PARENT SESSION
MP7 - Integration of Risk Assessment & Economics in Risk Management
Chair: Toll, John1, 1 Parametrix, Inc., Kirkland, WA
Co-chair: DeForest, David2, 2 Parametrix, Inc., Bothell, WA
2:10 PM to 5:30 PM - Monday, 18 November 2002
Room Ballroom A
(302) An Index Of The Ecological Impacts Of Water Toxics Emitted To Freshwater Ecosystems.
Papasavva, Stella*,1, Beltramo, Mark1, Cadle, Steven1, 1 General Motors Corp., Warren, MI, USA
ABSTRACT- The goal of this study is to assess the economic and ecological impacts of water toxics emitted to freshwater ecosystems. We have developed a composite Aquatic Toxicity Index (ATI) developed for freshwater for chronic toxicity conditions. The ATI expresses the physical impact of the chemicals to the ecosystem and it provides a ranking system that scales the potency of each chemical with respect to nickel. Nickel was chosen as the numeraire chemical because it's ATI value is in the midrange of values of the other chemicals. Monetary damage figures are provided in the literature for a handful of chemicals included in this study based on results obtained by Contingent Valuation Methods (CVMs). CVMs rely on surveys in which individuals are asked how they would evaluate the impact of an environmental problem. Using such values, we estimated the economic and ecological benefits associated with the elimination of one kilogram of nickel-equivalent emissions of each pollutant addressed in this study. The economic and ecological costs of the individual chemicals fall in the range of $10+4 - $10-8 per kilogram emitted to water, with the highest per-kilogram costs associated with dioxins and PCBs. We also compared the ATI index with measures of Aquatic Eco-Toxicity Potential (AETP) provided by the developers of the Life Cycle Analysis software GaBi and obtained using the European-based impact assessment tool EUSES 1.0, which was based on a more elaborate fate and transport model. The correlation between log(ATI) and log(AETP) is greater than 0.8. Therefore, we believe that our inexpensive approach in terms of computational resources and mathematical modeling may provide a reasonable approach to approximating complex environmental impact assessment for chronic aquatic emissions.
Key words: Aquatic Toxicity Index, Ecological Impact of Water Pollutants, Economic Impact of Water Pollutants, Life Cycle Impact Assessment