LEAD. This is one of the most fearful poisons in the catalogue, on account of the numerous accidental ways in which it is introduced into the body, whether in the way of food or medicine, or in the various arts in which, in some form or other, it is used. Even where it does not produce death, its consequences are most pernicious.
The most common forms in which this substance is apt to be swallowed are the following : the acetate, litharge, ceruse, and the red oxide ; as also in water, wine, cider, vinegar, pickles, Sr.c. and in the form of vapour. Thus it finds its way into our food every where. In the arts, those who suffer chiefly from it are painters, lapidaries, glass grinders, workers in smelting houses, and in ceruse works and paint mills, makers ol shot, and so forth. It is this which renders it so important an object of investigation to medical men.
It is well known that wine was formerly mud. treated with lead in France, to correct undue acidity; but it is said that the practice has long been abandoned. Still, there is no doubt that, from design or inadvertence, it often finds its way into wine. When used in the metallic state in wines abounding in tartar, it forms an insoluble tartrite, which is precipitated ; so that if the wine is fined, little inconvenience follows. When the acetite is used, or the wine is acescent from acetous fermentation, the danger is considerable.
It is known to have been frequently found in cider, from the use of lead in the presses, but that practice has been rectified. In all cases it may be introduced into wine or cider ft onn shot remaining in the bottles after cleaning.
Some waters, kept in leaden cisterns, have been known to corrode them so as to become poisonous. This is par ticularly the case on long standing, or when vegetable matters are present at the same time.
The usual manner in which lead is introduced into cookery, is by means of vessels glazed with the glass of lead. Pickles preserved in this kind of earthen ware are frequently highly poisonous. Thus also fish, potted in vinegar, and many other articles in common use, become poisons. It is said that, in France, syrups and sweet cor dials are chit ified by means of acetate of lead. Children halve died from eating red wafers, which are coloured by means of the red oxide.
The methods by which it gets access to many of the artists employed on lead, are sometimes very obscui e.
In many cases it seems to produce its effect by acting on the skin. Thus lapidaries and glass-grinders become paralytic in the hands and arms, from the putty used in polishing, which is a mixed oxide of tin and lead. Many artizans probably suffer from mere exposure to vapours or dust of lead in some form or other. The medical ap plication of lead externally has produced the same effects, and must be considered a very unsafe practice.
The poisonous effects of lead sometimes come on quick ly, if the substance has been taken in quantity ; but inure generally the attacks are insidious and slow ; and very often, when the quantity is very small, the effects are so gradual, that the cause is not suspected.
The most ordinary symptoms are vomiting, chiefly at the beginning of the attack, pains in the abdomen rising to violent colic, and accompanied by retraction of the ex ternal muscles which is relieved by strong pressure, and constipation. There is no fever nor inflammatory action, but the attack of colic is generally followed by paralytic affections, and, commonly, of the arms. These are some times the only symptoms, but they affect other parts also, while there are tremors and shrinking of the muscles. These symptoms are commonly incurable, and they occur most frequently among artizans of various kinds, when the action of the metal in small quantities has been long continued.
The symptoms, on dissection, show that there is in flammation ol the mucous membrane, with occasional slight extravasations of blood, but only when a large quantity of the poison has been taken at once. In other cases, nothing has been found but contractions of the colon.
Treatment of the patient. if the poison has been just swallowed, 'hc first thing to be done is to give sulphate of soda, or magnesia, ith much water. The sulphate of lead thus produced does not appear noxious.
Otherwise, the practice is to give purgatives of senna, or salts, or both, or of other medicines, according to the state of the bowels. Opium is also found necessary to relieve the spasms and constrictions of the intestines But for the more minute details of this practice we must refer to our article MEniciNE The paralytic affections generally defy all attempts at a cure