Lethality of a suspended clay to a diverse selection of marine and estuarine macrofauna.

In this investigation, an evaluation was made of the lethality of suspended clay mineral texturally representative of the sediment-size fraction with which contaminants are most commonly associated. The study involved a phylogenetically diverse selection of marine and estuarine macrofauna. The time-concentration mortality response of 16 species of fish and invertebrates indicated widely differing sensitivities to high concentrations of clay suspended in the water. Organisms restricted to muddy bottoms were found to be very insensitive to high suspended clay concentrations. However, some open water fish, fouling organisms, and sandy bottom epifauna were found to be relatively sensitive. Tolerant species were also identified from these groups.