Document KJqwaKg2a2OZrk8gGwmZnzJ22

EXPSUSSNTAL STUDIES car TETRAETHYL LEAD P0I 3CETI B3 BT ROBERT A. KEHDB# H.D. EICHBERO LABORATORY OP PHYSIOLOGY, UNIVERSITY OP CINCINNATI, CINCINNATI# OHIO. ASSISTED BY THE STAFF OP THE RESEARCH LABORATORY OP THE ETHYL GASOLINE CORPORATION DAYTON, OHIO K 0017786 THE TOKIOITT OF TETRAETHYL LEAD. The toxioity o f tetraethyl lead for rabbits has teen 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 ohly the lethal amount for a single administration he 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 kilos outaneously 0.7 oc. per kilo body weight, or about 0.7 grams lead per kilo; b y 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, bnt 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. - 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 tbs 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 0.011 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. A n 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 - 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 proa used b y 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 O.l c.o. 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 sidration 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 the AOOunauLfiar a r m s nr experimehtai, AEIMALS TREATED WITH TETRAETHYL LEAD , When rabbits are treated at regular intervals with soblethal doses of tetraethyl lead, there is an acaunrulation of lead in the body of the animal 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 whioh has elapsed between administration of the last dose and the time of analysis of the animal* That is, the rate of seoretion 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 accumulation 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 m y 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 0017790 -2 Rabbit no. 31 Weight 5-3/8 # Ho. 34 6-4/s # HO. 35 6f HO. 36 5-3/4 # HO. 37 6-3/4 # Ho. 39 4-7/8 # Ho. 40 HO. 42 4-1/2 # 4-5/8 # HO. 60 3-1/2 # Humber of Treatments 16 13 15 17 7 14 14 11 10 Tim of Appear ance of loss of weight. Result Lead Determ ination in milligrams 7th treatment Died 23 days after last treatment. 15.3 Ho loss of weight Same 9.78 8th treatment 14 th ff Died day after 15th treatment Survived 96.0 7th n 7th 9th n ft 7th Died after 7th treatment Died 29 days after last treatment Survived Died after 11th treatment mismmgxrm faaac Survived 90. 7.10 51.25 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 case 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 lead free animals as controls. The diets of the animals were unchanged during the period of collection. KE 0017791 Babbit 2 controls Ho* 31* Ho* 36 Bo* 39 Period of Collection 7 days ' 7 7" 7* Quantity of Lead in Milligrams mi 5*89 4.00 2*03 notes This animal died Beoeiriber 21* Hi a entire tody contained 15*3 Big lead Souse idea can be obtained of the quantity of lead in the body of this animal at a tine -when he as excreting almost 1 xag, 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 m y not be formed which is more readily excreted than the ordinary compounds of lead. This question is presented the wore strongly when the rate o f excretion of lead in men poisoned by tetraethyl lead is studied* zo o r r* Q*j TES DISTRIBUTION OF LEAD IN 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* Babbit No* 32 - Exposed for 72 days to vapor of pb (Et ) in air at the rate of 100 oe* Pb{Et)4 vapor to 5 liters of air* Tissue Bones Skin Liver and Kidneys Central Nervous System Fetuses in Utero Other tissue Weight 225 grams 300 55 " 13 125 " 2045 M Lead in Milligrams 9*15 3*16 3.70 Nil 0*26 8.75 Note* One liter of saturated vapor of FbfStJ^ at 25* 0* contains 0*00456 grama PB* 2. Babbit Ho. 31 - Treated every three days with 0*1 cc. fc{Et}4 , sixteen treatments* Died twenty-three days after last treatment* Tissue Weight Lead in Milligrams Bones 325 grams 8*04 Skin 260 4.49 Liver and Kidneys 105 1*15 Central nervous System 13.5 Lost in analysis Other tissue 1590 * 2.02 Urine in Bladder 50 e.o* 0*14 Babbit Ho* 16 - Exposed for ninety-dight days to vapor of PbtEt)^ in air at rate cf 5 ce* of Pb(Et)4 ^ p o r to 5 liters o f air, and then for three days to 200 cc. vapor in five liters of air. Pied* Tissue Weight Lead in .Milligrams Bone s 520 grams 2.22 Liver 82 3.75 Central iiervous System 18 0.13 Remainder (without shin) 2160 26.00 KE 0017794 SHE EFFECT OF TETRAETHYL LEAD OS AEB2ALS When toxic amounts of tetraethyl lead are administered to rabbits, the first symptoms seen are Inch of appetite end loss of weight# A sluggishness and lassitude are apparent, and the aninal sits with drooped ears and arched back# As the symptoms increase in severity, he becomes nsrvcuc, soring about in the cage from place to place, stopping from time to time to sink into a drowsy state# She tenxperafcure does not ordinarily vary more than is normal in these animals, hut respiration quietens at first and than, with in creasing severity of symptoms, decreases# If sufficient time inter venes before death, a watery diarrhoea develops# Convulsions usually occur as a terminal sign, and the animal dies with bulging, congested eyes and paralysed respiration, sdth the least continuing for some time afterward# When illness results from inhalation there is an irritation, with some -weeping o f the mucous membranes# The upper respiratory tract ay 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# Rapid peristalsis may be easily observed under the abdominal wall# During the course of their illness, whether acute or prolonged, no characteristic objective signs develop# There is t o typical alter ation of the blood picture# {Stippling and polychromatophili^ are found almost uniformly in normal rabbits, so that no minute changes 0017795 w o l d te demonstrable*) Only a slight anemia tea appeared In any exper imental aalaal thus far* Post-mortem examination of poisoned ani jails discloses certain characteristic though not definitely differentiating changes* These are confined almost wholly to the alimentary tract and the central nervous system* Thera is a considerable amount of capillary dilitatlon of the viscera generally ted the heart is ossally dilated and flabby, but the pronounced findings are seen In a n tenth intestinal irritation end desqua mation and an acuto edema of the brain* The intestinal change is confined almost holly to tbs small intestine ted Is most pronounced is the duodenum* Here the intestine is filled with a stiofcy mucoid fluid which may be, but usually is sot* blood tinged* It is characteristically yellowish and glairy* and often coagulates spontaneously on standing for a time* The mucosa in this region is thin and almost fluid in character. Bo actual ulcerati cm is found* and there are seldom any definite haemorrhagic areas* The brain is either dry and swollen and very friable* or else it is very wet with a large amount of free fluid under the dura* especially at the base* Microscopic findings are vary meager* Bo characteristic change has been found* The study of microscopie pathology has not been compieted* Among the effects on experimental animals* which should be noted in passing is the influence of lead poisoning on pregnancy and the procreative functions in general A number o f pregnant female rabbits lavo given birth to pranature litters* In several cases abortion or miscarriage has resulted shortly after the administration of the poison. However* the loss of ability to reproduce has not occurred in the case of either male or female rabbits* Animals which hate teen severely poisoned have both fertilised and become impregnated and have brought forth normal young after only brief period of recove OH THE ABSORPTION OF TETRAE3ETL LEAD THROUGH THE SKBf, AHD THE ABSORPTION OF TETRAETHTL LEAD OUT OF CASOLIHB* In the former experiments, in which the toxicity o f tetraethyl lead as absorbed through tbs skin, was determined, there was in almost egery case a possibility that tbs animal had obtained a portion of the 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 disoever whether tetraethyl lead could be absorbed * through the skin oat of gasoline* The practical importance of the latter question lay in the fact that the exposure to tetraethyl lead, on the part of distributors and eenswaers, would have to do with this solution In contact 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* 0017797 -2 The following experiments show that tetraethyl lead may he absorbed through the shin 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 -which may be absorbed out of a solution of tetraethyl lead in gaso line comparable to commercial **sthyl G-aaoline", is very minute* Sroeriiaents* : . 1* Three rabbits of approximately the same wfcight (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 approximately 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 tee&tments, the animals developed par alysis of the hind legs, and on the next day they died* Control animals, two in number, of the same tight, treated in exactly the earns manner, mm 0 except that the gasoline contained no tetraethyl lead showed no In dication of injury beyond sene degree of irritation of the olein* 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 l-l/2 hours to 105 oo* of a solution containing approximately 10 grams of lead* Approximately 0*35 of 1% was absorbed* 2* Ten rabbits were 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 exposureswere made twice weekly* This was dona because of th8 skin irritation which resulted from the daily treat ment* Zt was found that the skin could be kept Intact by increasing the interval between exposures, provided the Skin be treated vdth cold cream in the interval* The following table shows the results of such treatments Ho. Animal 89 control 93 ft 98 ft 90 1* 100 91 1: 100 92 1: 100 No. Treatments 28 27 27 7 29 29 elgfct Before After 2- 3/ 4 5- l/ s 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- l/ e Result Survived ft ff Killed for analysis* Survived ft Ho. Animal 94 It100 95 ItlOO 96 It 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 mniMia iiillMMMfifijHSi - Am He suit Hied suddenly with out previous illness** 111 after 10th treat ment. Recovered. Survived. Paralysis 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 he 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, i.e. one to ten. OH THS 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 volatilising out of gasoline at the existing concentration l[1.1300 approximately) is sufficient to causa appreciable ab sorption of lead; (b) whether s n absorption of tetraethyl lead in gasoline can occur to an extent sufficient to cause poisoning. Hotet Grom the Research Laboratories of the Ethyl Gaso line Corporation and the Eichberg Laboratory of Physiology, University of Cincinnati, Cincinnati, Ohio. 001 730 Both of those problems ere investigated by exposing animals to conditions as nearly like the normal conditions of human exposure as could be devised For this purpose guinea pigs end 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 groups, kept separate, but fed and oared for in exactly the same manner Eleven pigs, four females and the remainder males, were treated on the skin surface of the belly, after clipping off the hair, with 1 oc of ethyU s e d 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 used was a good grade of high test cocraercial 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 be to 200 oc. 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, and two were treated daily with 2 oc. of Ethyl gasoline, prepared in the above manner I The hair was d i p p e d from aa area on the hack, as large as the palm of the hand and the gasoline mixture was dropped on out of a pipette* One of the monkeys to he 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 o f exposure before he could he captured* The two being treated as above were continued without any controls for eompari son* The following paragraphs indicate the course of the experi ments carried out upon these animals* GUlHm PIGS. Pen Ho* 1. 4 females 7 males treatments twice weekly. Treated with 1 cc. Ethyl Gasoline* Humber of treatments 40* In the period from Hovember 25th* to the present there have heen no natural deaths among these animals* Three were killed for analysis on March 3rd* and one was Milled 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 b o m 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 Method) 90, Bed Count* 6*160*000 (h) Hb. 110, * 5*200*000 0017303 Observations made on fifey 17th, wore as follows* (a} Hb. 90 Bed Count, 5,754,000 (b) Hb. 105, M 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* Share has been no noticeable increase in the number of these* S M M Of the 7 pigs rem i n i n g 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 upon 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. 0017304 Two pigs were selected for their distinctive markings, and blood examinations were made as in the case of group So* 1 Ho variation was seen in the blood picture, and no variation as coopered with those in pen Ho, 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. So 6 Pernales 5 Bales Treatments twice weekly. Treated with 0.2 co. Ethyl Gasoline. Sftaber of treatments 40. Since Hovember 25th, the beginning of the experiment, there have been no deaths among these animals as a result of illness. Three were killed for analysis on March 3rd, Twenty-four young ones have been born, of which nineteen are now alive. The others died within a day or two of their * birth. There have been three litters born dead. Hone of these occurred since April 1st. The blood findings in these animals are no more significant than those in the other groups of pigs. Ho 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 twioe weekly. Treated with 1 co. Gasoline. Htmiber of treatments 40 There have been no deaths in this group. Two litters of young have been born, six young in all, of which one was dead at birth. blood exam in ations have been made on the pigs in this pen 001 7i o0*>1Jor oinoe the first examination. Tbey ere sod largely as controls on the influence of the gasoline alone on the skin. Ho variation is soon either in the condition of their skin, or their general appearance as compared to treated animals. An unfortunate and unforeseen variable m s 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 was 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 tangoed and grooved siding. The top and front side were made of inch mesh wire netting. There was 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 animal board until the treated surfaoe was dry, before being returned to the cages. Ho special ventilation was employed, since there was 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), dder these conditions, the opportunity for inhalation of vapor from treated animals was not presented to control animals. 0017306 *Fho cause for the experiiaontal result can be found only in a condition to which all of the animals were equally exposed. One end of the large room, which was being m e d 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 m e d for the early distribution of tetraethyl lead. It is apparent, and should hare 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 acetBrulated 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 fcy 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 -- larch 3rd. 3 Guinea pigs - Pan Ko* 1. 2.10 - 2.10 - 2.55 3 3 ft K " " 2. " 3. 2.00 - 2.00 - 2.10 1.60 -- 2.00 Beaker broken analysis spoiled. Analysis Repeated March 31 as Check. 1 Guinea Pig - Pen So. 1. White brush, weight l-ll/l6 lbs. 1 ** " M H 2. White and black female, weight 1-3/16 lb* 2.55 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 hare been absorbed from the leaded gasoline. It may be of some significance. however that the quantity of lead absorbed from the gasoline, if any, made no appreciable difference in the total lead obtained from all sources* Such variation as occurs in the entire group of animals may be explainable on the basis of variations in weight. It is certainly significant, that even under these adverse conditions, there was no demonstrable evidence of the poisoning of any one of these animals, unless the miscarriages be considered* This is of extremely doubtful significance, since such occurrences are not infrequent in a group of this ntenber of animals in any environment* HOEKSTS Monkey Bo* 1 Rhesus Male Weight 5-i/ lbs. Treated with 2 cc. Ethyl Gasoline daily. Humber 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 baofe* In February he was 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 -I3/I6 pounds. Blood examinations when received indicated the following con ditions Bed count, 4,144,900; Vihlte 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. K 001 -- 9.' Th leucocytes have varied much more. The last examination, XEsy 15th, is as follows* Bed count, 4, 900,000* Whits count, 10,500? Haemoglobin, 90. Smears showed an occasional erythrocyte t&Jdng the "basic stain to a slight degree. Ho stippling, and no other abnormality is found. Eohkey Ho. 2# Bhasus Female Weight 6-l/4 lbs* Treated with 2 cc. Sthyl Gasoline daily. Humber of treatments 08. Jan. 19 , . This raorilcey is normal in every discem&ble -nay, except for the development of an elephantiasis of the vulva. She is lively, and playful, though she has not developed the taraeneaa 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. The initial blood examinations showed the following results* Ked count, 5,020,000; White count, 16*400; Haemoglobin. 90. Smears showed no evidence of any abnormality. Blood examinations have been made cm this animal. There has been no significant variation in the enumeration of the blood elements, nor has the blood picture developed any abnormalities. The last examination, Ihy 15 th, 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 intc 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 THE HAZARD OF LEAD POISONING . FBQ25 THE HASSLING /IH> USING OF ETHYL GASOLINE The Interpretation of animal experiments in terms of human beings is at best a questionable pxooeedure. whan 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 physiologies! mschanioma 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 doubly questionable because it is impossible to duplicate the actual conditions under which such handling occurs An attempt was made to err 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 suggested itself months ago Accordingly arrangements ere made for the careful taking of histories of exposure, the making of careful physical examinations and the analyses of specimens of urine and faeces of a considerable number of men who had been exposed to actual conditions over a considerable period of time. The opportunity to do this was present in that employees of the General Motors Eesearch (Jarago, 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 couia 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 b b had been carelessly allowed to assane these dangers without any knowledge of them, 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 Jthe present methods of use and distribution.} ' Pull data is avaibble 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 o f these data. General Motors Kesearch Garage 5 B e finora oil Co* at Dayton 2 Dayton Power and Light Company 23 Persona Ugandas& Mechanics 1 Handlers of Ethyl Gasoline 1 Drivers - , 5 2 2 1G History as to Bgposure Total Humber Exposed Hot less than 2 yrs. Hot less than lyr. 30 26 3 Less than 1 yr 1 Head Ache Loss of Weight Svtaptoas appearing in Thirty Men exposed to Insom nia Ethyl Gasoline and &xhuast Gas Diaturbing dreams Polyaria Gastric Digestive Cranros Disturbances Weakness 1 1* Hone 2** Hone Hone lauta Hone Hotes: * This man lost weight following an attach of cholecyst its. ** 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. K 001 *r* i^ $ : PHYSICAL SIGHS APPEARIEG IK THIRTY HBH EXPOSED TO ETHYL 0AS0LIF5 AITO EXHAUST GAS* 4. Sub-normal Pallor Temperature. Bradveordla Sub-nom a l Lead Low Bicod Pressure. Line Stippling Haemoglobin 24 3 (97.6) 1 (97.2) Hone 4 (1) 114-72 {IT 112-70 (1) 110-74 (1) 106-66 Hone Hone 2 Kotos: 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 taken at random, and they are explainable on the basis of other physical findings such as very bad dental condition,, existance of consnan colds, etc. At the same time, sixty four men, at no time exposed to Etiyl 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 fasces have been obtained for analysis ao as to furnish a comparison with the previously examined exposed man. A detailed analysis of the data obtained from tcaexposed men as to their histories and the results o f 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. CGHCLHglOHS 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 m y 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 e w 5 Analytical Bata from gen Men Exposed to Ethyl Gasoline (Nos* 13, 14, IS and 17 were also exposed to tindiluted fluid containing tetraethyl lead and ethylene dibromide for a considerable period of tins. See history) Average Sample Urine (0.182 mg, (1525 c.c. Urine Average Sample Paces (0.519 (33.05 gm. Dried Feces 0.12 mg. per liter Urine 1.57 mg. per 100 @n. dried feces. Weight dried Sample feces in grams mg. Voi* Urine in c.c. Big. 1 27.4 0.50 700 0.14 3 21.1 0.32 1200 0.17 4 11.1 0.11 3000 0.22 6 4.5 0.14 470 0.12 8 40.2 0.65 1200 0.17 11 29.8 0.32 1500 0.08 IS 7.8 0.30 1400 0.10 14 117.3 1.91 2900 0.14 15 33.0 0.29 1350 0.56 17 38.3 0.65 1530 0.12 Hay 18, 1925. FEHDSEICK EHHASH. 6 Analytical Data from gen Control (Unaxpoaedl Workmen Average Sample Urine Average sample Faces (0.091 mg (1473 oe Urine (0.38 mg. (27.32 gm. Dried Feces Sample 29 68 74 77 78 80 81 @2 83 84 0*06 mg. per liter Urine .. 1.36 mg. per 100 ga. dried feces. Weight dried feces 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 V o i .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 Kil