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ON THE CHARACTER OF THE EVI

DENCE AS TO THE INJURIOUS-
NESS OF ARSENIC AS A DO-
MESTIC POISON.

BY JAMES J. PUTNAM, M.D.,

OF BOSTON, MASS.

This communication is an attempt to place in as clear a light as possible, the credibility of the evidence that symptoms of arsenical poison may occur as a result of the ordinary exposures, such as are met with in domestic or civic life.

I shall not try to indicate the frequency with which such poisoning occurs, but only the possibility that it may occur; for the question as to frequency can only be satisfactorily answered when a large body of facts have been accumulated, especially those relating to the obscurer forms of chronic poisoning. The first thing to be done, would seem to be to disprove the opinion which has so much weight, even among those who would otherwise credit the evidence of domestic poisoning, that not enough arsenic could possibly reach the tissues to cause serious effects.

For this purpose I shall show: first, that urine analyses indicate beyond cavil that the exposures of civic life are a very frequent cause of arsenical contamination; next, that our knowledge of the laws of elimination indicates that the excretion of the small quantities which pass off with the urine day after day for months and years, in the case of many persons in the community, implies the presence by accumulation of much larger quantities in the tissues. The dangers attending domestic exposure might, in fact, be fairly compared with the dangers attending the medical use of arsenic, and I shall show that these dangers are usually underestimated. If in the cases of domestic exposure, the single doses are smaller, yet on the other hand, the period of exposure is much greater; the patient is not under the watchful care of a physician; the character of the arsenical compounds sometimes brings special dangers; the place of absorption is often the lungs and not the stomach ; and there is some reason to believe, that there are certain very chronic and exceptional forms of poisoning, following the repeated use of minute doses, with which we are not yet thoroughly familiar, and which, in the absence of signs of acute poisoning, are likely to be overlooked. The dangers attending the medicinal use of arsenic have been underestimated by physicians, partly because of their relative infrequency; partly because the first indications of them (œedema of the face, irritation of the mucous

membranes, etc.,) are so familiar, and usually so amenable to treatment, that they are hardly looked upon for what they are, namely, imperative signs that symptoms of more serious import are not far off (as shown by the experiments of Vaudrey).

Again, the effects of habituation, the storage of the arsenic in a temporarily innocuous form (albuminoid compounds of arsenic; Dogiel, International Congress, Copenhagen, 1886), and constitutional indifference to the poison confer as a rule such complete immunity, that those not so fully protected by nature, or with whom the protection ceases after a time, for one or another cause, stand in all the greater danger on account of the false impression of security which is spread abroad, and which makes physicians impatient of studying the obscurer indications of poisoning.

The most important collateral facts bearing on the question of the quantity of arsenic absorbed. in domestic poisoning cases, are, as above stated, those obtained by urine analyses, of which large numbers have been made by the chemists associated with Harvard University.'

To speak of only the most recent and conclusive series of experiments, Dr. C. P. Worcester, of Harvard University, a skilled chemist and with large experience in this particular analysis, has examined for my brother and myself one hundred and fifty urines, taken from patients most of whom presented certain obscure symptoms, but not such as would have justified the

diagnosis of arsenical poisoning, and has found. arsenic in more than thirty per cent., in quantities varying from a trace to upwards of .05 mg. to the litre.

About half of these patients were private, while the other half were from the clinic for Diseases of the Nervous System of the Massachusetts General Hospital, and many of the latter were chosen as presenting no arsenical symptoms.

These results conclusively show: first, that the community is exposed to arsenical contamination on a very large scale, so that the occasional occurrence of poisoning, due perhaps to special susceptibility, unusual exposure, failure of elimination, etc., need occasion no surprise, and ought to be carefully sought for by every physician; second, that the mere finding of arsenic in the urine in a doubtful case does not prove that the symptoms were of arsenical origin.

What does the elimination of these small quantities indicate as to the amount present in the tissues?

It was formerly believed that arsenic differed from lead in being eliminated rapidly and in not. uniting with the tissues. Both of these opinions are now disproved. Arsenic has been found in the liver bones (Gibb) six months after the cessation of a course of arsenical treatment (which, by the way, led to the patient's death); it has been found in the urine even nine months after the apparent removal of the patients from exposure in "domestic" cases; and Prof. E. S.

Wood has recently found traces in the urine as long as three months after cessation of a short course of arsenical treatment (these experiments are not yet concluded, and I quote a verbal statement only as relating to one or two cases).

Arsenic does then, in some cases at least, tend to accumulate, and the daily elimination of .03 to .3 mg. (gr. 6 to 6, computed by supposing two litres of urine to be excreted daily, and to contain two-thirds of the whole elimination of the arsenic), must indicate the presence in the tissues of quantities quite large enough to cause poisoning, provided it should become active all at once, or provided that for any reason the elimination should be checked.

That the effects of arsenic-like those of lead, and phosphorus-are in a measure dependent upon the action of the stored up poison, is shown. by the fact that the symptoms of medicinal poisoning often appear only when a given dose has been taken for some time, after which the patient. is apt to show an increased sensitiveness (though this is not regularly the case). In the case of lead it is a matter of common knowledge that sudden outbreaks may occur after lead drinking water has been used for a long time, as well as among the workers in lead mines. In the case of arsenic, it is quite common to find the paralytic symptoms breaking out days or weeks after a single large dose or repeated smaller doses.

Is the use of arsenic in maximum therapeutic doses unattended with danger?

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