Text-book of forensic medicine and toxicology

Chapter IV: Metallic Irritants (2)

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_Post-mortem Appearances._--The mucous membrane of the throat, gullet, and stomach is inflamed, and in some places softened and corroded. Aphthous-looking spots are not infrequently found on the mucous membrane of the stomach, and these may also be observed on the throat and on the small intestines. The liver has been found in some cases of chronic poisoning, where the fatal termination has been for some time retarded, enlarged, and its structure so soft as to be easily broken down. Fatty degeneration of the internal organs has been found after protracted fatal administration of the drug. It is stated that in Brunswick the fatty livers of the geese are produced by the judicious administration of antimony. The appearances above detailed may be more or less absent or present, according to the time that may have elapsed from the swallowing of the poison to the time at which death has occurred.

At the _post-mortem_ examination on the body of Mr. Bravo, poisoned with tartar emetic in 1876, the mucous surfaces of the stomach and duodenum were found pale and yellowish. Ulcers were present in the cæcum, and the rest of the large intestine blood-stained, but not ulcerated. Stevenson records the _post-mortem_ appearances of the bodies of three women poisoned by tartar emetic (_B. M. J._, 1903, vol. i. p. 873). They are of peculiar interest in reference to the preservative action of antimony upon the bodies of those poisoned by it. In the case of M. E. Marsh, upon whose body the examination was made eight days after death, there was no odour of putrefaction, the bowels were in a condition of acute catarrh and streaky congestion without ulceration.

The body of Bessie Taylor had been buried for twenty-one months; ordinary putrefactive changes were absent, and with the exception of the integuments, it was in a remarkably good state of preservation. The alimentary canal showed acute non-ulcerative gastro-enteritis, the stomach and duodenum were of a cinnabar-red colour, the jejunum also in patches. The ileum was covered with orange-red mucus in its lower portion, and there was an orange-coloured patch twelve inches above the ileo-cæcal valve. The patch on analysis was proved to contain antimonious sulphide. Similar orange patches were present in the colon and upper portion of the rectum. There were no ulcerations, but the mucous membrane of the intestines was of a dull cinnabar-red colour.

The body of Mary J. Spink was exhumed five years after burial, and presented a life-like aspect; there was no putrefactive odour, and no larvæ present. The stomach and intestines were of a cinnabar-red colour; there were no ulcerations; the intestines contained orange-coloured mucus.

Elimination of Antimony from the System

Antimony, taken in a large dose, or in small doses frequently repeated, appears to be rapidly absorbed, and then eliminated from the system by the kidneys. Dating from the time at which the poison was swallowed, it will be found in the organs of the body in the following order:--

1. Stomach and bowels, but slightly in the liver.

2. Absent from the stomach, but present in the liver,
spleen, and kidneys--traces in the blood.

3. Present in the fat and bones, with traces in the liver,
fæces, and urine.

4. The period required for its complete elimination from the
vital organs varies from fifteen to thirty days.

In other words, the presence of antimony in the stomach and intestines points to the recent administration of the poison; and its absence from those organs, and presence in the others above mentioned, to a more remote period of administration. It has been suggested that in some cases the poison may be eliminated by the mucous membrane of the stomach. This assumption has been proved to be correct, for it has been shown that antimony may be found in the stomach after the inhalation of antimoniuretted hydrogen.

_Fatal Dose._--It is impossible to state with certainty the exact amount of antimony--tartar emetic--which may prove fatal, as recoveries have taken place even after an ounce had been taken. Large doses are uncertain in their effects, as the severe vomiting which they produce generally helps to get rid of the poison. In small doses, death may result from the depressing action which it exerts over the heart.

_Fatal Period._--From a few hours to several weeks, and even months.

_Treatment._--Promote vomiting by the administration of warm water, or warm greasy water, or the stomach may be washed out with a syphon tube, unless the chloride of antimony is the poison, and then give tannic acid in drachm doses in warm water, or any vegetable infusion containing tannin--viz., tea, oak bark, or cinchona bark. Demulcent drinks may be administered, and warmth applied. Opium may be given to relieve pain, and stimulants for the depression.

The Detection of Antimony

Prepare the solutions of the liver and other solid organs, and also the contents of the stomach, as described under the detection of arsenic, using tartaric acid instead of hydrochloric acid. Through a portion of one of the solutions, obtained by filtration or dialysis, pass a current of sulphuretted hydrogen, which will produce, if antimony be present, an orange-coloured precipitate of the sulphide of antimony. The precipitated sulphide is dissolved by hot hydrochloric acid with the evolution of sulphuretted hydrogen; and if the resulting solution be poured into water, a white precipitate is formed of oxychloride of antimony, soluble in tartaric acid. Chloride of bismuth is precipitated when poured into water, but the precipitate is turned black by sulphide of ammonium, the antimonial orange-red; the precipitate of bismuth is not soluble in tartaric acid, the antimonial is soluble.

Marsh‘s and Reinsch‘s processes may also be used for the detection of antimony. The former is, however, open to the objection that antimony, when present in any quantity, rapidly precipitates on the zinc in the form of a flocculent black deposit, while the issuing gas is found to contain only traces of the metal.

Reinsch‘s process is, however, very delicate, and its application is in every respect similar to that in use for the detection of arsenic. The acid liquid should, however, be boiled down to a small bulk with the copper, before a conclusion is drawn as to the entire absence of the metal.

Table giving the Characteristic Reactions of Antimonial
and Arsenical Deposits on Copper.

It may be noted that mercury likewise yields a deposit on copper with Reinsch‘s process; but the coating is in this case either of a grey colour or white, and silvery on the application of friction. When the coated copper is heated in a glass tube, there is a sublimate of metallic mercury readily aggregating into globules on being rubbed with a glass rod. If the deposit is trifling in quantity, a magnifying-glass should be used to identify the metallic globules. This test at once distinguishes a deposit on copper due to mercury from that produced under similar conditions by arsenic or antimony.

_Quantitative Analysis._--Take a measured quantity of the suspected liquid and precipitate thoroughly with sulphuretted hydrogen. Wash, dry, and weigh precipitate. One hundred parts equal 202.78 parts of crystallised tartar emetic.

MERCURY

Metallic mercury possesses no toxicological interest, as it appears to be almost inert, even in very large doses. If applied to the skin in a finely-divided state, as in mercurial ointment, or internally, as blue pill, its toxic effects may be produced. The vapour given off from the metal is highly poisonous, producing salivation, emaciation, and death. A singular accident of poisoning by mercurial vapour occurred on board H.M.S. _Triumph_ in 1810, owing to the bursting of bladders containing large quantities of the metal; in three weeks 200 men were affected with salivation, etc., nearly all the cattle on board died, as well as the mice, a dog, and a canary-bird.

Corrosive Sublimate

This is the most important of the preparations of mercury. It occurs either in crystalline masses of prismatic crystals or as a white powder. It is now known among chemists as the perchloride, though it is frequently spoken of as the bichloride, chloride, and oxymuriate of mercury. It has a powerful metallic and styptic taste, and is soluble in about sixteen parts of cold water and three of boiling water. Alcohol and ether readily dissolve it, the _latter having the power of abstracting it from its solution in water_. This property of ether is of importance as a means of separating corrosive sublimate from its solution in other liquids. It is important to remember that corrosive sublimate is soluble in alcohol (R. _v._ Walsh). The liquor hydrargyri perchloridi of the Pharmacopœia contains half a grain of the salt to a fluid ounce of water. Half a grain of the muriate of ammonia is added to increase the solubility of the mercurial salt. Applied externally to the unbroken skin, corrosive sublimate has caused death in several cases, the symptoms being almost identical with those which follow the entrance of the poison into the stomach. Toxic symptoms have followed intra-uterine or vaginal injections of solution of perchloride of mercury, also when it has been used to wash out abscess cavities. Acute poisoning, in some cases fatal, has resulted from the external application of corrosive sublimate to ulcers and tumours.

Symptoms of Poisoning by Corrosive Sublimate

_Acute._--The symptoms come on almost immediately the poison is swallowed. A strong metallic coppery taste in the mouth is experienced, and a choking sensation in the throat. Pain of a burning character is felt, extending from the mouth to the stomach, followed by nausea and vomiting of stringent mucus, more or less tinged with blood, and violent purging, the evacuations being also mixed with blood and mucus. The pulse is feeble, quick, and irregular; the countenance flushed or pale, and the tongue white and shrivelled. This appearance of the tongue is not present in all cases. Broncho pneumonia may occur. The skin is cold and clammy, and the functions of the kidneys are altered and albuminuria present, there being in many cases complete suppression of urine. As is the case with other irritant poisons, the symptoms and effects produced admit of considerable variation. Thus, there may be no pain in the stomach, and no purging. Salivation is present in some cases, but chiefly in those in whom the fatal termination is somewhat prolonged. This sign is not infrequently absent. Poisoning with corrosive sublimate differs from arsenical poisoning in the following particulars:--Corrosive sublimate has a distinct metallic taste, arsenic is almost tasteless; the symptoms in the former supervene immediately the poison is swallowed, in the latter there is a short delay. The discharges in corrosive sublimate are more frequently bloody than in arsenic poisoning.

_Chronic._--The symptoms present in this form of poisoning are modified by the size of the dose, and the interval allowed to elapse between each dose. Nausea, followed by occasional vomiting, and pains in the stomach, are complained of by the patient. There is general constitutional disturbance, with anæmia and cachexia, and consequent mental depression. Salivation, as might be expected, is a more prominent symptom than in acute poisoning; but the salivation may be intermittent--that is, it may cease and then reappear, even after the lapse of months, without an additional dose of mercury having been given in the interval. Salivation may also come on in the course of certain diseases, attacking the salivary glands, and it may also be produced by other causes--pregnancy, etc. The glands of the mouth become swollen and painful, the gums tender, and the teeth loosened fall out of the mouth. Periostitis of the jaw may occur. The breath has a peculiar, offensive smell, the bowels are irritable, and diarrhœa is not infrequently present. It must be borne in mind that in certain diseases--granular disease of the kidney--the smallest dose of any mercurial preparation may produce profuse ptyalism. And the toxicologist must be careful not to mistake the affection known as _cancrum oris_, or “the canker,” most common in delicate, ill-fed children and adults, for the effects of mercury. The nervous system is more or less affected, neuralgic pains and mercurial tremors being present in many cases. The tremors commence in the tongue and face and spread to the arms and legs--they are similar to those of paralysis agitans; at first they are invoked by exertion, finally they become continuous; they cease during sleep. Paralysis may also occur, especially in those exposed to the vapour of mercury. Habit appears to exert some influence on the action of corrosive sublimate, if we may accept the story of the old man of Constantinople, who for thirty years took large doses till his daily allowance was a drachm, and then died at the respectable age of one hundred years.

_Post-mortem Appearances._--The morbid appearances are chiefly confined, as is the case with arsenic, to the stomach and bowels; but the corrosive action of the mercurial sublimate is more marked. Inflammation more or less intense is always present in the stomach, the mucous membrane of which may be found of a slate-grey colour, corroded, and so soft as to scarcely admit of the removal of the organ without tearing it. The cæcum and rectum are also sometimes found inflamed, and the mucous membrane softened. Perforation of the stomach is very rare, only one case having been recorded in which this was present. The mouth, throat, and gullet may also present signs of the action of the poison similar to those just described as seen in the stomach. Patches of pneumonia are present in the lungs of some cases, and the kidneys show coagulative and desquamative nephritis.

_Fatal Dose._--The smallest dose was _two grains_ in the case of a child, but the exact amount to cause death in an adult has not been accurately determined. Recovery has taken place after one hundred grains has been taken.

_Fatal Period._--From half an hour to five days. No exact time can be stated. In one case death took place on the twelfth day after swallowing seventy grains of the perchloride.

_Treatment._--Vomiting, if present, must be encouraged; if absent, it must be produced by emetics--zinc sulphate or cupric sulphate, followed by copious draughts of warm water. The hypodermic injection of ¹/₂₀ to ⅒ grain of apomorphine may also be used to produce vomiting. Albumen, the white of egg, or vegetable gluten produced from flour by washing it in a muslin bag, should be given. The albuminate of mercury so formed should be quickly removed by an emetic or lavage by means of a soft tube and funnel in mild cases, as it is soluble in excess of albumen, and may be digested or absorbed. The rapid removal of the poison from the stomach, however, is the end to which all our exertions must tend. The forcible use of the stomach pump should not be employed if it can possibly be avoided, as it may greatly injure the softened mucous membrane of the gullet and stomach. Opium may be given to relieve pain, and opium enemata to relieve purging and tenesmus.

=Calomel=

Calomel, or the subchloride of mercury, is not used as a poison. In large doses it may act as an irritant poison, and death has not infrequently occurred even from comparatively small doses. Profuse salivation and gangrene of the mouth have resulted from its use, and cases are recorded of death resulting from these. In many cases idiosyncrasy appears to modify, more or less, the action of this preparation of mercury. The poisonous effect of calomel has been attributed to--(1) Adulteration with corrosive sublimate. (2) Conversion of the calomel into corrosive sublimate by the action of the hydrochloric acid of the gastric juice.

_N.B._--The free acid of the gastric juice is probably in too small a quantity to materially alter the composition of the calomel.

=Ammonio-Chloride of Mercury=

White precipitate may, if taken in large doses, produce alarming effects, but it cannot be regarded as an active poison. Pavy‘s experiments on rabbits indicate that it is a more powerful poison than was formerly thought to be the case. Its action is that of an irritant, accompanied with, in some cases, severe salivation.

=Red Precipitate=

Red oxide of mercury possesses poisonous properties, but it is seldom employed as a poison. The symptoms most frequently present are vomiting, coldness of the surface of the body, stupor, pain in the abdomen, and cramps of the muscles of the lower extremities. The vomited matters are generally mixed with some of the red oxide.

=Cinnabar. Vermilion=

A compound of sulphur and mercury in the form of a dark red crystalline mass is known as cinnabar; and to the same substance reduced to a fine powder the name vermilion has been given. It is used as a red pigment. It can scarcely be considered as a poison, Orfila asserting that it is not poisonous. The vapour of this substance appears, however, to be capable of producing severe symptoms, and in one case, profuse salivation resulted from the application of the vapour to the body.

=Cyanide of Mercury=

This substance, though an active poison little inferior to corrosive sublimate, is seldom used as such, probably from its being better known to chemists than to the general public. It differs from corrosive sublimate in having no local corrosive action. It has been supposed, but proof is wanting, that its injurious effects are due to its decomposition by the acids of the stomach and the formation of prussic acid. Death has occurred in nine days from a dose of ten grains. It acts as an irritant. The sulphocyanide of mercury is used in the manufacture of the toy known as Pharaoh‘s serpents.

=Turbith Mineral=

A powerful irritant poison, but seldom used. A drachm has caused death in a boy sixteen years of age. Coldness of the surface, burning pain in the stomach and bowels, with other symptoms of irritant poisoning, were present. After death, the mucous membranes of the throat, stomach, and bowels were found considerably inflamed.

=Nitrates of Mercury=

These substances--the nitrate and sub-nitrate--are used in the arts for various purposes. They act as powerful irritant poisons, with symptoms and _post-mortem_ appearances not unlike those before described when speaking of corrosive sublimate and other irritants.

_Chemical Analysis_:

Table showing the Reaction of Mercuric and
Mercurous Salts with Reagents

-------------------------------+------------------------------------
Mercuric Salts
-------------------------------+------------------------------------
1. With solution of iodide of | 1. Bright scarlet precipitate,
potassium. | soluble in excess.
|
2. With potash solution. | 2. Bright yellow precipitate.
|
3. With hydrosulphuret of | 3. First a yellowish and then a
ammonia. | black precipitate is produced.
|
4. Heated in a reduction tube.| 4. It melts, boils, is volatilised,
| and forms a white crystalline
| sublimate.
|
5. With ether. | 5. It is freely soluble in ether;
| and the ethereal solution, when
| allowed to evaporate
| spontaneously, deposits the salt
| in white prismatic crystals.
|
6. Heated with carbonate of | 6. Globules of metallic mercury
soda in a reduction tube. | are produced.
-------------------------------+------------------------------------
Mercurous Salts
-------------------------------+------------------------------------
1. Hydrochloric acid. | 1. A white precipitate of calomel,
| blackened on addition of ammonia.
|
2. Potassium iodide solution. | 2. Green precipitate.
|
3. Caustic potash or soda | 3. Black precipitate of mercurous
solution. | oxide.
-------------------------------+------------------------------------

=Detection of Mercury in the Tissues and in the Contents of the Stomach.=

Mercury is particularly liable to be absorbed by the tissues; it also readily combines with various organic substances, gelatine, albumin, &c.

_A._--If the contents of the stomach are under examination, they should be diluted with distilled water, filtered, and the residue pressed and reserved for further examination.

The liquid thus obtained may be concentrated, and, while still warm, slightly acidified with hydrochloric acid. A slip of zinc foil, with a piece of gold foil twisted round it, is then introduced. If mercury be present, the gold will, sooner or later, lose its yellow colour, and its surface become white and silvery, while the zinc is wholly or partially dissolved. The gold being removed, separated from the zinc, washed first with water and then with ether, is divided into two equal parts. One half may be heated in a reduction tube, when it will yield a sublimate of metallic mercury, identified by the spherical form of the globules under a magnifying-glass, and their metallic reflection and complete opacity. The other half of the gold may be treated with nitric acid and heated, which will dissolve off the mercury. The resulting solution, after expelling the excess of acid by evaporation, will give a scarlet precipitate with iodide of potassium soluble in excess; and, with protochloride of tin, a black precipitate of metallic mercury.

_B._--For the detection of mercury in the insoluble form, the residue from _A_ is dried; or, if the tissues are under examination, they should be finely divided, and freed from superfluous moisture. In either case, the substance is boiled in moderately strong nitric or hydrochloric acid (about one part of acid to four of water). After digestion for some time, the liquid is filtered, concentrated, and tested as in _A_. When there is reason to infer the presence of corrosive sublimate in considerable quantity in an organic liquid, advantage may be taken of the solubility of the salt in ether, and the power possessed by this liquid of abstracting it from its aqueous solutions. The liquid is agitated with an equal volume of ether, the ethereal solution poured off and allowed to spontaneously evaporate, when the corrosive sublimate will be left in white silky prisms, yielding all the characteristic reactions of the salt. In obscure cases of salivation, the saliva should be examined as follows: Take about two drachms of the saliva, acidulate with pure hydrochloric acid, and immerse in the mixture a very small piece of copper gauze attached to a platinum wire, and set aside in a warm place for some hours. If mercury be present, the copper will be covered with a white coating; this should be washed and heated in a reduction tube, when globules of mercury will be formed, and examined with a lens.

_C._--Mercury in solution may be detected by Reinsch‘s process. On boiling with pure copper foil after acidifying the solution with hydrochloric acid, the mercury is deposited on the copper in the metallic state, as a whitish silvery film, which can be polished to a silvery mirror surface. On washing the film in water, ether, and absolute alcohol and allowing it to dry, then subliming it in a reduction tube by the aid of heat, the mercury deposits on the cool part of the tube in the form of minute globules, which may be easily recognised through the microscope. If a small crystal of iodine be now placed in the tube and gently warmed so as to volatilise it, but not the mercury, and the tube be left to stand for a short time, the iodine combines with the mercury to form the scarlet iodide, the colour of which renders it easy of recognition.

According to Bonnewyn, the presence of an extremely small quantity of corrosive sublimate (¹/₅₀₀₀₀) in calomel may be detected by immersing a clean knife blade, moistened with alcohol or ether, in the suspected calomel. A black spot is formed on the steel very difficult of removal. No spot is formed when the calomel is pure.

LEAD

Metallic lead is not poisonous; but it appears probable that when it is acted upon by the acids of the intestinal secretions, it may become so changed as to produce unpleasant symptoms. Any salt of lead is poisonous when in a condition to be absorbed into the system.

Sugar of lead and white lead are alone important, and will therefore be briefly considered.

=Sugar of Lead=

Acetate of Lead. Subacetate. Goulard‘s Extract

_General Character._--The acetate of lead, better known as sugar of lead, is not unlike loaf-sugar in its general appearance. It is usually met with in the form of solid crystalline masses of a white or brownish-white colour. To the taste it is sweet, a metallic astringent taste being left in the mouth. Acetate of lead is soluble in water and in alcohol. The subacetate is a more active poison than the neutral acetate. Sugar of lead is popularly considered as an active poison, but this does not appear to be the case. Sir R. Christison gave eighteen grains daily in divided doses for eight or ten days with no other unpleasant symptoms than slight colicky pains in the abdomen. Lead is probably eliminated from the system by the urine, and also by the milk; but there is reason to believe that when once deposited in the body, some considerable time is required for its complete elimination. Dr. Wilson is of opinion that in chronic lead poisoning the lead is more largely deposited in the spleen than in any other organ of the body. This organ should therefore always be carefully examined in suspected cases of poisoning by this metal.

_Goulard‘s Extract_ is a solution of the subacetate of lead. It may be of a reddish colour, from the employment of common vinegar in the place of pure acetic acid in the manufacture.

_Goulard‘s Lotion_ is the extract diluted with water.

=White Lead=

White lead, carbonate of lead, ceruse, or kremser white, is used as a pigment. It is generally in the form of white, heavy chalky masses, insoluble in water, and, when taken in large doses, poisonous. It is this substance which, in the majority of cases, causes chronic lead poisoning, or _painter‘s colic_.

The _chloride_ and _nitrate_, the oxides, _litharge_ and _red lead_, are all poisonous; but the _sulphate_, due probably to its insolubility, appears to be inert.

Lead poisoning may result from--

1. Constant contact with lead and its salts in manufactories.

2. Its use in the arts and as a pigment. The injurious effects of this substance are strikingly seen among painters, the makers of glazed cards, and the workmen engaged in preparing Brussels lace--this material being whitened by beating white lead into it. All thus employed are liable to suffer more or less from chronic poisoning.

3. Its application to the surface of the body in the form of ointment, plasters, cosmetics, and hair-dyes.

4. Drinking water impregnated with lead, from being stored in leaden cisterns or conveyed in leaden pipes.

“The action of water upon lead is much modified by the presence of saline substances. It is increased by chlorides and nitrates, and diminished by carbonates, sulphates, and phosphates, and especially by carbonate of lime, which, held in solution by excess of carbonic acid, is a frequent ingredient of spring and river water. But water highly charged with carbonic acid may become dangerously impregnated with lead, in the absence of any protecting salt, in consequence of its solvent power over carbonate of lead. In general, water which is not discoloured by sulphuretted hydrogen may be considered as free from lead; but there are few waters which have passed through leaden pipes, or have been retained in leaden cisterns, in which a minute analysis will not detect a trace of the metal; and were it not for the great convenience of lead, iron pipes and slate cisterns would, from a sanitary point of view, be in all cases preferable.

“Another case of contamination by lead may arise from electric action, as where iron, copper, or tin is in contact with or soldered into lead; and in these cases, owing to the action of alkaline bases as well as of acids upon the lead, danger may occur when it is thrown into an electro-negative as well as into an electro-positive state.

“Cisterns are sometimes corroded and their bottoms are perforated by pieces of mortar having dropped into them, the lime of which has caused the oxidation of the metal and a solution of the oxide.”

5. Lead may also find its way into the system by means of the food. Farinaceous foods, chocolate, and tea may become contaminated if lead wrappers be used; and confectionery from the use of lead chromate as a colouring agent. The use of leaden vessels in the manufacture of cider is attended with danger, and also the keeping of pickles in glazed earthenware jars. The celebrated “Devonshire Colic” was the result of cider-making in leaden vats. Beer may be contaminated with lead if allowed to stand in leaden pipes overnight. Rum has been known to have been dangerously impregnated with lead, leaden worms having been used attached to the stills. Many tobacconists are in the habit of using lead foil to wrap up their tobacco and snuff; this practice has resulted in several cases of chronic lead poisoning. Soda and Seltzer waters may contain lead when kept in syphons with leaden caps or valves.

6. Acute and subacute cases of poisoning occur from the taking of lead in the form of diachylon pills to procure abortion.

=Symptoms of Poisoning by Lead=

_Acute._--A metallic taste in the mouth, accompanied with dryness in the throat and intense thirst, is experienced by the patient soon after the poison is swallowed. In some cases, however, _two or more hours_ may elapse before the effects of the poison begin to show themselves. Vomiting may or may not be present. Twisting colicky pains are felt in the abdomen, relieved in some cases by pressure. The paroxysms of pain may be separated by intervals of ease. The bowels are, as a rule, obstinately confined, and the fæces are of a dark colour, from the formation of the sulphuret of lead. The skin is cold, the pulse quick and weak, and there is considerable prostration of strength. In some cases the patient suffers from cramps of the calves of the legs, and sometimes, in protracted cases, paralysis of one or more of the extremities may supervene. The effect on the nervous system, headache, temporary blindness, is marked by giddiness, and stupor, in some cases delirium even resembling acute mania, terminating in coma, or convulsions and death. Albuminuria may occur.

_Chronic._--This form of poisoning generally occurs among painters, manufacturers of white lead, pewterers, and others. The early symptoms are those of ordinary colic, only more severe. The patient generally complains, in the first instance, of feeling unwell, and of general debility. He then suffers from pain of a twisting, grinding nature, felt in the region of the navel, the abdomen being retracted and hard. The bowels are obstinately confined. The appetite becomes capricious, and may be entirely lost. The mouth is parched, the breath fœtid, the countenance sallow, the skin dry, and general emaciation sets in. A nasty sweetish metallic taste in the mouth is present in most cases. Not infrequently the subjects of lead poisoning experience a peculiar form of paralysis of the upper extremities, well known as “dropped hand.” It appears that this condition is the result of paralysis of the extensor muscles of the wrist, the long supinator escaping. In other cases the muscles of the shoulder girdle or pelvic girdle and legs may be affected. Acute general paralysis has occurred in workers with lead, and may prove fatal. Optic neuritis and optic atrophy occur in some cases. Persistent headache may be present in others. The muscles undergo a form of fatty degeneration. The lead appears to act primarily on the muscles, then on the nerves, and lastly on the nerve centres. The absorption of lead causes marked anæmia with degeneration of the red corpuscles, which show marked punctate basophilia. One other symptom of importance has yet to be noticed. The gums, at their margins where they join the teeth, present a _well-marked blue line, absent where a tooth has been removed_. This is not present in all cases, but it should be looked for. Chronic lead absorption produces cardiovascular changes with arterio-sclerosis, valvular degeneration, cardiac hypertrophy, and chronic renal changes with albuminuria. Closely associated with these conditions are saturnine arthritis and gout. The effects upon the vessels may predispose to cerebral hæmorrhage or lead encephalopathy. Cicconardi suggests as a method of diagnosis in lead poisoning, where the cause of the colic is uncertain, to paint the skin with a 6 per cent. solution of sodium sulphite. If lead be the cause the painted part will become darkened in colour.

_N.B._--The symptoms produced by white lead--carbonate
of lead--are those of _colica pictonum_, or _painter‘s colic_,
described under the head of Chronic Lead Poisoning.

_Post-mortem Appearances._--In acute poisoning the mucous membrane of the stomach and intestines is inflamed, and is in some cases covered by layers of white or whitish-yellow mucus, more or less impregnated with the salt of lead swallowed. Corrosion of the mucous membrane may occur if the dose be large, and this condition is more frequently present when the neutral salt is taken.

In chronic poisoning there are no constant _post-mortem_ appearances. The muscles of the paralysed extremity are usually found flaccid, of a cream colour, and the subject of fatty degeneration.

_Fatal Dose._--Sugar of lead is not an active poison, recovery having taken place after one ounce had been swallowed.

_Fatal Period._--Uncertain.

_Treatment._--The stomach should be emptied by means of the pump or syphon tube, followed by the free administration of the sulphates of soda and magnesia. The carbonates should not be given, the carbonate of lead being poisonous. Vomiting should be promoted, and a powerful cathartic administered. Albumen and milk should also be given, as these precipitate the oxide. In the chronic form of poisoning, the iodide of potash and aperients, notably the sulphate of magnesia, should be administered. Dixon Mann does not consider that iodide of potash is of any value as an eliminator of lead, as the latter forms a stable compound with the tissues. Sulphur baths are also useful in removing the lead from the system. Lately the galvanic bath has been tried with great success. By way of _prophylaxis_, it has been recommended that all those engaged in lead manufactories, or who are obliged to handle this metal frequently, should partake largely of lemonade made with sulphuric acid, should not take their meals in the factories, or without well washing the hands.

_Chemical Analysis_.--When the solid acetate is heated on platinum foil, it melts, then solidifies, becomes dark in colour, and gives off fumes of acetic acid.

The following are the liquid tests for lead in solution:

1. Dilute sulphuric acid gives a white precipitate of the sulphate, which is insoluble in nitric, but soluble in hydrochloric acid, in excess of caustic potash solution, and in ammonium acetate solution.

2. Solution of potassium iodide gives a yellow precipitate, soluble in boiling water and caustic potash solution.

3. Sulphuretted hydrogen, or ammonium sulphide, gives a black precipitate.

4. Potassium bichromate a yellow precipitate.

=Detection of Lead in Organic Mixtures=

The contents of the stomach or vomited matters must be diluted with water and filtered. The residue left on the filter, washed with distilled water, should be set aside for further examination; the filtrate and washings acidified with nitric acid. A current of sulphuretted hydrogen passed through the solution will then throw down the whole of the lead, should any of that metal be present, in the form of a brownish-black sulphide, which may be collected on a small filter and dried. The sulphide, boiled with dilute nitric acid, is partly converted into insoluble sulphate, and in part dissolved as nitrate. The carefully neutralised solution may be either tested at once or carefully concentrated. In either case, the production of a bright yellow precipitate, with a solution of bichromate of potash, and a similar one with a solution of iodide of potassium, may be taken as conclusive of the presence of lead. The portion of lead deposited as sulphate will be found to be soluble in a solution of pure potash, the resulting liquid giving a brown-black precipitate on the addition of sulphide of ammonium.

The insoluble residue left on the filter should be incinerated in a porcelain crucible, either with or without nitric acid, care being taken not to raise the temperature more than is necessary to produce the desired effect: the carbonised mass boiled with dilute nitric acid evaporated to dryness, extracted with distilled water, and then filtered, the filtrate tested as before mentioned. It is often useful, as a preliminary test for the presence of lead in a soluble form, to dip a piece of bibulous paper into the clear liquid obtained by submitting the contents of the stomach or vomited matters to filtration, and then exposing the paper to the action of a current of sulphuretted hydrogen. If lead be present, blackening of the paper will take place.

To detect the lead in the urine and fæces, Dixon Mann advised the urine to be evaporated to the consistency of gruel, and the fæces to be mixed with distilled water to a similar consistence; the organic matters are then to be destroyed with hydrochloric acid and chlorate of potash with the aid of heat, and the solution filtered. The filtrate is then placed in a cell with a parchment bottom, and this into another cell containing distilled water acidulated with sulphuric acid. Two pieces of platinum foil are now placed in the inner and outer cells, separated by the parchment; that in the inner cell is connected with the cathode, that in the outer with the anode of four Grove cells, and the current closed for several hours. The lead, if present, is deposited on the platinum connected with the cathode.

The magnesium method (Marsden & Abram) is useful. A strip of pure magnesium is placed in the urine, to which has previously been added ammonium oxalate, about 1 gramme to 150 c.c. Lead, if present, is deposited on the magnesium in about half an hour, but it may take some hours. The strip is washed in distilled water and dried--warmed with a crystal of iodine the yellow iodide will form; or the deposit may be dissolved in HNO₃ and tested in the usual way.

Goadby recommends inoculating the urine with bacillus coli, which during its growth produces H₂S; this precipitates any lead as sulphide. After filtering, the filtrate is dissolved in a small quantity of 10 per cent. nitric acid and tested by the usual methods.

Recapitulation of the Leading Facts with regard to
Poisoning by Lead
--------------------+-------------------------------------------
ACUTE POISONING.--SYMPTOMS, ETC.
--------------------+-------------------------------------------
Action on alimentary| Sweet metallic taste in mouth. Vomiting,
canal. | constipation, burning twisting pain in
| the belly. Inflammation of canal.
|
|
|
Circulation. | The pulse lowered, and tendency to death
| from syncope. Anæmia.
|
Nervous system. | Neuralgic pain, convulsions, cramps,
| paralysis, &c.
--------------------+-------------------------------------------
CHRONIC POISONING.--SYMPTOMS, ETC.
--------------------+-------------------------------------------
Mouth and alimentary| Sweet metallic taste; blue line at margins
canal. | of gums; breath fœtid. Colic,
| constipation.
|
Nervous and muscular| Headache, delirium, stupor, amaurosis,
symptoms. | paralysis of the extensor muscles of the
| wrist, anæsthesia of the affected part.
| Fatty degeneration of the muscles.
|
Circumstances under | Certain trades, as painters, plumbers,
which it may occur. | type-founders, &c. Action of drinking
| water on lead. Hair-dyes, food in leaden
| utensils, &c.
|
Prophylaxis | Grinding lead colours in oil or water.
| Cleanliness in factories. Slate cisterns
| for water. Dilute sulphuric acid
| lemonade.
|
Medical treatment | Epsom salts, iodide of potassium, galvanic
| baths, &c.
--------------------+-------------------------------------------

COPPER

Metallic copper, like metallic lead, is not poisonous, but its oxides are; it should, therefore, not be swallowed, as it is rapidly acted on by the intestinal secretions and poisonous compounds formed. An alloy of copper is used for ornamenting ginger-bread, &c. All the salts of copper are poisonous. The most important are, however, the _sulphate_, _blue-stone_, or _blue vitriol_, and the _subacetate_ or _verdigris_.

Copper is eliminated to a slight extent by the urine. It has been found in the stomach, liver, and intestines eight months after its administration had been discontinued. It has also been detected more readily in the bronchial secretion than in the urine.

=Symptoms of Poisoning by Copper=

_Acute._--The primary action of the sulphate of copper in from five- to fifteen-grain doses is that of a quick emetic; in larger doses, a powerful irritant; but when absorbed, it appears to act chiefly on the brain and nervous system. Its irritant action is marked by nausea, vomiting, griping pain in the belly, which is greatly distended, and increased flow of saliva. The vomited matters are of a bluish or greenish colour, and the discharges from the bowels greenish and containing blood. The vomited matters become blue on the addition of ammonia. The above-mentioned symptoms usually follow immediately after the poison is swallowed, and rapidly increase in severity. After a time, the remote effects supervene, marked by headache, giddiness, laboured breathing, quick irregular pulse, coma or convulsions, paralysis, and death.

In poisoning by this substance, the convulsions are most violent, and wild incoherent delirium not infrequent.

The subacetate of copper or verdigris produces symptoms not unlike those just described. Jaundice and suppression of urine may result when either this or the sulphate is taken.

_Chronic._--Constant and troublesome irritation of the stomach and bowels; vomiting and purging, attended with considerable straining at stool; loss of appetite, loss of power, and general emaciation set in. The patient is subject to frequent trembling of the limbs, which may end in paralysis. The mouth is unpleasant, and a coppery, metallic taste is experienced. Cramps or colicky pains in the belly are not infrequently present. Jaundice is sometimes present. The vomited matters are greenish; but the practitioner must not be led away, and thus mistake the colour of the vomited matters which occur in some morbid states of the bile, for the result of poisoning by a salt of copper. A form of chronic poisoning affecting workers in this metal has been described by some French pathologists as “copper-colic.” A cachectic condition of the system, accompanied with one or more of the symptoms already detailed, marks this form of poisoning. _A purple_ line along the margins of the gums is present in some cases.

Copper poisoning may result from--

1. Its introduction into the system by using, for culinary purposes, copper vessels not properly tinned. An interesting account of poisoning from this source may be found in the second volume of the _Medical Observations and Inquiries by a Society of Physicians in London_, published 1764. The cases there recorded occurred on board ship, with most alarming symptoms.

2. By constant application of the metal to the surface of the body, necessitated by certain processes in its manufacture and in its application for industrial purposes. M. Michel Levy, however, says in his work, _Traité d‘Hygiène, Publique et Privée_, that workmen in copper may pass green-coloured urine and yet be as robust and as long-lived as other workmen.

3. The use of certain preparations of this metal as pigment.

4. The use of German silver--an alloy of copper, zinc, and nickel--may be rendered dangerous by the action of acid food upon the compound.

5. The use of a salt of copper to give a green fresh colour to certain tinned vegetables and fruits, peas, &c., now introduced into this country from France.

_Post-mortem Appearances._--The mucous membrane of the stomach is inflamed, the inflammation extending sometimes into the gullet. The intestines may be found perforated. The lining membrane of the whole alimentary canal presents a deep green colour, distinguished from that the result of a morbid condition of the bile by being turned blue on the addition of ammonia.

_Fatal Dose._--Nothing certain is known as to the exact quantity that may prove fatal, as the evidence of the poisonous action of copper is somewhat contradictory. It appears to be more dangerous in small doses than in large ones. Half an ounce of verdigris or subacetate has proved fatal to an adult.

_Fatal Period._--The shortest time on record is four hours.

_Treatment._--Induce vomiting, and assist the emetic action of the copper salts by the free use of warm water, milk, or any demulcent drink. The stomach tube may be used if vomiting does not occur. As an antidote, large quantities of albumen and iron filings have been given, of which the former appears to be most efficacious.

_Chemical Analysis._--The following are the liquid tests for copper in solution:--

1. Ammonia gives a bluish-white precipitate soluble in excess, forming a blue solution.

2. Sulphuretted hydrogen and ammonium sulphide give a chocolate-coloured precipitate.

3. Ferrocyanide of potassium gives a port-wine colour, or reddish-brown precipitate.

4. If a bright steel needle be introduced into an acid solution of copper, the metal is deposited on the needle.

5. If a piece of zinc bound with platinum wire be placed in a solution of a copper salt, the metal is deposited on the platinum; it is turned violet on exposure to the vapour from sulphuric acid mixed with potassium bromide.

=Detection of Copper in Organic Liquids=

_A._--The finely-divided tissue, or the contents of the stomach, diluted with water, are thrown on a filter, and the insoluble portion set aside for further treatment. (See _B._)

The filtrate and washings may now be concentrated, acidified with sulphuric acid, and a polished needle inserted in the liquid; and should no immediate deposition of metallic copper occur, it may be allowed to remain for several hours. The colour of the metallic deposit is highly characteristic of copper. As a corroborative proof, the concentrated liquid may be placed in a platinum capsule with some fragments of zinc, when the copper will be deposited on the platinum capsule at the parts in contact with the zinc; the liquid poured off, and the excess of zinc adhering to the platinum removed by dilute hydrochloric acid. The copper may now be dissolved off the platinum by nitric acid, the excess of acid driven off by heat, and the solution subjected to the wet tests given above.

_B._--The insoluble portion from _A_ is incinerated in a porcelain crucible. The ash thus obtained is digested in hydrochloric acid with the aid of heat, and evaporated nearly to dryness. The residue, dissolved in distilled water, may be tested as under ‘_A_.’

ZINC

The sulphate and the chloride of zinc are alone important. Poisoning by the chloride of zinc has been described (p. 265).

=Sulphate of Zinc=

White vitriol or white copperas.

_Symptoms._--The sulphate of zinc acts as a pure irritant. Violent vomiting, accompanied with pain in the abdomen, and purging, are the symptoms which first make their appearance. These may be followed by symptoms which betoken collapse, viz. coldness of the limbs, paleness of the face, irregular pulse, and fainting.

_Post-mortem Appearances._--Presence of inflammatory action.

_Fatal Dose._--Uncertain.

_Fatal Period._--Death has occurred in four hours.

_Chemical Analysis._--Distinguished from oxalic acid by remaining fixed when heated on platinum foil.

In Solution:

1. _Ammonia_ gives a white precipitate soluble in excess.

2. _Ferrocyanide of Potassium_, a white precipitate.

3. _Sulphuretted Hydrogen or Ammonium Sulphide_, a milky-white precipitate in a neutral pure solution.

4. _Nitrate of Baryta_, a white precipitate showing the presence of sulphuric acid.

5. _Caustic potash_ or _soda_, a white precipitate soluble in excess.

In Organic Mixtures pass sulphuretted hydrogen, collect the sulphuret, and decompose it with boiling hydrochloric acid, then test for zinc.

_Treatment._--Tea, coffee, milk, warm water, albumen, and in some cases enemata of gruel and other emollients.

IRON

The preparations of iron which are of importance are the sulphate and the muriate.

Sulphate of Iron

_Copperas_ or _Green Vitriol_--has been administered as a poison, but more frequently to procure abortion. An ounce has been taken with no other serious effect than the production of violent pain, purging, and vomiting. Constant application of this substance to the body has produced vomiting, pains in the belly and limbs. These symptoms disappear on treatment.

_Chemical Analysis._--(1) Hydrosulphuret of ammonia gives a black precipitate. (2) Ferrocyanide of potassium added to it, in solution, gives rise to a greenish-blue precipitate, becoming dark blue on exposure. (3) Chloride of barium will point to the nature of the acid present.

=Muriate of Iron=

Better known as the _Tincture of Sesquichloride of Iron_, or the _Tinctura Ferri Perchloridi_.--The tincture acts as a corrosive and irritant poison, death having followed in five weeks after an ounce and a half had been swallowed. It is sometimes used as an abortifacient. Recovery has, however, taken place after three ounces had been swallowed. The symptoms present in most cases observed were those of a corrosive and irritant.

_Chemical Analysis._--(1) The addition of nitrate of silver, causing a white precipitate insoluble in nitric acid, points to the presence of chlorine. (2) The peroxide of iron, indicated by the formation of Prussian blue on adding a solution of the ferrocyanide of potassium.

BISMUTH

The preparations of this metal act as irritant poisons, death having occurred from a dose of two drachms of the sub-nitrate. Dr. Trail (_Outlines of Medical Jurisprudence_, p. 116) mentions the ease of a patient of his who took _six drachms_ in three days in divided doses. The symptoms were vomiting, extreme pain in the abdomen and throat, a weak, feeble pulse, and much anxiety about the præcordia. Recovery took place. A case of severe vomiting during pregnancy, ending fatally, was mistaken for arsenic poisoning. The error arose from mistaking a greyish powder on the walls of the stomach for arsenic. It turned out on further inquiry that it was bismuth, given medicinally to prevent the vomiting. Bismuth carbonate mixed with gruel or bread and milk is given in large quantities for the purposes of radiography of the alimentary canal without any untoward effects.

POTASSIUM

=Nitrate of Potash=

This substance is well known as nitre, saltpetre, and sal prunella. In large doses it acts as an irritant, and cases are recorded in which it has been used to poison children. In one case, the presence of crystals of the salt in some of the dried vomited matter on the child‘s shoe, led to an explanation of the cause of death.

_Symptoms._--Those of a pure irritant, to which death must be referred, and not to any constitutional action of the drug. The nervous symptoms, which are sometimes very marked, are, as is well known, common to the action of many pure irritants. In some cases there is suppression of urine.

_Post-mortem Appearances._--Those produced by irritants generally.

_Chemical Analysis._--Separate the poison by dialysis, evaporate, and test the crystals as directed under nitric acid.

_Fatal Dose._--About an ounce.

_Fatal Period._--Two hours.

_Treatment._--The same as for other irritants; demulcent drinks. Promote vomiting.

=Sulphate of Potash=

_Sal Polychrist_, _Sal de Duobus_, or sulphate of potash, acts as an irritant poison, being largely used in France as an abortive. The symptoms and the _post-mortem_ appearances are much the same as those produced by the nitrate. A like treatment may also be adopted. In the detection of this substance, the nitrate of baryta will point to the acid present, and bichloride of platinum to the presence of potash.

=Chlorate of Potash=

This salt acts as a poison when taken in large doses, producing symptoms which might be mistaken for poisoning with arseniuretted hydrogen, or for such diseases as hæmoglobinuric fever.

_Symptoms._--These comprise pain in the stomach and bowels with vomiting, collapse and stupor, cyanosis, jaundice; diminution of the urine, which contains hæmoglobin, casts, and albumen. It is a question whether the jaundice is hæmatogenous or hepatogenous. Chlorate of potash destroys the red corpuscles, the hæmoglobin is dissolved out and is set free in the liquor sanguinis.

_Fatal Dose._--45-50 grains proved fatal to a child three years old. For an adult 390 grains to an ounce and a half.

_Fatal Period._--From five hours to several days.

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Text-book of forensic medicine and toxicologyChapter IV: Metallic Irritants (2)

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