Risks from mercury in anadromous fish collected from Penobscot River, Maine

Levels of total mercury were measured in tissue of six species of migratory fish (alewife, American shad, blueback herring, rainbow smelt, striped bass, and sea lamprey), and in roe of American shad for two consecutive years collected from the Penobscot River or its estuary. The resultant mercury levels were compared to reference doses as established in the U.S. Environmental Protection Agency (EPA) Integrated Risk Information System and wildlife values. Mercury concentrations ranged from 4 mu g/kg ww in roe to 1040 mu g/kg ww in sea lamprey. Sea lamprey contained the highest amounts of mercury for both seasons of sampling. Current health advisories are set at sufficient levels to protect fishers from harmful consumption of the fish for mercury alone, except for sea lamprey. Based upon published wildlife values for mink, otter, and eagle, consumption of rainbow smelt, striped bass, or sea lamprey poses a risk to mink; striped bass and sea lamprey to otter; and sea lamprey to eagle. For future consideration, the resultant data may serve as a reference point for both human health and wildlife risk assessments for the consumption of anad-romous fish. U.S. EPA works with federally recognized Tribes across the nation greatly impacted by restric-tions on sustenance fishing, to develop culturally sensitive risk assessments. Published by Elsevier B.V.

Automated summary

The study measured mercury levels in tissues of various migratory fish species, with sea lamprey showing the highest mercury content. This poses potential risks to both human health and wildlife, serving as a reference point for future assessments.