ECOTOXICOLOGY

The field of environmental toxicology, particularly as related to the area of ecotoxicology, continues to be a rapidly developing discipline of environmental science (Connell and Miller, 1984; Duffus 1980; Guthie and Perry, 1980; Hoffman et al., 1995; Moriarity 1988; Truhaut, 1977). The term ecotoxicology was introduced by Truhaut in 1969 (Truhaut, 1977) and this field is a natural extension of toxicology. It is best defined as the study of the fate and effects of toxic substances on an ecosystem and is based on scientific research employing both field and laboratory methods (Kendall, 1982; Kendall, 1992; and Hoffman et al., 1995). Environmental toxicology as it is related to ecotoxicology requires an understanding of ecologic principles and theory as well as a grasp of how chemicals can affect individuals, populations, communities, and ecosystems (Kendall and Lacher, 1994; Hoffman et al., 1995). Measurements of biological impact are accomplished using either species-specific responses to toxicants (Smith, 1987) or impacts on higher levels of organization from individuals to populations, and so on. Ecotoxicology builds on the science of toxicology and the principles of toxicologic testing, though its emphasis is more at the population, community, and ecosystem levels (Moriarty, 1988). The ability to measure chemical transport and fate and exposure of organisms in ecotoxicologic testing is critical to the ultimate development of an ecologic risk assessment (U.S. EPA, 1992 a, b, c; Suter, 1993; Maughan, 1993)