April 1, 2015 – By studying fish and invertebrates in a creek with known mercury contamination, researchers are gaining a better understanding of the relationship between the toxin in the stream and bioaccumulation in organisms. While mercury concentrations in East Fork Poplar Creek in Oak Ridge, Tenn., have decreased significantly over the last 30 years, levels in tissue from fish have remained the same or increased. To understand why, a team led by Monica Poteat of Oak Ridge National Laboratory is examining the intricacies of the food chain and the biodiversity of the stream at locations about 10 kilometers apart. “Downstream sites have more complex community structures, which can lead to greater transfer of mercury to fish through the food chain,” said Poteat, who presented this work at the Carolinas Society of Environmental Toxicology and Chemistry Annual Meeting.
Oak Ridge National Laboratory