Document 105eLa6D58X63VDN6DX5dvp1K

Chlorobiphenyls (PCBs) In Hleconoin Natural Haters Gilman D. Velth Hater Choaiatry Progran Department of Civil and Environmental Engineering University of Wisconsin Madison, Vloconain 53706 ABSTRACT The seizure of fish from lake Michigan because of the presence of chlorinated pesticides and PCBs at concentrations which are greator than that regarded as safe for human consumption has demonstrated that the continuous input of trace quantities of these chemicals say Jeopardise major food resources for nan. Recent evidence has indicated that the ratio of the PCB concentration in fish to that in the water near the site of capture is on the order of 100,000, although the ratio may vary by mere than an order of magnitude. Tho magnitude of this ratio suggests that the oonoentratlon of PCBs in fish from water containing greater than 0.05 pg/l PCBe may exceed the 5 ug/g action limit established for fish. Investigations by the Hater Chemistry Program andths Wisconsin Depart ment of Natural Resources have shown the PCBs are present in tho wastes from all municipalities examined, The concentration of PCBe in the re ceiving waters for sanitary wastes alono 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/i (as Areolor 1248), Efforts to detormine the major sources and ourrent levels of PCBs in the Green Bay area of lake Michigan have shown that the concentrations of PCBs varied from below the detoralnablo limit of approximately 0.01 pg/l (20 liter water sample) in rivers such as tho Big Suamlco which drain agricultural and forested areas and receive no municipal wastes to 0,45 jig/l (as Aroclor 1254) In the receiving streams for Industrial and municipal wastes. The mixtures of FCBa in municipal wastes generally resembled Aroclor 1248 or 1258 although the earlier olutlng leomers of Aroclor 1242 were often obeerved. The oonoentratlon of FCB mixtures resembling Aroclor 1254 in the Peatigo and Oconto Rivera wars 0.31 and 0,45 ng/l, respectively, in November, 1970| 0,38 and 0.16 jig/l, respectively, in April, 19711 but deereaaod to near or bolow the detoctable limit during the summer of 1971, The concentration in lowor Croon Bay water varied from 0,04 ug/l at Sturgeon Bay to 0,07 pg/l near Longtail Point. Further study is required to deter mine if the restricted use of PCBs in industry will lead to a pronounced deoreaee of the concentration of the chemicals in waste effluents and in nearshore environments ouch as Greon Bay, MOMS 0713?6