Metals in the Human Environment Strategic Network (MITHE-SN): the interface of risk assessment, public policy, and advocacy.

A 5-year strategic research network with a diverse base of industry, government, and academic partners was approved for support by National Sciences and Engineering Research Council of Canada (NSERC) on January 3, 2005. This Metals in the Human Environment Strategic Network (MITHE-SN) builds on, and further extends, science knowledge developed by the NSERC-sponsored Metals in the Environment Research Network (MITE-RN, 1999-2004). In addition to the initial award, the MITHE-SN received an additional 2-year grant specifically targeted to (1) enhance training opportunities for internships with international organizations, (2) increase international networking and linkages, and (3) optimize knowledge dissemination and technology transfer. The research program is comprised of three themes and represents a cascade of effects along food webs, from the lowest trophic levels to the highest consumers. Each of the themes addresses issues related to distinguishing the magnitudes and roles of natural background and anthropogenic metal inputs in biotic exposure to metals; estimating the bioavailable fraction of metals in the exposure media, thus better quantifying the true exposure concentration; and determining the factors that influence bioavailability of metals in media, so that predictive models can be developed for use in the development of site-specific metals criteria.