Document JNMDmJba07jEm9Rvn7mE12Yv6

',,.A/ w. -- d i. l n ea is try Special Study 70-17 Job No. 1343046 DETERMINATION OF POLYCHLORINATED BIPHENYL RESIDUES IN RATS ________ PROM 30 DAY AROCLOR FEEDING STUDIES INTRODUCTION One of the more significant objectives of the Aroclor - Environment program has been to develop a more complete picture of what occurs to Aroclor products once they are released to the ecosystem. The importance of this information is two fold, first it can be used to guide the development of a more "degradable" Aroclor product and secondly, the general methods developed to study the current Aroclor products can be used to determine the degree of control that must be exercised over the replacement products to avoid similar problems with these materials in the future. As a part of achieving this overall objective, Industrial Bio-Test Laboratories was requested to carry out a 30 day tissue collection study in albino rats with Aroclor 1242, Aroclor 1254 and Aroclor 1260. This report deals with the subsequent analysis of these tissues for residual PCB's. The details of tissue collection study can be found in the Industrial Bio-Test report, IBT No. B7009. A copy of this report is attached. SUMMARY The results of this study demonstrate that the residual PCB levels in all tissues decreased significantly as the degree of chlorination and the dietary exposure level of the material fed decreased. Additionally, it was observed that the amount of isomeric alteration Increased as the degree of chlorination decreased resulting in the fact that the major PCB isomers retained by the rats fed Aroclor 1242 were those predominantly present in Aroclor 1254 and Aroclor 1260. There were no significant differences in the type of isomeric alteration from tissue to tissue or between sexes. RESULTS The experimental data supporting the conclusions are shown in Tables I - III, and in Figures I - VIII. DISCUSSION All tissue samples were analyzed as outlined in Analytical Chemistry Method No. 70-1 and the PCB levels estimated using the Aroclor fed as the standard. Upon completion of the electron capture (EC) wor all tissue extracts, for each Aroclor fed, were combined and con centrated. The concentrates were then further purified via liquid chromatography on alumina and subjected to high resolution gas PLAINTIFF'S EXHIBIT Ai/i* 0055 Special Study 70-17 Page 2____ ________ chromatography on a support coated open tubular (S.C .0.T .)'column in an attempt to identify aa many of the remaining Isomers and homologa aa possible. The EC chromatograms (Figures I-III) Included in this report are representative of those obtained for each tissue (muscle, liver, kidney, and fat) and each Aroclor. For Aroclor 1242 the dominant FCB homologs retained are peak numbers, 8(trl); 10, 13, lA(tetra); 15, 16(penta); 20, 22(hexa); and 26(hepta). With Aroclor 1254 they are, 15(penta); 20, 22(hexa); and 26(hepta) and vlth Aroclor 1260 they are, 20, 22(hexa); 26, 27(hepta); and 28, 29, 30(octa). The fact that peaks 10, 13, 14, 15 and 16 are present in Aroclor 1242 extracts but not as dominant in Aroclor 1254 and Aroclor 1260 extracts seems to indicate that if the Aroclor 1242 dietary exposure level were reduced sufficiently these homologs would also be metabolized-and/or excreted as they were with Aroclor 1254 and 1260. The very refractory homologs appear to begin with peak #20 in the penta-hexachlorobipheny1 region. EC chromatograms of fractionated Arocljor 1130 and HCS 1016 (Figure IV) are included for comparison purposes. From these, it can be readily seen that these materials are a marked Improvement over Aroclor 1242 in that they contain no observable amounts of the homologs that build up. The S.C.O.T. column chromatograms (Figures VI-VIII) of the concen trated extracts are even more instructive in that the greater separation power of the column allows the identification of some of the PCB isomers that are not retained. For example, only traces of the following biphenyl isomers, dominantly present in the material fed remain: 2-chloro; 3-chloro; 4-chloro; 2,6dichloro; 2,4-dichloro; 2,5-dichloro; 2*3'-dichloro; 2,4 *-dichloro; 2,5,2'-trichloro; 3,3*-dichloro; 3,4-dichloro; 3,4*-dichloro; 4,41-dichloro; 2,3,2*-trichloro; 3,4,2'-trichloro and 2,3,4'trIchloro. The S.C.O.T. column chromatograms (Figure IX) of the proposed substitutes are again included for comparison purposes. db Monsanto Company Organic Chemicals Company Applied Sciences Section St. Louis, Missouri 9/70 - W. J. Litschgi, B. J. Westenberger, E. S. Tucker AO* U0559 S ESTIMATED PCB CONTENT OF RAT TISSUES Tes t Dietary Compound Sex Level AR0CL0R 1242 H F 300 300 H 1000 F 1000 FAT ppm Found Wet Wt Lipid Wt ---- 276 395 377 816 412 722 AROCLOR 1254 M 300 F 300 M 1000 F .1000 695 660 6660 3430 1094 1289 7208 7544 AROCLOR 1260 M F 300 300 2130 2035 3061 3430 M 1000 9190 13715 F 1000 11970 19088 KIDNEY PPm Found Wet Wt Lipid Wt 1.40 2.30 5.00 2.30 12.4 28.1 276 146 7.90 12.9 46.6 156 655 1895 3325 12972 28.8 16.0 72.5 91.0 2056 2671 5181 7579 LIVER ppm Found Wet Wt Lipid Wt 2.70 4.60 10.5 17.4 60.6 220 753 793 56.9 53.7 176 227 2370 3358 5318 6678 126 3808 125 6226 200 6263 206 10300 MUSCLE ppm Found Wet Wt Lipid Wt 5.00 12.2 16.9 29.0 37.3 58.3 736 855 55.8 36.0 271 167 1396 1274 7 735 6202 81.6 136 266 555 2470 4849 8879 24111 ADM 005598 TABLE II ELECTRON' CAPTURE GAS CHROMATOGRAMS Chromatographic Conditions Instrument: Hewlett-Packard Model 402 Type Detector: N1&3 Electron Capture Column: 6 T X 4 mm glass U, 42 XE-60 on 80/100 Mesh Chromosorb V, HP Column Temperature: 200 0C Detec tor Temperature: 300 C Inj ection Fort Temperature: 220*C Carrier 60 ml/min Purge 120 mi/min Electron Capture Peak 1 2 3 4 5 6 7 6 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Dominant Homolog as Identified by Aroclor Aroclor Arocl 1242 1254 1260 1 1223333344 44 44 44 45 -5 -5 -5 - 6 -6 -6 -6 -6 ----- -- -- --- -- - \- _ - -- -- - - - -- - -' - 5 5 6 6 6 6 6 6 7 7 7 7 7 8 8 8 8 ADM O055r A DM 00 5 ADM 00 5l ADM 005602 A .i / / S \ ADM 0050 TABLE III FFAP S.C.O.T. COLUMN CHROMATOGRAMS Chromatographic Conditions Instrument: Perlcin-Elmer Model 800 equipped with a .30/1 sample inlet splitter Type Detector: Flame Ionization Column: 100' X .02" FFAP S.C.O.T. Column Column Temperature: 235*C Detector Temperature: 260*C Injection Port Temperature: 340*C Carrier Gas - Helium @ 15# FFAP S.C.O.T. Column Peak Wo. 1 2 3 A 5 6 7 8 9 10 11 12 13 1A 15 16 17 18 19 20 21 22 23-26 27 28-37 38 39-A2 43-49 Compound As Identified by Retention Time Biphenyl 2,6 2, 2' 2,A 2,5 2,3' 2, A' 2,5,2 3,3' 3,A 3,A' A,A' 2,3 2' 2 ,5,A* 3,A , 2 ' 2,3,4' 3,A,A' Humber of Chlorines 0 1 1 1 2 2 2 2 2 2 3 3 2 2 2 3 2 3 3 3 3 3 3 3 A 3 A 5 I ADM 0G560^  AM OC 5b  I 3 t .t. )QOO WTV' ' S