TOXIC EMISSIONS INDEXES FOR GREEN DESIGN AND INVENTORY

The Toxics Release Inventory (TRI) is the most comprehensive and widel y reported information on hazardous discharges to the environment in t he United States. Unfortunately, the fledgling nature of the TRI may l ead to simplistic interpretations of the results. In particular, TRI s ummaries 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 toxi c than the least harmful. Thus, the simple rankings and time trends of facilities, industries, counties, and states as sources of toxic rele ases can be misleading because they have neglected relevant toxicologi cal data. We contrast the one-to-one ranking of the TRI data with a ra nking 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 stu dy is needed of uncertainties and limitations of this proposed approac h. Future applications may be found in green engineering design and ma nufacturing changes.