Relationship of per cent mortality of four species of aquatic biota from 96-hour sediment bioassays of five Lake Michigan harbors and elutriate chemistry of the sediments

Forty sediment grab samples were taken from Lake Michigan in 1977 to determine the effect of dredge spoil disposal on sediment toxicity. Bioassays conducted with the sediments indicate that mortality rates of organisms exposed to the sediments increased in 25 of 88 instances. The use of the elutriate test for evaluating the possible toxicity of dredged material disposal is suspect, because the test only simulates the immediate impact of material on the aquatic environment. (4 graphs, 10 references)