The Tennessee Department of Environment and Conservation (TDEC) today announced a precautionary fish consumption advisory for bass species in a portion of the East Fork Stones River in Rutherford County.
"Because eating fish with elevated levels of mercury is a risk Tennesseans can avoid, we provide this information so that the fishing community can make informed choices about whether or not to consume the fish they catch," said Jennifer Dodd, director of the Division of Water Resources for TDEC.
The advisory is the result of fish tissue sampling at multiple stations in the summer and fall of 2018, which indicated that in species such as smallmouth bass and largemouth bass, mercury trigger points recommended by both the Environmental Protection Agency (EPA) and Food and Drug Administration are being exceeded.
It's advised that pregnant or nursing mothers and children avoid eating bass species from the portion of the East Fork included in the advisory. All others should limit consumption of bass to one meal per month. Other recreational activities on the East Fork Stones River such as boating, swimming, wading, and catch-and-release fishing carry no risk from mercury.
The advisory extends from the mouth at the confluence with the West Fork Stones River in upper J. Percy Priest Reservoir upstream to Betty Ford Road near Lascassas. Walter Hill Lake, a small impoundment on the East Fork near the community of Walter Hill, is included in the advisory.
During the 2018 survey, fish were collected from four locations on the East Fork Stones River. Walter Hill Lake was sampled in August, October and December. Stations near Jefferson Pike (mile 8.0) and Betty Ford Road (mile 15.4) were sampled in October. The river near Mona Boat Ramp (mile 4.3) was sampled in December.
TDEC is not aware of any local sources of mercury to the East Fork Stones River. According to the EPA, atmospheric deposition due to the global burning of coal is the most frequent reason for elevated levels of mercury in fish.
TDEC will post warning signs at public access points and will work with the Tennessee Wildlife Resources Agency and the U.S. Army Corps of Engineers to communicate this information to the public.
About Fish Consumption Advisories
The Tennessee Water Quality Control Act identifies the commissioner of the Department of Environment and Conservation as having the authority and responsibility to issue advisories for either water contact hazards like pathogens or excessive health risks due to the accumulation of contaminants in fish or shellfish. Tennessee's General Water Quality Criteria provide additional guidance regarding the conditions under which advisories may be warranted.
There are two types of fish consumption advisories issued by TDEC based on the levels of contaminants present in fish tissue. "Do not consume" fishing advisories are issued when levels of contaminants in fish tissue would represent a threat to the general population. Precautionary advisories are issued when contaminant levels are lower, but would still pose a risk to sensitive subpopulations such as children, pregnant women, nursing mothers and those who frequently eat fish from the same body of water.
According to the EPA, mercury is a naturally occurring element that can be found throughout the environment. Human activities such as burning coal, some industrial processes and waste incineration have caused the amount of mercury in some areas to increase. The primary way people in the U.S. are exposed to mercury is by eating fish containing methylmercury, a toxic form of mercury that accumulates easily in organisms.
Where new advisories have been issued, TDEC will immediately begin the process of putting up signs at primary public access points. TDEC works in partnership with the Tennessee Wildlife Resources Agency to communicate information about fishing advisories.