Ecotoxicology is alleged to be the integration of toxicology and ecology or, as Chapman (2002) suggested, “ecology in the presence of toxicants”. It aims to predict the effects upon natural populations, communities, or ecosystems - ‘the ecosystem’- of stressors, be they anthropogenic in origin or otherwise. It differs from Environmental Toxicology in that it integrates the effects of stressors across all levels of biological organisation from the molecular to whole communities and ecosystems, whereas environmental toxicology focuses upon effects upon the individual (Maltby & Naylor, 1990).
The publication in 1962 of Rachel Carson's seminal volume, Silent Spring catalysed the separation of environmental toxicology - and, subsequently, ecotoxicology - from classical toxicology. The revolutionary element in Carson's work was her extrapolation from single-organism effects to effects at the whole ecosystem and the "balance of nature" (Bazerman et al, 2006). This systemic study is distinct from the anthropocentric nature of classical toxicology and ecotoxicology is, therefore, a far broader discipline incorporating aspects of ecology, toxicology, physiology, molecular biology, analytical chemistry and a wealth of other disciplines to study the effects of xenobiotics in an ecosystem. The ultimate goal of this approach is to be able to predict the effects of pollution so that, should a pollution incident occur, the most efficient and effective action to remediate the detrimental effects can be identified. In those ecosystems that are already impacted by pollution ecotoxicological studies can inform as to the best course of action to restore ecosystem services and functions efficiently and effectively.