Comprises most of the presentations given at the Fourth International Workshop on Quantitative Structure-Activity Relationships (QSAR) in Environmental Toxicology, September 1990. Topics addressed include statistical techniques and estimation of physico-chemical properties, environmental fate processes, toxicokinetic behavior, environmental toxicity and mechanism of action, and the application of QSAR in various fields. The workshop was intended to stimulate interchange between people working in the fields of drug design and the environmental sciences; the underlying processes that lead to the beneficial effects of drugs are the same as those that cause the adverse effects of environmental pollutants. Annotation copyright Book News, Inc. Portland, Or.