Document V3djr3nVqyo5DQe05eem3VQN8

EXPERIMENTAL STUDIES ear TBTRAETHTL LEAD POISONING BT ROBERT A. KEHDB, H.D. EICHBERG LABORATORY OP PHYSIOLOGY, UNIVERSITY OP CINCINNATI, CINCINNATI* OHIO. ASSISTED BY THE STAFF OP THE RESEARCH IABORATCRY OP THE ETHYL GASOLINE CORPORATION DAYTON,OHIO KE 0017786 THE TOXIC ITT OF TETRAETHYL LEAD. The toxicity of tetraethyl lead for rabbits has been de termined for the various methods of administration, and it has been compared -with the toxicity of certain inorganic salts of lead. In the case of both tetraethyl lead and the inorganic salts of lead a sufficient number of animals have been studied to make possible a proper allowance for individual variation* If oily the lethal amount for a single administration be considered, little individual variation is seen. However, if the toxicity be considered on the basis of numerous repeated administrations, a considerable variation is found. The fatal dosages of tetraethyl lead administered in one dose to rabbits by various means are substantially as follows: Intravenously, 0.014 co. per kilo body weight, approximately 0.014 grams lead per kilo; outaneously 0.7 oc. per kilo body weight, or about 0.7 grams lead per kilo; by oral administration 0.11 c.o. per kilo body wei^it or about 0.11 grams lead per kilo; the quantity taken into the body of the animal by inhalation is difficult to cal culate for a variety of reasons, but the concentration of tetraethyl lead in terms of lead in the air breathed by the animal which will kill in about three days of six-hour daily exposure is approximately 0.182 mg. per liter of air. HE 0017787 - 2. In all of these methods death of the animal takes place in from six to seventy-two hours. The fatal dosages of salts of lead such as the ehloride and nitrate are not widely variant from the above figures. When lead chloride is administered intravenously, a var iety of things may occur, dependent upon the salt employed, the speed of administration and the concentration of the solution. The animal maydie at onoe; he may develop a thrombosis at the site of the injection, or he may develop a general systemic poisoning. The lethal dosage is calculated on the basis of the last situation, to be about 0.015 grams of lead per kilo. When administered orally, approximately 0.037 grams of lead per kilo are required to produce death from one dose. In the case of lead nitrate approximately O.OH grams of lead per kilo injected intravenously brings about death within twenty-four hours. The cutaneous application of inorganic salts of lead results neither in death nor illness of the animals. Comparison of the toxioity of tetraethyl lead with that of the inorganic salts of lead, shows that in general these are of the same order of magnitude. An exception of sufficient magnitude to be well out side the limit of chanoe variation is seen, however, when one compares the poisonous character of lead salts taken by mouth with that of tetraethyl lead taken in the same way. In this case the salts of lead are seen to KE 0017788 - 3. 'be about three times as toxic as tetraethyl lead* This is probably due to the greater ease of absorption of lead salts in the alimentary tract* On the other hand* lead salts are not absorbed in lethal doses from shin* whereas death may readily he produced by the application of tetraethyl lead to the shin. The general conclusion which seems to be obvious from the above data* Is that tetraethyl lead owes its toxicity to the lead and not to any other part of the compound, tetraethyl lead, is not peculiarly toxic as compared with other heavy metal compounds, but that its principal danger resides in the fact that it is readily absorbed through the shin* as well as being capable of inhalation because of its volatility* TThen tetraethyl lead is administered in smaller repeated doses* the outcome is dependent upon the size of the dose and the time interval between doses* In a series of rabbits treated with 0*1 c.c. at intervals of three days symptoms began to appear in most esjea after six to eight treatments. {The only symptom was a slight loss of weigit.) The total quantity applied before the death of these animals averaged about twice the amount of a single lethal dose. It will be seen from the con sideration of later experiments that the lethal amount is dependent not so much on the total quantity of lead which the animal is led to absorb, but rather upon the concentration aatively mobilized (in the blood stream prob ably) at a particular time* KE 0017789 t ie ACCTnraLmasr q p l ead nr ex per imeh t al AEIMALS TREATED WITH TETRAETHYL LEAD When rabbits are treated at regular intervals with. sablethal doses of tetraethyl lead, there is an accumulation of lead in the body of the antml. The rate of accumulation depends upon the size of the dose administered and the time interval between injections. The quantity of lead found in the animal varies, however, not only with the quantity administered, but also with the time which has elapsed between administration of the last dose and the time of analysis of the animal. That is, the rate of secretion is of such an order of magnitude as to make striking differences in the quantity of lead found In animals treated in an identical manner. With the acouanalation of lead in the animal there is no evidence of a chronic poisoning, with the single exception of a slight loss of weight. If the animal becomes ill, his symptoms are acute and death results. In the table below my be seen observations and analyt ical data collected on a series of nine rabbits, treated at intervals of three days with o.l c.o. of pure tetraethyl lead, applied to the skin of the abdomen. 00177S0 N22274.01 -2 Babbit Bo. 31 Weight 5-3/8 # Ho* 34 HO* 35 s-a/s # 6f Ho* 36 HO. 37 5-3/4 # 6-3/4 # Ho. 39 4-7/8 # HO. 40 Ho. 42 4-1/2 # 4-5/8 # HO. 60 3-1/2 # Husiber of Treatments 16 13 15 17 7 14 14 11 10 Time of Appear ance of loss of weight. Result Lead Determ ination in milligrams 7th treatment hied 23 days after last treatment. 15.3 Ho loss of weight Same 9.78 8th treatment hied day after 15th treatment 96.0 14th " Survived hied after 7th treatment 90. 7th " hied 29 days after last treatment 7.10 7th " Survived 9th ' hied after 11th treatment 51.25 7th " jams. Survived That the large variations in the quantity of lead found in these animals may be, and probably are due to the secretion of lead by the animal is indicated by the data collected on the rate of secretion of lead from the body of certain of these animals. The animals in this ease were installed in the ordinary metabolism cage with a lead free floor* The urine and faeces were collected over periods of several days and analysis was made* The cages were first tested as to their lead--free character by using leadfree animals as controls* The diets of the animals were unchanged during the period of collection* 0017791 Babbit 2 controls Ho* 31* Ho. 36 Bo. 39 Period of Collection 7 days 7 7" 7* Quantity of Lead in MillieramB mi 5.89 4.00 2.03 notes This animal died Beoen&er 21* Hia entire tody contained 15*3 mg. lead. Some idea can be obtained of the quantity of lead In the body of this animal at a time 'when he mas excreting almost 1 mg. per day. This fairly rapid rate of excretion raises the question as to whether in the decomposition of the tetraethyl lead molecule a compound of lead may not be formed which is more readily excreted than the ordinary compounds of lead. This question is presented the more strongly when the rate of excretion of lead in men poisoned by tetraethyl lead is studied. 0017792 IS22274 THE DISIFRIBOTIQN OF LEAD IS POISONED ANIMALS A number of animals known to contain considerable quantities of lead at the time of death were analysed after the separation of their tissues. The data below indicates the manner of poisoning of the animal* together with the lead content of various tissues* p4abbit Ho. 32 - Exposed for 72 days to vapor of pb (Et)4 in air at the rate of 100 ce* Pb{EtJ4 vapor to 5 liters of air* tissue Bones Skin Liver and Kidneys Central Nervous System Fetuses in Etero Other tissue Weight 225 grams 300 55 " 13 126 " 2045 * Lead in Milligrams 9*15 3*16 3.70 Hil 0*26 8.75 Hotei One liter of saturated vapor of FbfEt)^ at 25* G. contains 0.00456 grama PB* 0017793 - 2. Babbit Ho* 31 - Treated every three days with 0*1 cc. Pb{EtU, sixteen treatments* Died twenty-three days after last treatment* Tissue Weight Lead in Milligrams Bones Skin 325 grams 260 tt 8*04 4.49 liver and Kidneys 105 tt 1*15 Central Nervous System Other tissue 13.5 tt 1590 It Lost in analysis 2.02 O O Urine in Bladder 50 0*14 Babbit Ho* 16 - Exposed for ninety-dight days to vapor of Pb(Et)^ in air at rate cf 5 ce* of Pb(Bt)4 to 5 liters of air, and thou for three days to 200 cc* vapor in five liters of air* Pied* Tissue Weight lead in Milligrams Bones 520 grams 2*22 liver 82 3.75 Central Nervous System 18 0*13 Bemainder {without shin) 2160 26.00 KE 0017794 SHE EFFECT OF SESRAETHTL LEAD OK AEB1A1S When toxic amount8 of tetraethyl lead are administered to rabbits, the first symptoms seen are lac& of appetite mid loss of weight# A sluggishness end lassitude are apparent* and the animal sits with drooped eara and arched hack* As the symptoms increase in severity, he hecoses nervous* saving about in the cage from place to place* stopping from time to time to sinh into a drowsy state* The temperature does not ordinarily vary sore than is normal in these animals# hut respiration quietens at first and then* with in creasing severity of symptoms, decreases* If sufficient tine Inter venes before death, a watery diarrhoea develops* Convulsions usually occur as a terminal sign* and tbs animal dies with bulging* congested eyes and paralysed respiration, with the heart continuing for some time afterward When illness results from inhalation there is an irritation, with some weeping of the mucous ses&ranes* The upper respiratory tract may become red and in very severe cases even haemor rhagic* When the application is made on the abdominal wall* there is an almost immediate increase in the peristaltic activity of the intes tines* Sapid peristalsis nay be easily observed under the abdominal wall* During the course of thsir illness, Mother acute or prolonged, no characteristic objective signs develop* There is no typical alter ation of the blood picture* {Stippling and polychromatophili^ are found almost uniformly in normal rabbits, so that no minute Changes 0017795 N22274.03 wold be demonstrable*) Only a slight anemia baa appeared in any exper imental animal thus far* Post-mortem examination of poisoned animals discloses certain characteristic, though not definitely differentiating, changes* These are confined almost wholly to the alimentary tract and the central nervous system* Thera 1c a considerable amount of capillary dilitatlon of the viscera generally and the heart is nssally dilated and flabby, but the pronounced findings are seen in an acute intestinal irritation and desqua mation and an acute edema of the brain* The Intestinal change is confined almost wholly to the small intestine and is most pronounced in the duodenum* Here the intestine is filled with a stiofcy mucoid fluid which may be, but usually is not, blood tinged* It is characteristically yellowish end glairy, and often coagulates spontaneously on standing for a time* The mucosa in this region is thin and almost fluid in character. Bo actual ulceration is found, and there are seldom any definite baesorrhagie areas* The brain is either dry and swollen and very friable, or alee it is very wet with a large amount of free fluid under the dura, especially at the base* Microscopic findings are very meager* Bo characteristic change has been found* The study of microscopic pathology has not bean completed* Among tbs effects on experimental animals, which should be noted In passing is the Influence of lead poisoning on pregnancy and the procreative functions in general* 1 number of pregnant female rabbits have given birth to premature litters* In several cases abortion or miscarriage has resulted shortly after the administration of the poison. Hcwevor, the loss of ability to reproduce has not occurred in the ease of either male or female rabbits* animals which have been severely poisoned have both fertilised and become impregnated ana have brought forth normal young after only brief periods of recover*......... ............................................................. ________ _ _ E 0017796 OH THE ABSOBPTIOH OF TETRAETHYL LEAD THROUGH THE SKIS, AJJD SHE ABSORPTIOH OF TETRAETHYL LEAD OUT OF GASOLXHE. In tbs former experiments, in which tbe toxicity of tetraethyl lead as absorbed through tbs skin, was determined, there was in almost egery case a possibility that tbe animal bad obtained a portion of tbe lead by inhalation and ingestion. It was determined, therefore, to carry out some experiments to control this factor, and to establish, beyond any doubt, the facts in the matter. Accordingly, animals were selected of approximately the same size and age and were exposed to a definite concen tration of tetraethyl lead in gasoline for a definite period of time, after which the tetraethyl lead was carefully removed by means of kerosene, and subsequently soap and water. During the period of exposure the animal was tied down, and ventilation was maintained in such a way as to prevent apprec iable inhalation of the gasoline-tetraethyl lead vapor. A second purpose in these experiments was to discover whether tetraethyl lead could be absorbed through the skin out of gasoline. The practical importance of the latter question lay in the fact that the exposure to tetraethyl lead, on the part of distributors end eenavsaers, would have to do with this solution in eontaet with the skin. Since in almost every case such gasoline would be wiped off or washed off before evaporation, the relative rates of absorption of gaso line and tetraethyl lead, and the partition occurring between the gasoline and the skin, as solvents for tetraethyl lead, would determine, largely the magnitude of any hazard arising from exposure to gasoline containing tetra ethyl lead. 0 017 7 y 7 N22274.04 -2 The following experiments show that tetraetlyl lead may be absorbed through tbe skin of experimental animals, in quantities suffic ient to produce death, when the factors of inhalation and ingestion are adequately controlled* Further, they stow, that thetraethyl lead may be absorbed out of gasoline, though there Is no indication of any select ive absorption* They indicate, however, that the quantity of tetraethyl lead vftiich may be absorbed out of a solution of tetraethyl lead in gaso line comparable to commercial "Bthyl Gasoline", is very minute. faroeriraants* 1* Three rabbits of approximately the same weight (about 2 kilo) were exposed for half an hour each, on three consecutive days, to a one to ten dilution of tetraethyl lead in gasoline* Bach animal was care fully tied down on a comfortable board, as much as possible of the hair was clipped from a fore leg without any abrasion, and the leg was gently but firmly hold in a test tube Of the solution, down to the elbow Joint. Care was taken not to interfere with the circulation. The quantity of solution to which the leg was exposed was ajproximately 35 oc* The ex posure was carried out in a hood where the air was being changed rapidly* At the end of the exposure the leg was bathed in kerosene repeatedly, wiped dry, end then treated with cold cream, for the purpose of counter acting the harmful effect of the gasoline on the skin* At the end of three such treatments, the animals developed par alysis of the hind legs, and on the next day they died* Control animals, two in number, of the same wfeight, treated In exactly the same manner, KE 0017798 . 8. except that the gasoline contained no tetraethyl lead* showed no In dication of injury heyond sene degree of irritation of the sldn* One of the animals was ashed and an analysis for lead was made* The entire carcass contained 36.46 milligrams of lead. It is well to point out that this animal had been exposed for 1--1/2 hours to 105 oc. of a solution containing approximately 10 grams of lead. Approximately 0.35 of X% was absorbed. 2. Ten rabbits wore selected and were treated in the same manner, three being used as controls, and seven being exposed for half an hour at a time to a dilution of one part of tetraethyl lead in one hundred parts of gasoline. For the first seven days the treatment was carried out daily. After this the exposureawere made twice weekly. This was done because of the skin irritation which resulted from the daily treat ment. It was found that the skin could be kept intact by increasing the interval between exposures, provided the cream in the interval. be treated wi th cold The following table shows the results of such treatment* _. Ho.. Animal 89 control 93 H 98 (t 90 1*100 91 1*100 92 1*100 Ho. Treatments 28 27 27 7 29 29 height Before After 2-3/4 5-1/8 4--1/4 5-1/8 3-1/4 3-3/4 4--1/4 4-3/8 3-3/4 4-3/4 4-3/4 5-1/8 Hesult Survived ft M Killed for analysis* Survived tt K.E:.a0.l7799 Ho. Animal 94 ItlOO 95 lilOO 96 1:100 97 1:100 Ho. Treatments 16 27 25 22 Weight Before After 4-1/4 4-1/2 4-1/4 3-1/2 5-1/4 4 6-1/2 4-1/2 - 4. Hesuit Pied suddenly with out previous illness** 111 after 10th treat ment. Recovered. Survived. Faralysis and death*** * Lead content of carcass of 90 3*81 mg. * Lead content of carcass of 94 7.50 rag. *** Ho analysis was made of carcass of 97. The above data show that there is an accumulation of lead in rabbits treated with gasoline containing a sufficient quantity of tetraetlyl lead, and that the animals may be poisoned by a concentration of one part tetraethyl lead to one hundred parts of gasoline. It is of some importance to see that animals treated with a concentration of one part of tetraethyl lead to one hundred parts of gasoline absorbed approximately one-thirtieth as much as animals exposed under identical conditions to ten times that concentration, l.e. one to ten. 0017300 OH THE TOXICITY OF ETHYL GASOLIUE. The question of the hazard existing in the handling of Ethyl Gasoline hinges upon two considerations* {a} whether the quantity of tetraethyl lead volatilizing out of gasoline at the existing concentration f 1.1300 approximately) is sufficient to causa appreciable ab sorption of lead; lb) whether shin absorption of tetraethyl lead in gasoline can occur to an extent sufficient to cause poisoning. Hotet Gram the Besearch Laboratories of the Ethyl Gaso line Corporation and the Eichberg Laboratory of Physiology, University of Cincinnati, Cincinnati, Ohio. N22274.05 Both of these problems were investigated by exposing animals to conditions as nearly like the normal conditions of human exposure as could be devised* For this purpose guinea pigs and monkeys were selected; guinea pigs, because of their susceptibility to lead poisoning* and monkeys because of their similarity to the human being* The guinea pigs were divided into four gxovpe, kept separate, but fed and cared for in exactly the same manner. Eleven pigs, four females and the remainder males, were treated on the skin surface of the helly, after clipping off the hair, with 1 cc* of ethyUsed gasoline* Eleven, all females, were set aside as untreated controls* Eleven, five of which were females, were treated with 0*2 cc. of ethylized gasoline. Three, one male and two females, were treated with 1 cc. of ordinary gaso line. The gasoline tmed was a good grade of high test eonraercial gasoline* The ethylized gasoline was prepared by first making a mixture of pure tetraethyl lead and ethylene dibromide in the proportion of three parts of lead to two parts of dibromide* This mixture was kept in a tightly sealed brown bottle to prevent decomposition, and was mixed in gasoline in quantities of 0*25 to* to 200 cc* of gasoline, as needed* This corresponds to the most concentrated mixture of tetraethyl lead in gasoline, known as a 3 E. mix*, representing approximately one part by volume of tetraethyl lead per thirteen hundred parts of gasoline* The monkeys, four in number, of the Rhesus type, were all cared for in the same manner* Two were used for controls, aid two were treated daily with 2 oo. of Ethyl gasoline, prepared in the above manner. I The hair was dipped from aa area on the back, as large as the palm of the hand and the gasoline mixture was dropped on out of a pipette* One of the monkeys to be used as a control died within a few days after his arrival, having contracted pneumonia in transit* The other control es caped from his cage and died of exposure before he could be captured* The two being treated as above were continued without any controls for compari son* The following paragraphs indicate the course of the experi ments carried out upon these animals* GXJI5M PIGS. Pen Ho* 1* 4 females T males treatments twice weekly* Treated with 1 cc. Ethyl Gasoline* Humber of treatments 40* In the period from Hovember 25th, to the present there hare been no natural deaths among these animals* Three were killed for analysis on March 3rd, and one was killed for analysis on March 31* The females have given birth to six young which have survived, two of which were born May 14th* There have been two litters of young bom dead* These occurred In January and February, during periods of inclement weather, in which all of the animals suffered somewhat Two pigs were selected, because of distinctive markings, for observation of blood conditions* The initial observations on the two were as followst (a) Hb (Pare Mathod) 90, Bed Count, 6,160,000 (b) Hb. 110, * * 5,200,000 0 017 3 0 3 _ ---------------------- -- - - __ _ Observations made on fifey 17th, wore as follows* {a} Hb. 90 Bed Count, 5,754,000 (b) Hb. 105, H 5,230,000 Blood smears show no qopredable change now as compared with the original observations* Guinea pig blood trader normal conditions shows a variable amount of polychromatophilia, and an occasional stippled eell may be found in the blood of a normal animal* In the two pigs above no stippling has ever been seen* Bluish or basophilic staining erythrocytes may be seen in almost every field* Shore has been no noticeable increase in the number of these* SMM Of the 7 pigs remining in this group two sales do not appear to be in good condition at present. They have been fighting almost constantly lately, and have inflicted many deep wounds troon each other, some of which are infeeted and suppurating* It has been thought advisable to segregate these animals and continue the experiment to see if healing of wounds will bring about recovery. The two females remain ing look healthy and sleek, except for the irritation of the skin of the belly. Ben Be* 2* 11 Females* Not treated. Male from Pen 4 introduced* There have been no natural deaths among these animals* Three were killed for analysis, March 3rd, and one was killed for analysis March 31st* Forty young have been bora alive, of which three have died within a few days of the day of their birth. Three females have given birth prematurely to young, one of these on May 13th. Two pigs 'were selected for their distinctive markings* and "blood examinations were made as in the case of group Ho* 1* So variation was seen in the "blood picture, and no variation as conpared with those in Pea jro. 1 was seen, except that in one pig an occasional stippled erythrocyte was found. These animals are in good condition, and present no demons trable deviation from the normal. Pen, Ho. 3, 6 Females 5 Bales Treatments twice weekly. Treated with 0.2 cc. Ethyl Gasoline. H2mber of treatments 40. Since November 25th, the beginning of the experiment, there have been no deaths among these animals as a result of illness. Three werekilled for analysis on March 3rd. Twenty-four young ones have been born, of sfoich nineteen are now alive. The others died within a day or two of their birth. There have been three litters bom dead. Hone of these occurred since April 1st. The blood findings in these animals are no mom significant than those in the other groups of pigs. So variation from the normal has been found in spite of repeated examinations. The animals are all healthy. pen Ho. 4. 1 Male 2 Females Treatments twice weekly. Treated with 1 co. Gasoline. Humber of treatments 40 There have been no deaths in this group. Two litters of young have been bora, six young in all, of which one was dead at birth. jrO blood examinations have been made on the pigs in this pen 0017 3 0 5 since the first eaaE&nation. They were used largely as controls on the influence of the gasoline alone on the sfidtn. Ko variation is seen either in the condition of their skin, or their general appearance as compared to treated animals. An unfortunate and unforeseen variable ms found in the conduct of these experiments, when a group of treated and control animals were killed for analysis on March 3rd. The table below shows the lead content of the carcasses of these animals. It will be seen that the quantity of lead is practically the same in all animals, treated and con trol alike. This was not due to any mistakes in handling or treating the animals, nor ms there the remotest chance of incorrect selection of animals for analysis. The explanation can be found only in a detailed consideration of all the environmental factors. The first three groups of these animals were quartered in a single large pen, divided into three parts by wooden partitions of tongued and grooved siding. The top and front side were made of inch mesh wire netting. There ms no chance, therefore, for the excreta of one group of animals contaminating the food of the others; nor could dust from one cage enter the other in considerable quanti ty. When the animals were treated, they were kept on the yniffigti board until the treated surfaoe was dry, before being retained to the cages. No special ventilation was employed, since there ms no ob jection in this case to Inhalation of gasoline and tetraethyl lead vapor. (In the case of human exposure, both of these possibilities are presented), under these conditions, the opportunity for inhalation of vapor from treated animals was not presented to control animals. K? 0017006 Rio cause for the experimental result can he found only in a condition to which all of the animals were equally exposed. One end of the large room, which was being used for housing the animals during the cold weather, was used from time to time as a place of storage for returned pack ing cases filled with empty and full cans used for the early distribution of tetraethyl lead. It is apparent, and should have been foreseen, that a quantity of the dust resultant from the decomposition of such a portion of tetraethyl lead as was left in these cans aec-asulated on the floor of the room and was carried by currents of air, and the feet of attendants, to that portion of the room used by the animals. It is almost certain that the food of tho animals was contaminated as well. In this manner the animals ingested inhaled such quantities of lead as to completely spoil the experiment. Analytical Results ** March 3rd. 3 Guinea pigs -Pan Ko* 1. 2.10 - 2.10 - 2.55 " " " 2. 2.00 - 2.00 - 2.10 3* K w w 3. 1.60 - 2.00 Beaker broken analysis spoiled. Analysis Repeated March 31 as Check. 1 Guinea Pig - Pen So. 1. ?/hite buck, weight l-ll/l6 lbs. 1" M M 2. White and black female, weight 1-3/16 lbs. 2.65 2.10 As a result of the error in the manner of conducting this ex periment, no conclusions may be drawn as to the quantity of lead which may have been absorbed from the leaded gasoline. It may be of some significance. however* that the quantity of lead absorbed frcm the gasoline, If any. Bade no appreciable difference in the total lead obtained from all sources. Such variation as occurs in the entire group of animals may he explainable on the basis of variations in weight. It is certainly significant, that even under these adverse conditions, there ms no demonstrable evidence of the poisoning of any one of these animals, unless the miscarriages be considered. This is of extremely doubtful signiflcairns* sinoe such occurrences are not infrequent In a group of this masher of animals in any environment. M0IIKBI7S Monkey Ho. 1 Rhesus J&le Weight 5-l/s lbs* Treated with 2 cc. Ethyl Gasoline daily. Euraber of treatments 88. Jan. 19 This monkey Is now lively* apparently perfectly well* is tame, playful, and In good condition in every way, except for some degree of irritation of the shin of his back. In February he ms somewhat ill, and lost his appetite. The weather was bad at this time and all the animals were exposed to too low a temperature for a few days. The animal lost weight at this time, dropping to 4~l/8 pounds. Subsequently he improved* regained weight slowly, and now weighs 4-13/16 pounds. Blood examinations when received indicated the following con ditions* Red count, 4*144,900; YThite count, 13*800; Haemoglobin, 85. Smears showed no variation from the normal appearance of the erythrocytes. Examination of the blood has been made at regular intervals up to the present. Only slight variations of the erythrocytes have been seen. 0017308 .- 9 The leucocytes have varied nruoJi ore* The last examination, May 15th, is as follows* Bed count, 4, 900,000? TTnita count, 10,500; Haemoglobin, 90. Smears showed an occasional erythrocyte taking the basic stain to a slight degree. Ho stippling, and no other abnormality is found. Krynkey Ho. 2# Bhssu Female Weight 6-l/4 lbs. Treated with 2 cc. Ethyl Gasoline daily* Humber of treatments 08. Jan. 19 This monkey in normal in every discernible way, except for the development of an elephantiasis of the vulva. She is lively, and playful, though she bats not developed the taraenesa of the other. She, too, was ill in February, lost a little weight, developed sniffles, and ate but poorly for several days. She regained the weight sub sequently, apparently recovered entirely, weighing now 8-l/8 pounds. Tiie initial blood examinations showed the following results* Bed count, 5,020,000; White count, 16,400; EaasBOglobin, 90. Smears showed no evidence of any abnormality. Blood exaninatione have been made on this animal. There has been no significant variation in the enumeration of the blood elements, nor has the blood picture developed ax abnormalities. The last examination- Kay 15th, was as follows* Bed count, 5,700,000; White count, 8,700; Haemoglobin, SO. Smears showed an occasional basophilic erythrocyte. Ho stippling found. In April the animals concerned in the above experiments were mov ed into different quarters, which allow of no opportunity of exposure to lead in any way other than under controlled experimental conditions* Treatments are be ing containued to determine if symptoms and signs of poisoning can be produced by the experimental methods previously outlined. .Kf 0017309 TUB HAZARD OF LEAD POISOHIHG FHCfiJ SEE HAED1IEG tm tamo OF e t h y l g a s o u e e The interpretation of animal experimenta in terms of human beings is at best & questionable pxoceedure. When one is determining the toxic properties of a general protoplasmic poison, a reasonable assurance exists as to the qualitative import ance of the experiments* The quantitative value of such experiments is always a matter of doubt* This, because of certain variations in the physiological mechanisms of different organisms, and because of un avoidable variation in the manner and rate of introduction of the mat erial in question, into the tissues of various animals* The interpretation of the hasard existing free; the handling and use of "Ethyl Gasoline", in terms of animal experimentation is doibly questionable, because it is Impossible to duplicate the actual conditions under which such handling occurs* An attempt was made to orr on the side of an increased exposure of animals over that likely to occur* Whether or not that was accomplished is a matter of judgment* In this situation, the advisability of making obser vations in the actual field of operations, s^geeted itself months ago Accordingly arrangements wore made for the careful taking of histories of exposure, the making of careful physical examinations, and the analyses ME 0017310 of specimens of urine and faeces of a considerable number of men who bad been exposed to actual conditions over a considerable period of time. The opportunity to do this mis present in that employees of the General Motors Eesearch Garage, and of the Dayton Power and Light Company, and of the Befiners Oil Company of Dayton, had been exposed to all of the condi tions which could possibly bring danger of lead poisoning from the dis tribution and use of Ethyl Gasoline and from the use and mechanical care of cars using Ethyl Gasoline, and over a considerable period of time. (It must not be supposed that these e bb had been carelessly allowed to assane these dangers without any knowledge of then, or without medical observation at regular intervals. The fact remains, however, that the early methods of use and distribution of Ethyl Gasoline were of such a sort as to present hazards of such a magnitude as will never exist under 'U the present methods of use and distribution.) Full data is available as to the histories of ex posure, the physical findings, and the clinical symptoms of these men. Analytical data will be presented on as many of them as are now available. The following table presents in brief the items of importance found in the analysis of these data. 0017311 3 General Motors Besearch Garage BefInara Oil Co. at Dayton 2 Dayton Power and Light Company 23 Persona Examined Mechanics Handlers of Ethyl Gasoline Drivers 3 2 5 2 1G History as to Exposure Total IIumber Exposed Hot less than 2 yrs* Hot less than lyr. 30 26 S Less than 1 yr. 1 HoadAehe Loss of Weight Symptoms appearing in Thirty Men exposed to Insom nia Ethyl Gasoline and Exhuast Gas. Disturb- ing dreams Polyaria Gastric Digestive Cramps Disturbances Weakness 1 1* Hone 2** Hone Hone laan Hone Hotes: * ** *** This man lost weight following an attach of cholecystits. Both of these men gave a history of dreaming for years and ad mitted the condition only after leading questions. This man gave a history of diarrhoea and fever, followed by constipation. i * PHYSICAL SIGHS APPSARIEG IK THIRTY HEH EXPOSED TO ETHYL C-ASOLIFS ADD EXHAUST GAS* --------,, m.wnsWMtT;. 4. Sub-normal Pallor Temperature. Bradyoordla Sub--norrsal Lead Low Blood Pressure. Line Stippling Haemoglobin 24 S (97.6) 1 (97.2) Hone ________ 4________ (1) 114-72 {IT 112-70 (1) 110-74 (1) 106-66 Hone Hone 2 Kotoss Of tho two showing pallor, one has a ohronic cholecystitis and the other has a history of tuberculosis of long standing* The other findings are of no more frequent occurrence than may be seen in any group of men tsdcen at random, and they are explainable on tbs basis of other physical findings such as very bad dental condition,, existance of common colds# etc. At the same time, sixty four men# at no time exposed to EtJyl Gasoline# have been questioned as to the details of their employment for the past several years and have been carefully examined. Specimens of urine and faeces have been obtained for analysis so an to furnish a comparison with, the previously examined exposed man. A detailed analysis of the data obtained from unexpo aed men. ae to their histories and the results of physical examinations would require too much space for the present needs. However# the data now available as to the results of the chemical examination of specimens of urine and faeces are appended hereto. coaTOLGaiagg A careful consideration of the results of the examination of thirty men who have been exposed over a period of about two years, to one or more of the hazards arising from the general distribution and use of Ethyl Gasoline# fails to show my evidence of the appearance of either symptoms or signs of lead poisoning. Appended hereto are data as to the analyses of urines and faeces. They are as yet incomplete and are submitted for what thev ey*> wmtv. KE 0017313 ' 'v^ 5 Analytical Bata from gen Men Exposed to Ethyl Gasoline (Hoc. 13, 14, 15 and 17 were also exposed to ondiluted fluid containing tetraethyl lead and ethylene dibremida for a considerable period of tics. See history) Average Sample Urine (0*182 mg* (1525 c*c* Urine Average Sample Feces (0*519 (32*05 gm. Dried Feces Sample 1 3 4 6 8 11 IS 14 15 17 0*12 mg* per liter Urine 1*57 mg* per 100 gn. dried feces. Weight dried feces in grams mg* Vol. Urine in c.c. Big. 27*4 21.1 11.1 4*5 40.2 29.8 7.8 117.3 33.0 38.3 0.50 0.32 0.11 0.14 0.65 0.32 0.30 1.91 0.29 0.65 700 1200 3000 470 1200 1500 1400 2900 1350 1530 0.14 0.17 0.22 0.12 0.17 0.08 0.10 0.14 0.56 0.12 May 18, 1925. FESD3RIGK fHMAESJ. HE 0017314 6 Analytical Data front gen Control (Unaxpoaed) Workmen. Average Sample Urine Average sample Faces (0*091 mg* (1473 o*o* Urine (0*38 mg, (27,32 gm. Dried Fecea Sample 29 68 74 77 78 80 81 32 83 84 0*06 mg. per liter Urine .. 1*36 mg* per 100 ga* dried feces. Weight dried feoes in grams 22.7 35*6 45.4 50.0 11.8 18.3 28.4 7.8 32.8 23.4 mg. 0.74 0.32 0.24 0.22 0.16 0.22 0.14 0.18 0.58 0.54 Vol.Urine in e.c. 2200 1650 1300 1180 . 1850 1320 1400 1950 710 1170 mg. 0,14 0.11 0.15 0.07 0.15 0.10 0.07 0.05 0.07 Hil