Document bBz76jNNb4YN1neZyxB02487O

INDUSTRIAL HYGIENE FOUNDATION OF AMERICA, INC. Mellon Institute, 4400 Fifth Avenue Pittsburgh 13, Pa. Report on A COMPARISON OF THE SUBACUTE INHALATION TOXICITY OF ETHYLENE DICHLORIDE, TRICHLOROETHYLENE, AND A MIXTURE OF THE TWO for PITTSBURGH PLATE GLASS COMPANY March-June 1961 by James M. McNerney, M. P.H, Research Toxicologist Paul Gross, M. D. Research Pathologist SL 082907 H. H. Schrenk, Ph.D. Managing Director  l. INTRODUCTION This report presents data and conclusions on the subacute in- halation toxicity of a mixture of trichloroethylene (67%) and ethylene dichloride (33%) containing a stabilizing system. The objective of the study was to determine if there is significant synergistic action, as revealed by behavioral, growth, mortality, and pathological data, on laboratory animals exposed to the vapors of the mixture. The effects were evaluated by comparing the response on a group of rats subjected to the vapors of the mixture during daily exposures with the effect on rats similarly exposed to trichloroethylene and ethylene dichloride vapors, alone. (1. Z) Adams, Spencer, et al reported that rats exposed to 400 ppm of ethylene dichloride for three, daily, seven-hour exposures had a mor tality of 60%, a rapid loss in body weight, a slight increase in liver and kidney weights, and upon histopathological examination revealed slight cloudy swelling of the liver with a few large fat vacuoles but no kidney damage. Rats exposed to 200 ppm of ethylene dichloride tolerated 151 exposures in ZIZ days and showed no evidence of adverse effects as judged by general appearance and behavior, growth, mortality, or histopathological exami nation. In exposures to trichloroethylene groups of rats tolerated 400 ppm for as many as 173 exposures in Z43 days without evidence of adverse effects as judged by mortality or general appearance and behavior. Growth curves were slightly depressed, liver and kidney 082908 SD 2. significant changes were observed in any tissue upon histopathologtcal ex amination. Rats exposed to 200 ppm of trichloroethylene toLerated as many as 151 exposures in 205 days without adverse effects as judged by general appearance and behavior, mortality, growth, organ weights, and histopathological examination of tissues. On the basis of these studies it was decided to employ the effects on rats exposed to ethylene dichloride, the more toxic of the two solvents, as the point of reference in this study. Since at the 400 ppm concentration level the trichloroethylene rats exhibited a greater increase in liver and kidney weights than the ethylene dichloride but upon histopathological exami nation showed no lesions while the ethylene dichloride did, organ weights were considered irrelevant to this study. The effects considered of prime significance in this study are growth, mortality, and pathological. A con centration and length of daily exposure of ethylene dichloride was chosen so as to produce a response severe enough to cause some mortality by three weeks and sufficient data to terminate the study after approximately one month. The length of daily exposures were to be increased if effects were not adequate. The same volume of liquid as was evaporated to yield the ethylene dichloride concentration was used for trichloroethylene and the mixtures of ethylene dichloride and trichloroethylene so that the exposures were comparable on the basis of liquid vaporized. Each group of rats was thus exposed to the same liquid volume of its respective solvent for equal periods of time. SI 82909 I I 3. MATERIALS AND METHODS A five gallon drum each of the Trichloroethylene-Ethylene Dichloride Mixture, Reference No. 61701-3-213-231, hereafter referred to as the mixture; of Trichloroethylene, Reference No. 61701-3-2 13-230, hereafter referred to as TCE; and of Ethylene Dichloride, Reference No. 61712-3-213-232, hereafter referred to as EDC was received for testing. The apparatus consisted of three, seven-cubic-foot, stainless steel chambers, three vapor generating units, and analytical chemical equipment. Each chamber contained five animal cages, had a glass-windowed door for observation of the animals during exposure, and was constructed to maintain the animals twenty-four hours per day. Each vapor-generating unit was composed of a monodrum mechanism, ^ a single syringe feeder,^ ^ a glass Graham condenser, and glass and tygon tubing connections. The monodrum mechanism drove the single syringe feeder, which contained the solvent, at a calculated, constant rate, delivering the required amount of chemical into the condenser. Hot water was passed through the outer jacket of the condenser and as the solvent was dropped into its spiral, tubular cen ter, it was evaporated, mixed with air, and drawn through the chamber. The calculated vapor concentrations were in good agreement with the results of analysis by combustion and determination of total halogen colorimetrically (5) using mercuric chloranilate. SL 082910 4. Twenty-five male, albino rats were exposed to each compound. They were fed ad libitum on Purina Lab Chow except during the exposure when water and feed were withheld. The rats were weighed each morning before the exposure. Animals that died during the testing period and those sacrificed terminally were subjected to autopsy and the lungs, livers, and kidneys were dissected for histopathological preparation and examination. The experimental conditions are presented in Table 1, As sub noted in the table, the length of exposure was increased during the study from five hours per day to eventually seven hours per day in order to pro duce more significant effects within the proposed one-month period. The EDC concentration, upon which the concentrations of the other solvents were based, was held constant during the study at 300 ppm, midway between the 200 ppm no effect level and the 400 ppm, 60% mortality level. Table 1 -- Exposure Conditions Solvent Concentration ml. /I. mg. /I. ppm EDC TCE Mixture 0.000951 1. 194 0.0009502 1. 392 0.000952 (EDC 0. 395 (TCE 0. 934 301 260 100 174 See text for explanation of variation. Daily (hrs) Length of Exposure Actual Exposure Overall Period (days) (days) 0_ - _1 24 5-7 24 5-7 24 32 32 32 SL 082911 3. RESULTS The mortality data are presented in Table 2, Table 2 -- Exposure Results Solvent Weight Data Original Average Final Average (gms.) (gms.) EDC TCE Mixture 200 200 200 278 312 307 Mortality Data Extraneous Experimental No. % No. /o 14 00 14 12 48 28 00 The striking lethal effect of the EDC (48%) is shown in contrast to the lower mortality of TCE (8%) and the absence of experimental death for the mixture. The extraneous deaths occurred during the second week of ex posure and were of probable bacterial origin showing signs of severe pneu monia and slight empyema. The experimental TCE deaths occurred during the third and final weeks of the test period. Five of the experimental EDC deaths occurred during the third week and seven during the final week. Table 2 also shows that the increase in weight of the TCE and mixture ex posed rats significantly exceeds that of the EDC exposed rats. The difference in growth effect is graphically presented in Figure 1. The following points should be noted: The three curves were distinct following the third day of exposure but even after three weeks their difference was not of a high level SL 082912 I 6. of significance. After increasing the exposure periods to seven hours there was a definite effect on growth. Concern over the possible killing of all of the EDC exposed rats brought about trials with different lengths of exposure periods during the third week. However, it was finally decided to continue the exposure length at seven hours during the remainder of the study. The sharp dips in the EDC growth curve (mean weight) are due to acute weight losses in a number of severely affected rats. The subsequent sharp rises in the curve are due to the removal of the animals from subsequent calculation of the mean weight after their deaths. The kidneys and livers of five of the EDC fatalities were examined microscopically. All showed severe renal tubular necrosis, enough to account for the death of the animals. One animal showed, in addition, hepatic necrosis. Ten of the surviving animals were also similarly examined. All three groups were represented and no significant or constant renal or hepatic lesions were found. The lungs of the surviving animals, however, showed minor de grees of focal chronic interstitial pneumonitis, characterized by cellular proliferation and desquamation. SL 082913 3 7. CONCLUSIONS Rats exposed for the same period of time and to the same vapor ized volume of a TCE (67%)-EDC(33%) mixture as those exposed to EDC and TCE alone, exhibited a lower _mortality rate than either and a growth rate intermediate between the two. Volume for volume, the mixture was less toxic than EDC alone, and was similar in toxicity to TCE, the major constituent of the mixture. Hence, the toxicity of the mixture was essentially that which would be expected from a simple summation of the toxicities of the constituents. (6 7) These results are in general agreement with other studies' ' ; of toxicities of mixtures of halogenated and other organic solvents. SL 082914 8. REFERENCES 1. Adams, E. M. , et al; Vapor Toxicity of Trichloroethylene Determined by Experiments on Laboratory Animals, A.M. A. Arch. Ind. Hyg. & Occ. Med. 4, 469, 1951. 2. Spencer, H. C., et al: Vapor Toxicity of Ethylene Dichloride Determined by Experiments on Laboratory Animals. A.M. A. Arch. Ind. Hyg, & Occ. Med. 4, 482, 1951. 3. Monodrum Apparatus manufactured by Gorrell & Gorrell, Westwood, N. J. 4. Single-Syringe-Feeder manufactured by Modern Metalcraft, Midland, Mich, 5. Method for. the Determination of Chloride Using Mercuric Chloranilate. Fisher Scientific Company Technical Data Sheet. 6. McCollister, D. D. , et al: Comparative Inhalation Toxicity of Fumigant Mixtures. A.M. A. Arch. Ind. Health^, 1, 1956. 7. Pozzani, U.C. , et al: The Toxicological Basis of Threshold Limit Values: 5. The Experimental Inhalation of Vapor Mixtures by Rats, with Notes Upon Relationship Between Single Dose Inhalation and Single Dose Oral Data. Am. Ind. Hyg. Assoc. J. 20, 364, 1959. SL 082915 R at W eight in G ram s SL 082916 3to 3/0 300 2<f0 Ho 2yo 2i,o Z30 tSC rzo Ztc Zoo A / F igure 1 __ Growth Effects Solvents * TCE Mixture + EDC io /r 20 Overall Experimental Period in Days Exposure Lengths A-B B-C C-D D-E E- 5 hours 7 hours 6 hours 6. 5 hours 7 hours 2T Jo TABLE g4 _ Urinary leukocytes in control and ECD-exposed male rats. Group 1 Rat N Group 2 Rat N Group 3 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X Oc jtlrj 1 1 1 1 1 2 2 '2 1.5S 1245 1246 1247 1248 1250 1251 1252 1253 0 = absent 1 = traces 2 = discrete quantitaties 7 1275 1 1277 1 1278 2 1279 \ 2 1280 i 1281 i 12S2 i 1285 1.38 1 1 2 2 2 1 1 1 1.38 Group 4 Rat X Group 5 Rat N 1303 1504 1305 1506 1307 1308 1309 1310 \ 2 1333 1 1334 1 1355 2 1336 2 1338 2 1340 2 1341 j 1342 3 1.88 i! 2' i 3 2 2 7 l 1 1.75 o 03 IJ\j TABLE 85 - Urinary crystals in control and ECD-exposed female rats. Group 1 Rat N 1201 1203 1204 1205 1208 1209 1210 1212 X 1 1 0 0 2 1 2 i 1.00 Group 2 Rat N 1231 1233 1234 1235 1237 1238 1240 1242 2 1 2 2 2 2 2 1 1.75 Group 3 Rat N 1262 1263 1264 1265 1266 1267 1270 1271 2 2 2 2 1 2 2 1 1.75 Group 4 Rat N Group 5 Rat N 1291 1292 1293 1294 1295 1297 1298 1299 1 2 1 0 0 2 1 2 . \ 1.13 1321 1323 1325 1326 1327 1328 1330 1332 3 2 2 1 3 2 i 2.00 0 = absent 1 = traces 2 = discrete quantitaties 3 = high quantity cn F o oo to vo to o TABLE 86 - Urinary crystals in control and ECD-exposed male rats. Group 1 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X 2 0 0 2 1 1 1 1 1.00 Group 2 Rat N Group 3 Rat N 1245 1246 1247 1248 1250 1251 1252 1253 1 1273 2 1277 2 1273 1 1279' N 1 1280 1 1281 1 1282 1 1285 1.25 4, 2 2 1 2 2 2 1 1.75 Group 4 Rat N Group 5 Rat N 1303 1304 1305 1306 1307 1308 1309 1310 \ 1 1 4 2 2 1 ? 2 1.38 13 a? 3 1354 1335 1336 1338 1340 1341 1342 3 2' 2 1 1 3 3 2 2.13 0 = absent 1 = traces 2 = discrete quantitaties 3 = high quantity 4 = very high quantity SL 082921 --0 TABLE 87 - Urinary erythrocytes in control and ECD-exposed female rats. Group 1 Rat K \ 1201 1203 1204 1205 1208 1209 1210 1212 X S.E. 0 0 0 0 0 0 0 0 0 0 = absent Group 2 Rat N 1231 1233 1234 1235 1237 1238 1240 1242 0 0 0 0 0 0 0 0 0 Group 5 Rat N 1262 1263 1264 1265 1266 1267 1270 1271 0 0 0 0 0 0 0 0 0 Group 4 Rat N 1291 1292 1293 1294 1295 1297 1298 1299 0 0 0 0 0 0 0 0 \0 Group 5 Rat N 1321 1323 1325 1326 1327 1328 1330 1332 | j i 0] 0 0 0 0 0 0 0 0 co tr1 o oo M CO fo KJ -Ty At TABLE 8S - Urinary erythrocytes in control and ECD-exposed male rats. Group 1 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X 0 0 0 0 0 0 0 0 0 Group 2 Rat N Group 3 Rat N 1245 1246 1247 1248 1250 1251 1252 1253 0 1273 0 1277 0 1278 0 1279 \ 0 1280 0 1281 0 1282 0 1285 0 0 0 0 0 0 0 0 0 0 0 = absent 1 = traces 2 = discrete quantitaties Group 4 Rat N 1303 1304 1305 1306 1307 1308 1309 1310 \ 0 0 2 0 0 0 0 0 0 Group 5 Rat N 1533 1334 1335 1336 1338 1540 1341 1342 0 O' 0 0 0 0 0. 0 0 I TABLE 89 - Urinary mucus in control and ECD-exposed female rats. Group 1 Rat N' 1201 1203 1204 1205 1208 1209 1210 1212 X 1 1 1 2 1 1 1 2 1.50 Group 2 Rat N3 1231 1233 1234 1235 1237 1238 1240 1242 1 1 2 2 1 1 2 1 1.58 Group 3 Rat N 1262 1263 1264 1265 1266 1267 1270 1271 1 2 1 2 1 .1 1 1 1.25 Group 4 Rat N Group 5 Pat N j i 1291 1292 1293 1294 1295 1297 1298 1299 1 1 1 1 0 2 2 1 1.00 1321 1323 1325 1326 1327 132S 1330 1332 5 i i 3 3 ~ n 3 2.25 0 = absent 1 = traces 2 = discrete quantitaties cn F 3 = high quantity o co to kO fO TABLE 90 _ urinary mucus in control and ECD-exposed male rats . Group 1 Rat N Group 2 Rat N Group 3 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X 2 9 U 1 1 1 2 1 '1 1.38 1245 1246 1247 1248 1250 1251 1252 1253 0 = absent 1 = traces 2 = discrete quantitaties 3 = high quantity 1 1273 1 1277 2 1278 2 1279 \ 1 1280 1 1281 1 1232 1 1285 1.25 1 1 1 3 2 1 1 1 1.25 Group 4 Rat N Group 5 Rat N -- ---------------------------------------------------- -i 1303 1304 1305 1306 1307 1308 1309 1310 "\ 1 1533 2 1334 1 1335 1 1336 1 ! 1358 1 1540 1 1341 2 1342 1.25 2 2 1 1 9 l i] 3 1.63 SL 082925 TABLE 51- Urinary epithelial cells in control and ECD-exposed female rats. Group 1 Rat N Group 2 Rat N 1201 1203 1204 1205 1208 1209 1210 1212 X 1 1 1 1 2 1. 2 2 1.38 1231 1233 1234 1235 1237 1233 1240 1242 0 = absent 1 = traces 2 = discrete quantitaties 3 = high quantity 1 1 1 2 1 1 2 1 1.25 Group 3 Rat N 1262 1263 1264 1265 1266 1267 1270 1271 2 2 2 1 1 1 1 1 1.38 Group 4 Rat N Group 5 Rat N 1291 1292 1293 1294 1295 1297 1298 1299 1 1 2 1 1 1 1 2 \ 1.25 1321 1323 1325 1326 1327 1323 1330 1332 1 2 2 3 1 1 2 1 1.65 co o CD to U3 to CO TABLE 92 - Urinary epithelial cells in control and ECD-exposed male rats. Group 1 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X 1 1 1 2 2 1 1 1 1.25 Group 2 Rat N Group 3 Rat N 1245 1246 1247 1248 1250 1251 1252 1253 1 1273 1 1277 2 127S 2 1279 \ 1 12S0 1 1281 2 1282 2 1285 1.50 1 1 1 1 1 1 1 1 1.00 Group 4 Rat N Group 5 | Rat '1 | 1303 1304 1505 1306 1307 1308 1309 1310 \ 0 1 2 1 1 2 2 1 1.25 1333 1334 1335 1336 1538 1340 1341 1342 1 2 0 1 1 2 J 1 1.50 0 = absent 1 = traces 2 = discrete quantitaties cn f TABLE 93 - Urinary microorganisms in control and ECD-exposed female rats. Group 1 Rat N 1201 1203 1204 1205 1208 1209 1210 1212 X 1 1 1 2 1 1 1 1 1.15 Group 2 Rat N 1231 1233 1234 1235 1237 1238 1240 1242 1 2 2 1 1 2 1 1 1.38 Group 3 Rat N 1262 1263 1264 1265 1266 1267 1270 1271 1 2 -1 1 1 1 1 1 1.13 Group 4 Rat N Group 5 Rat N 1291 1292 1293 1294 1295 1297 1298 1299 1 1321 1 1323 1 1325 1 1326 1 1327 2 1328 1 1330 2 1352 \ !-25 1 2 3 4 2 2 2 2 2.5S 0 = absent 1 = traces 2 = discrete quantitaties to t* 3 = high quantity o oo 4 = very high quantity to U) to oo TABLE 94 - Urinary microorganisms in control and ECD-exposed male rats. Group 1 Rat N Group 2 Rat N Group 3 Rat N 1215 1217 1218 1219 1220 1221 1222 1224 X 2 2 1 1 1 1 1 1 1.25 1245 1246 1247 1248 1250 1251 1252 1253 0 = absent 1 = traces 2 = discrete quantitaties 3 = high quantity 4 = very high quantity 1 1273 2 1277 ? 1278 1 1279 S 2 1280 i 1281 2 1282 1 1285 1.50 2 2 2 1 1 1 1 1 1.38 Group 4 Rat N Group 5 Rat N 1303 1304 1305 1306 1307 1308 1309 1310 2 i 4 1 1 l 1 2 1.63 1333 1334 1335 1336 1338 1340 1341 1342 2 4' 2 2 4 ? 4 5 2.88 SL 082929 TABLE 1 Experiment BT501 : Exposure by inhalation to Dichloroethono in air at 250-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. , Besult3 after 104 weeks. DISTRIBUTION OF THE DIFFERENT TYPES OF TUUGURS H-- 1 ANIMALS (Sprague-Dawley rats, 12 weeks old at start) '1* Sex No .at No.sur 3 tart vivors Corrected number (b) 250-150 O' SO 1 ppm 0 90 1 (a) 0* and 180 2 O' 50 ppm $ <7* and 0 0' 90 T 8 90 7 180 15 90 2 9 90 0* and (J 1 180 0* 90 7 9 13 9 0" and ^ 90 180 13 26 89 90 179 90 90 180 89 SO 179 90 90 180 Mammary tumours (c) Average To latency tal No. (d) time (weeks) (e) 10 11.2 91.2 52 57.7 78.6 62 34.6 80.6 8 8.9 67.5 55 61*1 76.7 63 35.0 75.6 5 5.6 60.8 43 47.s 79.9 48 26.3 77.9 6 6.7 93.7 64 71.1 82.6 70 38.9 83.6 Zyrabal gland carcinomas Average To latency tal No. * time (a) (weeks) (f> 0- - 2 2.2 78.0 2 i.i 78.0 0- - 1 1.1 86.0 1 0.5 86.0 0- - 0- - 0- - 0- - 2 2.2 47.0 2 1.1 47.0 ANIMALS WITH TUMOURS Bemat ofibromas Leukaemias Average Averagfe To latency To Tatency tal No. je (a) time (weeks) tal No. * time (a) (weeks) 1 (f) . <f) 4 4.5 57.0 0 - - 0- - 0- - 4 2.2 57.0 0 - - 6 6.7 66.0 1 1.1 80.0 0- - 1 1.1 48.0 6 3.3 66.0 2 1.1 64.0 1 1.1 58.0 2 2.2 34.0 0- - 0- - 1 0.5 58.0 2 1.1 34.0 5 5.6 52.8 0 - - 0- - 5 5.6 75.2 5 2.8 52.8 5 2.8 75.2 .t Other tumours Total (g) To tal No. 3 Benign No. 2 Kalijr nant No. No. 1 15 1* (a) 16,8 No. of diffe rent tu mours/ tumours bearing animals 1.7 8 3 5 52 57 .7 1.2 11 5 6 67 37.4 1.2 7 6 1 17 18.9 1.3 5 3 2 59 65.5 1.0 12 9 3 76 .42.2 1.1 4 1 3 11 12.3 1.1 3 2 1 43 47 .8 1.1 7 3 4 54 30.2 1.1 9 6` 5 - -.2 14 8 3 16 20.0 .1.1 - 3 6.9 76.7 - 1.1 - V 6 87 48.3 i.r rols j.n 3 O' 04 C* and 9 Icontrols 0" 9 O' and 0 SO . 3 so 3 ISO 6 90 2 90 12 180 14 90 50 180 90 90 180 7 7.8 87.4 1 1.1 70.0 36 40.0 81.2 0 - - 43 23.9 82.2 1 0.5 78.0 4 4.4 84.5 1 1.1 74.0 47 52.2 82.7 0 - - 51 28.3 82.8 1 0.5 74.0 2 2.2 53-0 1 1.1 37.0 6 0- - 3 3.3 66.3 4 2 1.1 53.0 4 2.2 59.5 10 0- - 0- - 6 00- - 3 3.3 79.3 5 - 3 1.7 79.3 11 4 . 2 14 15.5 1.2 2 2 38 42.2 1.1 6 4 52 23.9 i.i 6 0 11 12.2 1.0 2 3 49 54.4 i.i 8 3 60 33.3 1.1 V and _VI Total N Controla '- O' 0* G* and 0 180 180 360 I.OSO 5 15 20 72 150 180 360 1.078 11 6.1 86.3 2 1.1 76,0 S3 46.1 82.0 0 - - 94 26.1 82.5 2 0.5 76.0 1 2 1.1 53.0. 1 0.5 37.0 12 0- - 6 3.3 72.0 9 2 0.5 53.0 7 1.9 67.7 21 1 10 4 14 2 | 25 13.9 5 67 43.3 7 112 31.1 1 1.1 1.1 1.1 SL 082930 SL 082931 -- TABLE 1 Experiment BT501 : Exposure by inhalation to Dichioroethane in air at 250-150, 50, 10, 5 ppm, 1 * TABLE ^Experiment BT501 : Exposure by inhalation to Dichloroethane in air at 250-150, 50, 10, 5 ppm 7 hours daily, 5 days weekly, for 78 weeks. Y Results after 104 weeks. DISTRIBUTION OP THE DIFFERENT TYPES OF MAMMARY TUMOURS (second part) (a) After few weeks the dose was reduced to 150 ppm, because of the too high toxicity at 2 50 ppm level. (b) Alive animals after 12 weeks, when the first tumour (a mammary carcinoma) was observed. (c) Two or more tumours of the same and/or different types (fibroadenomas, carcinomas, sar comas, carcinosarcomas) may be present in the same animal. (d) The percentages are referred to the corrected number. (e) Average age at the onset of the first mammary tumour per animal, detected at the perio dic control or at autopsy. (f) The percentages are referred to total numberof animals bearing mammary tumours. (g) The percentages are referred to total numberof animals bearing mammary tumours, histo logically examined. i TABLE 3 Y'fecprlROnt BTJOl : Exposure- by inhalation to Dichloroethane in air at 230-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. JHV'; DISTRIBUTION OF THE DIFFERENT TYPES of MISCELLANEOUS ("OTHER") TUMOURS Benign ANIMALS BEARING OTHER TUMOURS Maiignan t Distribution of histotypos No Distribution of histotypos Total 1 Zymbal gland adenoma 1 pheochromocytoma 1 peritoneal fibrosarcoma 1 Zymbal gland adenoma 1 lutcoma 1 adenoma of the uterus 1 adenocarcinomaiof stomach 1 adrenal gland cortical adenocarcinoma 1 granulosa cells carcinoma of ovary 1 adenocarcinoma of the uterus 1 squamous carcinoma of the uterus 2 skin cystic acanthomas 1 forestomach papilloma 1 adrenal gland cortical adenoma 1 pheochromocytoma 1 Leydig cells tumour 1 skin basocellular carcinoma 1 skin cystic acanthoma 1 Zymbal gland adenoma 1 polypus of the colon 1 fibrosarcoma of the uterus 1 peritoneal mesothelioma l 1 adrenal gland cortical adenoma 1 forestomach papilloma 1 pheochromocytoma 1 skin squamous carcinoma 1 adrenal gland cortical adenocarcinoma 1 pleural mesothelioma 1 adenocarcinoma of the uterus 1 forestomach acanthoma 1 cholangioma , 1 adrenal gland cortical adenoma 2 Leydig cells tumours 1 ganglioneuroma 1 Zymbal gland adenoma 1 liver histiocytosis 1 skin cystic acanthoma 1 subcutaneous lipoma 1 forestomach acan thoma 1 pheochromocytoma 1 skin cystic acanthoma 1 forestomach acanthoma 1 subcutaneous fibrosarcoma 1 nephroblastoma 1 neurilemoma 1 intestinal fibrosarcoma 1 granulosa cells carcinoma of ovary 1 adenocarcinoma of the uterus 1 skin fibrosarcoma 1 meningioma 1 subcutaneous rhabdomyosarcoma 1 squamous carcinoma of the uterus 1 skin acanthoma 1 skin cystic acanthoma 2 Zymbal gland adenomas 1 subcutaneous lipoma VI 1 benign neurilemoma 2 adrenal gland cortical adenomas 1 liver fibrosarcoma 1 adenocarcinomi of the uterus 1 neurilemoma 1 skin, acanthoma 2 skin cystic acanthomas 2 Zymbal gland adenomas' 10 2 subcutaneous lipomas 1 forestomach acanthoma 1 pheachromocytoma ' V 1 benign neurilemoma and VI 1 skin cystic acanthoma 1 forestomach acanthoma .9 2 adrenal gland cortical adenomas 1 skin fibrosarepma 1 meningioma 12 1 subcutaneous rhabdomyosarcoma 1 liver fibrosarcoma 1 adenocarcinoma of the uterus 1 squamous carcinoma of the uterus 1 neurilemoma SL 082934 m. ... h\ i * ' ' Ws^Vp' ' f'Wjl'*i' `\*]>. : - TABLE 4 leriraent BT501 Exposure by inhalation to Dichloroethane in air at 250-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. m, INCIDENCE OF PITUITARY ADENOMATOUS GROWTH Ilf- ' mmtr .mm1' CONCEN TRATION 250-150 ppm (a) ANIMALS (Sprague-Dawley rats, 12 weeks old at start) Corrected Sex No .at No,sur start vivors number (h) 90 1 89 9 90 1 90 0* and Q 180 2 179 wp:' 50 ppm o3 9 0* and Q 90 90 180 8 7 15 90 90 180 0" 90 2 89 10 ppm 9 90 7 90 -- Cf and 9 180 9 179 I): o* 90 13 90 5 ppm 9 90 13 90 r" 0" and 9 180 26 180 i. Controls cr 90 3 v in 9 chambers 90 3 QT and 9 180 6 90 90 180 j 0* 90 2 90 VI Controls 9 90 12 0* and 9 180 14 90 180 PITUITARY ADENO MATOUS GROWTH No. /o 1 1.1 0_ 1 0.5 07 7.8 7 3.9 03 3.3 3 1.7 3 3.3 8 8.9 11 6.1 2 2.2 5 5.5 7 3.9 1 1.1 7 7.8 8 4.4 V & 180 5 and Controls 9 180 VI 0* and 9 360 15 20 180 180 360 3 1.7 12 6.7 15 4.2 Total 1.080 72 1.078 (a) After few weeks the dose was reduced to 150 ppm, because of the too high`toxicity at 250 ppm level. Cb) Alive animals after 12 weeks, when the first tumour (a mammary carci noma) was observed. 82935 iIffSf:: TABLE 5 jBent BT501 : Exposure by inhalation to Dichloroethane in air at 250-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. Kryi-M';' ` INCIDENCE OF TERMINAL BRONCHIOLI HYPERPLASIA HBpl ;jlw0| J TO BgHpEk?.. W1MjsP9HWwtyF't ' ij| 1 KI SHfo'1 ` m KSs 'BHnttta' . 1 JaSSWri'; ^ , >'|j P" r fl^ if" ,CONCENTRATION 250-150 ppm (a) 50 ppm 10 ppm ' ANIMALS (Sprague-Dawley rats, 12 weeks old at start) Sex 0* 9 0"and Q No. at start No.sur vivors Corrected number (b) 90 1 89 90 1 90 180 2 1 79 cf 9 0* and O'* 9 cTand g 90 90 180 90 90 180 8 7 15 2 7 9 90 90 180 89 90 179 TERMINAL BRONCHIOLI HYPERPLASIA (TBH) No. % (c) 02 2.2 2 1 .1 2 2.2 5 5.5 7 3.9 010 11.1 10 5.6 i ,IV i \V cr 5 ppm 9 (f and 9 Controls in chambers 0* 9 Cf'and 9 90 90 180 90 90 180 13 13 26 3 3 6 90 90 180 90 90 180 4 4.4 2 2.2 6 3.3 3 3.3 3 3.3 6 3.3 0* 90 2 90 4 4.4 VI Controls 9 90 12 90 6 6.7 0* and 9 180 14 180 10 5.5 O'1 180 5 V and Controls 9 180 15 180 180 7 3.9 9 5.0 VI O^and 9 360 20 360 16 4.4 Total 1.080 72 1 .078 (a) After few weeks the dose was reduced to 150 ppm, because of the too high toxicity at 250 ppm level. (b) Alive animals after 12 weeks, when the first tumour (a mammary carcinoma) was observed. - v'j A- a-.,: ~: V* ' -frij fr -' ^oVognse vi Stu*c TABLE 6 Experiment BT502 : Exposure by inhalation to Dichloroethane in air at 250-150, 5C, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. *gg GROUPS COIIC SUI no. TSATION ANINALS (Swiss mice, 11 weeks old at start) Corrected Sex I!o. at Ko.sur start vivors number (b) 0* 90 i 250-150 mm 9 90 'N> 0* and 9 160 O1 90 ii 50 ppm 9 90 0* arid Y ISO 0* 90 hi 10 ppm 9 so O'1 and 0 130 O' 90 17 5 ppm 9 90 O' and C 180 O' . 90 V Controls 9 so O' ar.d 9 180 2 0 2 0 7 7 5 1 6 1 7 8 .2 5 7 83 85 ' 168 86 88 174 89 89 178 71 8 160 88 90 173 DISTRIBUTION OF THE DIFFERENT TYPES OF TUT'0033 Mammary tumours Average To tal < latency tine No. (c) (weeks) (0) ANIMALS V/ITK TUMOURS Pulmonary adenomas Leukaemias To tal No. Average latency To * time tal (o) (v:eeks) w No. Average latency * time (c) (weeks) (d) 0- - 0- - 1 1.2 77.0 5 5.9 68.8 2 2.3 84.5 1 1 .2 65.0 5 3.0 68.8 2 1 .2 84.5 2 1 .2 71.0 0- - 2 2.3 73.0 4 4.6 64.7 3 3.4 70.3 2 2.3 75.5 3 3.4 60.0 3 1.7 70.3 4 2.3 74.2 7 4.0 62.7 1 1.1 33.0 3 3.4 76.3 3 3.4 58.3 4 4.5 69.5 2 2.2 53.5 5 5-6 65,8 5 2.8 62.2 5 2.8 68.4 8 4.5 63.0 0- - 1 1 .4 44.0 1 1.4 80.0 4 4.5 80.0 -4 4.5 73.5 5 5.6 69.0 4 2.5 80.0 5 3.1 67.5 6 3.7 70.6 0- - 3 3.4 66.7 2 2.3 35.5 4 4 .4 70.7 3 3.3 53.3 6 6.7 50.2 4 2.2 .70.7 6 3.4 60.0 8 4.5 46.7 Other tumours To Malig tal No, Eenign No. nant If0 10 11 21 1 0 i 10 31 41 ' 0 21 31 i 2 3 1 1 2 00 0 1 0 .' 1 10 1 33 20 53 0 2 2 Total 800 30 858 \ A t 9 v ,->--i , , > Total (e) i's* of diiierer.i No. tur. r.irV (c) tir;c>ur bearing animals 2 2.4 1.0 9 10.5 11 6.5 1* 1.1 7 5.1 io 11.4 | 17 ?.sj 3 9*0 12 1 5 o j 20 11 .2 j 1.0 1.0 1.0 1 .^ 1' 1 .0 2 2.6 1 .0 14 12.5j 1 .0 16 l v: * b j 1 *<j n* 7*9 1.1 14 15o 1.1 21 11.6 1.1 SL 082937 -<o\o5nse> //S?%*. Sturf'**>> '-= A?S >. I 5SUS5-*1 1: TA3L3 6 (follows) Experiment 3T502 : Exposure by inhalation to Dichloroethane in air at 250-150, 50, 10, 5 cam, 7 hours daily, 5 days weekly, for 73 weeks. Results after 104 weeks. DISTRIBUTION 0? THE DIFFERENT TUBES 0? TUMOURS --2; animals tt start) Karmary tumours CROUPS COHCEH- Average 110. TRATIOK Sex Ho.at start Ho.sur vivors Corrected number 00 To tal Ho. s (c) latency tine (weeks) (d) O' 25 0 25 0- - VI Controls 9 44 4 44 1 2.3 65.0 O' and <J 59 4 69 1 1.4 65.0 ---- O' 115 2 113 0 - V and Controls 9 134 VI 0> and 0+ 249 9 11 134 247 5 3.7 69.6 5 2.0 69.6, AHInALS ViTTH TUMOURS Pulmonary adenomas Leukaemias Other tumours To tal Ho. * (c) Average latency time (weeks) (i) To tal Ho. Average JS (c) latency time (weeks) To tal No, Ber.ig:i No, Malig nant Ho. <d) 0- - 0 -- - i i0 1 2.3 45.0 5 11 .4 74. C 0 0 0 1 1.4 45-0 5 7.2 . 74.0 i 1 0 3 2.6 66.7 2 1.8 36.5 4 4 0 4 3.0 51.2 11 8.2 61,0 2 0 2 7 2.8 57.'8 13 5.3 57.2 6 4 2 Total (e) No, of diff^r^n- Sc. (c) tur.vjr?/ t'lr w-'*s r s beartr:r ani r..3.Z s i 4.0 1.0 7 * 15.9 S 11.5 1.0 --------------------- 1 liO j 8 7.1 21 15.7 29 11.7 1.1 1 .0 -1.1 Experiment BT502 : Exposure by inhalation to Lichloroethane in air at 250--150, 50, 10,^5 ppga 7 hours daily, 5 days weekly, for 78 weeks. . .* Results after 104 weeks. DISTRIBUTION OF THE DIFFERENT TYPES OF TUMOURS (a) After few weeks the dose was reduced to 150 ppm, because of the too high toxicity at 250 ppm level. (b) Alive animals after 23 weeks, when the first tumour (a leukaemia) was observed. (c) The percentages are referred to the corrected number. (d) Average time from the start of the experiment to the detection at the periodic control or at autopsy. (e) Several animals with two or more tumours. SL 082939 Sf "-' -* ' 'V" - [5 &3; v^:--*.-v*-V-,'^^5:?.4 ^rV": TABLE 7 'a- '-vwgh<V.-AiLy,_^<!?V. ^. ;.:>3 Experiment BT502 : Exposure by Inhalation to Dichloroothere in air et 250-150 , 50,' 10, ) >!*" 7 hours daily, 5 days weekly, for 78 weeks. A. Results after 104 weeks. .-. 1 ( piAAl. ,si., DISTRIBUTION OF THE DIFFERENT TYPES OP MV.''MARY TITOUHS 1 '?r; (first pi.-tj GROUPS CONCENno. TRATION ANIMALS {Swisa mice"] 11 weeks old at jstart; Sex Corrected No.at No.sur number To tal No. JS (c) Average No. of latency tumour z/ tine tumours (weeks) bearing tal No. * (e) start vivors (b) (8) animals MAMMARY TUMOli RS His tclogically examined His totype * Fibromas and fi br oad e nom a <* Average < latency No. time (f> (weeks) U) Carein0mas 4, No. (?) Average latency tine (vve c k s) w Sarcoma: s 4, No. (f) Average latency time (weeks) (6) Care in cat means a j T10, (I) latency car*.) (e) Cf 90 2 83 0- - - C- 0 - - 0- - 0 - `- 0- i pDn 9 90 0 6p 5 5.9 68.8 1 .0 5 100.0 0 - - 5 100.0 63.3 0 - - c- -i (a) o'ona Q ISO 2 163 5 3.0 68.3 1 .0 5 100.0 0 - - 5 100.0 68.8 0 - - 0- -1 cf SO 0 ii 50 ppm ? so 7 o' arid <1 iso 7 So 83 174 0- - - 0- 0 - 3 3.4 70.3 1 .0 2 66.6 0 - 3 1.7 70.3 1.0 2 65.6 0 - - 0_ - 0- - 2 1C0.0 57-0 0 - - 2 100.0 57.0 0 - - 0" - c- | i - 0- - O' ' SO 5 in 10 pom 9 so 1 0' and 0* 160 6 c1 - 90 1 . IV 5 ppm 9 90 7 O'and 9 180 6 89 89 1 ?3 71 69 160 1 1.1 33.0 4 4.5 69.5 5 2.3 52 ,, 2 0- - 4 4.5 80.0 '.1f 2.5 80.0 1 .0 1 100.0 1 100.0 33.o c - "- 1 .0 - 4 100.0 0 - - 4 1C0.0 69.5 1 .0 5 100.0 - 20.0 33.0 80.0 - 0- 0 1 .0 4 100.0 0 1 .0 4 100.0 0 - - 0- - - 4 100.0 80.0 4 100.0 80.0 00 0- 000- - 0- - - 0- _ - 0- - ------------1 - 0 - 1 ________| -0 j -c 1 O' so 2 y Controls 9 so 5 O1 ar.d 0 180 7 63 178 0- - - 0- 0 4.4 70.7 1 .0 4 j100.0 0 1 H 2.2 70.7 1 .0 4 j 1C0.0 0 | - - 0 - - 0- - 3 j 75.0 74.0 0 - - 3 75-0 | 74.0 0 - - 0 " i1 - !\ - 1 j 25-C 1 e .0 ] - 1 j 25.0 J '- ^ 1 1 Total | 900 30 853 1 _J__________1 SL 082940 ' k -..vt'-' `XVs CO t* o CO to vo >> ^osnesf. ,, /^?. \ ^'tu`*' ,,P'" \ tfftj*** TABLE 7 (follows) Experiment ST502 : Exposure by inhalation to Sichioroethane in air at 250-150, 50, 10, 5 per, 7 hours daily, 5 days weekly, for 73 weeks. Eesuits after 104 weeks. DISTEIBOTIOy 0? THE DIPPSHEHT TYPES OP r.'AM'APY TX'C''!S -------- AHIMALS (Swiss nioe^ 71 weeks old at start) GH0UPS CCHBXt- K0 . tratioh Sex Ho. at .-*n<1-vi *V Ko. sur vivors Corrected nurfoe r w vi V and VI <? 25 0 Controls ? 44 O'and 0+ 6 O' | 115 j 4 4 2 Controls 9 134 j 9 0* and {J 249 | 11 25 44 69 113 134 247 To tal Ho ) 0 1 1 Averagej Ho.of JS latency tumours/ To (c) time tumouro tal (weeks) hearing Ho. (d) animals - - |- P *> 65.0 j 1.0 1 .4 65.0 1 .0 0 1 1 Cc) 100.0 100.0 KA-MhUY TLY.JCUB.S Histologically examined ] Pi oror.as and fibroadenoma j j Kistotype Carcar.or.ns ! j ,, Sarcomas ` r- ! j Ho. (f) 0- Avn rc.;e latency tine (weeks) (ct) Average latency He. (f) (weeks) fd) c- Avera^e "-J to Ho. J (f) latency time (weeks) (a) 0- - 1 0j - (weeks) fdl i \ --i 0- - i 10C.0 65.0 0- oj - i --i i 0- - i 100.0 65-0 0- ---------- f---------- - 0| - -- 1il 0 - 0J 0 - - oj - 0- - 0- i 5 3.7 69.5 5 2.0 69.5 1 .0 1.0 5 j 100.0 5 j 100.0 0j 0j - - 4 j 0.0 71 .7 j 0 7U7 'j 0 - - 4 80.0 - 1 20 J 61.2 - 1 20.0j *51.0 ' V SL 082942 cn C o CP to CD *> OJ \ TABLE 8 v0 stu*0 y-\ rintent BT502- : Exposure By inhalation to Dichloroethane in air at 250-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. DISTRIBUTION OF THE DIFFERENT TYPES OF MISCELLANEOUS ("OTHER") TUMOURS GROUPS NO. SEX . * I 9 0* II 40 40 III 0* 9 IV 0* 0* V 9 o ^*4 ANIMALS BEARING OTHER TUMOURS Benign Malignant Distribution of histotypes No. Distribution of histotypes 0 1 1 subcutaneous angiosarcoma 1 1 spleen angioma 0 Total 1 1 0 1 1 ovary leiomicna 0 1 1 peritoneal angioma 1 1 adrenal gland cortical carcinoma 2 1 Karderian gland adenocarcinoma 1 granulosa cell- tumour of the ovarj 1 1 subcutaneous fibrosarcoma 1 1 fibrosing linosarcoma 1 3 1 2 0 0 3 2 hepatomas 1 spleen angioma 0 0 1 1 skin squamous carcinoma 0 2 1 skin squamous carcinoma 1 intestinal fibrosarcoma 0 1 3 2 TABLE 8 (follows) ,\ogse \0 Experiment BT502 : Exposure by inhalation to Dichloroethane 'in air at 250-150, 50, 10, 5 ppm, 7 hours daily, 5 days weekly, for 78 weeks. Results after 104 weeks. -- GROUPS NO. SEX DISTRIBUTION 0? THE DIFFERENT TYPES OF MISCELLANEOUS ("OTHER") TUMOURS ANIMALS BEARING OTHER TUMOURS Benign Malignant No. Distribution of histotypes No. Distribution of histotypes Total 0* 1 1 hepatoma VI 00 T 0 0 0 0 V 0* 4 3 hepatomas 1 spleen angioma and VI $0 0 2 1 skin squamous carcinoma 1 intestinal fibrosarcoma 4 2 SL 082944