ECOTOXICOLOGY
Ecotoxicology is the study of the toxic effects of chemicals on the aquatic and terrestrial environment. Ecotoxicologists study the immediate effect of a toxic substance on individual organisms and on species in food webs, with the ultimate aims of predicting effects on wildlife populations, ecosystems and on human food resources such as fish and shellfish.
Ecotoxocologists aim to understand (and ideally predict and prevent) undesirable events in the natural environment, by carrying out ecotoxicity testing and risk assessment on new chemicals that may be used, disposed, or otherwise reach the environment. They are often also involved in conducting detailed monitoring studies of invertebrates and fish in polluted rivers and estuaries, looking at species at many levels within a food chain. It may also be necessary to monitor the physiological and biochemical responses of organisms following exposure to a pollutant, which may reflect a toxic effect. In many cases, sub-lethal effects such as changes in behaviour, development or in reproduction may be just as important for the survival of a species as lethal effect.