A multiyear survey of mercury in Artemia biomass and cysts collected from the Great Salt Lake, UT.
Investigations of contaminants in the anoxic benthic zone of the GSL have shown elevated mercury (Hg) levels. However, such excess concentrations of Hg are largely confined to the benthic zone of the GSL. Other scientific studies of the upper, biologically relevant, layers of the open water of the GSL have not found such elevated levels of Hg in the water or in the biota. We conducted a two-fold investigation of Hg in Artemia: 1) Hg in cysts at each step of the harvesting and industrial processes, and; 2) Hg in archived Artemia cysts and cysts collected from the photic zone of the GSL. Our analyses of cysts from the industrial pathway showed values near or below the limits of detection. Our temporal study of cysts does not show a trend of increasing Hg levels over multiple years. Hg values in cysts taken from the open water of the GSL are well below the EPA dietary standard for meHg (0.3 mg/kg ww) and are also below the European Union Directive on heavy metals in aquaculture feed (0.5 mg/kg dw).