The toxicity of selenium
There is epidemiological and experimental evidence that Se can act as an antear cunogen and antimutagen at low levels but is capable of genotoxicity at higher concentrations(Bronzetti and della Croce, 1993). Several studies have also indicated an ameliorative effect of Se on Hg and cadmium toxicity in humans and aquatic animals. Additions of Se to Swedish lakes have been made in an attempt to accelerate the reduction of mercury concentrations in fish.