Veterinary environmental toxicology is concerned with environmental pollution and its possible ill-effects on animals. The Department of Analytical Chemistry and Toxicology of the Central Veterinary Institute has become increasingly involved in industrial and environmental toxicological problems affecting domestic as well as free-living wild animals during the last five years. Its main duties lie not only in the field of diagnostic procedures but it also deals with other factors such as inquiries into the facts of poisoning, tracing poisons to their sources, modes of dissemination and contamination of the environment and food of animals with toxic substances. Some typical features and characteristics of research projects of the department, which are closely connected with these duties, are described. The results of investigations of special cases in the field and the experience thus gained clearly show the close relationship between veterinary and environmental toxicology.