GROWTH AND SURVIVAL OF 3 MARINE INVERTEBRATE SPECIES IN SEDIMENTS FROM THE HUDSON-RARITAN ESTUARY, NEW-YORK

Sediments in the Hudson-Raritan estuary are known to contain high conc entrations of anthropogenic contaminants, and marine organisms from th is region exhibit numerous contaminant-related effects. To assess the pattern of sediment toxicity in depositional areas of this region, and to compare lethal and sublethal end points for different bioassay org anisms, three benthic marine invertebrate species were exposed to sedi ments from 17 sites in the Hudson-Raritan estuary. Growth and mortalit y of the polychaete Armandia brevis and the sand dollar Dendraster exc entricus were measured in all 17 sediments, while mortality and reburi al ability of the amphipod Rhepoxinius abronius were assessed in nine sediments. Growth of polychaetes was determined by measuring the diffe rence in weight after a 20-d exposure, whereas growth of sand dollars was assessed by measuring the difference in length and weight after a 28-d exposure. Amphipod mortality and reburial tests were conducted us ing the standard 10-d sediment bioassay. Significant growth reduction of polychaetes and sand dollars occurred in 11 of 17, and 3 of 17 sedi ments, respectively. Polychaete weight and sand dollar length correlat ed inversely and significantly with total sediment concentration of po lycyclic aromatic hydrocarbons, polychlorinated biphenyls, and some se lected elements. In contrast, significant mortality of polychaetes and amphipods occurred in 1 of 17 and 2 of 9 sediments, respectively, and impaired reburial ability of amphipods was not observed. Results of t his study demonstrate that sediment contamination at depositional site s with the Hudson-Raritan estuary has potential to cause deleterious b iological effects in indigenous benthic organisms. In addition, sublet hal growth bioassays using polychaetes and sand dollars appear to be m ore sensitive in measuring the effects of sediment contamination than does the mortality-based bioassay using the amphipod Rhepoxinius abron ius.