ABSTRACT
Toxicology is concerned with defining the potential of a substance to produce adverse effects. Environmental toxicology is the study of health effects of low level, often long-term, exposure of biological systems and, in particular, of human populations, to environmental toxins or poisons. It is a multidisciplinary subject that draws together a number of medical and scientific disciplines. Environmental toxicology is a major component of public health research. Hazard evaluation determines whether any of the known potential adverse effects will develop under specific conditions of use. Toxicology is thus only one aspect taken into account in hazard evaluation. There are multiple circumstances where one has to assess the risk of otherwise safe chemicals or of the processes leading to their production.
