  various  statutes  enabling 
EPA's  regulatory  activities  force  the  Agency  to  formulate  and  apply  some  discordant 
and  seemingly  inconsistent  policies.    Nevertheless,  the  Committee  believes  that  the 
differences  between  the  chemical  and  radiation  paradigms  are  more  troublesome 
than  the  variation  within  each  area  of  regulation. 

In  each  new  case  of  radiation  risk  management,  EPA  can  follow  the  chemical 
tradition  of  regulating  risks  to  the  vicinity  of  10    or  lower  or  the  radiation  tradition 
of  tolerating  (where  inexpensive  remedies  are  not  readily  available)  an  approximate 
doubling  of  the  risks  from  natural  background  radiation,  which  are  in  the  vicinity  of 
3  *  10    for  background  exclusive  of  radon  and  nearly  one  in  a  hundred  (10  j  when 
radon  is  included.  This  disparity  can  and  has  led  to  considerable  lack  of  under- 
standing and  conflicts  between  health  physicists  and  chemical  risk  managers.   Even 
the  existence  of  an  analogy  in  the  chemical  world  to  the  radionuclide  problem  —  the 
background  levels  of  carcinogenic  inorganic  substances  such  as  arsenic  and  the 
existence  of  substantial  quantities  of  natural  organic  carcinogens  in  foods  (Ames  and 
Gold.,  1990)-  has  not  brought  about  any  resolution  of  this  discordance. 

Need  for  Harmonization 

Clearly,  EPA  needs  to  adopt  policies  that  will  allow  its  staff,  the  regulated 
community,  scientific  consultants  to  both  parties,  and  the  general  public  all  to  know 
what  to  expect  in  EPA's  regulation  of  residual  radioactivity  and  other  radiation 
issues.   The  Radiation  Advisory  Committee  does  not  claim  any  special  insight  in  how 
the  resolution  should  be  accomplished,  but  does  emphasize  the  importance  of 
achieving  such  harmonization.   Interest  in  the  comparative  risks  of  radiation  and 
chemicals  has  a  substantial  history  (NCRP,  1989)  and  is  now  becoming  more 
widespread  (Kocher  and  Hoffman,    1991). 

One  approach  could  be  to  assert  that  radiation  and  chemical  regulations  are 
fundamentally  different,  perhaps  because  of  the  unavoidability  of  background 


96 


radiation.  The  guidance  of  the  ICRP  on  dose  limitation  (currently,  100  mrem/yr 
whenever  the  ALARA  principle  does  not  result  in  lower  levels)  could  become  the 
explicit  policy  of  the  Office  of  Radiation  Programs  (ORP),  and  other  branches  of 
EPA  could  explicitly  defer  to  ORP  on  radiation  and  radioactivity  issues. 

A  second  set  of  alternative  approaches  would  strive  for  clear  consistency 
between  the  radiation  and  chemical  risk-reduction  strategies.  .The  two  extreme 
cases  are: 

a.         Use  the  optimization  principle  along  with  background  risks  from 

radiation  as  guidance  for  how  much  excess  risk  can  be  tolerated  from 
any  source,  be  it  chemical  or  radiation.   Excess  risks  in  the  range  of 
10    or  a  bit  higher  would  be  used  as  a  criterion  for  remedial  actions  or 
regulations  where  remediation  is  expensive  and  not  easily  achieved. 
Use  the  ALARA  principle  whenever  it  applies,  that  is,  when  risks  can 
•   be  reduced  without  excessive  penalties  in  terms  of  social  or  economic 
costs.  Make  provisions  for  dealing  with  hazards  in  those  cases  where 
exposures  even  at  the  calculated  10    risk  level  are  not  detectable  or 
distinguishable  from  background  (i.e.,  ALARA  should  apply  whenever  ,- 
risk  reduction  can  be  reasonably  anticipated  even  though  it  cannot  be 
measured).        .     . 

b.         Regulate  radiation  risks  exactly  as  chemical  risks  are  now  regulated. 
Use  10    as  a  standard  criterion  for  remediation  or  regulation,  regard- 
less of  how  the  corresponding  standards  compare  with  background 
levels  of  exposure.  Use  the  absolute  value  of  risk  in  excess  of  back- 
ground risk  as  a  criterion,  not  the  fractional  increment  relative  to. 
background  risk.  Make  practical  exceptions  for  the  inability  to  detect 
some  of  the  regulated  exposures  at  thé  selected  level  of  risk,  just  as  is 
done  for  chemical  substances  when  the  detection  limit  exceeds  the    : 
target  for  regulation,  as  is  the  case  for  dioxin  in  water.   Take  costs  and 
benefits  into  account  where  the  applicable  legislation  provides  for  that  . 
possibility. 

The  Radiation  Advisory  Committee  recognizes  that  neither  of  these  latter 
options  may  be  practicable  given  the  history  of  how  the  two  paradigms  developed. 
Probably  more  likely  to  be  accepted  would  be  a  third  option  that  seeks  a  compromise 
risk-reduction  strategywith  an  intermediate  risk  acceptance  criterion  or  criteria. 


97 


As  a  third  option,  the  Agency  could  determine  that,  because  the  physical 
characteristics  of  the  two  types  of  agents  are  so  different  and  because  the  approach- 
es to  monitoring  and  regulating  them  have  developed  so  differently,  bringing  the  two 
fxeas  into  rigid  conformity  in  the  near  term  is  very  likely  not  possible,  however 
societally  or  ethically  desirable  as  a  long-term  goal   The  Radiation  Advisory 
Committee  strongly  suggests  in  this  case  that  the  two  approaches  be  harmonized— 
that  is,  fitted  into  a  common  policy  framework  aimed  at  aggregate  risk  reduction  but 
not  necessarily  achieving  such  reductions  in  identical  ways  or  with  identical  risk 
criteria  in  every  case  (see  Deisler,  1984,  for  an  example  of  harmonization  in  the 
chemical  safety  field).   The  harmonization  between  chemical  and  radiation  risks  of 
different  types  could  occur  by  clearly  and  explicitly  taking  into  account  the  differenc- 
es in  risk-reduction  criteria  or  strategies  between  hazards  that  have  natural  sources 
(rather  than,  or  in  addition  to,  anthropogenic  sources)  and  those  that  have  only 
anthropogenic  sources:   For  example,  risk  criteria  for  substances  with  no  natural 
sources  (including  radionuclides  such  as  plutonium  or  americium)  could  be  different 
from  those  used  for  substances  that  have  natural  sources  (including  carcinogenic 
inorganic  substances  and  organic  materials  with  significant  natural  sources). 

Whatever  the  nature  of  harmonization  between  the  radiation  and  chemical 
paradigms,  it  will  need  to  incorporate  as  well  the  differences  among  ambient 
environmental  and  indoor  and  occupational  exposures,  and  the  distributions  of  risks 
and  benefits  among  exposed  individuals  and  the  sources  of  the  exposure. 

Clearly,  the  choice  among  these  options  -  and  others  that  may  exist  —  is  a 
policy  choice  that  transcends  scientific  analysis.      The  leadership  of  the  Environ- 
mental Protection  Agency  has  the  authority  and  the  responsibility  to  make  the 
choice.  We  urge  the  choice  to  be  articulated  clearly  so  that  the  scientists  who  assess 
the  risks  of  radiation  and  chemicals  can  understand  the  basis  for  subsequent 
decisions  about  risk  reduction. 


98 


REFERENCES 

Ames,  B.N.,   and   L.S.   Gold,  1990.   Too   Many   Rodent   Carcinogens:   Mitogenesis 
Increases  Mutagenesis,  Science  249:970-971,   . 

Clay,  D.R,  1991.  Role  of  the  Baseline  Risk  Assessment  in  Superfund  Remedy  Selec- 
tion Decisions,- Environmental  Protection  Agency  Memorandum,  April  22,  1991,  p.  1 

Deisler,  P.F.  Jr.,  1984.  Reducing  the  Carcinogenic  Risks  in  Industry,  Marcel- 
Dekker,   pp.  135-158. 

EPA,  1986.  Environmental  Protection  Agency,  Guidelines  for  Carcinogen  Risk 
Assessment,  Fed.  Reg.  51:33992-34003,  September  24,  1986.. 

EPA,  1989.  Environmental  Protection  Agency,  Risk  Assessment  Guidance  for  . 
Superfund,  Vol.  1,  Human  Health  Evaluation  Manual  (Part  A),  EPA/540/1-89/002, 
pp.  8-6. 

EPA,  1991a.  Environmental  Protection  Agency,  Proposed  Revisions  in  EPA  Esti- 
mates of  Radon,  Risks  and  Associated  Uncertainties. 

EPA,  1991b.   Environmental  Protection  Agency,  National  Primary  Drinking  Water 
Regulations;  Radionuclides;  Proposed  Rule,  Fed.  Reg.    56:33050-33127,   July   18, 
1991,  pp.   33051. 

ICRP,  1991.  International  Commission  on  Radiological  Protection,  Radiation 
Protection:  1990  Recommendations  of  the  International  Commission  on  Radiological 
Protection,  ICRP  Publication  60,  Pergamon  Press.  ; 

Kocher,  DC,  and  F.O.  Hoffman,  1991.     Regulating  Environmental  Carcinogens: 
Where  Do  We  Draw  the  Line?,  Env.  Sci.  Technol.  25:1986-1989. 

NAS/NRC,  1990.  National  Research  Council,  Health  Effects  of  Exposure  to  Low 
Levels  of  Ionizing  Radiation  (BEIR  V).  Report  of  the  Committee  on  the  Biological 
Effects  of  Ionizing  Radiations,  National  Academy  Press,  pp.  172-173.    . 

NCRP,  1987.  National  Council  on  Radiation  Protection  and  Measurements,  Expo- 
sure of  the  Population  of  the  United  States  and  Canada  from  Natural  Background 
Radiation,  NCRP  Report  94. 


99 


NCRP,  1989.   National  Council  on  Radiation  Protection  and  Measurements,  Com- 
parative Carcinogenicity  of  Ionking  Radiation  and  Chemicals,  NCRP  Report  No.  96, 
pp.2. 

SAB,  1992a:  Science  Advisory  Board,  Radiation  Advisory  Committee,  Idaho  Radionu- 
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SAB,  1992b:  Science  Advisory  Board,  Radiation  Advisory  Committee,  Reducing 
Risks   from   Radon;  Drinking  Water  Criteria  Documents,  EPA-SAB-RAC-COM-92- 
003,  January  29,  1992. 

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Federal  Regulatory  Agencies,  Reg.  Toxicol.  Pharmacol.  7:307-320,  1987,  p.  308,  310- 
313 

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Whipple,  C,  1989.  Courts  Speak  on  Risk  issue,  Forum  Appi.  Research  Publ.  Policy, 
4:96-99. 


100 


Appendix  6:   The  Effect  of  Various  Issues  on  the  Recommended  ODWO 


Issue 

Effect  on 

Resulting 

ODWO  (Bq/L) 

(Uncertainty) 

ODWO 

Level  of 

(Reduction 

Risk 

Factor) 

(Excess 
Cancers 

per 
1,000,000 
Exposed) 

MOEE  proposed  ODWO 

- 

>340 

7,000 

Rationale  Document 

(MOEE*  s 

(Based  on  1  year  of  exposure) 

proposed  Interim 
ODWQ) 

Lifelong  Exposure 

70 

>5 

100 

(Based  on  a  70  year  lifespan) 

(ACES' s 

recommended 

Drinking  Water 

Objective) 

Risk  Reduction  from  5  excess  cancers 

5 

>  1 

20 

per  million  exposed  to 

(ACES' s 

1  excess  cancer  per  million  exposed. 

recommended  five 
year  target) 

RBE*  1  or  >1; 

1  -3 

(  1 

Natural 

Dose  Conversion  Factors; 

? 

Background 

Areas  of  Uncertainty; 

(Ultimate  goal) 

Organically  Bound  Tritium  (longer 

biological  half-life) 

*RBE  is  the  relative  biological  effectiveness  of  tritium  (also  see  Glossary). 


101 


Appendix  7:    1991  Tritium  Data  from  the  Nuclear  Surveillance  Program 
and  Analysis  of  Tritium  in  Drinking  Water 

Source:  Rationale  I  k>  umenl  foi  th    I  >eveIopmeni  ol  an  Interim  «  Ontario  I  >rinl  ing 

Watei  Objective  for  Tritium.    November,  1993.    Standards  Development 
Branch,  Ontario  Ministry  of  the  Environment  and  En  I  pp. 


AIT!  NDLX  I    .'  :  1991  TRITIUM  DATA  -  NUCLEAR  SURVEILl^AN'CE  PROGRAM 


PLANT 

Range  (Bq/I)  in  Treated  Water 

AJAX  WTP 

<  9-  50 

AMHERSTBURG  WTP 

<  8-  34 

BOWMANVTLLE  WTP 

<  9-27 

DEEP  RIVER 

<  8-  12 

HARROW-COLCHESTER 

<  8-  12 

KINCARDINE  PUC 

<  8-  25 

NEWCASTLE 

<  8-  24 

OSHAWA  WTP 

<  9-36 

PETAWAWA 

<  9  -  370 

PEMBROKE 

<  9  -  270 

PICKERING 

17  -  21 

TORONTO 

<  8  -  57 

WARKWORTII 

<  9 

WHEATLLY  WTP 

<  9  -  1 1 

WHITBY  UTP 

*. 

VERNEIîR  WTP 

<    10 

APPENDIX  D  :  ANALYSIS  OF  TRITIUM  IN  DRINKING  WATER 

The  analysis  of  tritium  in  drinking  water  is  conducted  by  the  Radiation  Protection 
Service  Laboratory  (RPSL)  of  the  Ontario  Ministry  of  Labour. 


The  procedure  used  for  the  determination  of  tritium  in  water  begins  with  the  distillation 
of  the  samples.   The  middle  fraction  of  the  distillate  is  combined  with  a  liquid 
scintillation  cocktail  and  counted  in  a  Liquid  Scintillation  Counter.    Normal  reported 
detection  limits  are  approximately  7  Bq  per  litre. 

Also  see:         Appendix  E.  1,  p.  25.  of  Rationale  Document  for  the  Development  of  an 
Interim  Ontario  Drinking  Water  Objective  for  Tritium. 

102 


Mark  Goldberg* 

Chair  of  ACES 

GlobalTox  International 

Consultants  Inc. 

&  University  of  Guelph 

Guelph 

Ian  Brindle 
Analytical  Chemistry 
Brock  University 
St.  Catharines 


Cindy  O'Brien* 
Occupational  Hygenist 
City  of  Toronto 
Toronto 

Kim  Perrotta 

Occupational  Health 

&  Safety 

Labour  Consultant 

Toronto 

Keith  Winterhalder 
Plant  and  Soil  Ecology 
Laurentian  University 
Sudbury 


ACES  Members 

Beth  Savan* 

Vice  Chair  of  ACES 

Environmental  Research  and 

Education 

University  of  Toronto 

Toronto 

Terry  Burrell 
Environmental  Economics 
and  Law 
Toronto 


Sally  Paterson* 

Environmental  Chemodynamics 
University  of  Toronto 
Toronto 

Catherina  Spoel 
Environmental  Law 
Miller  Thomson 
Toronto 


Robert  Boldt 
Occupational  Health  and 
Environment 
Samia 


Doug  Cook 

Occupational  Health  and 

Environment 

Taurscale  Consultants  Ltd. 

Bridgenorth 

David  Pengelly 

Air  Pollution  Epidemiology 

McMaster  University 

Hamilton 

Ralph  Stanley* 

Public  Health  Protection 

Peel  Regional  Health 

Department 

Brampton 


Denotes  Member  of  Tritium  Workgroup 


ACES  Staff 


Carol  Bennett 
Technical  Advisor 


Carole  Brown 
Receptionist 


Dianne  Corrigan 
Scientific  and  Technical 
Coordinator  (Acting) 


Kathy  Paidock 
Administrative  Assistant 


Advisory  Committee  on  Environmental  Standards 

Suite  401 

40  St.  Clair  Ave.  West 

Toronto,  Ontario 

M4V  1M2 

Phone:    (416)314-9265 

Fax:    (416)314-9270 


Ontario