Document X7gQ9agyEYq7qqG0advqjk4xB

i July 18, 1975 Dr. J.C. Calandra Industrial BIO-TEST Laboratories 1810 Frontage Rd. Northbrook, 111. 60062 ' ,,/ V' V re: AROCLOR 2-year Rat Feeding Studies Dear Joe: The attached table-njummarizes a comparison of the 3 revised AROCLOR reports ((1242^ 1254, 126o). In 2 instances, the previous conclusion of ''slightly tumorigenic" was changed to "doea not appear to u carciiiogenle". The latter phrase is preferable. May vie request that the AROCLOR 1254 report be amended to say ''does net appear to be carcinogenic". The number of hepatomas reported for AROCLORS 1260 and 1242 have been interchanged. This appears to have arisen from con fusion regarding the numbering of the animals. The original reports show tumors in animals viith numbers In the 100-300 range for AROCLOR 12o0 and In the 500 to 800 range for AROCLOR 1242. This leads me to conclude that the numbering scheme shown in the second set of reports is correct. With AROCLOR 1254 confusion is compounded. The original report showed tumors in animals with numbers In the units to teens, but the revised report shows animal numbers ranging from 40 to 1000. Can this be straightened out? I was unable to reconcile the differences in the animal numbers between the first supplemental report and the original reports, I had inquired as to the changes in the numbers. As I recall', I was told that the sections had been renumbered when the new slides were made and that a key relating to the sets of numbers OSIN M*40 STLCOPCB4091157 Dr. J.C. Calandra July 18, 1975 Page ** 2 * would be supplied. This has not been done. It may not be necessary for ABOCLORS 1260 and 1242, but AROCLOR 1254 remains unresolved. Insofar as I can see, the remainder of the reports appear acceptable. Kindest personal regards. Sincerely, George J. Levinskas, PhD Mgr., Environmental Assessment and Toxicology /blcp att. ec; Dr. George 'Roush, Jr., M.D. OS'N 55274A STLCOPCB4091158 Product Supplemental Report #1 (mailed) AROCLOR 1260 . conclusion slightly tumorigenic hepatomas 3 range of test animal nos: p. 9 0. 10 p. 11 p. 12 p. 13 p. 14 600 to 800 1000 series 70 to 100 500 to 600 600 to 700 700 series Supplemental Report #2 (JCC delivered) does not appear carcinogenic 7 ICO to 300 8OO to 900 lotto 4o 80 to 200 200 to 300 200 to 300 AROCLOR 1254 conclusion hepatomas slightly tumorigenic 6 slightly tumorigenic 6 AROCLOR 1242 conclusion slightly tumorigenic does not appear carcinogenic hepatomas range of test animal nos. 73 as In report #2 as in report #1 for AROCLOR 1260 AROCLOR 1260 qSVM 552742 STLCOPCB4091159