Document QXbMgg67Z9wB0Gx880D1oQRn6

Ifrnsaiito '* (?c&- TCDP R.PltOK IN4MI LOCATION I E> Keller - .Technology Department - South Second Sfcrgafr OATI UBJCCT TO i October 20,` 1970 . e u r a n s i n Ar o c l o r p r o d u c t s i : W. B. Papageorge General Offices * - ce. W . R. Richard - GO M. ' I t . Farrar - Res. H. S. Bergen - GO P. Wheeler ? GO M. w. Dietrich - Res E. M. Emery - Res. 2 E. S. Tucker - Res. R. H. Munch - R es. 2 J. P. Mleure - Res. The attached report by Dr. Mleure shows that Aroclor 1242, 1242D, 1254 and 1260 Contains no detectable polychlorinated dlbenzofurans Aroclr 5442 contains: detectable tetrachlorodibenzofuran at 1-3 ppm. Competitive Prodelec Phenoclor DP6 contain*' considerably more dlbenzof urans On this basis., the Aroclor 1200 series sent for feeding studies at 'Bio-Test appears free ( < 1*5 ppm) of furan contaminants which might bias the results. It will be noted, however, that these products do contain varyitig amounts of polychlorinated naphthalenes. Woul^ toxicity results from feeding studies be affected by these Impurities? 1* i Polychlorinated anthracene or phenanthrene and tetrachloro- dlbenzofuran impurities found In Aroclor 5442 probably explain why the National Water Quality Laboratory at Duluth, Minnesota finds that Aroclor 5442 is much more toxic to Daphnla than any of the PCB's. The report doesn't mention It, but no polychiorodlbenzo-pdioxins were found in any of the products. The detection limit is an estimated 1-5 ppm depending on the specific impurity and product Involved. . tv db Attachment R.. E. Keller * \* NEX 0368^9