ABSTRACT
The pollution hazard has a different significance when it is applied to human health rather than to the survival of other organisms. The pollution hazard for man is evaluated on the actual (or potential) damage produced at the individual and population levels. For other organisms the hazard is exclusively evaluated at the population and community levels. Consequently, environmental pollution is considered noxious only if the population viability is reduced. Therefore, the final aim of studies on ecosystem pollution is to obtain knowledge of the effects on populations and communities. It is evident that protecting populations also protects resources such as air, soil, and water. Research on the concentration and distribution in the environment of pollutants, their associated metabolites, and their physicochemical forms is very interesting. On the other hand, the results from these studies may be utilized for the protection of the environment only if they are finalized to the knowledge of the actual (or potential) effects on the community. From this point of view, a close connection between research on pollutants and that on their biological effects seems to be necessary to establish relationships between the pollution level and the consequent damage to the biota. In several cases there is, unfortunately, no collaboration between chemist and biologist, and the research of the latter is often limited to laboratory experiments and the description of communities living in polluted environments.
