Emerging Opportunities in Management of Selenium Contamination

Abstract

The metalloid selenium (Se) has the diverse reactivity characteristic of the chalcogens in addition to organometallic behavior. Laboratory measurements indicate that Se is an acute reproductive toxicant, which makes it a concern for the environment. Yet to date, a lack of understanding on how Se species distribute through food websbioaccumulation not seeming to conform to dissolved concentrationshas made for very heterogeneous regulation across jurisdictions. In this Feature, Luoma and Presser review Se’s idiosyncrasies to provide an outlook for more realistic ecotoxicologically based regulation.

Status of selenium in south San Francisco Bay—A basis for modeling potential guidelines to meet National tissue criteria for fish and a proposed wildlife criterion for birds

“…The long residence time, high nutrient inputs, and deposition of fine-grained sediments allow some degree of oxygen-depletion in the sediments, especially in the sub-surface (Crauder and others, 2016). This could also affect Se transformation (Luoma and Presser, 2009) and speciation on suspended particulate material and in sediments (Meseck and Cutter, 2012). Because these processes vary in intensity and length from year to year, seasonal cycles in Se concentrations and bioavailability are expected to be complex.…”

“…Composition of food webs and the inherent tendency of different organisms in the food web to accumulate Se are important (Luoma and Presser, 2009). Selenium bioaccumulation in individuals also can vary if environmental conditions affect feeding rates or food composition affects assimilation efficiencies (Luoma and Rainbow, 2005).…”

“…Site-specific processes both in ecosystems and the estuary itself that affect the fate of Se also will be considered. This assessment will allow us to determine whether it is feasible to use the Presser-Luoma Ecosystem-Scale Selenium Model (Luoma and Rainbow, 2005;Luoma and Presser, 2009;Presser and Luoma, 2010a) in South Bay and if so, how. In employing the model, the goals are to address the questions:…”

Levels of arsenic, mercury and selenium inClarias gariepinusfrom Sagua la Grande River, Cuba

“…In aquatic environments these elements have complex biochemical cycles that include the formation of organic species. Furthermore, Se and Hg tend to increase all along the trophic chain (Donohue and Abernathy, 1999;Clarkson and Mago, 2006;Luoma and Presse, 2009).…”

“…However, above the relatively low normal physiological requirements, it can be toxic (Letavayova´et al, 2006). In aquatic systems, Se is accumulated through food chains, resulting in the exposure of animals, such as fish and birds, from higher trophic levels causing them problems in their reproductive systems which adversely affect populations (Lemmy, 1993(Lemmy, , 1996Luoma and Presse, 2009). …”