Influence of methylmercury from tributary streams on mercury levels in Savannah River Asiatic clams
M.H. Pallera, C.H. Jagoeb, H. Bennettc,
H.A. Brantb, J.A. Bowersa
aEnvironmental Analysis Section, Westinghouse
Savannah River Company, Building 773-42A, Savannah River Site, Aiken,
SC 29808, USA
bSavannah River Ecology Laboratory, University of Georgia,
Drawer E, Aiken, SC 29802, USA
cDepartment of Biology, University of South Carolina at Aiken,
Aiken, SC 29803, USA
Received 10 July 2003; accepted 10 November 2003
Abstract
Average methylmercury levels in five Savannah River tributary streams,
sampled 11 times over 2 years (0.170 ng/ 1), were nearly twice as high
as in the Savannah River (0.085 ng/1l). Total mercury levels in the tributaries
(2.98 ng/ 1) did not differ significantly from the river (2.59 ng/l).
All of the tributaries drained extensive wetlands that would be expected
to support comparatively high rates of methylation. Mercury concentrations
in Asiatic clams (Corbicula fluminea) collected from the discharge
plumes of Savannah River tributaries (average of 0.044 µg/g wet
weight) were significantly (P<0.001l) higher than in Asiatic clams
collected from the Savannah River upstream from the tributary mouths (average
of 0.017 µg/g wet weight). These results indicate that streams draining
wetlands into coastal plain rivers can create localized areas of elevated
methylmercury with resulting increases in the mercury levels of river
biota.
@ 2003 Elsevier B. v: All rights reserved.
SREL Reprint #2799
Paller, M. H., C. H. Jagoe, H. Bennett, H. A. Brant and J. A. Bowers. 2004. Influence of methylmercury from tributary streams on mercury levels in Savannah River Asiatic clams. Science of the Total Environment 325:209-219.
