Selection of bioaccumulation criteria for environmental emergency (E2) planning

Environment Canada's Environmental Emergency regulations require the evaluation of a substance by a Risk Evaluation Framework (REF). Bioaccumulation criteria are used within the environmental hazard ratings section of the REF to determine the risk of a substance to organisms and are obtained from 3 types of measurements depending on data reliability: (1) bioaccumulation factors (BAF); (2) bioconcentration factors (BCF); and (3) an octanol-water partition coefficient (log Kow). This paper presented details of a study of international and regional bioaccumulation criteria conducted to aid in determining appropriate criteria for E2 regulations and plans, with specific reference to substances toxic to aquatic organisms. An E2 plan is required if a substance has a bioconcentration factor of more than 500 in conjunction with aquatic toxicity. Bioaccumulation criteria from several sources for 745 substances were obtained to aid in choosing the most important parameters. Various international and regional criteria were examined and corresponding sources were summarized, and different source criteria was compared with empirical chemical data. The criteria chosen included both log Kow values and BCF values, although it was suggested that BCF and BAF are more realistic measures of bioaccumulation than log Kow, as they are derived from animal studies. The chosen values agreed with the virtual elimination criteria set out by the Canadian Environmental Protection Act (CEPA) 1999 as well as United States Environmental Protection Agency (EPA) criteria. It was concluded that the bioaccumulation criteria for E2 planning will help Environment Canada ensure the protection of the environment from hazardous substances. 11 refs., 3 tabs., 5 figs