Ecotoxicological Effects

Ecotoxicology is the study of the three S’s. It is the study of the toxic effects of substances on nonhuman species in complex systems (Figure 6.1). Ecotoxicological effects are changes in the state or dynamics of an organism, or at other levels of biological organization, resulting from exposure to a chemical. These levels may include the subcellular level, the cellular level, tissues, individuals, populations, communities and ecosystems, and finally, landscapes. The number and variety of interactions, increase dramatically in this order, i.e. with the complexity of the systems. Due to the complexity of these systems, models are needed to describe the interactions between substances and species (toxicology), between substances and systems (chemistry) and between species in systems (ecology), as well as to account for the overall integration of these interactions. These models may require input from mathematics, statistics and informatics. In order to define ecotoxicology, three questions need to be asked: 1.Are the disciplines working on the same questions and subjects?2.What knowledge and techniques are needed?3.Do interactions occur?