AN EVALUATION OF MER-SPECIFIED REDUCTION OF IONIC MERCURY AS A REMEDIAL TOOL OF A MERCURY-CONTAMINATED FRESH-WATER POND

The potential for mer-mediated reduction/volatilization of ionic mercu ry as a tool in the decontamination of a freshwater pond was evaluated using laboratory incubations and a microcosm simulation. In flask ass ays inoculations with ionic mercury-resistant bacteria (10(5)-10(7) ce lls ml(-1)) isolated from the pond, significantly increased the rate o f mercury loss (MANOVA, P less than or equal to 0.05) relative to unin oculated controls. The effects of cell density, mercuric mercury conce ntration, addition of nutrients and supplementation with the sulfhydry l reagent beta-mercaptoethanol on the rate of mercury loss, were inves tigated. Inoculation (by 10(5) cells ml(-1)) of a flow-through microco sm that simulated the cycling of mercury in the contaminated pond, sti mulated by more than 4-fold the formation of volatile elemental mercur y. Thus, biological formation of volatile mercury may hold a promise a s a remedial tool of contaminated natural waters.