A survey of sediment toxicity was carried out by NOAA's National Status and Trends Program in Long Island Sound in New York and Connecticut. The survey objectives were to determine the spatial distribution and severity of toxicity and chemical contamination in the sediments.
Sixty-three sediment samples were tested for toxicity with three independent
protocols:
(1) a 10-day amphipod survival test of the whole solid-phase sediments with Ampelisca
abdita,
(2) a 48-hour exposure of clam larvae, Mulinia lateralis, to sediment
elutriates, with normal development and survival as the endpoints, and
(3) a microbial bioluminescence test (Microtox™) using solvent
extracts of the sediments. Separate samples from these same stations were analyzed
chemically for a broad suite of potentially toxic contaminants.
The survey results indicate that sediment toxicity is widespread in the coastal bays of Long Island Sound. Significant toxicity was indicated for the sediments from at least one of the stations in each of the 20 coastal bays sampled in this survey. Only 11 of the 60 stations showed no significant toxicity in any of the three tests. About one-fifth of the total area (79 km2) sampled was indicated as significantly toxic by all three tests (survival of amphipods and larval bivalves, and Microtox™).
