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

(MAC-1117-641422) Can the unit world approach provide a common and consistent framework for assessing metals and organics?

Mackay, D.¹, Webster, E.¹, Harvey, C.¹, Doyle, P.², ¹ Trent University, Peterborough, Ontario, Canada² Environment Canada, Gatineau, Quebec, Canada

ABSTRACT- There is an obvious incentive to establish a common "playing field" for assessing the toxicity, fate and exposure potential of all chemicals of commerce, including metals and organics. A number of chemical groups are identified and their environmental properties, similarities and differences are discussed, especially with relation to their partitioning, bioavailability, bioaccumulation and degradation. It is suggested that the environmental toxicity, fate and exposure of all chemicals can be evaluated and compared, at least for the purposes of relative ranking, using unit world models based on the fugacity or aquivalence equilibrium criteria. Examples are given of such assessments for a variety of chemicals including organics and metals and the results are discussed. It is concluded that a common, consistent assessment framework can be developed.

Key words: chemical assessment, metals, mass balance, unit world model