In 1988 it was estimated that 6.8 million gallons per day of untreated sewage was discharged into the 

 estuary, primarily from Manhattan, Staten Island, and Brooklyn (Gottholm et al., 1993). With the 

 implementation of better source controls at key sewage treatment plants, the rate of discharge from the 

 city of New York decreased to less than 1.0 million gallons per day by 1992. 



Over 1,453 accidental incidents, resulting in the release of more than 18 million U.S. gallons of hazard- 

 ous materials and petroleum products, occurred throughout Newark Bay between 1982 and 1991 (Gunster 

 et al., 1993). The majority of these spills consisted of petroleum products, including fuel oils and 

 gasoline. Many of them occurred in the lower Passaic River, Arthur Kill, Newark Bay, and Kill van 

 Kull. 



Data collected by numerous investigators, including the National Status and Trends Program, have 

 indicated that the concentrations of many potentially toxic chemicals are highly elevated in the Hudson- 

 Raritan Estuary. The objectives of this report are to describe the magnitude (severity, multiplicity, 

 incidence) of toxicity, the spatial patterns of toxicity, the spatial extent of toxicity of sediments, and the 

 relationship(s) between sediment toxicity as a measure of toxicant-associated biological effects and 

 potentially toxic substances. 



Contaminant Concentrations. Many different assessments have been conducted to determine the 

 presence, concentration, and distribution of toxic chemicals within the estuary. These assessments 

 have been performed by many independent investigators and have shown that toxicants occur through- 

 out the estuary in mixtures that differ from place to place. The toxicants that occur above background 

 levels include PCBs, PAHs, DDT, other pesticides, many trace metals, radioisotopes, dioxins and furans. 

 It is not the purpose of this report to review the results of all of these efforts. Several excellent reports 

 summarize the data on concentrations and distributions of toxicants in the Hudson-Raritan Estuary 

 (e.g., Olsen et al., 1984; Breteler, 1984; NOAA, 1988a; Bopp and Simpson, 1989; Squibb et al., 1991; 

 City of New York, 1987; Huntley et al., 1993; Bonnevie et al., 1993; New York-New Jersey Harbor 

 Estuary Program, 1995). 



Based upon the available data from these many studies, several generalized patterns are apparent in the 

 distribution of elevated concentrations of toxicants. These generalities are tempered by many observa- 

 tions of heterogeneity attributable to patchiness in sediment properties, sedimentation rates, scouring, 

 dredging, and proximity to sources and other processes that influence the fate of toxicants. Neverthe- 

 less, areas in which relatively high concentrations of different toxicants have been observed frequently 

 include Newark Bay, Arthur Kill, lower Passaic River, lower Hackensack River, Gowanus Canal, west- 

 ern Raritan Bay south of Staten Island, and the bays adjoining the upper East River/western Long 

 Island Sound. Intermediate levels of many toxicants often have been reported for parts of central 

 Raritan Bay, upper New York Harbor, lower Harlem River near Ward's Island, and the lower Passaic 

 River. Relative to these areas, toxicant concentrations often have been lowest in lower New York 

 Harbor south of Coney Island and northwest of Sandy Hook, the East River, Harlem River, lower 

 Hudson River, and eastern Raritan Bay. 



Extremely high concentrations of dioxins and furans in sediments and marine biota have been reported 

 for the lower Passaic River (Pruell et al., 1990; Bopp etal., 1991;Tongetal., 1990; Beltonetal., 1985). 

 The concentrations of these compounds gradually diminish downstream into Newark Bay and New 

 York Harbor. In addition, the concentrations of PAHs and many trace elements were found in very high 

 concentrations in samples collected in the lower Passaic River, lower Hackensack River, and Newark 

 Bay (Huntley et al., 1993; Bonnevie et al., 1993). 



