Toxicant-induced mortality in models of daphnia populations

A method to determine the mortality effects of a hydrophobic chemical on a population is proposed. The ecotoxicological protocol is based on individual organism response and is derived from the static theory of “survival of the fattest.” This study, focusing upon effects of mortality and the effects of toxicant stress on population succession, examines the static assessment survival of the fattest in a dynamic population model. A premise in this approach is that risk assessment should not be based solely upon chemical properties of the toxicant and that the biology of the exposed organisms is an important factor in the determination of effects.