According to that quoted in http://www.bio.hw.ac.uk/edintox/enviro.htm (a cool site): Environmental toxicology and ecotoxicology are terms used to describe the scientific study of the adverse effects on living organisms that chemicals can have when released into the natural environment. There is a tendency to apply the term "environmental toxicology" only to the study of direct effects of environmental chemicals on human beings and the term "ecotoxicology" only to the study of the effects of chemicals on ecosystems and their nonhuman components.
Note the following excerpt from the category description: Environmental toxicology and ecotoxicology are terms used to describe the scientific study of the adverse effects on living organisms that chemicals can have when released into the natural environment.
Information about Congress, Meetings and Workshops in Ecotoxicology and related fields
Radioecology is a scientific discipline that studies all aspects of the environmental impact of radioactive substances, from human radioprotection to ecological risk assessment, in relation to natural and man made pollution and waste