Foods.—The kinds of food which most frequently produce symptoms of poisoning are pork, veal, beef, meat-pies, potted and tinned meats, sausages, and brawn. Sausage-poisoning is common in Germany. It is not necessary that the food should be 'high' to give rise to poisoning. It may arise from the use of the flesh of an animal suffering from some disease, from inoculation with micro-organisms, or from the presence of toxalbumoses or ptomaines. Many diseases, such as diarrhœa, enteric fever, and cholera, and perhaps tuberculosis, may be caused by eating infected food. Trichiniasis may also be mentioned. Tinned fish often gives rise to symptoms of poisoning, and shell-fish are not uncommonly contaminated with pathogenic micro-organisms. Mussel-poisoning was formerly supposed to be due to the copper in them derived from ships' bottoms, but it is more probably the result of the formation of a toxine during life, and not after decomposition has set in. Milk, too, may give rise to gastro-intestinal irritation from the occurrence in it of chemical changes. There have been epidemics of poisoning from eating cheese containing tyrotoxicon. Ergotism from eating bread made with ergotized wheat is now rare, but pellagra from the consumption of mouldy maize, and lathyrism, due to the admixture with flour of the seeds of certain kinds of vetch, are still common in Southern Europe.
Symptoms.—The symptoms which result from the ingestion of poisonous meat are often very severe. In some cases their appearance is delayed from twenty-four to forty-eight hours. They may resemble those of an infectious disease or those of acute enteritis. Usually there are headache, anorexia, rigors, intestinal disturbance, pains in the back and limbs, and delirium. Sometimes the symptoms resemble atropine-poisoning, a condition due to ptomatropine.
Treatment.—Emetics, purgatives, stimulants, with hypodermic injections of strychnine and atropine along with stimulants.
XLVIII.—PTOMAINES OR CADAVERIC ALKALOIDS
Every medical man, before presenting himself to give evidence in a case of suspected poisoning, should make himself thoroughly acquainted with recent researches on the subject. Ptomaines are, for the most part, alkaloids generated during the process of putrefaction, and they closely resemble many of the vegetable alkaloids—veratrine, morphine, and codeine, for example—not only in chemical characters, but in physiological properties. They are probably allied to neurine, an alkaloid obtained from the brain and also from the bile. Some of them are analogous in action to muscarine, the active principle of the fly fungus. Some are proteids, albumins, and globulins. Ptomaines may be produced abundantly in animal substances which, after exposure under insanitary conditions, have been excluded from the air. Ptomaines or toxalbumins are sometimes found in potted meats and sausages, and are due to organisms—the Bacillus botulinus, the B. enteritidis of Gärtner, the B. proteus vulgaris, or the B. ærtrycke (which is perhaps the most common of all). The symptoms produced by the latter are usually vomiting, abdominal pain, pains in the limbs and cramps, diarrhœa, vertigo, coldness, faintness, and collapse. The symptoms of botulism are dryness of skin and mucous membranes, dilatation of pupils, paralysis of muscles, diplopia, etc. Articles of food most often associated with poisoning are pork, ham, bacon, veal, baked meat-pie, milk, cheese, mussels, tinned meats.
In a case of suspected poisoning, counsel for the defence, if he knows his work, will probably cross-examine the medical expert on this subject, and endeavour to elicit an admission that the reactions which have been attributed to a poison may possibly be accounted for on the theory of the formation of a ptomaine. There is practically no counter-move to this form of attack.