ANILINE
Aniline is a colourless oily liquid gradually changing to brown on exposure to air. The various aniline dyes are obtained by oxidation of aniline. Aniline is produced by reduction of nitrobenzene. It is slightly soluble in water, freely so in alcohol or ether. It can be absorbed through the unbroken skin as well as by the lungs and mucous membranes. It is used in the manufacture of marking inks. It has very toxic properties.
Symptoms.—The symptoms come on rapidly—nausea and vomiting, with giddiness and drowsiness; the lips, face, ears, fingers, toes, conjunctivæ, and mucous membranes become cyanotic. The respirations are slow and laboured. The pulse may be full and slow, or small and irregular. The body surface is cold, the pupils react sluggishly to light. The blood is chocolate-coloured, and is said to give the spectrum of methæmoglobin. The blue colour is held to be due to pigment changes, and not to true cyanosis. Convulsions and coma may come on in fatal cases.
Buchanan met with a case of aniline poisoning in a man who by mistake swallowed about half an ounce of marking ink. Vomiting came on early, with giddiness and staggering gait. The body became changed in colour very rapidly—the colour being between a slate and leaden hue. The eyeballs were of the same colour but of a lighter shade, the mouth and tongue exhibited the colour most markedly. The temperature was subnormal, the pulse quick and feeble, and the breathing occasionally interrupted with sighing respirations. The blood failed to give the spectrum of methæmoglobin. The symptoms passed off within twenty-four hours. During the illness, the man passed several green-coloured motions. The vomit was of a purplish-black colour—from the marking ink—and on analysis gave the reactions of aniline. Some of the ink was procured, and on being analysed was found to consist of hydrochloride of aniline and chloride of copper. The treatment consisted of stomach lavage and inhalations of oxygen, which gave the patient much relief.
Cases have been recorded of aniline poisoning in infants from absorption of the material from linen napkins, which were stamped with marking ink. Buchanan has seen lividity arise from the dry hydrochloride of aniline having been carried in a paper parcel in the waistcoat pocket for two or three days.
Post-mortem Appearances.—None characteristic.
Fatal dose.—Six drachms have proved fatal, probably less might do so.
Chemical Analysis.—Aniline may be separated from organic matter by alkalising and distilling the mixture.
1. If chloride of lime (bleaching powder) be added slowly to an aqueous solution of aniline, a deep purple colour is produced, which changes to brownish-red.
2. If strong sulphuric acid be added to aniline in a porcelain capsule it forms a dirty-white mass; on adding water and then potassium bichromate a bronze-green colour is produced, which changes rapidly to blue and then black.
3. If aniline be dissolved in excess of aqueous solution of phenol, and bleaching powder dropped into the mixture, a yellow streak changing to blue follows each drop.
4. Heated with corrosive sublimate a rich crimson colour is produced.
5. If aniline be mixed with a little chloroform and alcoholic solution of potash and heated, the peculiar odour of phenyl-isocyanide is given off.
Treatment.—As for nitrobenzene.
Fusel-oil, Amylic Alcohol, Potato-Spirit.—Fusel-oil, also known as amylic alcohol, is known by its unpleasant odour and burning taste; it acts like alcohol as an inebriant, giving rise to headache, giddiness, &c.
Nitro-glycerine.—In liquid or vapour, violent headache and throbbing in the temples are produced by this substance, which is used in the treatment of angina pectoris.
ACETANILIDE (ANTIFEBRIN),
PHENAZONUM (ANTIPYRIN),
AND PHENACETIN
These substances are used extensively as antipyretics. They have been known to cause poisoning when administered in large doses.
Symptoms.—The symptoms are principally those of depression, impairment of sight, vertigo, sleepiness, and unconsciousness; collapse, cyanosis, and loss of body temperature; the pulse and respiration are lowered. Antipyrin causes tumultuous action of the heart, and there may be erythematous or herpetic eruptions on the skin. Aniline derivatives, like sulphonal and other synthetic drugs, tend to destroy the red corpuscles of the blood, and decompose hæmaglobin, producing hæmatoporphyrin which appears in the urine.
Chemical Analysis.—Antifebrin may be extracted from an acid solution by chloroform; for antipyrin the solution should be alkaline.
Antifebrin gives the phenyl-isocyanide reaction on warming with alcoholic solution of potash and chloroform. Bichromate of potassium dissolved in strong sulphuric acid gives a red colour, changing to brown and dirty green; sodium nitrite and strong hydrochloric acid give a yellow colour, changing to green and blue; on evaporation the residue is orange, and turns red on addition of ammonia.
Antipyrin.—Heated with strong nitric acid and the liquid allowed to cool, a purple colour is produced; if water be added a violet precipitate is thrown down, and the filtered liquid will be purplish-red. Ferric chloride gives a blood-red colour, destroyed by a mineral acid. An aqueous solution of potassium nitrite and strong sulphuric acid gives a green colour.
Phenacetin is coloured yellow by nitric acid, the colour persisting when heated. It dissolves in sulphuric acid without change of colour. Boiled with hydrochloric acid, then diluted with water and chromic acid solution added, gives a deep red solution.
CHAPTER XI
SEDATIVE POISONS
Cardiac