Bioaccumulation of methylmercury in wood frogs and spotted salamanders in Vermont vernal pools.

ABSTRACT: Mercury (Hg) has accumulated in forested landscapes in the Northeastern U.S., and hotspots with enhanced deposition have been identified throughout the region. Due to a variety of favorable landscape characteristics, including relatively high dissolved organic carbon (DOC), fluctuating water levels, and low pH and dissolved oxygen, vernal pools provide ideal conditions for the conversion of Hg to its more toxic and bioavailable form, methylmercury (MeHg). Yet little is known about the concentrations, speciation, and bioavailability of Hg in vernal pools, or its bioaccumulation in vernal pool fauna and potential export into terrestrial systems. We investigated the role of forest cover type on the bioaccumulation of MeHg in wood frog (Lithobates sylvatica) and spotted salamander (Ambystoma maculatum) eggs, larvae, and adults, and investigated relationships among MeHg and water chemistry (pH, DOC). Water samples from pools located in coniferous stands had greater concentrations of THg and MeHg compared to deciduous pool water, and showed significant positive correlation to DOC (r?=?0.683, P?

SUBMITTER: Faccio SD 

PROVIDER: S-EPMC6732234 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature