W7 PM Metals in the Environment: Regulatory and Risk Concerns
Wednesday, 16 November 2005: 1:50 PM - 5:30 PM in 327-329

(CHA-1117-647457) Global geographic differences in marine metals toxicity.

Chapman, Peter¹, McDonald, Blair¹, Kickham, Peter¹, McKinnon, Sarah¹, ¹ Golder Associates, North Vancouver, BC, Canada

ABSTRACT- It has been hypothesized that toxicity to chemical contaminants may increase from polar to temperate to tropical species based on the pronounced temperature differences between these regions. Fully testing this hypothesis has required adequate polar (arctic and Antarctic) data, which have only recently become available, and only for four metals in marine environments: Cu, Cd, Zn, Pb. Data deficiencies in polar regions prohibit similar comparisons for other substances. This hypothesis was tested, focusing primarily on 96h LC50 values due to data availability constraints. Data were screened to ensure they were valid, representative of their specific geographic region, and that testing had been done under conditions representative of that region. Species sensitivity distributions (SSDs), HC5 and H50 values were determined together with their confidence limits. Despite claims by some authors to the contrary, substantive differences were found between the three geographic regions. Despite other claims and hypotheses, these differences were not predictable based on temperature. Finally, and again despite claims to the contrary, sensitivity data from one geographic region will not be universally protective of other regions.

Key words: metals, marine, acute toxicity, global