Methodology used for a laboratory determination of relative contributions of water, sediment and food chain routes of uptake for 2,3,7,8-TCDD bio-accumulation by lake trout in lake Ontario

To investigate the relative importance of water, sediment, and food as a source of 2,3,7,8-tetrachlorodibenzodioxin (TCDD) in fish, long-term experiments were carried out with lake trout (Salvelinus namaycush). An illustrated description of the experimental equipment is included, and procedures used to prepare the sediment and the food, dose the sediment, and feed the fish are described. The food chain was the principle route for accumulation of TCDD in fish, and contact with contaminated sediment was of secondary importance. There was no significant uptake from the water.