Document ev4keOE06VEGNrJmNKGbqnrL4

Chlorobiphenyle (PCBs) In Wisconsin Natural Waters Oilman D. V.ith Wstsr Chemistry Program Department of Civil and Environmental Engineering University of Wisconsin Madison, Wisconsin 53706 ABSTRACT The seizure of fish from Lake Michigan because of the presence of ohlorlnated pesticides and PCBs at concentrations which are greater than that regarded as safe for human consumption has demonstrated that the continuous input of trees quantities of these ohemleals nay Jeopardies major food resources for man. Recant svidsnee has indicated that the ratio of the FCB concentration in fish to that in the water near the sits of capture is on the order of 100,000, although the ratio may vary by more than an order of magnitude. The magnitude of thle ratio suggests that the concentration of PCBs in fish from water containing greater than 0.05 pg/l PCBs may exceed the 5 Pg/gm action limit established for fish. Investigations by the Water Chemistry Program and the Wleconsin Depart ment of Natural Resources have shown the PCBs are present in the wastes from all municipalities examined. The concentration of PCBs in the re ceiving waters for sanitary wastes alone seldom exceeded 0.10 pg/l, whereas the discharge of industrial wastes containing PCBs either directly or in municipal waste effluents resulted in concentrations greater than 2 pg/l (as Aroolor 1266), Efforts to determine the major sources and current levels of PCBs in ths Cresn Bay area of Lake Mlohlgan have shown that the concentrations of PCBs varied from below the determinable limit of approximately 0.01 pg/l (20 liter water sample) in rivers such as the Big Suamlco which drain agricultural and forested areas and receive no municipal wastes to 0,45 pg/l (as Aroolor 1256) in the receiving streams for industrial and municipal wastes. The mixtures of PCBs In municipal wastes generally resembled Aroolor 1248 or 1258 although the earlier eluting isomers of Aroclor 1262 were often observed. The oonoentratlon of FOB mixtures resembling Aroclor 1256 in the Pestigo and Oconto Rlvere were 0.31 and 0.65 pg/l, respectively, in November, 1970| O.38 and 0.16 pg/l, respectively, in April, 1971 but 'decreased to near or below the detectable limit during the summer of 1971. The oonoentratlon in lower Green Bay water varied from 0.06 pg/l at Sturgeon Bay to 0.07 pg/l near Longtall Point. Further study is required to deter mine if the restricted use of PCBs In industry will lead to a pronounced deorease of the oonoentratlon of the chemicals in waste effluents and in nearshore environments such as Green Bay. MOWS 060962