Document JJn6qoy88Nwp0mzY68N9vJ1D2

C orrespondence fro m Dir. E . D R eports on A ssociated E th yl O p including a n a ly tic a l data on m en Oi NO S NO o Z o -< n O o 3 OjD oo <; o rj <1*i 0 CO 10 >0 z (D O Z sc: on 7s rn OCIATED ETHYL COMPANY LIMITED NORTHWICH CHESHIRE llephone: NORTHWICH 324l/7. -Y ~,tead Office- ARTILLERY HOUSE ARTILLERY ROW, LONDON, S W 1. ABBEY 3974 OUR REF. L*<* YOUR REF. ' Sfelee/rams&Cables: ETHYLPORT, NORTHWICH. DATE 14th December, 1950. Dr. R.A. Kehoe, Kettering Laboratory of Applied Physiology, University of Cincinnati, College of Medicine, Cincinnati, OHIO, U.S.A. Dear Dr. Kehoe, I have been instructed by Mr. Bevan to give you the details of an incident which occurred here recently. We have no data of any value for comparative purposes, but are sure that you will have some in your possession, and will be able to advise Mr. Bevan on this matter. I understood from Mr. Bevan this morning that when the case is complete, so far as completion is possible, the Company will give the findings to H.M. Inspector of Factories (Alkali). Me will forward the analysis of grass samples by cable when we finish them. 1 The incident is as follows In the early afternoon of Tuesday, 2Gth November, I was informed by the Works' Manager that Mr. Wilson, Veterinary Surgeon, Northwich, had informed him that a colt foal had been found dead in a field adjacent to the Plant. I contacted Mr. Wilson, and arranged to be present at a post mortem on the animal on the morning of the foiloiling day. At the post mortem on the colt, on the morning of Wednesday-, 29th November, it was estimated that the colt had been dead a little more than 24 hours. It was in good condition, and the immediate cause of death was pneumonia. A considerable part of the lung had progressed to the stage of hepatisation. I had a vague idea that in the Selby Smelter Commission report, the death of horses had been the subject of comment, and that pneumonia of inhalation or aspiration type was not uncommon in animals suffering from chronic lead poisoning, the result of paralysis of the muscles of deglutition. There was no evidence of any foreign bodies in the lung, and macroscopic examination of the trachea, which was full of fluid, appeared normal. There was also a slight excess of fluid in the abdominal cavity. The owner, a local farmer, had not noticed anything wrong with the animal, ncr anything peculiar in its behaviour. The veterinary surgeon was satisfied as to the cause of death. I took the following samples as a precaution: ''iver, kidney, upper end of femur, tooth, lung and spleen. The colon was loaded, KS' 0010037 (Contd). and some of the contents were stripped into a bottle. The same afternoon, the veterinary surgeon phoned me, and stated that the mother of the colt, which had been lost, had been found dead, and that another grey horse was seriously ill. The latter was subsequently shot, and I attended the post mortem on both these animals the following morning. The mare was partially dismembered when I arrived. Most of the organs were in an advanced state of decomposition. This animal probably died at about the same time as the colt. There was no obvious cause of death. Samples of tissue were taken from the following organs: liver, kidney, femur, muscle and lung. The grey horse had an apical pneumonia, which the veterinary surgeon stated was not sufficient to account for the illness. Samples of the following organs were taken from this animal: liver, kidney, radius, heart blood, brain, muscle and lung. The veterinary surgeon took duplicate samples. Fortunately, another horse came in from a farm at Little Leigh, five miles from the Plant. This animal had died from a septic arthritis. To me, this seemed to be a synovitis of the joint between the hooves and the legs. Samples taken from this animal were liver, kidney, radius, heart blood and muscle. All samples of tissue were definite!;/ from the animals described above, with the exception of the sample of the femur of the mare, which was taken from a bin containing dismembered parts of animals, and which was stated to belong to the mare. The analysis was carried out by the method of Bambach and Burkey, and the results are shown on the attached table. During analysis, a little lead may have been lost, as some of the dishes cracked, and the samples had to be transferred. The three animals, which had grazed in the fields near the Flant, had absorbed significant quantities of lead, and in the case of the colt, it would anpear that the absorption had been going on for some considerable time. The colt was from 6 to 8 months old at the time of death. If the immediate cau.se of death was not directly the result of this lead absorption, it is not impossible for the terminal illness to have been aggravated by it. As long as two years has elapsed between the bursting of autoclave discs. Of recent months, there has been a spate of these. So far as I am aware, four occurred during the month of November, and there were at least two in October, associated with fire, one of which lasted for 50 minutes. Some of the lead--bearing material from the autoclaves does find its way to the adjacent fields, but in my opinion not to any great concentration. You will remember the dead recovery building-; this has a reverberatory furra 'e, which deals with the dried sludge. The chimney from th is 130 feet high, and the fumes from the furnace have direct access to the atmosphere through it. The estimated quantity of lead going up this chimney is 200 pounds per day, and as the furnace is in operation about 340 days a year it would seem that approximately 30 tons of lead per annum are deposited over the countryside. The r use-Anthony scrubber has never been satisfactory, and HE oojo&3fc (Contd) To: Dr. R.A. Kshoe 14.12.50. -3- at best has only worked intermittently. Apart from technical difficulties in construction, there has neverbeen enough water to operate it. At times, this chimney "snows" on to the surrounding ground, and has been a source of complaint on my part for years. I feel that it is the most likelj- source of lead contamination of the fields in the vicinity of the Plant. The enclosed map shows the locations from which samples of various crops were obtained for analysis, and also the approximate areas from which grass samples were taken recently. The crop sample analysis has been accepted as correct after some discussion. The analysis for the first time was carried out by us by the Bambach and Burkey method. The grass samples, which were taken by the Plant Management subsequent to the death of the horses, have not yet been analysed, but ve will cable these results, we hope/towards the end of.,next week. The prevailing wind here is from the South-West. matter. We would all be most grateful for your opinion and comments on this , With kindest personal regards to you all, and all best wishes for Christmas and the New Year. Yours very sincerely. --^iCl. B. Davison. HE 0010039 T ?? VKO) < 2 vfD hi `X) M C4D oO H oOfo--' Ha* OCD P c+ P tco+ M CD P to cpo* h HORSi!) SAMPLES. 7 th Dece tfg 0010040 iraj: t(nD tU0>4 -J (-> o wVjJ oo Hoo TO o ro f" TO *>- v_n OTO o o M o vOn u* o 5P c*- s TO. *M6 O ffi -b Kry s. pssEj A-X * i- 0010041 rw A N KE' 0010043 CffOWM C O PYR IG H T R B S E ftV E D. ANALYSES 0? LOCAL GRCE SAIEIEC - I960, .;overaDe: 1950, Semple Ho. Type. National Grid Ref. ffi lit. of Sample Taken, 1-lgms .nb/ 100 gms. ITgm. Pb/KgE or p.p.m. 22.3.50. 22.3.50. 1. Gats ChaffStrau 2. vfheat Chaff Strau 7066-7465 50 gms. 45 gms. 50 gms. 7077-7430 100 gmse 25 gms. 50 gms. 2.24 133.2 160 .0 1.22 11.28 3.04 22.4' 1332.0 1660.0 12.2 112.8 30.4 22.8.50. 3. Oats,Earley Chaff Strau 6960-7453 50 gms. 25 gms. 50 gms. 1.34 5.63 4.34 13.4 56.3 48.4 22.8.50, 4. Oats Chaff Strau 7057-7463 50 gms. 25 gms. 50 gms. 2.34 51.2 68.0 28.4 512.C 630.0 19.7.50. 5. Kay 7063-74S0 50 gms. 62.0 620. C IT. Trevor Larlam, 23.11.50. 6" Ordnance Cheshire Sheets 22217 9 LTJT "*-T 1903 S: 1938 Editions O '< V QU C* 4ij*) Location of Furnace Chimney - Grid Ref. 7045 - 7470. k 0010046 POTENTIAL SOURCES OF CONTAMINATION OF THE COUNTRYSIDE. Summary* Northed.ch Plant. Main Source. - East side of Plant. High Level. Constant Inorganic Organic "BM Building. ) From chimney and exhaust sts "A" and "G" Building. ) wastes. Dust deposited fr< these on' roofs, etc. Occasional. Burst autoclave discs or venting of autoclave vapours and fumes to atmosphere. \ c 1. August, 1950. 2. August, 1950. General view of exhaust stacks and chimneys from the S.W. Main Source - Chimney of reverbatory furnace, "B" Bldg. Total lead liberated to atmosphere about 200 lbs. per day in 1950. Size of Particles. Those causing heavy local deposition are the siaeof snow flakes, confetti, sand and pepper. Wind very variable, mainly S.W. Main Source East side of Plant. High Level. Constant Inorganic Organic "B" Building. ) From chimney and exhaust sts "A" and "G" Building. ) wastes. Dust deposited frc these on roofs, etc. Occasional. Burst autoclave discs or venting of autoclave vapours and fumes to atmosphere. 1. August, 1950. 2. August, 1950. General view of exhaust stocks and chimneys from the S.W. Main Source - Chimney of reverbatory furnace, "B" Bldg. Total lead liberated to atmosphere about 200 lbs. per day in 1950. Size of Particles. Those causing heavy local deposition are the size;of snow flakes, confetti, sand and pepper. Wind very variable, mainly S.W. 3. August, 1950. 4. August, 1950. Note variation in direction over a short period. Taken from Consulting Room window. US' 0010048 5. August, 1950. 2- - 6. August, 1950, Taken from N. door of input fan house, HA" Building. 7. August, 1950. Same chimney waste as 6. This deposited a heavy deposit of sandy material on the floor of the fan house. 8. August, 1950. Particles of confetti size were deposited on the farmyard from this. KC 0010049- 6. August, 1950 T&ken from N. door of input fan house, "A" Building. 7. August, 1950 Same chimney waste as 6. This deposited a heavy d eposit of sandy material on the floor of the fan house. 8. August, 1950. Particles of confetti size were deposited on the farmyard from this. 9- 3^8.1950. The white patches on the concrete at the East of B" Building are from "snow flake" sized flocculations from "B" Building chimney. Kg' 001005J3 9. (a) Low Level Sources. 1. Drum graveyard - broken down scale, etc. 2. Dust from roadway on East side of Plant, including Farmyard dust and fumes. 3. Liquid contamination: Surface washings, "G" Building. Blocked chemical drains. Surface washings, "B" Building area, including overflows from "pad11 of sludge water. 10. 31.3.1950. 11. IS.3.1950. Lead bearing material on concrete. Close-up of 10. background, earlier date. 10, 11 and 12 are intermittent. gf 00-1005! 12. 31.8.1950. Heavy deposit, -4- 13. 11.8.50. 14. Eack flooding of chemical drains. Intermittent. 11.8.50. Farmyard. 15. 11.8.1950. Contaminated water in 13 and 14 flowing through opening in fence into ditch', in Moss Lane. aSS***^*: 16. March, 1950. C\2 17. 3.8.1950. Incomplete! incinerated material, some of which is lead bearing. Field beyond is the one in which the animals died. j^j=~ 001005 13. 11.3.50 14. Back flooding of chemical drains. Intermittent. 11.3.50 Farmyard. 15. 11.3.1950. Contaminated water in 13 and 14flowing through opening in fence into ditch'. in Moss Lane. 16. March, 1950. 17. 3.3.1950. Incompleted incinerated material, some of which is lead hearing. "beyond is the one in which the animals died. Field 18. 18.3.1950. 19. 3.8.1950. Incompletely incinerated organic lead bearing material at incinerator in farmyard. Open hearth burning of lead bearing material. Fumes from incinerator and hearth are at low level HE 0010053 lit 20. March, 1950. Trench for decontamination of large parts of equipment. Note deposition of rubbish by wind. Note rails in background. 21. 3.S.1950. Close-up of rails. Note deposition of lead bearing material. 22. March, 1950. Scrap metal. Rubbish in interstices on ground was blown there by wind. AH sources other than "B" Building chimney and bursting of autoclave discs are not by themselves of great importance. The degree of contamination of vegetation by a burst autoclave disc under the worst known conditions gave rise to contamination of the following order; Samples were provided about a week after the incident. Deposition on Cabbage after Burst of Autoclave Disc. ?8.11.1950. | 1 ! ; i Size of sample Mg. Pb on*14 sa.in. 14 sq. inches. of heavily contaminated leaf. Amount in water ) Soluble U3ed for washing) in water. off surface ) Insoluble 0.85 contamination. ) in water. 47.0 Mg per sq.in. 0.061 3.55 ' Soluble chloride as chlorine 0.5 mg. per sq. inch. 10.11.1950. | Cabbage leaf after washing, i 14 sq. ins. Wt. 3.2 gms. Mg.Fb/14 | Mg.Pb/ % wt. p.p.m. sq. in. i sq. in. 4*4 ` 0.314 0.14 1400 140 i Hoo ? j Leaf of whole | ^ cabbage. MS 100100 5.4 . -; - 20. March, 1950. Trench for decontamination of large parts of equipment. Note deposition of rubbish by wind. Note rails in background. , 21. 3.8.1950. Close-up of rails. Note deposition of lead bearing material. 22. March, 1950. Scrap metal. Rubbish in interstices on ground was blown there by wind, AIL sources other than "Bn Building chimney And bursting of autoclave discs are not by themselves of great importance. The degree of contamination of vegetation by a burst autoclave disc under the worst known conditions gave rise to contamination of the following order: Samples were provided about a week after the incident. Deposition on Cabbage after Burst of Autoclave Disc. * 8.11.1950. Size of sample Mg. Pb on+14 sq.in. 14 sq. inches. of heavily contaminated leaf. Amount in water ) Soluble used for washing) in water. 0.85 off surface ) Insoluble contamination. ) in water. 47.0 Hg per sq.in. 0.061 3.55 j Soluble chloride as chlorine 0.5 mg. per sq. inch. ; 10.11.1950* 1 ! Cabbage leaf : after washing, j 14 sq. ins. j Wt, 3.2 gms. j Leaf of whole j cabbage, j 14 sq. ins. 1 Wt. 3.8 gms. y... ------------- ------ ------------ --1 Mg.Fb/14 | Mg.Pb/ sq. in. i sq. in. i % wt. p.p.m. Mg./lOO gm. ' 4*4 0.314 0.14 1400 140 ! 1 * 3.8 0.271 0.15 1500 150 The photographs are not intended to indicate present conditions. A proper incinerator has been located elsewhere, and the farmyard is little used at the present time. Kg' 0010055 L 6- - Table 3 shows the degree of contamination of vegetation over a period of years. The figures for 1949 are excluded as the method of analysis was inaccurate. Notes. 1. All samples were collected by the Management 1942 - 1950, with the exception of one water sample, (Point 5) which was taken by the Medical Department on 30.11.50. - Result, 0.29 p.p.m. The vegetation analyses 1942 - 1947 inclusive were done in the Research Laboratories, I.C.I., Winnington. In 1948 and 1949 the Courtauld Institute methods were used. In 1950 the Bambach and Burkey method was used by us. Water samples have been done by the Northwich plant works laboratory with the exception noted. 2. Location of animals - see map. Febrnaly t0 end of August Grey horse ) Mare and foal ) A.B.C. Late August - November. Late September - November. Mare and foal. ) Grey horse. ) D.E. November, for four days. All three animals. F. November, seven days approximately before death. All three animals. G. kE" 001005G 5th January, 1951? j'iiZ HAftmFUu EFFECTS OF LEAD OK ANLdALS. Heview. In the early part of the nineteenth century, it t o s not uncommon for cattle, grazing on the hillaide-s in part of Co. Durham, to die from .a disease attributed to lead, which had been deposited on the herbage from the chimneys connected with local lead-smelting furnaces. In the early thirties of this century, similar deaths of livestock occurred in various districts of the same county, but all had the common factor in the presence of coke ovens adjacent to the grazing grounds implicated. Dunn and Bloxham (1, a and b) found lead (14 p.p.m.) and copper (4.7 p.p.m.) in herbage in one such area. One farmer lost about thirty animals which had grazed on such contaminated pastures, and had others ill. The water supply for the livestock was not involved.- Lead was found in the organs of some poisoned animals to the concentrations: Liver Kidney. Stomach tissue 2.6 p.p.m. 1.7. p.p.m. 0.6 p.p.m. Pyrites in coal may contain lead in varying proportions from 20 toJO p.p.m., and it wa3 inferred that this was the source of the contamination of the vegetation. In continental countries and America, the problem of lead absorption in animals has been investigated from time to time, and some of the more recent work is included in this short review, although the value is not great for purposes of comparison with the problem at the manufacturing plant in ISorthmich. Gabel (2) considered subacute lead poisoning a frequent disease in veterinary practice, and found the concentration of lead in liver tissue a useful guide when considered critically. He presumed lead could have been fnt. ubtnoo Of-horn, or oo. KE 001005 In hio oxperisnco tho t--.i-' --- -- - - for cattle, grazing on the hillsides in part of Go. Durham, to die from.a disease attributed to lead, which had been deposited on the herbage from the chimneys connected with local lead-smelting furnaces. In the early thirties of this century, similar deaths of livestock occurred in various districts of the same county, but all had the common factor in the presence of coke ovens adjacent to the grazing grounds implicated. Dunn and Bloxham (1, a and b) found lead (14 p.p.m.) and copper (4.7 p.p.m.) in herbage in one such area. One farmer lost about thirty animals which had grazed on such contaminated pastures, and .had others ill. The water supply for the livestock was not involved. Lead was found in the organs of some poisoned animals to the concentrations: Liver Kidney. Stomach tissue 2.6 p.p.m. 1.7. p.p.m. 0.6 p.p.m. pyrites in coal may contain lead in varying proportions from 20 toyO p.p.m., and it was inferred that this vns the source of the contamination of the vegetation. In continental countries and America, the problem of lead absorption in animals has been investigated from time to time, and some of the more recent work is included in this short review, although the value is not great for purposes of comparison with the problem at the manufacturing plant in I'i orthwich. Gabel (2) considered subacute, lead poisoning a frequent disease in veterinary practice, and found the concentration of lead in liver tissue a useful guide when considered critically. He presumed lead could have been dangerous to.; life when, "the lead vas' in'exoess of 0.2 rug. per lOO gms. of liver A substance of horse or cow. .In his experience the incidence of the ill effects of lead varied with the season. Xt increased gradually during the summer, fell during the autumn, rose again in November and fell to a low level throughout the winter. He considered inhalation of lead-bearing dusts as contributing to the lead absorption of animals. Not all the observations made by this writer conform to the current; consensus of opinion on lead metabolism . v/ayrauch and blacks (3) found that lead absorption increased - KE 0010058 2- - with the feeding of green food. Dankwortt and Roll (4) determined the lead content of cows, pig's and horses, which had been slaughtered in the municipal abattoir in Hanover, and also from material obtained in the open market. Three analytical pro cedures were used, including the electrolytic method of Schmidt and Weyrauch (5) > whose work is considered subsequently. They considered the quantitative determination of lead with dithizone by the Fischer method unsatisfactory, as its accuracy is disturbed by organic material. Their findings by the electrolytic method used were:- Tissue. Liver Kidney Spleen Brain Bone Concentration. Mg. Pb/100 gm. 0.02 0.015 0.015 0.015 0.07 ..*.P *iS1 .2 15 15 15 7 Other investigators have had difficulty in finding any lead in brain, especially of smaller animals such as the rabbit, even when these had been given lead by various routes for significant periods. In summarising their findings, Dan'ckwortt and Holl (4) state that in cows, values of o.Ql - 0.1 mg. Pb per 100 gm. of an organ is normal. In bones of cows, lead in concentrations of 1.1 mg. per 100 gm. is normal. The mean value of liver, kidney and spleen is 0.025 mg- per 100 gm. and 0.66 mg. for bone substance. In jogs the mean value for organic concentrations of lead is six times more than in cows, and for bones the concentration i3 double. This is probably due to a greater ingestion of lead by the omniverous pig than by the herbiverous cow. Weyrauch and Muller (6) state that allowance should b mad for -the state of ths tissue being analysed, being approximately four times the dry weight. the fresh weight *"* ' * ~J ~ A T *%'* ^ rt Vi.rtrn+T nn nrtv be best 0010059 cedures were used, including the electrolytic method of Schmidt and Weyrauch (5) > whose work is considered subsequently. They considered the quantitative determination of lead with dithizone by the Fischer method unsatisfactory, as its accuracy is disturbed by organic material. Their findings by the . electrolytic method used were:- Tissue. Liver Kidney Spleen Brain Bona G oneentration. Mg. Pi/100 gm. 0.02 0.015 0.015 0.015 0.07 Ppm< .2 .15 15 15 7 Other investigators have had difficulty in finding any lead in brain, especially of smaller animals such as the rabbit, even when these had been: given lead by various routes for significant periods. In summarising their findings, Danckwortt and Holl (4) state that in cows, values of o.Ql - 0.1 mg. Pb per 100 gm. of an organ is normal. In bones of cows, lead in concentrations of 1.1 mg. per 100 ga. is normal. The aean value of liver, kidney and spleen is 0.025 mg* per 100 gm. and 0.66 mg. for bone substance. In pig3 the mean value for organic concentrations of lead is six times more than in cows, and -6r bones the concentration i3 double. This is probably due to a greater ingestion of lead by the omniverous pig than by the herbiverous cow. Weyrauch and duller (6) state that allowance should be made for the state of the tissue being analysed, the fresh weight being approximately four times the dry weight. Pfrieme (7) considers that increase in lead absorption may be best determined from cone analysis, and next in the liver and kidneys. Traces are present also in the qpleen, out the brain was always found lead free, lie determined particularly the lead content of teeth, which should be relative to that of bone. Human and animal teeth fromnany sources were analysed. He found le-.d in the teeth of normal individuals, and found more in individuals HE 0010060 i -3- of older age groups. Lead is normally present in the teeth of carnivora, and herbivora, less in the latter. An omniverous animal, the pig, holds an intermediate position. The maximum normal concentration found in horse teeth was 0.04 mg. per 3 gm* of ash. Other investigators have found lead in higher and lower concentrations than in bone. The consensus of opinion appears to be that greater concentrations are to be fcund in teeth, and in the greatest concentration in the dentine of the teeth roots. In man, accumulation of lead in teeth as great as 7*9 mg. per 100 gm. ash has been found. '.Yeyrauc'n (3) considers that lead is present essentially in the bones, kidneys, liver and blood. He is also of the opinion of Barth (9) and morris (10) that the lead value in bone increases with age, but does not run parallel to the age. Lehmann (11) found the goat relatively resistant to lead, and iYeyrauch (8) has confirmed this. In the experiments of Lehmann, a goat was fed with 0.6 gm. of lead chromate daily for 91 days, without apparent ill effect. Weyrauch fed a goat with 180 gm. of lead acetate with 280 gm. of white lead, i.e. 33^ gm. of lead over a period of ten months. The animal remained in good' health and gained weight. On analysis of some ti3iues after slaughtering, considerable quantities of lead were found, especially in the bones, kidney, liver, brain, spleen and pancreas. Goat. Hfc. Pb/lOO gm. dry tissue. Liver Kidney Cortex medulla Lung Spleen Long bone Brain 1.4 4.1 1.7 0 0.53 13.8 O.95 P. o.m 14 41 17 0 5-3 138 9*5 Am -V*rihe di8tribution of ftj? O.QlOubl in a calf and a rnxre wuose decease was o c b i/u was w .'j h - mg. per j gm. u j . tt.su. uonar xnveaT.igax.or3 nave xouna xeaa in higher and. lower concentrations than in bone. The consensus of opinion appears to be that greater concentrations are to be found in teeth, and in the greatest concentration in the dentine of the teeth roots. In man, accumulation of lead in teeth as great as 7*9 "S* Pr 100 gm* ash has been found. Weyrauch (8) considers that lead is present essentially in the bones, kidneys, liver and blood. He is also of the opinion of Barth (9) and Morris (10) that the lead value in bone increases with age, but does not run parallel to the age. Lehmann (11) found the goat relatively resistant to lead, and Weyrauch (8) ba3 confirmed this. In the experiments of Lehmann, a goat ms fed with 0.6 gm. of lead chromate daily for 91 Hays, without apparent ill effect. Weyrauch fed a goat with 180 gm. of lead acetate with 80 gm. of white lead, i.e. 330 gm. of lead over a period of ten months. The animal remained in good health and gained weight. On analysis of some tissues after slaughtering, considerable quantities of lead were found, especially in the bones, kidney, liver, brain, spleen and pancreas. Goat. Hr-e. Pb/100 gm. dry tissue. Liver Kidney Gortex Medulla Lung Spleen Long bone Brain 1.4 4.1 1-7 0 0.53 13.8 o.95 14 41 17 0 50 . - 138 9*5 ~ ' r r*.*.. i - . ' ` " si'-U The distribution of lend in a calf and a mre whose decease was attributed to lead are shown in the following table. The immediate cause of death in the mare was apparently pneumonia, and the source of lead, dust from a foundry.' He 0010062 Table 1 SOLUBILITIES IH WATER OF LEAD QOEPCUMBS. The 1950 edition of Perry's Chemical Engineers' Handbook gives the following figures in gms./l90 gm, water. Temperature G. 9 18 20 Lead acetate. Lead bromide. Lead,carbonate. . Lead chloride. Lead sulphate. Lead sulphide.' Lead Monoxide. ' 55-04 0.4554 0.85 0.00011 0.6728 0.0028 0.0035 0.99 0.0041 0.00009 0.0068 HO O u-\ <M 1 30 1.15 1.20 0.0049 KE 001006,V -4- Tissue. -- Liver Kidney Lung Spleen Bone Blood Intestine (with contents) lag. Pb per ICO gm. dry tissue. Calf. Mare. Normal Horse. 5.0 27.0 1.4 2.4 7-7 1.0 7.8 1.5 7.0 -- 2.5 4.0 0.13 Trace 0 0 0.5 0 Should these results be used for comparison vith our investigations diown subsequently^allowance should be made for the possibly greater accuracy of the method used by us, and also for the fact that our results are calculated on the weight of fresh tissue, which is stated above to be four times as heavy as dry tissue. The method used by Weyrauch is probably not very inaccurate, which would permit the inference that, for purposes cf comparison, our figures are low. Weyrauch states that in human and animal lead poisoning, it is necessary to examine the liver, kidney, spleen, brain, bone and blood. In children and young animals, there is good evidence that lead is deposited in the growing ends of bones in a selective manner. X-ray examinations have shown areas of increased density which in long bones appear as a series of transverse lines in the diaphysis (end of shaft) -immediately below the epiphysis (growing end). The relative toxicity of lead and lead compounds requires consideration as well as the distribution of leadin tissues, which has occupied most attention in tiiis review. Fairhall and Sayers (12), from their experiments with guinea pigs, consider lead arsenate, carbonate, monoxide and sulphate to be more toxic than lead and other lead compounds when fed to animals, possibly due -to -their greater solubility in digestive juioea. The solubilities of various lead compounds are shown oh table 1, which was prepared by W.T. Barium from recant literature. Pai rhall and Sayers found lead in 0010064 f-* * Bone Blood Intest ine (with contents) 17*.07 7.8 42.00 0.13 0 oo 0 Should these results be used for comparison mth our investigations diown subsequently^allowance should be made for the possibly greater accuracy of the method used by us, and also for the fact that our results are calculated on the weight of fresh tissue, which is stated above to be four times as heavy as dry tissue. The method used by Weyrauch is probably not very inaccurate, which would permit the inference that, for purposes cf comparison, our figures are low. iVeyrauch states that in human and animal lead poisoning, it is necessary to examine the liver, kidney, spleen, brain, bone and blood. In children and young animals, there is good evidence that lead is deposited in the growing ends of bones in a selective manner. X-ray examinations have shown areas of increased density which in long bones appear as a series of transverse lines in the diaphysis (end of shaft) .immediately belovT the epiphysis (growing end). The relative toxicity of lead and lead compounds requires consideration as well as the distribution of leadin tissues, which has occupied most attention in this review. Pairhall and Sayers (12), from their experiments with guinea pigs, consider lead arsenate, carbonate, monoxide and sulphate to be more toxic than lead and other lead compounds when "fed to animals, possibly due to their greater solubility in digestive juices. The solubilities of various lead compounds are 3hown on table 1, which was prepared by Dr. W.T. Sarlam from recent literature. Pairhall and Sayers found lead in the liver, . .^re in the nidney, and most an the bone, in an approximate ratio ^*3*/ afterin^estion. After inhalation of lead only the liver kidney bone ratio was approximately 1:2.5si.8. In another experiment in which a dog was fed large quantities of lead the liver kidney bone ratio was 1:2.51.8. 0010065 Consideration of the report of the Selby Smelter Commission has purposely been, left to this stage. It should be appreciated that this admirable report was published in 191p> since which time the methods of analysis have greatly improved, and knowledge of lead from the medical point of view has made great advances. In fact, the entire problem of lead metabolism in the animal organism has been established in a very different light. The following points from the report are of interest. The amount of lead found in grass after a dry summer was 21 p.p.m. (maximum), which amounted to 0.9 gm. Pb per 100 lbs. of hay. There was no evidence that this degree of contamination, or that the ingestion of 0.25 f lead per day by a horse would result in symptoms of chronic lead poisoning. The rate of discharge of lead fume up the chimney after passing through a bag filter was 96 - 113 lbs. in 24 hours. They considered that the amount of lead deposited on soil was so small that it would take raany years to bring about an appreciable increase in the lead content of soil. It was estimated that lead would require to be present in a concentration of about 1200 part3 per million before it would interfere with the growth of vegetation. The mean concentration on exposed surface soil in "the smoke zone was 15*2 p.p.m. In the livestock survey, injury to horses is noted. No injury to cows, pigs and sheep i3 noted. Horses develop a paralysis of the throat muscles in chronic lead poisoning, and are more liable to pneumonia, possibly due to innaluvion of food particles into the lungs owing to the paralysed condition# Lead i3 present, in the milk of human and animal females, and is incroaaeci under conditions of excessive lead absorption and lead poisoning. The contamination of foodstuffs by lead deserves mention wnere relevant to this review. The lead in water in the Northwich area is about 05,93.,,Pv- 1-fc is considered, by some authorities that potatoes and other , - much ot tho load In this country, 0.3 p.p.m. of load in water is considered safe. point of view has made great advances. In fact, the entire problem of lead metabolism in the animal organism ha3 been established in a very different light. The following points from the report are of interest. The amount of lead found in gras3 after a dry summer was 21 p.p.m. (maximum), which amounted to O.9 gm. pb per 100 lbs. of hay. There was no evidence that this degree of contamination, or that the ingestion of 0.25 of lead per day by a horse would result in symptoms of chronic lead poisoning. The rate of discharge of lead fume up the chimney after passing through a bag filter wa3 96 - 113 lbs. in 24 hours. They considered that the amount of lead deposited on soil was 30 small that it would take many years to bring about an appreciable increase in the lead'content of soil. It was estimated that lead would require to be present in a concentration of about 1200 parts per million before it would interfere with the growth of vegetation. The mean concentration on exposed surface soil in the smoke zone was 15*2 p.p.m. q In the livestock survey, injury to horses is noted. No injury to cows, pigs and sheep is noted. Horses develop a paralysis of the throat muscles in chronic lead poisoning, and are more liable to pneumonia, possibly due to inhalation of food particles into the lungs owing to the paralysed condition. Lead is present in the milk of human and animal females, and is increased under conditions of excessive lead absorption and lead poisoning. The contamination of foodstuffs by lead deserves mention where relevant to this review. The lead in water in the Northwich area is about 0.03 p.p.m. It is considered by some authorities that potatoes and other vegetables, when boiled in water containing lead, take up much of the lead present. In this country, 0.3 p.p.m. of lead in water is considered safe, O.5 p.p.m. is the maximum permissible concentration, and 0.7 p.p.m. i3 dangerous. Kehoe holds that 0.1 p.p.m. is the maximum permissible for potacle water. Most human foodstuffs contain less than 1 p.p.m., although some one, two or more p.p.m. No general regulation governs the amount permissible in foodstuffs, but the general opinion i3 that it should be kept 001006T 6- - out of food as nuch a3 possible, and should not exceed 2 p.p.m. in most instances. Under regulation, the maximal amount of lead permissible in edible gelatine is 10 p.p.m. The Pood and Drug3 Act, 1933> gives a blanket cover in prohibiting the addition of injurious substances to food. Lead arsenate is used as an agricultural insecticide. The present United States limit i3 ~j.Z p.p.m. It would appear that the natural, lead content of wheat may be higher than was previously thought. Kent (14) found 0.9 p.p.m. in wheat flour, and 3 p.p.m. in the bran. The pericarp of wheat contained as much as 4.8 p.p.m. Load Metabolism, A vast amount of -work on lead metabolism, normal and abnormal, has been and continues to be published. Most of this is not directly applicable to the problem presently to be discussed, and our basis for this purpose is now given succinctly. The earth is a lead-bearing planet, and therefore small quantities of lead are found normally in the soil, the flora that flourishes in this, the water draining it and the fauna which drink and feed on these, and in some cases on themselves. Lead does not play an essential part in the metabolism of vegetation, only minute amounts are to be found in the protoplasm. Successive amounts of lead in vegetation are due to deposits on the surface through man made agencies, and such lead bearing material may adhere so firmly to vegetation that it may be considered part of the vegetation. Wind and rain my remove some of the deposited lead, but in most cases the reduction in concentration per unit of surface will not be sufficient to reduce to any material extent the superimposed lead. Under normal conditions, all men and animals absorb most of the lead for their tissues from food and drink ingested. Under circumstances in which there is excessive exposure to lead, man usually inhales it, his food sources remaining normal, but in animal's the main portal of entry remains the .alimentary tract, as the source of lead is usually contaminated vegetation, - and consequently animals most dependent upon this for nutrition, such as the herbivora, are likely to absorb most, although herbivora normally ingest and absorb least lead. No definite statement can be made on the relative susceptioility of animals. There may possibly be no such condition as relative susceptibility to lead poisoning. The result may depend upon the dose ingested and absorbed relative to the body weight, with due consideration of other possible variants, such as growth, age, of lead HE 0010069 storage and rates of excretion now given succinctly. The earth is a lead-bearing planet, and therefore small quantities of lead are found normally in the soil, the flora that flourishes in this, the water draining it and the fauna which drink and feed on these, and in some cases on themselves. Lead does not play an essential part in the metabolism of vegetation, only minute amounts are to be found in the protoplasm, lixcessive amounts of lead in vegetation are due to deposits on the surface through man made agencies, and such lead bearing material may adhere so firmly to vegetation that it may be considered part of the vegetation. Wind and rain may remove seme of the deposited lead, but in most cases the reduction in concentration per unit of surface will not be sufficient to reduce to any material extent the superimposed lead. Under normal conditions, all men and animals absorb most of the lead for their tissues from food and drink ingested. Under circumstances in which there is excessive exposure to lead, man usually inhales it, his food sources remaining normal, but in animals the main portal of entry remains the alimentary tract, as the source of lead is usually contaminated vegetation, and consequently animals most dependent upon this for nutrition, such as the herbivora, are likely to absorb most, although herbivora normally ingest and absorb least lead. No definite statement can be made on the relative susceptibility of animals. There may'possibly be no such condition as relative susceptibility to lead poisoning. The result may depend upon the dose ingested and absorbed relative to the body weight, with due consideration of other possible variants, such as growth, age, storage and rates of excretion of lead. In animals, it is considered that most lead is absorbed into the portal blood stream from the alimentary tract, and carried by that system to the liver, which acts as a filter, barrier, and temporary store. The portal blood flow 'kQ looked upon a3 passing through the liver, and connecting the intestine to that organ. Prom the liver, it will pass into the systemic circulation, and ftr 0010070 8- - be carried to all tissues in that vehicle. The liver may pass a little via the bile back into the alimentary canal. The kidneys, being the main filter, will excrete the lead carried to them in the blood as a non-essential and inert substance. The amount found in the liver depends upon the quantity of lead ingested daily, and the period over which this dose is ingested. If large amounts are taken consistently, then the liver concentration will be high compared with other tissues. An exchange between the blood and tissues is a t continuous process, and most will be pasaed from the former to bone for permanent storage. ' It may .be anticipated that more will be stored in the more dense bone And at the growing end. In the presence of intense or high constant absorption, the power of excretion of the kidneys and rate of storage in bone may be incapable of keeping the concentration in blood and the tissues within a reasonaole level, with the inevitable result that signs of intoxication will arise from the protoplasmic poison - lead. The Present Problem. The foregoing notes, we feel, present succinctly current views and findings on normal and abnormal lead metabolism in animals. i.. Three horses x' died over a short period near the Northwich plant, and it was suggested by the local farmer that these animals might possibly have died as a result of lead poisoning. Our findings are presented in chronological form. JN. O O The owner of the three animals, the tenant of Langford Farm, stated T-t o that he purchased the grey horse or gelding at a fair in Wrexham in either o January of February of last year. The mare, which was about five years old, was bought in foal from a farmer in the Mobberley area, which is about seven miles or so from the plant. The colt was born in Langford Farm in May. The gelding was worked intermittently and had additional feeding with purchased bran and chopped-up hay, which had been grown locally. All three animals had -rt -fS ex*! ^ o n vs fV.rs T^ tv . '- ' * amounts are taken consistently, then the liver concentration will be high compared with other tissues. An exchange between the blood and tissues is a continuous process, and most v/ill be passed from the former to bone for permanent storage. It may .be anticipated that more will be stored in the more dense bone and at the growing .end. In the presence of intense.or high constant absorption, the power of excretion of the kidneys arid rate of storage in bone may be incapable of keeping the concentration in blood and the tissues within a reasonable level, with the inevitable result that signs of intoxication will arise from the protoplasmic poison - lead. The Present Problem. The foregoing notes, we feel, present succinctly current views and/ findings on normal and abnormal lead metabolism in animals. / .. Three horses * died over a short period near the Northwich plant, and it was suggested by the local farmer that these animals might possibly have died as a result of lead poisoning. Our findings are presented in chronological form. The owner of the three animals, the tenant of Langford Farm, stated that he purchased the grey horse or gelding at a fair in Wrexham in either January of February of last year. The mare, which was about five years old, was bought in foal from a farmer in the Mobberley area, which is about seven miles or so from the plant. The colt was born__in-Langford Farm in May. The gelding was worked intermittently and had additional feeding with purchased bran and chopped-up hay, which bad been grown locally. All three animals had been in fields in the vicinity of Langford Farm until about the end of August, 1950* Tiis water supply of these fields is through an I.C.I. pipe line, the source of the water being Cranage Brook. The water is, in all cases, delivered into a trough. About the end of August, the mare and the foal were put to graze in two fields, one field North and the other North-East,of the plant. These fields had had cereal crops on them, and the grass was short x One of these was shot. 0010072 . -9_ ana new. Cows also grazed on these fields. There are a few surface collections of water on these fields. The main water supply for the horses and cattle is a trough, which fills from the town main supply. About a month later, that is aoout the end- of September, the gelding was also put into this field, and thereafter its movements -were similar to those of the mare and colt foal. All three remained in these two fields until some time in November, when they were removed some distance away, to a field South-Bast of the plant, the v/ater supply of which was two ponds, supplied by surface water. They remained here for approximately four days. Someone is stated to have left the gate of this field open, and the horses found their my on to Moss Lane, and were found the following morning near the plant, and were placed in a field immediately Bast of the plant, in which bralam farmstead is situated. This field had also had cereal crops. There are five ponds in this field, all filling from surface water, and one of these is adjacent to Moss Lane at the level of "G" Building. The others are approximately 200 yeard from the plant. About a week later, the foal was found dead, and the mare was stated to be missing. This was on the morning of Tuesday, 28th November. On the morning of the 29th November one attended a post mortem on the colt, with the Veterinary Surgeon, Mr. W. V/ilson, The Willows, Hartford, Northwich.. - The immediate cause of the death of the foal colt was obviously a massive pneumonic consolidation of the lungs, which mist have commenced some days before death. There was a slight excess of free fluid in the abdominal cavity. , Pneumonia in colts was stated to be very rare in this area. The colt was also stated to be in good condition. Samples of various tissues of this animal were taken. The same afternoon, the Veterinary Surgeon informed us that the mare had been found dead in the same field, and that the gelding was in a dying condition, and passing- mucus in its ptools. The post mortem of these two animals was attended by the Veterinary Surgeon and us tho following morning, on which the gelding had been shot. 'The post mortems in all cases were performed at the yard of and thereafter its movements were similar to those of the ,are and colt foal. All three remained in these two fields until some time in November, when they were removed some distance avray, to a field South-Mast of the plant, the water supply of which was two ponds, supplied by surface water. They remained here for approximately four days. Someone is stated to have left the gate of this field open, and the horses found their way on to Moss Lane, and were found the following morning near the plant, and were placed in a field immediately-East of the plant, in which G-ralam farmstead i3 situated. This field had also had cereal crops. There are five ponds in this field, all filling from surface water, and one of these is adjacent to Moss Lane at the level of "G-" Building. The others are approximately 200 yeard from the plant. About a week later, the foal was found dead, and the mre wa3 stated to be missing. This was on the morning of Tuesday, 28th November. On the morning- of the 29th November one attended a post mortem on the colt, with the Veterinary Surgeon, Mr. ,7. Y/ilson, The Willows, Hartford, Northwich. The immediate cause of the death of the foal colt was obviously a massive pneumonic consolidation of the lungs, which must have commenced some days before death. There was a slight excess of free fluid in the aodominal cavity. Pneumonia in colts was stated to be very rare in this area. The colt was also stated to be in good condition. Samples of various tissues of this animal ?/ere taken. The same afternoon, the Veterinary Surgeon informed us that the mare had been found dead in the same field, and that the gelding was in a dying- condition, and passing mucus in its stools. The post mortem of these two animals was attended by the Veterinary Surgeon and us the following morning, on which the gelding had been shot. The post marteras in all cases were performed at the yard of Messrs. Warburton. Licensed Slaughterers, Moss Lane, Altrincham. The. mare was in an advanced state of decomposition, and had been, in our opinion, dead for some time, and it is most likely that it had died before the colt. The gelding had a small patch of pneumonia at the apex of one lung, which the Veterinary Surgeon stated was insufficient to cause the illness from which the KF 0010074 SO > O o *--/ o o Vii animal m3 suffering-. Samples were also taken from these two animals, and also from another horse from a farm in Little Leigh, about five miles from the plant. This latter had been shot on account of a septic arthritis. The Veterinary Surgeon obtained duplicate samples of the tissues of the gelding or grey horse. All samples of tissue were 3een to come' from the animals in question, with the exception of the sample of bone from the mare, and a limb stated to belong to thisanimal was taken from a bin, and a sample of bone taken from it. Itwas not possible to obtain samples of urine from these animals, as the bladders'were empty. The blood samples were obtained from the heart, and consisted of blood clot, which ms similar in condition in the two samples taken. The results of the analysis of these samples are shown in table 2. Further samples are being obtained and analysed to complete the control animal. The farmer stated on the 29th December that he had had no cows or other animals ill with any condition similar to that from -which the gelding suffered. The farmer deals in horse3 as a side line, and it was his opinion that adult animals would eat about 40 pounds of graws per day. The foal coif, he felt, would be suckled by its mother until about a year old, and as it was only seven months at the time of death, he felt that it would not be eating much grass. The Veterinary Surgeon's opinion on this is that the colt foal would eat grass to supplement its diet of milk, which would be failing in the mare at this time of the year. A sample of water from the pond in the field East of the plant, near * "(x* Building, was obtained on the JOth December, and contained .29 parts of lead per million. Samples of grass from some fields round the plant were ootained on the 30th November. In the fields Worth and Harth-JSast of the plant the lead concentrations were 1181 and 1921 part3 of lead per million, and in the field East of the plant 1348 and 135 parts of lead per million. All these samples were collected by the Works Management, and we had no knowledge of the locations from which they were collected during analysis. In cases of reputed lead ...oisoning, it is necessary to establish 1 A ror grey horse* All samples of "tissue were seen to come from tho animals in question, with the exception of the sample ci bone from the mare, and a limb stated to belong to thi3 animal was taken from a bin, and a sample of bone taken from it. It was not possible to obtain samples of urine from these animals, as the bladders were empty. The blood samples were obtained from the heart, and consisted of blood clot, which was similar in condition in the two samples taken. The results of the. analysis of these samples are shown in table 2. Further samples are being obtained and analysed to complete the control animal. The farmer stated on the '29th December that he had had no 00W3 or other animals ill with any condition similar to that from which the gelding suffered. The farmer deals in horses as a side line, and it was his opinion that adult animals would eat about 40 pounds of grans per day. The foal colt, he felt, would be suckled by its mother until about a year old, and as ' it was only seven months at the time of death, he felt that it would not be eating much grass. The Veterinary Surgeon's opinion on this i3 that the colt foal would eat grass to supplement it3 diet of milk, which would be failing in the mare at this time of the year. A sample of water from the pond in the field Hast of the plant, near x "G" Building, ms obtained on the 3^th December, and contained .29 parts of lead per million. Samples of grass from some fields round the plant were ootained on the JOth "November. In the fields Forth and Forth-East of the plant the lead concentrations were 1181 and 1921 parts of lead per million, and in the field East of the plant 1348 and 13JO parts of lead per million. All these samples were collected by the Works management, and we had no knowledge of -the locations from which they were collected during analysis. In cases of reputed lead poisoning^ it is necessary to establish (1) that there has been significant exposure to lead, (2) that the symptoms and signs are those of lead poisoning, (3) that the tissues or other biological samples contain lead in concentrations greater than normal, when analysed by a x Point 5 on map He 0010076 -11- precise technique, with all due precautions and allowances being made for the possibility of contamination, and (4) that there is no other evident cause for the condition. Prom the foregoing, it is obvious that the first condition is present, namely contamination of pasture by lead to a vary considerable degree. The condition of the animals prior to death is not known, but what little is known of the gelding does conform, to what may be? anticipated in lead poisoning in horses. Some tissues of the animals had contained high concentrations of lead, and there is no evident cause of death other than the pneumonic conditions in the lungs of the colt and the gelding, which are considered to be due to intercurrent disease, which has been previously described a3 associated with lead poisoning in horses. Consideration of the figures on table 2 shown a high concentration of lead in the liver of the foal, mare and grey horse compared with the control animal, and at a higher ratio than that found in the results for the kidney and bone. This, interpreted by us, means that there was very intensive and possibly prolonged absorption of lead from the alimentary tract prior to death. The kdd.ney concentrations of lead are sufficiently high to warrant the conclusion that these animals were excreting.lead via the kidneys in some considerable concentration. The findings in the bone of the colt indicate that this, animal had been absorbing lead for some considerable time before death, and the concentration of lead in the colon contents of this animal, which to us seemed to consist of a grassy--looking material, when expressed either per 100 grammes of the sample or in terms of the ash, is also beyond normal limits. The bones of the mare and gelding contain lead in concentrations slightly in excess of normal. Nevertheless, we feel that these animals also had been ingesting lead bearing material for some considerable period before death. -"The main source of the lead bearing material in the adult animals 00100 2 * present, namely contamination of pasture by lead to a very considerable degree. The condition of the animals prior to death is not known, but what little is known of the gelding does conform to what may be anticipated in lead poisoning in horses. Some tissues of the animals had contained high concentrations of lead, and there is no evident cause of death other than the pneumonic conditions in the lungs of the colt and the gelding, which are considered to be due to intercurrent disease, which has been previously described as associated with lead poisoning in horses. Consideration of the figures on tabid 2 shown a high concentration of lead in the liver of the foal, mare and grey horse compared with the control animal, and at a higher ratio than that found in the results for the kidney and bone. This, interpreted by us, means that there was very intensive and possibly prolonged absorption of lead from the alimentary tract prior to death. The kidney concentrations of lead are sufficiently high to warrant the conclusion that these animals were excreting lead via the kidneys in some considerable concentration. The findings in the bone of the colt indicate that this.animal had been absorbing lead for some considerable time before death, and the concentration of lead in the colon contents of this animal, which to us seemed to consist of a gras sy-l ooking material, when., expressed either .per 100 grammes of the sample or in terms of the ash, is also beyond normal limits. The bones of the mare and geidlng contain lead in concentrations slightly in excess of normal. Nevertheless, we feel that these animals also had been ingesting lead bearing material for some considerable period before death. The main source of the lead bearing material in the adult, animals is, in our opinion, the vegetation consumed. The amount contained in water compared 'with this is insignificant. The amounts found in water in the fields in the area are shown on the table overleaf, and of these points, 4 and 5 relate to the fields on the. East of the plant, and 1,2 .and 3 to the fields on the North and North-Saat. t< 0010078 -12- The possibility of the inhalation of lead cannot be excluded, as frequently the smoke, fume, dust and mist from chimney -wastes and inorganic lead vapours my cross the fields in which the horses have grazed at the level of the breathing zone of animals. It is understood that on the night of the 27th November or early morning of the 28th November, a considerable amount of organic lead was liberated to the atmosphere from an autoclave, and that no tetraethyl lead ms obtained from the reaction mass remaining afterwards. There is the remote possibility that this may have had some detrimental effect' on the gelding, but at the time of this occurrence, it is cur opinion that the colt was already dying, and the mare already dead. The pneumonia in'the colt at this time was, in our opinion, already advanced, and parts of the lung solid. The inhalation factor is, in our opinion, insignificant compared with tiiat of ingestion of lead deposited on vegetation. We are not prepared to say definitely that the lead on the vegetation was due to either inorganic "or organic lead, but we do feel that the evidence points to inorganic lead being the most likely form in which the deposition occurred. It is not inferred, from the concentrations of lead found on the grass after the event, that such or more concentrations existed for the some eighty day^on. which these animals grazed on these fields. In parts, the lead concentration"was probably much less than that found, particularly after the crops had been removed. On the other hand, consideration- of the findings indicate to us that it was very probable that a short time prior to death these animals had ingested vegetation containing lead at a much greater concentration than the findings for vegetation indicate. It is not known, and can never now be determined, whether or not these animals ingested lead from the grass on the roadside on iIos3 Lane in the vicinity of the plant on the night on which they escaiei from the field near Langford Faria. Tnis area has been at times heavily contaminated by lead bearing materials, and no doubt that part of the field adjacent to Moss Lane has, at times, contained high concentrations of lead. 0Q1QQ7U 2"/th November or early morning of the 28th November, a considerable, amount of organic lead ms lioerated to the atmosphere from an autoclave, and that no tetraethyl lead ms obtained from the reaction mass remaining afterwards. There is the remote possibility that this may have had 3ome detrimental effect on the gelding, but at the time of this occurrence, it is our opinion that the colt ms already dying, and the mare already dead. The pneumonia in the colt at this time ms, in our opinion, already advanced, and parts of the lung solid. The inhalation factor is, in our opinion, insignificant compared with that of ingestion of lead deposited on vegetation. We are not prepared to say definitely that the lead on the vegetation ms due to either inorganic or organic lead, but we do feel that the evidence points to inorganic lead being the most likely form in which the deposition occurred. It is not inferred, from the concentrations of lead found on the grass after the event, that such or more concentrations existed for the some eighty day^on which these animals grazed on these fields. In parts, the lead concentration was probably much less than that found, particularly after the crops had been removed. On the other hand, consideration of the findings indicate to us that it was very probable that a short time prior ..to death these animals had ingested vegetation containing lead at a much greater concentration than the findings for vegetation indicate. It is not. known, and can never now be determined, whether or not these animals ingested lead from the grass on the roadside on lloss Lane in the vicinity of the plant on the night on which they escaped from the field near Langford Farm. This area has been at times heavily contaminated by lead bearing materials, and no doubt that part of the field adjacent : to lloss Lane has, at times, containedhigh concentrations of lead. There are several ways in viiich the amount of lead ingested by the adult animals over the period may be approached, and from our hyperthetical calculations over the time at which the adult animals were exposed, we feel it is possible that they had ingested one half to one kilogramme, perhaps more, of lead searing material, in the vegstation consumed by them, and possibly of K& OOIOOSO -13this amount could be ingested from water. It is therefore our opinion that, whilst the evidence is not unequivocal, there is more than presumptive evidence to indicate that these animals suffered from lead poisoning, the possible sources of which are discussed in the subsequent section. KB 0010081 References. 1. Dunn, J.T. and Bloxham, K.G.L. (a) (1932). J.Soc. Chem.Med. 51:1001* (fa) (1933). J.Soc. Chan.lied. 52:1891. .2 Gabel, V/. (1940) . Naunyn-5chmiedebergs Arch. f. exper. Pathol, u. pharmakol., 195:383 3- Weyrauch, p. and Eecke A. (1933) Stschr. f. Hyg. u. Infektionskr., 114:629. 4. Danckwortt, p.VV. and Mill, K. (1934) Deut. Tierftrztl. Wschr. Vol. 42, 1934. 5- Schmidt, P. and 'Ygyrauch, p. (1933) "The Diagnosis of Lead poisoning in the light of modern research." G. Fischer, Jena. 6. Y/eyrauch, ?. and Hllller, h . (1931) Arch. f. Hyg., 114:46. 7- Pfrieme, p. (1934) Arch. f. Hyg., 111:232. .8 V/eyrauch, p. (1934) Ztschr. f. Kyg. u. Infektionskr., 116:28. 9* Barth, 3. (1931) Virchows Arch. f. path. Anat., Vol. 281, No* 1. .10 Morris, H.P. (1940) . Jn. of Ind. Hyg. and Tox. 22:100. .11 Lehmann, K.B. (1919) Handbook of Hygiene by Hubner, Guiber and Picker. Leipzig, Huzel. .12 pairhall, L.T. and Sayers, R.H. (1940). U.S. Pub. Health Bull., No. ^53* 13* Selby Smelter Commission Report. (I915). Bull. 98, Bureau of Mines. 14. Kent, I'T.L. (1942). J.Soc. Chem. Ind. bl:183. KE 0010 82 Eggs ? Si- ^foqq 41 h CD B CD O' ca H WMW -0 Vo \Q C3 t O' O O M B o o 3 c+ CD 3 c+ IQ 2 P t-> 4iCO 43 bC* s 3 W 4 W H -3 o M ta P O o oq o H- o H* I gCD H 3 p- 3* g3 CD 4 CD 4 < 1 S fed M O o oq oq O' H vO VO n O Vo oo <2 h1 O Vo VO H t-> p} 5^ H u> Ut vn O oOo g c+ 3 OQ CQ Ciq oq HO O H5 M 41 H* VO VO g3 oq O VO 4-" O' O' 43 Vft CO c* h-> 43 vO C? f H JO ifO 20 20 VO CD 4>VJl O' ( O o HH OO OO oq oq o gJO O' o o ro o s p- H vn O Ut O Ut O Oq oq o#q 5 SO' VJt 4 vO H H JO O' 03 o X vo o p- Ta p 4 P ct* 3 45 H* O * Hi g oq S 43 I--1 43 CD O' g Se ts tel HORSE ' SAMPLES 100 5. K BTg H* H* H> W s, 3g < co <? *! 3* H* gP C+" CD P* CD S.SL & ct- B^ oP CD H 0 CD H> g Pj C+ g g4 O' 1 3. H1 ICD c+ S 0 C+* 1 3 a c+ 0 O' CD Hi 1 g ta s Hi ? O B H U1 o O' o 8 vn O Oq oq cq oq 0 H jo 1vn O IO o sOl oH aV>) fe ~*3 Ul 03 -P~ <j Cq O' 03 -P~ vn H H UJ O O O O H Ut oq oq . Oq o o o e o JO o vn a 03 O' a sp o 4>03 O' MH OO OO oq oq I-* 4>* o JO H PO JO .I*C3 HO (D WK P Oq 3 H3 CD O' ^ ** OH O O a ts fej K W o w co fed H O O 03 vn CJq o q O *o voo H H VOO OH vo JO Wp> c+ 3. ' Ho l-D 0 cprfq P3 #hd d p* g; (jq *@ <s 5H o o 3 3 ts o f w o ss CO fed KF * sHE1 H?* Hj CJ a o' a 4P PP H* 3 -3 aP cF+* 5=3 P" F* OP P c+ CD P C<Ds 3 F* FPi Cjg^ OP CD P 0 CD H) P P 4 O' P CD 1P6 Hf4* JOSra s p CD P * O c+ o o' a CD CD P c+ O O' P Hj 4 o a ccir- p a p @ P s i? 2 p *d P a CO p 4p a 4o p c+ ap CD a a c+ p p o o -J p o u> VjJ p JO o j o j o VO 4>- 00 4>Vn O' co ap O o 100 p o o OX) cs oo JO IO' oo 1JO O' p on o Vn o vn o CK5 Cl? P5 O' 5 VT( p- P v> vO j o O' 00 o * u> CO S3 B c+ * Ir1 P p Hj co S P {K5 a# -o . . pp P o' 'l--~7? K eg qraj a p4 o o p Vn O' o \J1 P- pp oo W ooo ~p oo 3 o *d W era era ora era ora era po O H> S3 ts o o p o o p P~ K H JO o O' o JO c3 TO 03 H vO 03 *o p *3 K Q JOS', O id p a &VjJ p P -O Vn 00 -Pvn <o Cra (TO CO 3 ap o o P p Vn p o O o p o CO Oo o vn o era era vn era era ora p o S3 P Hs *P FJ ao i: o o JO VJt o o op VwO o co ora e :H y ^d o t-i CO o p Vo "p ^ p i?o Q M o o o o pe o o oH Va > o Cra id O 00 Cn O' H ! faA p CO o o tr-J ao o o o o O CN MO vO o O' 1 a o H- O P g1 i ( M s|c Vj J u> o o ! ! era dra' Ui so Ul so p O' TO CO I a *-v o ;* : i s si I I w as t?J ! iS: Table 3 VEGLTATIUK ANALYSIS. Point. 2 7 1 4 o o o "O' 5 Ui * Year. 1942. 1943. 1944 1945. 1946. 194b. I947. 1943. 1949. 1950. Oats. Oats. ii iTOClt * Hay. Wheat. Kay. Oats. Oats. Wheat. (Grass. 1942. 1943. 1944. 1349. 1946. 1947. 194d. I949. 1350. Oats. Oats. (Grass. 1942. 1943. 1944. I945. I946. I947. 1948. I949. 1950>. Oats. Oat s Oats. Hay. Oats ( Gras-. 1942. 1943. 1944. 1945. 1946. 1947. 1948. 1949. 1950. Hay. nay. Oat s (Grass. 1942. 1^43. 1944. 1943. 194.J. Wheat. Grain . Chaff. Stray/. Hay. Remarks. 2.7 6.9 2.2 4.3 - 2.0 48 12.2 -- 123 123 37 211 71 112. 8 -- 11 11 40 - 39 18 2b - 30.4 263.5} tr - 71 - 24 - ) ) ) ) ITo significant ) change except r increase ir; 1 wheat grain. 1 and grass. ) ) ) * * O.9 1.9 - 3.8 2.2 4.0 - - 22.4 - - 28.4 _ - 7.4 mm - -- 38 9.5 - -- 104 23 - -- -- - - -- 292.8 -) ll._ _ 0O7 111 208 - - 90 38 - 21 - -- -133*2 I06O 1350 - - 78 - - -} - - 512 -- _ - - 680 1348- 139 - - - - 235 - - r_ . - -- --- -- 270 73 - ) ) ) ) } High prass 1 figures in ) 1350. ) ) ) ) )1\ 'Harked and ) dangerous ) increase in ) 1950. )) ) ) ) ) ) ) ) High figures ) in 1350. r Oomnare with ) point 5* ) ) ) ) ) ) ) Hi.-.h figures 1 TO xyaa 1945. 1946. 1946. 1947. 1948. 1949. . 1950. <VUix C Hay. '.Vhsat. Hay. Oats. Oats. wnsat (Grass. 2.2 37 -- 4.3 211 -- 2.0 71 48 -- 12.2 112..8 40 - 3v 13 20 30.4 263.5) - 71 24 - ) ) Ho significant ) change except ) increase in )1 wheat grain. and grass. ) ) ) I I I 1 1 7 1942. 1949. --, ) - - -- ) 1944. Oats. 1949. 0.9 38 -- 9-5 -- ) ) I946. Oats. 1947. 1-9 104 23 - - -- ) High glass ) figures in 1 1 1949. - - --- ) 1950. 1949. - - - - .) 1950. (Grass. 292.8 A ) 1 1942. _) 1943. - - -- ) 1944. Oats. 5.8 0O7 90 - ) I945. Oats. 2.2 111 _38 - ) Harked and 1946. - - -- ) dangerous '| 1947. Oats. 4.0 208 21 ) increase in - - - 78 } 1930. 1948. - - - - )) 1949. - - -- ) 1950. Oats. 22.4 133.2 I06O - ) ( a: 3 ** 1350 -) ) 4 1942. ) 1943. Hay. - - - 139 ) 1944. - - -- ) 1943. - - -- ) nigh figures .. 194b. - - - - ) in 1550. 1947. - - - - ) Goaoars v/ith 1943. Hay. 1949. - - - 235 ) point 5* - -- ) 1950. Oats. 28.4 512 680 - ) (Grass. 1348- ) 5 1942. _ _) 1>43. - - -- ) 1944. -- --) 1943. - - -- ) High figures 1946. 7-4 270 5o - ) in I95O. I947. - - - -- ) Compare with. 1948. Oats* 39 31 -- } point 4. 1949. - - z- ) 1950. Hay. - - - 620 ) (Grrass - - 1921 -) ) Hoint 6 3 Year. 1942. I943. I944. I943. 194o. I947. 1948. I949. 1950. (Grass. Grain. Chaff. Straw. Hay. _ - - -- - -- - -- - -- - -- - -- - -- 1181) Remarks. 1942. 1943. Oats. Oats. Hay. 1944. I945. 1946. 1>47. 1943. 1949. 1930. W'cL'oS Bheat. 0ct 0 3 * Hay. .vheat. Hay. 0ci"fc 3 nay. Hay. Oats and Barley. (Grass. . 0.14 0.9 - 0.4 0.6 .1.1 0.9 0.6 -- 18.4 - 6.6 36.0 - 14.0 1.2 35.0 - 13.0 - 35 * - 36.8 -' 2.2 6.9 - 2.4 0.7 15.0 3.4 4.9 -- 48.4 22.0 31.0' -- 8.3 - 2.3 -- 7.6 - - 55-3) ) ) ) ) ) ) ) A "control" ) point. ) ) ) ) ) ) ) ) ) Control. Grass sample with sooty deposit from lawn in Rudheath, TTorthwich. 8*9 ppni. lead.' RE 00100&7