PARENT SESSION
PS5 - TIEs & TREs
Sunday, 17 November 2002
8:00 AM to 6:30 PM
Exhibit Hall

(P069) Interactions between contaminants determine toxicity in stormwater runoff from an aluminum smelter.

Elphick, James^*,1, Bailey, Howard¹, ¹ EVS Environment Consultants, North Vancouver, BC, Canada

ABSTRACT- A toxicity identification evaluation (TIE) was performed on samples of stormwater runoff from an aluminum smelter which exhibited toxicity in larval development tests with the marine mussel Mytilus galloprovincialis. The observed pattern of toxicity was unusual because of a flat and sometimes inverted dose-response. The results of the TIE indicated that aluminum was responsible for toxicity, with the dose-response a function of the low solubility of aluminum and the interaction between aluminum, fluoride and pH. Supportive data included toxicity tests with aluminum at different pH values and concentrations of fluoride. Fluoride addition resulted in a large decrease in toxicity of aluminum; however, pH adjustment did not alter the toxicity of aluminum tested without fluoride. As part of the TIE, the cause of toxicity was also evaluated with the freshwater cladoceran, Ceriodaphnia dubia, and was also attributed to aluminum.

Key words: Toxicity Identification Evaluation, Stormwater, Mytilus galloprovincialis, Aluminum