PCBs IN THE HUDSON RARITAN ESTUARY PCBs, found in varying concentrations in sediments and biota throughout the region, impair the coastal resources of NY and NJ by limiting the consumption of fish from local waters as well as creating a challenge for disposing of dredged materials from rivers, harbors, and bays.
Until the mid 1970s, PCBs (polychlorinated biphenyls) were sold and used commercially in numerous industrial processes due to attractive properties such as non-flammability and strong resistance to chemical, physical and biological decay. It is this same quality that causes their pervasiveness in the environment today. Residues of commercial PCBs persist in the waters, sediments and biota of the Hudson Raritan Estuary including the Passaic and Hackensack Rivers of New Jersey and they can be found in the waters and sediments of coastal bays and harbors. This is a concern, as PCBs are popularly viewed as carcinogenic, though their precise human and animal health risk has yet to be determined.
In sediments, PCBs tend to bind to the finer grained particles such as clays and silts which constitute much of the material to be dredged from regional waterways. As a result, disposal of dredged materials becomes much more complicated. Ocean disposal at the historic mud dump site 6 miles off of Sandy Hook (now HARS) is restricted to materials under 113 parts per billion, total PCBs, however this standard is currently under rulemaking review.
In biota, PCBs are lipophillic meaning that they tend to accumulate in the fatty tissues. PCBs enter small fish in a number of ways including through gills and consumption of flora. As a result, fish at the top end of the food chain bioaccumulate the PCBs present in the smaller fish that they eat. Consumption of such fish can then accumulate PCBs in humans. As a result, numerous restrictions have been placed on the consumption of certain fish and game species.
Although also produced inadvertently in a number of industrial processes, PCBs were marketed as a commercial product exclusively by the Monsanto Corporation under the trade name Aroclor. Different classes (or homologues) of Aroclors are distinguished by their weight and level of chlorination the heavier, more highly chlorinated Aroclors also tend to be the most resistant to breakdown while the lighter variants tend to breakdown, volatilize (evaporate) more easily and bioaccumulate less readily. PCBs produced inadvertently in industrial processes are for the most part exempt from regulation under the Toxic Substances Control Act (TSCA) and under current industrial testing methodologies are often not detected.
At present, regulatory standards do not differentiate between types (or congeners) of PCBs rather standards are set for total PCBs. The New York State Clean Water Standard for PCBs is 1 picogram per liter, or one part per quadrillion. Currently, NYSDEC is investigating the potential for different regulatory standards for different classes of PCBs, however only one toxicologist is assigned to this task. A more rational approach towards regulation of PCBs might be to differentiate between congeners based on their behavior in the environment.