Document jND5kXOBDvY7GDn7dLrJ6Jw8R

4 Ai/lytical Chemistry Special Study 70-17 Job No. 1348046 DETERMINATION OF POLYCHLORINATED BIPHENYL RESIDUES IN RATS __________ FROM 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-Tid* Laboratories was requested to carry out a 30 day tissue collection study In albino rats with Aroclor 1242, Aroclor 1254 and Aroclof 1260. This report deals with the subsequent analysis of these tissues for residual PCB's. The detalla of tiasue 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 analysed 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) work ell 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 l MOMS 067684 .0 Special Study 70-17 Page 2_ chromatography on a aupport coated open tubular (S.C.0.T.) 'column in an attempt to Identify aa many of the remaining lsomera and homologa aa possible. The EC chromatograms (Figures I-III) Included in this report are repreaentatlve of those obtained for each tissue (muscle, liver, kidney, end fat) and each Aroclor. For Aroclor 1242, the dominant PCS bomologs retained are peek numbers, 8(trl); 10, 13, 14(tetra); 15, 16(peiita); 20, 22(hexa); and 26(hepta). With Aroclor 1254 they are, 15(penta); 20, 22(hexa); and 26(hepta) and with 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 peakv#?0 in the penta-hexachlorobiphenyl region. EC chromatograms of fractionated Aroclor 1130 and MCS 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; 2,6- dlchloro; 2,4-dichloroj 2,5-dichloro; 2,31-dichloroj 2,4'-dichloro 2,5,2'-trichloro ; 3,3'-dichloro; 3,4-dichloro; 3,4'-dichloro; 4,4 -dichloro; 2,3,2'-trichloro; 3,4,2-'-trichloro and 2,3,4'- trlchloro. - 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. Lltschgl, B. J. Weatenberger, E. S. Tucker HONS 0676*5 TABLE X ESTIMATED ?CB COHTEWT Of BAT TISSUES w Teat Dietary Compound Sex Level AROCLOR 1242 M F M P 300 300 1000 1000 BAT ppa Found Wet Vt Lipid Wt - 276 377 A12 - 395 816 722 BXDBBT PP Found Vet Wt Lipid Vt 1.40 2.30 5.00 2.30 12.4 28.1 276 146 AROCLOR M . 300 F 300 M 1000 F 1000 695 660 4660 3430 1094 1289 7208 7544 7.90 655 12.9 1895 . 46.6 3325 156 12972 AROCLOR 1260 N F M F 300 300 1000 1000 2130 2035 9190 11970 3061 3430 13,715 19088 28.8 16.0 72.5 91.0 2056 2671 5181 7579 LIVER ppn Found Vet Vt 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 126 125 209 206 3808 6226 6263 10300 MUSCLE PP Found Wet Vt Lipid Wt 5.00 12.2 15.9 29.0 37.3 58.3 736 855 55.8 36.0 271 167 1396 1274 7735 6202 81.6 136 266 555 2470 4849 8879 24111 o , TABLE IX vJ ELECTRON CAPTURE GAS CHROMATOGRAMS Chromatographic Conditions Instrument: Hewlett-Packard Model 402 Type Detector: Ni63 Electron Capture Column: 6' X 4 mm glass U, 41 XE-60 on 80/100 Mesh Chromoaorb W, HP Column Temperature: 200*C Carrier - He, 60 ml/mln Detector Temperature: 300*C Injection Port Temperature: 220*C Purge - Ar/CH L (g/D m 1/mln Electron Capture Peak 1 2 3 4 3 6 7 8 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 CC/MS Aroclor Aroclor Aroclor 1242 1254 1260 1 1 2 2 3 3 3 3 3 44 44 44 44 4 55 55 5 56 66 66 66 66 66 7 7 7 7 7 8 8 8 8 HONS 067687 HONS 067689 .0 o P~itu*e 77" MGNS 067691 TABLE XII FFAP S.C.O.T. COLUMN CHROMATOGRAMS Chromatographic Conditions Instrument: Perkin-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: 280*C Injection Fort Temperature: 340*C Carrier Gaa - Helium 8 15# FFAP S.C.O.T. Column Peak Ho.; 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 .21 22 23-26 27 28-37 38 39-42 43-49 .. . Compound As Identified by Retention Time! Biphenyl 2 3 4 2.6 2,2' 2,4 2.5 2.3' 2.4' - 2.5.2* 3.3' 3.4 3.4' - 4.4' 2.3,2' 2.5,4* - . 3,4,2V - - . 2,3,4* - 3,4,4* - - Number of Chlor: 0 1 1 1 2 2 2 2 2 2 3 3 2 2 2 3 2 3 3 3 3 3 3 3 4 3 4 5 HONS 0* 1 .0 o HONS Q676'3 HONS 0 6 7 6 9 4 ! 94 o MONS 0 6 7 6 9 6