Do fish consumption advisories for mercury adequately protect the public?

Abstract

Mercury (Hg) is a toxic metal found at elevated concentrations throughout the world. Humans are exposed by consuming contaminated fish. State agencies warn the public to limit fish consumption from specific waterbodies when elevated Hg is detected (site-specific advisory). Some states issue warnings, advising limited consumption from any state waters since fish may contain high Hg (statewide advisory). I evaluated the accuracy of these advisory systems using estimated Hg concentrations in intermediate sizes of four freshwater gamefish at 866 waterbodies. Waterbodies where Hg concentrations exceeded 300 ng/g, the Environmental Protection Agency's screening value for hazardous fish, were assumed to need advisories. Comparing predicted advisories to state-issued advisories revealed most waterbodies expected to have site-specific advisories lack them. Applying statewide advisories results in warnings on waterbodies with fish below EPA advisory levels. I conclude the advisory systems fail to accurately reflect risk from fish with potentially hazardous levels of Hg