Metal (Cu, Ni, Fe, Co, Zn, Pb) and Ra-226 levels in meadow voles Microtus pennsylvanicus living on nickel and uranium mine tailings in Ontario, Canada: environmental and tissue levels

Abstract

Copper, nickel and iron levels were higher in samples of substrate, leachate and surface water of copper-nickel mine tailings than in those from uranium mine wastes or a control area, which were similar. Nickel and iron were also elevated in the vegetation from the copper-nickel workings. The gut of resident voles was contaminated by copper and nickel and the skin and hair by nickel and iron. Higher whole body burdens of copper and nickel were attributed to the higher levels in gut and skin. Higher levels of iron observed in bone and kidney tissue were the only indications of internal deposition of these metals. Cobalt, zinc and lead levels, when detectable, in leachate, vegetation and water differed little from, or were below, control levels in both tailings. Total body concentration of cobalt was lowest in animals from uranium mine tailings; their low skin contamination was due to low levels in the substrate. Total body burden of zinc did not differ among sites. No internal deposition of cobalt was seen. Although lead levels were higher in uranium mine tailings than elsewhere, no differences were seen in lead concentrations in vegetation or resident voles. Radium-226 was detected only in the samples and voles of uranium mine wastes; the voles carried the radium-226 in their gut, skin and skeleton.