Concern over the effects of chemicals in the environment has been increasing for many years. Environmental contamination by DDT, Aldrin, Dieldrin, mercury, PCBs, organotins and many other sub stances are all part of the public consciousness and have led to widespread attention to this topic. Some of the concerns have arisen because human health has been affected when contaminants have been consumed via the food chain-for instance in the case of 'Minimata disease' in Japan. In other cases, direct effects on other components of ecosystems have given cause for alarm. The toxic effects which any...

Concern over the effects of chemicals in the environment has been increasing for many years. Environmental contamination by DDT, Aldrin, Dieldrin, mercury, PCBs, organotins and many other sub stances are all part of the public consciousness and have led to widespread attention to this topic. Some of the concerns have arisen because human health has been affected when contaminants have been consumed via the food chain-for instance in the case of 'Minimata disease' in Japan. In other cases, direct effects on other components of ecosystems have given cause for alarm. The toxic effects which any...