[295] Tardieu, op. cit., Case 31.
[296] Diss. de Venefico Phosphoreo Acuto, Upsal, 1845.
[297] V. Bibra u. Geist, Die Krankheiten der Arbeiter in den Phosphorzundholz Fabriken, 1847, S. 59, &c.; Henle u. v. Pfeuffer’s Zeitschr. f. ration. Med., N. F., Bd. 7, Hft. 3, 1857.
[298] Étude Expérimentale sur quelques lésions de l’Empoisonnement aigu par le Phosphore (Thèse), Strasbourg, 1869.
§ 290. Antidote—Treatment.—After emptying the stomach by means of emetics or by the stomach-pump, oil of turpentine in full medicinal doses, say 2·5 c.c. (about 40 min.), frequently administered, seems to act as a true antidote, and a large percentage of cases treated early in this way recover.
§ 291. Poisonous Effects of Phosphine (phosphuretted hydrogen).—Experiments on pigeons, on rats, and other animals, and a few very rare cases among men, have shown that phosphine has an exciting action on the respiratory mucous membranes, and a secondary action on the nervous system. Eulenberg[299] exposed a pigeon to an atmosphere containing 1·68 per cent. of phosphine. There was immediate unrest; at the end of three minutes, quickened and laboured breathing (100 a minute); after seven minutes, the bird lay prostrate, with shivering of the body and wide open beak; after eight minutes, there was vomiting; after nine minutes, slow breathing (34 per minute); after twelve minutes, convulsive movements of the wings; and after thirteen minutes, general convulsions and death.
[299] Gewerbe Hygiene, p. 273.
The membranes of the brain were found strongly injected, and there were extravasations. In the mucous membrane of the crop there was also an extravasation. The lungs externally and throughout were of a dirty brown-red colour; the entire heart was filled with coagulated blood, which was weakly acid in reaction.
In a second experiment with another pigeon, there was no striking symptom save that of increased frequency of respiration and loss of appetite; at the end of four days it was found dead. There was much congestion of the cerebral veins and vessels, the mucous membrane of the trachea and bronchi were weakly injected, and the first showed a thin, plastic, diphtheritic-like exudation.
Dr. Henderson’s[300] researches on rats may also be noticed here. He found that an atmosphere consisting entirely of phosphine killed rats within ten minutes, an atmosphere with 1 per cent. in half an hour. The symptoms observed were almost exactly similar to those noticed in the first experiment on the pigeon quoted above, and the post-mortem appearances were not dissimilar. With smaller quantities of the gas, the first symptom was increased frequency of the respiration; then the animals showed signs of suffering intense irritation of the skin, scratching and biting at it incessantly; afterwards they became drowsy, and assumed a very peculiar attitude, sitting down on all-fours, with the back bent forward, and the nose pushed backwards between the forepaws, so as to bring the forehead against the floor of the cage. When in this position, the rat presented the appearance of a curled-up hedgehog. Phosphine, when injected into the rectum, is also fatal; the animals exhale some of the gas from the lungs, and the breath, therefore, reduces solutions of silver nitrate.[301]
[300] Journ. Anat. and Physiol., vol. xiii. p. 19.
[301] Dybskowsky, Med. Chem. Untersuchungen aus Hoppe-Seyler’s Labor. in Tübingen, p. 57.
Brenner[302] has recorded the case of a man twenty-eight years old, a pharmaceutist, who is supposed to have suffered from illness caused by repeated inhalations of minute quantities of phosphine. He was engaged for two and a half years in the preparation of hypophosphites; his illness commenced with spots before the eyes, and inability to fix the attention. His teeth became very brittle, and healthy as well as carious broke off from very slight causes. Finally, a weakness of the arms and limbs developed in the course of nine months into complete locomotor ataxy.
[302] St. Petersburg Med. Zeitschr., 4 Hft., 1865.
§ 292. Blood takes up far more phosphine than water. Dybskowsky found that putting the coefficient of solubility of phosphine in pure water at ·1122 at 15°, the coefficient for venous blood was ·13, and for arterial 26·73; hence the richer the blood is in oxygen the more phosphine is absorbed. It seems probable that the poisonous gas reacts on the oxyhæmoglobin of the blood, and phosphorous acid is formed. This is supported by the fact that a watery extract of such blood reduces silver nitrate, and has been also found feebly acid. The dark blood obtained from animals poisoned by phosphine, when examined spectroscopically, has been found to exhibit a band in the violet.
§ 293. Post-mortem Appearances.—There are a few perfectly well authenticated cases showing that phosphorus may cause death, and yet no lesion be discovered afterwards. Thus, Tardieu[303] cites a case in which a woman, aged 45, poisoned herself with phosphorus, and died suddenly the seventh day afterwards. Dr. Mascarel examined the viscera with the greatest care, but could discover absolutely no abnormal conditions; the only symptoms during life were vomiting, and afterwards a little indigestion. It may, however, be remarked that the microscope does not seem to have been employed, and that probably a close examination of the heart would have revealed some alteration of its ultimate structure. The case quoted, by Taylor[304] may also be mentioned, in which a child was caught in the act of sucking phosphorus matches, and died ten days afterwards in convulsions. None of the ordinary post-mortem signs of poisoning by phosphorus were met with, but the intestines were reddened throughout, and there were no less than ten invaginations; but the case is altogether a doubtful one, and no phosphorus may actually have been taken. It is very difficult to give in a limited space anything like a full picture of the different lesions found after death from phosphorus, for they vary according as to whether the death is speedy or prolonged, whether the phosphorus has been taken as a finely-divided solid, or in the form of vapour, &c. It may, however, be shortly said, that the most common changes are fatty infiltration of the liver and kidneys, fatty degeneration of the heart, enlargement of the liver, ecchymoses in the serous membranes, in the muscular, in the fatty, and in the mucous tissues. When death occurs before jaundice supervenes, there may be little in the aspect of the corpse to raise a suspicion of poison; but if intense jaundice has existed during life, the yellow staining of the skin, and it may be, spots of purpura, will suggest to the experienced pathologist the possibility of phosphorus poisoning. In the mouth and throat there will seldom be anything abnormal. In one or two cases of rapid death among infants, some traces of the matches which had been sucked were found clinging to the gums. The stomach may be healthy, but the most common appearance is a swelling of the mucous membrane and superficial erosions. Virchow,[305] who was the first to call attention to this peculiar grey swelling of the intestinal mucous membrane under the name of gastritis glandularis or gastradenitis, shows that it is due to a fatty degeneration of the epithelial cells, and that it is by no means peculiar to phosphorus poisoning. The swelling may be seen in properly-prepared sections to have its essential seat in the glands of the mucous membrane; the glands are enlarged, their openings filled with large cells, and each single cell is finely granular. Little centres of hæmorrhage, often microscopically small, are seen, and may be the centres of small inflammations; their usual situation is on the summit of the rugæ. Very similar changes are witnessed after death from septicæmia, pyæmia, diphtheria, and other diseases. The softening of the stomach, gangrene, and deep erosions, recorded by the earlier authors, have not been observed of late years, and probably were due to post-mortem changes, and not to processes during life. The same changes are to be seen in the intestines, and there are numerous extravasations in the peritoneum.
[303] L’Empoisonnement, p. 520.
[304] Poisons, 3rd ed., p. 276.
[305] Virchow’s Archiv. f. path. Anat., Bd. 31, Hft. 3, 399.
The liver shows of all the organs the most characteristic signs; a more or less advanced fatty infiltration of its structure takes place, which was first described as caused by phosphorus by Hauff in 1860.[306] It is the most constant pathological evidence both in man and animal, and seems to occur at a very early period, Munk and Leyden having found a fatty degeneration in the liver far advanced in twenty-four hours[307] after poisoning. In rats and mice poisoned with paste, I have found this evident to the naked eye twelve hours after the fatal dose. The liver is mostly large, but in a case[308] recorded in the Lancet, July 14, 1888, the liver was shrunken; it has a pale yellow (or sometimes an intense yellow) colour; on section the cut surface presents a mottled appearance; the serous envelopes, especially along the course of the vessels, exhibit extravasations of blood. The liver itself is more deficient in blood than in the normal condition, and the more bloodless it is, the greater the fatty infiltration.
[306] Hauff collected 12 cases, and found a fatty liver in 11.—Würtemb. Med. Corresp. Bl., 1860, No. 34.
[307] Die acute Phosphor-Vergiftung, Berlin, 1865.
[308] This case, from the similarity of the pathological appearances to those produced by yellow atrophy, deserves fuller notice:—“Frances A. Cowley, aged 20, on her own admission, took some rat paste on Tuesday, June 19th. Death ensued eleven days later. The initial symptoms were not very marked. Nausea and vomiting continued with moderate severity for a few days and then ceased. There ensued a feeling of depression. Towards the end insensibility, icterus, and somewhat profuse metrorrhagia supervened. At the necropsy the skin and conjunctivæ were observed of a bright yellow colour. There was no organic disease save of a recent nature, and entirely attributable to the action of the poison ingested. The stomach contained about three-quarters of a pint of dark claret-coloured fluid, consisting largely of blood derived from capillary hæmorrhage from the mucous membrane. There was no solution of continuity of the mucous membrane, which showed traces of recent irritation. The whole surface presented a yellow icteric tint, except the summits of some of the rugæ, which were of a bright pink colour. There was also faint wrinkling of the mucous membrane. The upper part of the small intestine was affected in much the same manner as the stomach. The large intestine contained a quantity of almost colourless fæces. The liver was shrunken, weighing only 26 ozs., and both on its outer and sectional surface exactly resembled the appearances produced by acute yellow atrophy, except that there were greater congestion and interstitial hæmorrhage in patches. The lobules of the liver were in many places unrecognisable; in others they stood in bold relief as brilliant canary-yellow patches, standing in strong contrast to the deep dark-red areas of congestion and extravasation. The gall-bladder contained about 2 drachms of thin greyish fluid, apparently all but devoid of bile. The urinary bladder was empty; the kidneys were enlarged; the cortex was very pale and bile-stained, of greater depth than natural, and of softer consistence. The spleen was not enlarged, nor was it in the least degree softened. In addition to the bleeding from the uterus noticed during life, there was capillary hæmorrhage into the right lung and pleura, into the pericardium, and, as already mentioned, into the stomach. The brain was healthy.”
In the Museum of the Royal College of Surgeons there is a preparation (No. 2737) of the section of a liver derived from a case of phosphorus poisoning.
A girl, aged 18, after two days’ illness, was admitted into Guy’s Hospital. She confessed to having eaten a piece of bread coated with phosphorus paste. She had great abdominal pain, and died on the seventh day after taking the phosphorus. A few hours before her death she was profoundly and suddenly collapsed. The liver weighed 66 ozs. The outlines of the hepatic lobules were very distinct, each central vein being surrounded by an opaque yellowish zone; when fresh the hue was more uniform, and the section was yellowish-white in colour. A microscopical examination of the hepatic cells showed them laden with fat globules, especially in the central parts of the liver.
The microscopic appearances are also characteristic. In a case of suicidal poisoning by phosphorus, in which death took place on the seventh day, the liver was very carefully examined by Dr. G. F. Goodart, who reported as follows:—
“Under a low power the structure of the liver is still readily recognisable, and in this the specimen differs from slides of three cases of acute yellow atrophy that I have in my possession. The hepatic cells are present in large numbers, and have their natural trabecular arrangement. The columns are abnormally separated by dilated blood or lymph-spaces, and the individual cells are cloudy and ill-defined. The portal channels are everywhere characterised by a crowd of small nuclei which stain with logwood deeply. The epithelium of the smaller ducts is cloudy, and blocks the tubes in many cases. Under a high power (one-fifth) it is seen that the hepatic cells are exceedingly ill-defined in outline, and full of granules and even drops of oil. But in many parts, even where the cells themselves are hazy, the nucleus is still fairly visible. It appears to me that, in opposition to what others have described, the nuclei of the cells have in great measure resisted the degenerative process. The change in the cells is uniform throughout each lobule, but some lobules are rather more affected than others. The blood-spaces between the cells are empty, and the liver appears to be very bloodless. The portal canals are uniformly studded with small round nuclei or cells, which are in part, and might be said in great part, due to increase of the connective tissue or to a cirrhotic process. But I am more disposed to favour the view that they are due to migration from the blood-vessels, because they are so uniform in size, and the hepatic cells and connective tissue in their neighbourhood are undergoing no changes in the way of growth whatever. I cannot detect any fatty changes in the vessels, but some of the smaller biliary ducts contain some cloudy albuminous material, and their nucleation is not distinct. No retained biliary pigment is visible.”[309]
[309] “A Recent Case of Suicide,” by Herbert J. Capon, M.D.—Lancet, March 18, 1882.
Oscar Wyss,[310] in the case of a woman twenty-three years old, who died on the fifth day after taking phosphorus, describes, in addition to the fatty appearance of the cells, a new formation of cells lying between the lobules and in part surrounding the gall-ducts and the branches of the portal vein and hepatic artery.
[310] Virchow’s Archiv. f. path. Anat., Bd. 33, Hft. 3, S. 432, 1865.
Salkowsky[311] found in animals, which he killed a few hours after administering to them toxic doses of phosphorus, notable hyperæmia of the throat, intestine, liver, and kidneys—both the latter organs being larger than usual. The liver cells were swollen, and the nuclei very evident, but they contained no fat, fatty drops being formed afterwards.
[311] Ibid., Bd. 34, Hft. 1 u. 2, S. 73, 1865.
§ 294. The kidneys exhibit alterations very similar and analogous to those of the liver. They are mostly enlarged, congested, and flabby, with extravasations under the capsule, and show microscopic changes essentially consisting in a fatty degeneration of the epithelium. In cases attended with hæmorrhage, the tubuli may be here and there filled with blood. The fatty epithelium is especially seen in the contorted tubes, and the walls of the vessels, both of the capsule and of the malpighian bodies, also undergo the same fatty change. In cases in which death has occurred rapidly, the kidneys have been found almost healthy, or a little congested only. The pancreas has also been found with its structure in part replaced by fatty elements.
Of great significance are also the fatty changes in the general muscular system, and more especially in the heart. The muscular fibres of the heart quickly lose their transverse striæ, which are replaced by drops of fat. Probably this change is the cause of the sudden death not unfrequently met with in phosphorus poisoning.
In the lungs, when the phosphorus is taken in substance, there is little “naked-eye” change, but Perls,[312] by manometric researches, has shown that the elasticity is always decreased. According to experiments on animals, when the vapour is breathed, the mucous membrane is red, congested, swollen, and has an acid reaction.
[312] Deutsch. Archiv f. klin. Med., vi. Hft. 1, S. 1, 1869.
In the nervous system no change has been remarked, save occasionally hæmorrhagic points and extravasations.
§ 295. Diagnostic Differences between Acute Yellow Atrophy of the Liver and Fatty Liver produced by Phosphorus.—O. Schultzen and O. L. Riess have collected and compared ten cases of fatty liver from phosphorus poisoning, and four cases of acute yellow atrophy of the liver, and, according to them, the chief points of distinction are as follows:—In phosphorus poisoning the liver is large, doughy, equally yellow, and with the acini well marked; while in acute yellow atrophy the liver is diminished in size, tough, leathery, and of a dirty yellow hue, the acini not being well mapped out. The “phosphorus” liver, again, presents the cells filled with large fat drops, or entirely replaced by them; but in the “atrophy” liver, the cells are replaced by a finely-nucleated detritus and through newly-formed cellular tissue. Yellow atrophy seems to be essentially an inflammation of the intralobular connective tissue, while in phosphorus poisoning the cells become gorged by an infiltration of fat, which presses upon the vessels and lessens the blood supply, and the liver, in consequence, may, after a time, waste.
There is also a clinical distinction during life, not only in the lessening bulk of the liver in yellow atrophy, in opposition to the increase of size in the large phosphorus liver, but also in the composition of the renal secretion. In yellow atrophy the urine contains so much leucine and tyrosin, that the simple addition of acetic acid causes at once a precipitate. Schultzen and Riess also found in the urine, in cases of yellow atrophy, oxymandelic acid (C8H8O4), but in cases of phosphorus poisoning a nitrogenised acid, fusing at 184° to 185°.
According to Maschka, grey-white, knotty, fæcal masses are found in the intestines in yellow atrophy, but never in cases of phosphorus poisoning. In the latter, it is more common to find a slight intestinal catarrh and fluid excreta.
§ 296. The Detection of Phosphorus.—The following are the chief methods in use for the separation and detection of phosphorus:[313]—
[313] It has been recommended to dissolve the phosphorus out from organic matters by carbon disulphide. On evaporation of the latter the phosphorus is recognised by its physical properties. Such a method is of but limited application, although it may sometimes be found useful. I have successfully employed it in the extraction of phosphorus from the crop of a fowl; but on this occasion it happened to be present in large quantity.
1. Mitscherlich’s Process.—The essential feature of this process is simply distillation of free phosphorus, and observation of its luminous properties as the vapour condenses in the condensing tube. The conditions necessary for success are—(1) that the apparatus should be in total darkness;[314] and (2) that there should be no substance present, such as alcohol or ammonia,[315] which, distilling over with the phosphorus-vapour, could destroy its luminosity. A convenient apparatus, and one certain to be in all laboratories, is an ordinary Florence flask, containing the liquid to be tested, fitted to a glass Liebig’s condenser, supported on an iron sand-bath (which may, or may not, have a thin layer of sand), and heated by a Fletcher’s low temperature burner. The distillate is received into a flask. This apparatus, if in darkness, works well; but should the observer wish to work in daylight, the condenser must be enclosed in a box perfectly impervious to light, and having a hole through which the luminosity of the tube may be seen, the head of the operator and the box being covered with a cloth. If there be a stream of water passing continuously through the condenser, a beautiful luminous ring of light appears in the upper part of the tube, where it remains fixed for some time. Should, however, the refrigeration be imperfect, the luminosity travels slowly down the tube into the receiver. In any case, the delicacy of the test is extraordinary.[316] If the organic liquid is alkaline, or even neutral, there will certainly be some evolution of ammonia, which will distil over before the phosphorus, and retard (or, if in sufficient quantity, destroy) the luminosity. In such a case it is well, as a precaution, to add enough sulphuric acid to fix the ammonia, omitting such addition if the liquid to be operated upon is acid.
[314] Any considerable amount of phosphorescence can, however, be observed in twilight.
[315] Many volatile substances destroy the luminous appearance of phosphorus vapour, e.g., chlorine, hydric sulphide, sulphur dioxide, carbon disulphide, ether, alcohol, petroleum, turpentine, creasote, and most essential oils. On the other hand, bromine, hydrochloric acid, camphor, and carbonate of ammonia do not seem to interfere much with the phosphorescence.
[316] Fresenius states that he and Neubauer, with 1 mgrm. of phosphorus in 200,000, recognised the light, which lasted for half an hour.—Zeitschr. f. anal. Chem., i. p. 336.
2. The Production of Phosphine (PH3).—Any method which produces phosphine (phosphuretted hydrogen), enabling that gas to be passed through nitrate of silver solution, may be used for the detection of phosphorus. Thus, Sonnenschein states that he has found phosphorus in extraordinary small amount, mixed with various substances, by heating with potash in a flask, and passing the phosphine into silver nitrate, separating the excess of silver, and recognising the phosphoric acid by the addition of molybdate of ammonia.[317]
[317] Sonnenschein, Handbuch der gerichtlichen Chemie, Berlin, 1869.
The usual way is, however, to produce phosphine by means of the action on free phosphorus of nascent hydrogen evolved on dissolving metallic zinc in dilute sulphuric acid. Phosphine is formed by the action of nascent hydrogen on solid phosphorus, phosphorous acid, and hypophosphorous acid; but no phosphine can be formed in this way by the action of hydrogen on phosphoric acid.
Since it may happen that no free phosphorus is present, but yet the first product (phosphorous acid) of its oxidation, the production of phosphine becomes a necessary test to make on failure of Mitscherlich’s test; if no result follows the proper application of the two processes, the probability is that phosphorus has not been taken.
Blondlot and Dusart evolve hydrogen from zinc and dilute sulphuric acid, and pass the gas into silver nitrate; if the gas is pure, there is of course no reduction; the liquid to be tested is then added to the hydrogen-generating liquid, and if phosphorous or hypophosphorous acids be present, a black precipitate of phosphor-silver will be produced. To prove that this black precipitate is neither that produced by SH2, nor by antimony nor arsenic, the precipitate is collected and placed in the apparatus to be presently described, and the spectroscopic appearances of the phosphine flame observed.
3. Tests Dependent on the Combustion of Phosphine (PH3).—A hydrogen flame, containing only a minute trace of phosphorus, or of the lower products of its oxidation, acquires a beautiful green tint, and possesses a characteristic spectrum. In order to obtain the latter in its best form, the amount of phosphine must not be too large, or the flame will become whitish and livid, and the bands lose their defined character, rendering the spectrum continuous. Again, the orifice of the tube whence the gas escapes must not be too small; and the best result is obtained when the flame is cooled.
M. Salet has proposed two excellent methods for the observation of phosphine by the spectroscope:—
(1) He projects the phosphorus-flame on a plane vertical surface, maintained constantly cold by means of a thin layer of running water; the green colour is especially produced in the neighbourhood of the cool surface.
(2) At the level of the base of the flame, there is an annular space, through which a stream of cold air is continually blown upwards. Thus cooled, the light is very pronounced, and the band δ, which is almost invisible in the ordinary method of examination, is plainly seen.[318]
[318] Consult Spectres Lumineux, par M. Lecoq de Boisbaudran, Paris, 1874. See also Christofle and Beilstrom’s “Abhandlung,” in Fresenius’ Zeitschr. f. anal. Chem., B. 2, p. 465, and B. 3, p. 147.
An apparatus (devised by Blondlot, and improved by Fresenius) for the production of the phosphine flame in medico-legal research, is represented in the following diagram:—
Several of the details of this apparatus may be modified at the convenience of the operator. A is a vessel containing sulphuric acid; B is partly filled with granulated zinc, and hydrogen may be developed at pleasure; c contains a solution of nitrate of silver; d is a tube at which the gas can be lit; e, a flask containing the fluid to be tested, and provided with a tube f, at which also the gas issuing can be ignited. The orifice should be provided with a platinum nozzle. When the hydrogen has displaced the air, both tubes are lit, and the two flames, being side by side, can be compared. Should any phosphorus come over from the zinc (a possibility which the interposed silver nitrate ought to guard against), it is detected; the last flask is now gently warmed, and if the flame is green, or, indeed, in any case, it should be examined by the spectroscope.[319]
[319] F. Selmi has proposed the simple dipping of a platinum loop into a liquid containing phosphoric acid, and then inserting it into the tip of a hydrogen flame.
§ 297. The spectrum, when fully developed, shows one band in the orange and yellow between C and D, but very close to D, and several bands in the green. But the bands δ, γ, α, and β are the most characteristic. The band δ has its centre about the wave-length 599·4; it is easily distinguished when the slit of the spectroscope is a little wide, but may be invisible if the slit is too narrow. It is best seen by M. Salet’s second process, and, when cooled by a brisk current of air, it broadens, and may extend closer to D. The band γ has a somewhat decided border towards E, while it is nebulous towards D, and it is, therefore, very difficult to say where it begins or where it ends; its centre may, however, be put at very near 109 of Boisbaudran’s scale, corresponding to W. L. 560·5, if the flame is free. This band is more distinct than β, but with a strong current of air the reverse is the case. The middle of the important band α is nearly marked by Fraunhofer’s line E. Boisbaudran gives it as coinciding with 122 of his scale W. L. 526·3. In ordinary conditions (that is, with a free uncooled flame) this is the brightest and most marked of all the bands. The approximate middle of the band β is W. L. 510·6 (Boisbaudran’s scale 129·00).
Lipowitz’s Sulphur Test.—Sulphur has the peculiar property of condensing phosphorus on its surface, and of this Lipowitz proposed to take advantage. Pieces of sulphur are digested some time with the liquid under research, subsequently removed, and slightly dried. When examined in the dark, should phosphorus be present, they gleam strongly if rubbed with the finger, and develop a phosphorus odour. The test is wanting in delicacy, nor can it well be made quantitative; it has, however, an advantage in certain cases, e.g., the detection of phosphorus in an alcoholic liquid.
Scherer’s test, as modified by Hager,[320] is a very delicate and almost decisive test. The substances to be examined are placed in a flask with a little lead acetate (to prevent the possibility of any hydric sulphide being evolved), some ether added, and a strip of filter-paper soaked in a solution of silver nitrate is then suspended in the flask; this is conveniently done by making a slit in the bottom of the cork, and in the slit securing the paper. The closed flask is placed in the dark, and if phosphorus is present, in a few minutes there is a black stain. It may be objected that arsine will cause a similar staining, but then arsine could hardly be developed under the circumstances given. It is scarcely necessary to observe that the paper must be wet.
[320] Pharm. Central-halle, 20, 353.
§ 298. Chemical Examination of the Urine.—It may be desirable, in any case of suspected phosphorus poisoning, to examine the renal secretion for leucin and tyrosin, &c. Leucin may be found as a deposit in the urine. Its general appearance is that of little oval or round discs, looking like drops of fat. It can be recognised by taking up one or more of these little bodies and placing them in the author’s subliming cell (see § 314). By careful heating it will sublime wholly on to the upper cover. On now adding a little nitric acid to the sublimed leucin, and drying, and then to the dried residue adding a droplet of a solution of sodium hydrate, leucin forms an oily drop. Tyrosin also may occur as a sediment of little heaps of fine needles. The best test for tyrosin is to dissolve in hot water, and then add a drop of a solution of mercuric nitrate and mercurous nitrate, when a rose colour is at once developed, if the tyrosin is in very minute quantity; but if in more than traces, there is a distinct crimson precipitate. To separate leucin and tyrosin from the urine, the best process is as follows:—The urine is filtered from any deposit, evaporated to a thin syrup, and decanted from the second deposit that forms. The two deposits are mixed together and treated with dilute ammonia, which will dissolve out any tyrosin and leave it in needles, if the ammonia is spontaneously evaporated on a watch-glass. The urine is then diluted and treated with neutral and basic acetates of lead, filtered, and the lead thrown out of the filtrate by hydric sulphide. The filtrate is evaporated to a syrup, and it then deposits leucin mixed with some tyrosin. If, however, the syrup refuses to crystallise, it is treated with cold absolute alcohol, and filtered, the residue is then boiled up with spirit of wine, which extracts leucin, and deposits it on cooling in a crystalline form. To obtain oxymandelic acid, the mother liquor, from which leucin and tyrosin have been extracted, is precipitated with absolute alcohol, filtered, and then the alcoholic solution evaporated to a syrup. This syrup is acidified by sulphuric acid, and extracted with ether; the ether is filtered off and evaporated to dryness; the dry residue will be in the form of oily drops and crystals. The crystals are collected, dissolved in water, and the solution precipitated by lead acetate to remove colouring-matters; after filtration it is finally precipitated by basic acetate. On decomposition of the basic acetate, by suspending in water and saturating with hydric sulphide, the ultimate filtrate on evaporation deposits colourless, flexible needles of oxymandelic acid. The nitrogenised acid which Schultzen and Riess obtained from urine in a case of phosphorus poisoning, was found in an alcohol and ether extract—warts of rhombic scales separating out of the syrupy residue. These scales gave no precipitate with basic acetate, but formed a compound with silver nitrate. The silver compound was in the form of shining white needles, and contained 33·9 per cent. of silver; the acid was decomposed by heat, and with lime yielded aniline. Its melting-point is given at from 184° to 185°. The occurrence of some volatile substance in phosphorus urine, which blackens nitrate of silver, and which is probably phosphine, was first noticed by Selmi.[321] Pesci and Stroppa have confirmed Selmi’s researches. It is even given off in the cold.
[321] Giornale Internaz. della Scienza Med., 1879, Nro. 5, p. 645.
§ 299. The quantitative estimation of phosphorus is best carried out by oxidising it into phosphoric acid, and estimating as ammon. magnesian phosphate. To effect this, the substances are distilled in an atmosphere of CO2 into a flask with water, to which a tube containing silver nitrate is attached; the latter retains all phosphine, the former solid phosphorus. If necessary, the distillate may be again distilled into AgNO3; and in any case the contents of the U-tube and flask are mixed, oxidised with nitromuriatic acid, filtered from silver chloride, and the phosphoric acid determined in the usual way.
In the case of a child poisoned by lucifer matches, Sonnenschein estimated the free phosphorus in the following way:—The contents of the stomach were diluted with water, a measured part filtered, and the phosphoric acid estimated. The other portion was then oxidised by HCl and potassic chlorate, and the phosphoric acid estimated—the difference being calculated as free phosphorus.
§ 300. How long can Phosphorus be recognised after Death?—One of the most important matters for consideration is the time after death in which free phosphorus, or free phosphoric acids, can be detected. Any phosphorus changed into ammon. mag. phosphate, or into any other salt, is for medico-legal purposes entirely lost, since the expert can only take cognisance of the substance either in a free state, as phosphine, or as a free acid.
The question, again, may be asked in court—Does the decomposition of animal substances rich in phosphorus develop phosphine? The answer to this is, that no such reaction has been observed.
A case is related[322] in which phosphorus was recognised, although the body had been buried for several weeks and then exhumed.
[322] Pharm. Zeitsch. f. Russl., Jahrg. 2, p. 87.
The expert of pharmacy of the Provincial Government Board of Breslau has also made some experiments in this direction, which are worthy of note:—Four guinea-pigs were poisoned, each by 0·023 grm. of phosphorus; they died in a few hours, and were buried in sandy-loam soil, 0·5 metre deep. Exhumation of the first took place four weeks after. The putrefying organs—heart, liver, spleen, stomach, and all the intestines—tested by Mitscherlich’s method of distillation, showed characteristic phosphorescence for nearly one hour.
The second animal was exhumed after eight weeks in a highly putrescent state. Its entrails, on distillation, showed the phosphorescent appearance for thirty-five minutes.
The third animal was taken from the earth after twelve weeks, but no free phosphorus could be detected, although there was evidence of the lower form of oxidation (PO3) by Blondlot’s method.
The fourth animal was exhumed after fifteen weeks, but neither free phosphorus nor PO3 could be detected.[323]