SREL Reprint #3727

Bioaccumulation of contaminants in Scarabaeidae and Silphidae beetles at sites polluted by coal combustion residuals and radiocesium

Ansley E. Silva1, Robert J. Speakman2, Brittany F. Barnes1, David R. Coyle1,3, James C. Leaphart1,4,
Erin F. Abernethy4,5, Kelsey L. Turner1,4, Olin E. Rhodes Jr.4,5, James C. Beasley1,4,
and Kamal J.K. Gandhi1

1D.B. Warnell School of Forestry and Natural Resources, University of Georgia,
180 E Green Street, Athens 30602, GA, USA
2Center for Applied Isotopes Studies, University of Georgia, 120 River Bend Road, Athens 30602, GA, USA
3Department of Forestry and Environmental Conservation, Clemson University,
121 Lehotsky Hall, Clemson 29634, SC, USA
4Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken 29802, SC, USA
5Odum School of Ecology, University of Georgia, 140 E. Green Street, Athens 30602, GA, USA

Abstract: Anthropogenic contamination from coal-fired power plants and nuclear reactors is a pervasive issue impacting ecosystems across the globe. As a result, it is critical that studies continue to assess the accumulation and effects of trace elements and radionuclides in a diversity of biota. In particular, bioindicator species are a powerful tool for risk assessment of chemically contaminated habitats. Using inductively coupled plasma mass spectrometry (ICP-MS) and auto-gamma counting, we analyzed trace element and radiocesium contaminant concentrations in Scarabaeidae and Silphidae beetles (Order: Coleoptera), important taxa in decomposition and nutrient cycling, at contaminated and reference sites on the Savannah River Site, South Carolina, U.S. Our results revealed variability in trace element concentrations between Scarabaeidae and Silphidae beetles at uncontaminated and contaminated sites. Compared to Scarabaeidae, Silphidae had higher levels of chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn). Unexpectedly, concentrations of Cr, Cu, and Ni were higher in both taxa at the uncontaminated sites. Scarabaeidae and Silphidae beetles at the coal combustion waste site consistently had high concentrations of arsenic (As), and Scarabaeidae had high concentrations of selenium (Se). Of the 50 beetles analyzed for radiocesium levels, two had elevated radioactivity concentrations, both of which were from a site contaminated with radionuclides. Our results suggest carrion beetles may be particularly sensitive to bioaccumulation of contaminants due to their trophic position and role in decomposition, and thus are useful sentinels of trace element and radionuclide contamination.

Keywords: Inductively coupled plasma mass spectroscopy; Radiocesium; Radioecology; Savannah River Site; Scavenger beetles; Trace elements

SREL Reprint #3727

Silva, A. E., R. J. Speakman, B. F. Barnes, D. R. Coyle, J. C. Leaphart, E. F. Abernethy, K. L. Turner, O. E. Rhodes Jr., J. C. Beasley, and Kamal J. K. Gandhi. 2023. Bioaccumulation of contaminants in Scarabaeidae and Silphidae beetles at sites polluted by coal combustion residuals and radiocesium. Science of the Total Environment 904: 166821.

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