This discussion is the third in a series of four recordings addressing aspects of the forest products industry’s early involvement with the dioxin issue. The series focuses upon the finding of trace amounts of chlorinated dioxins and furans in pulp mill effluent and other non-atmospheric emission vectors in the late 1980s, and is intended to document via interview recollection the industry’s successful efforts to reduce or eliminate these substances from its effluents and products, and NCASI’s involvement with those efforts. This discussion addresses studies by NCASI to determine bioaccumulation factors for TCDD and TCDF in fish.