Document oDGvgp2nXVzLvJQDY1Bge8Z4o
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Monsanto
MoflltntS Comgiity 800 N. Lindbtrgft louUvtrd St. louii. Umouri 83108 Fton: '314! 194-1000
July 18, 1975
Dr. J.C. Calandra Industrial 310-TEST Laboratories 1310 Frontage Rd.
Northbrook, 111. 60062
re: AROCLOR 2-year Rat Feeding Studies
Dear Joe:
The attached table summarizes a comparison of the 3 revised.
AROCLOR reports (1242, 1254, 1250).
'
In 2 instances, the previous conclusion of "slightly tumorigenic" was changed to "does not appear to be carcinogenic". The latter phrase is preferable. May we request that the AROCLOR 125report 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 with numbers in the 100-300 range for AROCLOR 1260 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. Vith 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
received
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Dr. J.C. Calandra July 18, 1975 Page - 2 would be supplied. This has not been done. It may not be necessary for AROCLORS 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. Levlnskas, PhD Mgr., Environmental Assessment
and Toxicology /bkp att. cc: Dr. George Roush, Jr., M.D.
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Product
Supplemental Report #1 (mailed)
AROCLOR 1260
.
conclusion
slightly tumorigenic
hepatoma* s.
t*
t
3
range of test animal nos:
p. 9 p. 10
600 to 800 1000 series
p. 11
70 to 100
p. 12
500 to 600
P. 13 p. 14
600 to 700 700 series
Supplemental Report #2 (JCJ delivered)
does not appear carcinogenic
7
100 to 300 800 to QOO
lOtto 40 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 noa.
7
3
as in report #2 as in report #1 for AROCLOR 1260 AROCLOR 1260
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