The investigator proposes to develop a project to examine the effect of chronic exposure to low-level concentrations of pesticides and their interaction with other environmental factors on the growth, reproduction and respiration of marine and freshwater crustaceans. Of particular interest would be the combined effect of pesticides and environmental factors such as temperature, salinity and pH on the common shore shrimp, Palaemonetes vulgaris; the freshwater flea, Daphnia pulex and the scud, Gammarus pseudolimnaeus. The compounds to be investigated include representatives of two major classes of insecticides: the organosphosphate malathion, and the carbamate aldicarb, as well as the triazine herbicide atrazine. Short term bioessays will be conducted to determine the minimal concentration for each substance that will affect the reproduction, morphology and respiration of the organisms. Although short term effects will be documented, the primary interest of the investigation is to study the long-term effect on the organisms resulting from continuous exposure to low-level concentrations of pesticides in combination with other factors.
