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564                                               MEDICAL JURISPRUDENCE


Barium Chloride, BaCl2.—This forms colourless, rhombic crystals, having an acrid
taste, and soluble in water. It is chiefly used as a chemical reagent. It is highly poison-
ous, and has been taken in mistake for Carlsbad salt or Epsom or Glauber's salt. It is
a non-official preparation, the dose being J to 2 grains.

Barium Nitrate, Ba(NO3)2.—This crystallizes in large, colourless octahedra. It is
soluble in water. It is used in pyrotechny to make green fire.

Barium Carbonate, BaCO3.—This occurs as a mineral witherite. It is a fine, white
powder, slightly soluble in water, but soluble with effervescence in dilute acids, and
may be converted by the free hydrochloric acid of the stomach into barium chloride. It
is largely used as a poison for rats and mice.

Barium Sulphate, BaSO*.—This occurs native as heavy spar. It is a heavy, white,
tasteless, odourless powder. It is insoluble in water, and only very slightly soluble in
dilute acids. It is largely used as a white pigment, known as permanent white. It is
not poisonous and has recently come into very large use for the X-ray examination of
the oesophagus, stomach and intestines. The non-official dose of barium sulphate is 2 to 5

Barium Sulphide (Baryta Sulphurata, B.P.C.) BaS.—This occurs as a greyish-black
powder and dissolves readily in water giving off an offensive odour of hydrogen sulphide.
It is a deadly poison and is chiefly used as a depilatory.

Symptoms.—The symptoms appear within half-an-hour after swallowing the poison.
These are severe abdominal pain, nausea, salivation, vomiting, intense thirst, persistent
purging, dilatation of the pupils, dimness of vision, ringing in the ears, violent cramps in
the hands and feet, slow, forcible and intermittent heart beats with rise of blood pres-
sure, convulsions, paralysis, collapse or coma and death.

Fatal Dose.—The fatal dose of a soluble barium salt is variable. Sixty grains of
barium chloride and barium carbonate have each proved fatal. On the other hand,
recoveries have followed much larger doses of these salts.

Fatal Period.—Death may occur rapidly in one to two hours or may be delayed
for some days. A woman died in 19 hours after swallowing by mistake half of a solution
containing 30 grammes of barium chloride instead of sodium sulphate.74 A man who
was given a powder conatining barium carbonate and barium sulphide in soup by his
wife died on the third day.75

Treatment.—Give one-ounce doses of sodium or magnesium sulphate to form an
insoluble salt of barium sulphate, and then give emetics or wash out the stomach with
milk and water. Use morphine to relieve pain, and stimulants to combat collapse. Give
nitro-glycerin or amyl-nitrite to reduce the blood pressure.

Post-mortem Appearances.—Reddening, congestion and inflammation of the mucous
membrane of the stomach and duodenum; sometimes erosions of the mucous membrane.
The heart is large and flabby. The lungs and brain are congested.

Chemical Tests.-—1. Dilute sulphuric acid gives a white precipitate of barium sul-
phate, insoluble in hydrochloric and nitric acids.

2.    A solution of potassium chromate added to a neutral solution of a barium salt
produces a yellow precipitate of barium chromate, soluble in nitric acid and in hydro-
chloric, acid, but insoluble in acetic acid.

3.   A few drops of a 5 per cent solution of the sodium salt of chloronitrotoluene-
sulphonic acid added to a neutral or faintly acid solution of a barium salt produces a
crystalline precipitate even in a dilution of 1 in 2,000.   It gives no precipitate to calcium
or strontium salts.

4.   Feigl's Test.—If a drop of a neutral solution of a barium salt is placed on a piece
of filter paper_ which has been soaked in a freshly prepared solution of sodium rhodi-
zonate and dried, a reddish stain or precipitate is formed which, when moistened with
hydrochloric acid, changes to scarlet.

5.    Barium salts moistened with hydrochloric acid impart a greenish-yellow colour
to name.

Medico-Legal Points.—The soluble salts of barium are highly poisonous. They have
locally an irritant action and remotely have a depressant action on the heart.

Most of the cases of poisoning by barium salts are accidental, taken, in mistake for
Epsom or other purgative salts. A few are suicidal.

74.   E. Gilli, Archivio di Antropologie Criminate, etc., Turin, Jan.-June 1947   p   24:
Jour. Amer. Med. Assoc., Oct. 25, 1947, p. 540.

75.   Madras Chem. Examiner's Annual Rep., 1933, p   4