Toxic Emissions Indices for Green Design and Inventory

Date of Original Version







The Toxics Release Inventory (TRI) is the most comprehensive and widely reported information on hazardous discharges to the environment in the United States. Unfortunately, the fledgling nature of the TRI may lead to simplistic interpretations of the results. In particular, TRI summaries typically report total releases of toxic chemicals by weight, implicitly assuming that a discharge of substance A is equivalent to an equal weight discharge of substance B. In contrast, various indices of the toxicity to humans of the chemicals reported in the Inventory indicate that the most harmful are more than 1,000,000 times more toxic than the least harmful. Thus, the simple rankings and time trends of facilities, industries, counties, and states as sources of toxic releases can be misleading because they have neglected relevant toxicological data. We contrast the one-to-one ranking of the TRI data with a ranking based on relative toxicity, using "threshold limit value" (TLV) indices. The weighting scheme presented here is a useful first step for correcting the TRI but is certainly not definitive. Additional study is needed of uncertainties and limitations of this proposed approach. Future applications may be found in green engineering design and manufacturing changes.


Published In

Environ. Sci. Technol, 29, 2, 86A-90A.