Ranking of toxics release inventory chemicals using a Level III fugacity model and toxicity

In an effort to lessen the environmental impact of chemicals discharged by industry, some countries rank chemicals according to mass released each yea r and then set environmental protection policy based upon this ranking. The se rankings have driven industries and companies to change their process co nfigurations and their chemical releases to reduce the release of higher ra nking chemicals. Bur, chemicals that are higher ranked due to mass release may not be particularly toxic nor persistent in the environment; conversely , lower ranked chemicals may be substantially more toxic and persistent in the environment. The physical/chemical properties of forty five organic chemicals from the E PA's Toxic Release Inventory were used as inputs to a Level III fugacity mo del to estimate fate, transport, and steady state concentrations of chemica ls in the environment. The resulting concentrations in the air and water, f or each chemical, were determined using the fugacity model and were then co mpared with toxicity data, the ratio was used as an indication of the envir onmental impact of the release of each chemical. The chemicals were then ra nked according to the degree of environmental impact and the results were c ompared to other ranking systems reported in the literature. (C) 1999 Publi shed by Elsevier Science Ltd on behalf of the IAWQ. All rights reserved.