Text-book of forensic medicine and toxicology

by R. J. M. Buchanan

Cacodylic acid and the cacodylates are poisonous. The acid dissolves easily in water and alcohol, and it unites with many metals and organic substances to form salts. Although it is held by some to be non-poisonous, Murrell asserts that the administration of cacodylate of sodium produces symptoms “far more severe than those which follow the exhibition of arsenic in its ordinary forms” (B. M. J., 1900, vol. ii. p. 1823; 1901, vol. i. p. 120).

Professor Fraser of Edinburgh, on the other hand, from clinical observation and chemical tests, affirms that cacodylic acid and the cacodylates are extremely stable bodies, and the arsenic in them is with such great difficulty set free that it passes through the body in combination as an inert substance (B. M. J., 1902, vol. i. p. 713).

Arsenical Contamination of Food Stuffs

Arsenic is found associated with many other substances in nature, particularly copper and pyrites. Arsenic is commonly present in commercial sulphuric acid manufactured from pyrites containing the metal, and when such acid is used with common salt for the production of hydrochloric acid, the latter also becomes contaminated. It may be safely stated that commercial sulphuric acid, hydrochloric acid, copper and zinc, free from arsenic, do not exist in the market. Hence in the detection of arsenic by the toxicologist the absolute purity of these reagents, which he uses, must be established.

In the manufacture of glucose, arseniferous sulphuric acid has been the means of contaminating it. Ritter and Blyth pointed out the danger, by this means, of conveying arsenic into beer, confectionery, syrup, and other food stuffs. Glucose made with such acid, and used in the manufacture of beer, was the cause, in the year 1900, of a widespread and serious epidemic of arsenical poisoning in Manchester and Liverpool, in which several thousand persons suffered. Arsenic may also contaminate grain during malting by the use of anthracite coal or sulphur bar in the kilns.

Recapitulation of the Leading Facts
with regard to Poisoning
with Arsenic

ACUTE POISONING.—SYMPTOMS, ETC.
Action on alimentary canal.	Intense irritation of the stomach, upper
	part of small intestine, and lower part
	of the large. The inflamed condition of
	the stomach occurs even if arsenic be
	absorbed by the skin. Not present in
	all cases.
Circulation	The heart weakened, with a consequent
	reduction in force and frequency of
	pulse.
The brain and nervous system.	In some cases the action upon the brain
	is that of a narcotic, and the
	paralysis sometimes seen appears to
	be due to a direct action of the drug
	on the cord.
The urinary organs	Arrest of the action of the kidneys is
	not uncommon. Stranguary.
Fatal dose	Two grains.
Average period of the	From half an hour to an hour after the
commencement of the	poison is taken.
symptoms.
Average period before death.	Ten to twenty-four hours.
CHRONIC POISONING.—SYMPTOMS, ETC.
The eyes, nose, and mouth	Irritation and redness of the eyes and
	nostrils. Dryness of the mouth and
	throat.
The stomach and bowels	Loss of appetite, colicky pains, cramps,
	irritability of bowels, mucous
	discharges.
Nervous system	Depression and irritability of spirits,
	sleeplessness, giddiness, convulsions,
	vertigo, paralysis, etc.
Cutaneous surface	Brown pigment deposit in the skin of
	the face. “Eczema arsenicale,” etc.
Means of diagnosis in	Examine the urine unostentatiously.
suspected cases.	Remove patient from present abode.
	Examine wall-paper, etc., for arsenic.
The probable post-mortem	Signs of irritation, slight or absent,
if death is due to this poison.	in stomach and bowels.
Organs most important to	Liver, stomach, kidney.
secure for analysis.
Circumstances under which	Green wall-papers, coloured toys and
it may occur independently	sweets, green tarlatan dresses, etc.
of criminal administration.

ANTIMONY

Antimony, the Stibium of the ancients, is obtained from the native sulphide. Metallic antimony is of a bluish-white colour, crystalline and brittle. It melts at about 840° F., and is slowly volatilised at a white heat.

Two compounds of antimony—tartar emetic and chloride of antimony—are alone of any toxicological interest.