The main aims of the grant were: To separate in pure form and, where possible, identify the components of the evaporator foul condensate effluent of a selected kraft mill; to synthesize when necessary components of the waste to provide a sufficient sample for biological study; to determine the acute toxicity to fish of individual components of the evaporator condensate; to determine the acute toxicity to mammals of individual components of the evaporator; to provide appropriate groups within the National Institutes of Health samples of isolated and identified compounds for study of their chronic toxicity and carcinogenic activity in mammals; to evaluate more fully the relative importance of readily separable groups of toxic constituents of whole mill effluents deriving from different sources within the mills, with attention to their persistence and interactions.