Toxicology

“ They give certain reactions with a few group reagents, but they are recognised only by their effects upon living animals. As decomposition advances the more stable alkaloids are formed, but those which are poisonous, like the toxalbumoses, are readily converted by further processes of putrefaction or by chemical means into innocuous bodies. Toxins is the general term used in toxicology for these poisonous substances formed from animal tissues. ”

“ It was for that reason that I was enabled to administer an antidote without making an exact diagnosis. Now, as you are well aware, toxicology is a very strange study. Even common table-salt is a poison, and has caused death. ”

“ Age, idiosyncrasy, tolerance, and disease, all exert modifying influences on the action of a poison. The form in which the poison is swallowed and the quantity also determine its action. In the gaseous form, poisons act most rapidly and fatally. When in solution and injected hypodermically, they also act very rapidly. ”

“ In cases where the possibility of poisoning must be kept in view, and where matters may require to be procured for chemical analysis, it is essential to be sure that all instruments, vessels, and bladders used are scrupulously clean. ”

“ It is certainly true that if we should drink only chemically pure water, take only that [Pg 327] food which is free from all adulteration and infection, and breathe the purest air free from all organic matter living and dead, yet our excretions would contain poisons. ”

“ Remissions are most likely to [Pg 236] occur in slow poisoning with the metallic irritants, from fear of detection or cunning on the part of the poisoner to imitate the progress of disease. In nervous affections, all the symptoms must be taken into consideration, and these will be found to differ from those of any known poison. ”

“ Under the head of each poison an account will be given hereafter of the evidence in support of the discovery of it by chemical analysis in the blood, textures, and excretions. In the present place it is sufficient to state in general terms that the evidence is quite satisfactory in the instances of iodine, sal-ammoniac, oxalic acid, nitre, sulphuret of potassium, arsenic, mercury, copper, antimony, tin, silver, zinc, bismuth, lead, hydrocyanic acid, cyanide of potassium, carbazotic acid, sulphuretted-hydrogen, camphor, and alcohol. ”

“ Thus, in the course of his examination, the analyst has made a number of decoctions, in one of which the poison is certain to be. In each decoction there may be any one of several groups of poisons.
In which is it, and what is it? After all this patient labour the solution is still far off. It may be a ptomaine from poisonous fish or decayed meat, a deadly berry, or leaf, or root, a small quantity of morphia, or phosphorus, or lead, or arsenic, or antimony.
Each brew is tested in turn. ”

“ When a person dies from the effect of poisoning, it is simply because the system was unable to eliminate the offending substance and was exhausted in the effort. There is a tolerance of some substances which frequently results in chronic disease, and again it is shown in what is called the cumulative effect or acute disease.
“Those who would hold that a substance is at one time a medicament, and at another time a poison, have much trouble in drawing the line between the beneficial and the poisonous effect. ”

“ At some future time, with a more intimate knowledge of the way in which each poison acts upon the various forms of animal and vegetable life, it may be possible to give a truly scientific and philosophical classification of poisons—one based neither upon symptoms, upon local effects, nor upon chemical structure, but upon a collation and comparison of all the properties of a poison, whether chemical, physical, or physiological. ”

“ However brief and imperfect the foregoing historical sketch of the part that poison has played may be, it is useful in showing the absolute necessity of a toxicological science—a science embracing many branches of knowledge. ”

“ And, finally, when the poison has been supplied in too small a quantity to destroy life, eschars are produced, that is, certain superficial portions of the tissues are destroyed, which are afterward thrown off by the reparative process taking place in the healthy parts.
These three sets of instances admit of being treated according to the Method of Agreement. In all of them the metallic compounds are brought into contact with the substances which compose the human or animal body; and the instances do not seem to agree in any other circumstance. ”

“ Alkaline solutions are antidotes for the mineral acids; as soap in solution, a simple remedy, and always at hand. Lard, magnesia, and oil are antidotes for poisoning by arsenic; albumen,—in the form of the white of an egg,—milk, etc., for corrosive sublimate, and other mercurial preparations.
Antiseptics.—Medicines which prevent putridity in animal substances, and arrest putrefaction, when already existing. These are used both externally and internally. The chief specifics of this class are the acids, alcohol, ammonia, asafœtida, camphor, charcoal, chloride of lime, cinchona, ether, and opium. ”

“ But, if we are wise, we limit our dose of the second poison so that the toxic effects of both combined are at the minimum. If we take more of it, it produces toxic effects of its own beyond those necessary to counteract, so far as possible, the first poison. ”

“ Accum’s time, with some success; yet nothing is more certain than that a very large proportion of the food we eat, of the liquid we drink—always excepting good well-filtered water—and the medicines we take, not to say a word about the clothes we wear and the miscellaneous merchandise we use, is more or less adulterated with cheaper materials. Sometimes these are merely harmless; as flour, starch, annatto, lard, etc.; sometimes they are vigorous, destructive poisons—as red lead, arsenic, strychnine, oil of vitriol, potash, etc. ”

“ To vital agents then, the practitioner must principally look for succour; but before we can establish any general rules for the treatment of poisoning, it is essential to distinguish between the different modes in which poisonous substances produce their effects, or at least to determine the parts of the living system through which they act; for it will be found, that each poison has its own modus operandi, from which alone can be derived the particular indications of cure. ”

“ Secondly, in close connection with the uncleanliness of animal food we may consider its unwholesomeness. These waste products of the tissues to which I have referred are poisonous to us, and they usually take the form of uric acid. We have already our own waste-tissues, our own uric acid, to dispose of, and when we add to this poison of our own production the poisons produced by the animals we eat, we increase enormously the labours of our kidneys and digestive organs. ”

“ Pharmacology is a branch of biology; it is also closely connected with pathology and bacteriology, for certain drugs produce structural as well as functional changes in the tissues, and in germ diseases the peculiar symptoms are caused by foreign substances (toxins) formed by the infective organisms present in the body. The effects of many of these toxins bear a close resemblance to the action of certain well-known drugs, as in the case of tetanus toxin and strychnine, and are studied by the same methods of observation and research. ”

“ There are but few poisons which destroy life in a few minutes. Omitting the strong mineral acids, carbon monoxide, carbon dioxide, with the irrespirable gases,—Prussic acid, the cyanides, oxalic acid, and occasionally strychnine, are the chief poisons coming under this head.
B. Irritant Poisons (symptoms mainly pain, vomiting, and purging) .
Arsenic, antimony, phosphorus, cantharides, savin, ergot, digitalis, colchicum, zinc, mercury, lead, copper, silver, iron, baryta, chrome, yew, laburnum, and putrid animal substances. ”

“ There is, of course, less prima facie objection to those agents which consist of assimilable elements, such as are found making a part of healthy tissues. These are divisible into three classes,—foods, poisons, and inert, mostly because insoluble, substances. The food of one animal or of one human being is sometimes poison to another, and vice versa; inert substances may act mechanically, so as to produce the effect of poisons ”

“ It is only when they find their proper food, decaying matter, that they begin to multiply, and in that act they secret a poison, toxin, which is absorbed, and, entering the circulation, causes in the individual a special class of symptoms peculiar to that toxin, or poison. ”

“ The activity of the liver in destroying these poisons, and of the kidneys in eliminating them, are the physiologic processes which stand between the patient and death. In a very grave case of infectious disease, without this destructive and eliminative activity the accumulation of poison within the system would quickly reach a fatal point. The symptoms of the patient vary for better or worse in relation to the augmentation or diminution of the quantity of toxic substances within the body. ”

“ If there is the least doubt about the substance, do not assume the least risk, but destroy it at once. Many times the unknown contents of some bottle or package has been carelessly taken and found to be poison.
Careless and stupid people often take, by mistake, with serious, and often fatal, results, poisonous doses of carbolic acid, bed-bug poison, horse-liniment, oxalic acid, and other poisons. A safe rule is to keep all bottles and boxes containing poisonous substances securely bottled or packed, and carefully labeled with the word POISON plainly written in large letters across the label. ”

“ If the death has really taken place from disease, and not from poison, or if it has been caused by poison, and yet no definite hint of the particular poison can be obtained either by the symptoms or by the attendant circumstances, the analyst has the difficult task of endeavouring to initiate a process of analysis which will be likely to discover any poison in the animal, vegetable, or mineral kingdom. ”

“ The diseases which we find most difficult to cure, even by the most radical application of natural methods, are cases of drug-poisoning. Substances which are foreign to the human organism, and especially the inorganic, mineral poisons, positively destroy tissues and organs, and are much harder to eliminate from the system than the encumbrances of morbid materials and waste matter produced in the body by wrong habits of living only. ”

“ With regard to the commoner poisons, such as arsenic, corrosive sublimate, the mineral acids, oxalic acid, nux-vomica, and the like, it is a good general rule, that the symptoms, if violent from the beginning, must have begun soon after food, drink, or medicine has been taken. ”

“ Such accumulation of waste and morbid matter in blood and tissues creates the great majority of all diseases arising within the human organism. This will be explained fully in the following chapters which deal with the causation of acute and chronic disease.
More harmful and dangerous, and more difficult to eliminate than the different kinds of systemic poisons, that is, those which have originated within the body, are the drug poisons, especially when they are administered in the inorganic mineral form. ”

“ At first paralyzed or repelled, they after a time pluck up courage to attack the invading substances and carry on or renew their accustomed work of scavenging; they try to get rid of both poisons and poison-producers, and even acquire the power of forming substances (anti-toxins) which can neutralize the poison and allow the cells to devote their energy to doing their own proper work. ”

“ On attending to the effects which follow the application of a poison to the body, we perceive that they are sometimes confined to the part where it is applied, and at other times extend to distant organs. ”

“ Another species of poison, allied to the preceding in its effects and equally obscure in its nature, includes certain fluids of the human body after natural death, which are probably modified, if not even formed altogether, by morbid processes during life. Such poisons are the most frequent source of the dreadful cellular inflammation, often witnessed as the consequence of pricks received during dissection by the anatomist. ”

“ Another point of difficulty is the great individual variation in the susceptibility of animals. This is probably greater than when the poison is administered subcutaneously or intravenously. It necessitates the use of a large number of animals in making a determination of the toxicity of a gas. Again, the toxicity for different species may vary, and as the ultimate aim is a knowledge of the toxicity for man, a great many different species must be used. If the toxicity is widely different for different animal species, it is hard to arrive at a definite conclusion as to the toxicity for man. ”

“ The poison absorbed in the body can act unchanged from the place where it is stored. A number of poisons, however, undergo in the organism chemical change through which the action of the poison is partly lessened, rarely increased. ”

“ Equally true is it that the man or woman who makes use of such drugs as alcohol, opium, chloral, and such like, in an intemperate manner, contains these poisons in solution in the blood, circulating to every part of the body, and thus bathing and profoundly influencing the germ-cells. In consequence of this fact an acquired and habitual intemperance will seldom fail to leave its impress upon one or more of the offspring, either like the original vice or one very closely allied to it. ”