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Full text of "A standard for tritium : a recommendation to the Minister of the Environment and Energy"

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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 Pa 8 e 

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 I 4 

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 CAN adian 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 10 10 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 ( 3 H). The resulting tritiated water is regularly discharged 
from these reactors. Radioactive tritium* ( 3 H) decays to non-radioactive helium ( 3 He) 
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 litres 1 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 exposed 2 . 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. 

2 Please 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 recommendations 1 . 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 facilities 1 . 

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/L 1 , 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 ...•■■- 



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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 
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 Bq/L... the objective that you 
recommend to the MOEE should be 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 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 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 lO 2 Sv 1 . THUS FOR 0.1 mSv RECEIVED ANNUALLY, THE TOTAL LIFETIME 
RISK WOULD BE 

5 10 5 X0.1 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 

HARMONIZING 3 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 che micals 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 al p 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- 
clide Study, EPA-SAB-RAC-LTR-92-004, January 21, 1992. 

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. 

Rodricks, J.V., S.M. Brett, and G.C. Wrenn, 1987. Significant Risk Decisions in 
Federal Regulatory Agencies, Reg. Toxicol. Pharmacol. 7:307-320, 1987, p. 308, 310- 
313 

Travis, C.O, et al., 1987. Cancer Risk Management, Env-Sci. Technol. 21:415420. 

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