ARE MERCURY METHYLATION AND SELENATE REDUCTION INDEPENDENT PROCESSES IN AQUATIC ECOSYSTEMS?
Both mercury (Hg) and selenium (Se) can bioaccumulate within aquatic ecosystems and are toxic to organisms when found at high concentrations. Individually, high concentrations of either Hg or Se in water result in harmful impacts to biota, but the presence of both trace metals has been shown to have antagonistic effects; in fact, the assimilation efficiency of Hg is decreased when Se is present. Due to this relationship, many studies suggest that increased environmental concentrations and consumption of Se is a pathway to reduce Hg toxicity in organisms. Yet, despite this important link, little is understood in regard to biogeochemical factors promoting the environmental conversion of Hg and Se into more bioavailable forms and thereby leading to the concurrent uptake of Hg and Se by biota. We present a literature synthesis of the biogeochemical interaction between mercury and selenium, as well as abiotic factors that impact their bioavailability. We examine mechanisms for environmental interaction of Hg and Se and evidence for an antagonistic effect of Se on Hg toxicity.
Jacqueline Gerson (Primary Presenter/Author), Duke University, email@example.com;
Emily Bernhardt ( Co-Presenter/Co-Author), Duke University, firstname.lastname@example.org;