SREL Reprint #3242

DNA double-strand breakage as an endpoint to examine metal and radionuclide exposure effects to water snakes on a nuclear industrial site

Stephanie M. Murray1,2, Karen F. Gaines2,3, James M. Novak3, Michael Gochfeld2,4, and Joanna Burger1,2

1Division of Life Sciences, Rutgers University, Piscataway, NJ, USA
2Consortium for Risk Evaluation with Stakeholder Participation, Environmental and Occupational
Health Sciences Institute, Piscataway, NJ, USA
3Department of Biological Sciences, Eastern Illinois University, Charleston, IL, USA
4Environmental and Community Medicine, UMDNJ-Robert Wood Johnson Medical School,
Piscataway, NJ, USA

Abstract: This study examined metal levels (especially U and Ni) in the tail tissues of water snakes from contaminated (Tim’s Branch) and reference areas on the Department of Energy’s Savannah River Site (SRS). Home ranges of snakes were quantified to determine the ratio of the habitat that they use in relation to the contaminated areas to better estimate exposure Compared to conventional methods that do not. The exposure assessment indicated that water snakes in the contaminated areas could expect U exposure at 3–4 orders of magnitude greater than the Agency for Toxic Substances and Disease Registry’s Minimum Risk Level (MRL) from ingestion of amphibians and fish. Ni and U, in addition to Se, Mn, and Cu, were related to increased DNA double-strand breakage (DDSB) in water snakes.We report burdens for each metal individually, but the results of the DDSB indicated that these metals did not behave independently, but as a suite. If we did not have a secondary endpoint (DDSB), we might have assumed from the exposure predictions and tissue burden analyses that U was the sole metal of concern to water snakes in Tim’s Branch. These data also imply that these toxicants do not biomagnify at the spatial and temporal scale of this study.

Keywords: DNA double-strand breaks, exposure, uranium, Nerodia, nickel, water snakes

SREL Reprint #3242

Murray, S. M., K. F. Gaines, J. M. Novak, M. Gochfeld, and J. Burger. 2010. DNA double-strand breakage as an endpoint to examine metal and radionuclide exposure effects to water snakes on a nuclear industrial site. Human and Ecological Risk Assessment 16(2): 282-300.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).