In December 1989, the National Marine Fisheries Service (NMFS) collected sediments from 19 loca- 

 tions in the estuary and tested them for toxicity with the Microtox 1 ™ bioluminescence test (DeMuth et 

 al, 1993). Tests were performed with three types of extracts: (1) saline solution extracts; (2) sequential 

 saline and organic extracts; and (3) organic extracts. Duplicate tests were performed with most samples. 

 The effective concentrations (EC50s) that caused 50% reductions in light output were determined for 

 each of the three tests. 



As judged by the lowest EC50 values, the Microtox tm tests indicated that the sediments from Newtown 

 Creek (a tributary of the lower East River); Throg's Neck (upper East River); and Shooters Island 

 (Arthur Kill) were among the most toxic (Table 10). Samples from Rockaway Bay, Fall Hook Chan- 

 nel, Ambrose Channel, and Jamaica Bay were the least toxic in the Microtox tm tests. 



Table 10. Results of microbial bioluminescence (Microtox tm ) tests of sediments from the Hudson- 

 Rartian estuary performed with three kinds of sediment extracts (from DeMuth et al., 1993). 



a Results of tests performed with saline extracts, reported as the amount of sediment equivalents (g) that 



decreased light output by 50%. 



D Results of tests performed with organic extracts previously extracted with saline solution, reported as 



amount of sediment equivalents (ug) that decreased light output by 50%. 



c Results of tests performed with organic extracts, reported as the amount of sediment equivalents (wg) 



that decreased light output by 50%. 



Polychaete and Sand Dollar Growth Tests. In 1991, the NMFS (Rice etal., in press) tested 17ofthe 

 117 samples collected in Phase 1 of the present survey (Table 11). In these samples, impaired growth 

 was measured among polychaetes (Armandia brevis) and adult sand dollars (Dendraster excentricus). 

 Both species were collected from Puget Sound for the tests. Significant reductions in growth were 

 quantified by comparisons of the data with animals exposed to unspecified controls. The sediments 



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