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Sewage sludge may contribute more than 10% of total loadings 

 for two toxicants. At least in the recent past, this appeared 

 to be true for PCBs. A second possible exception is DDT and 

 its metabolites; however, there are insufficient data on the 

 total loadings of this family of compounds to be certain of the 

 relative contribution of these materials made by sewage sludge. 

 During the late 1970s, ocean-dumped sewage sludge was estimated 

 to contribute roughly 30% of the total PCB loading in the New 

 York Bight, with dredged materials contributing approximately 

 70%. (Some fraction of the PCBs in dredged materials is 

 probably sequestered in the dumpsite mound.) Recent information 

 suggests that decreased PCB usage in the late 1970s may now be 

 reflected in lower PCB levels in municipal sewage sludges. The 

 City of New York recently analyzed PCB levels in sewage sludge 

 samples from 12 New York City sewage treatment plants. The 

 range of average concentrations for these 1982 samples was 

 0.56 - 2.88 micrograms per gram, i.e., five parts per million, 

 dry weight. If these PCB values are representative of all 

 19 New York-New Jersey sewage sludges, the mass loading of 

 PCBs in the New York Bight Region from ocean-dumped sewage 

 sludge may now be comparable to that of other contaminants 

 in these sludges (i.e., within the 1-12% range). 



PCBs have been found in tissues of fish which live totally 

 within the Bight Apex as well as in migratory forms taken up 

 to 200 kilometers offshore. Concentrations in organisms 



