State Agencies release fish consumption guidelines
Few things compare to a meal of fresh-caught fish from one of Pocahontas County's eight rivers or their tributaries, but state officials have released their latest health advisories for those who enjoy eating sport fish.
The updated guidelines released last week by the Department of Natural Resources and Department of Health and Human Resources give recommended consumption limits of fish caught in West Virginia's lakes and streams. The cause for concern are contaminants such as mercury, dioxins, PCBs and selenium, all of which can accumulate in the bodies of fish and the humans who eat them, leading to long-term health risks.
The general guidelines for fish caught in West Virginia are no more than one meal per month of white or hybrid striped bass; two meals a month of black bass, channel catfish greater than 17 inches, flathead catfish, rock bass, walleye, saugeye, sauger and all suckers; and one meal a week of channel catfish less than 17 inches and all other species. Rainbow trout are the only fish for which the state hasn't issued a recommended limit.
How much fish constitutes a "meal" depends on a person's weight. For a child of 51-70 pounds, three ounces is the recommended meal limit. For an adult of 131-150 pounds, the recommendation is seven ounces. A detailed chart is included in the DNR consumption advisory.
The primary contaminants responsible for the recommended limits are mercury and PCBs, according to the DNR's 2012 Statewide Consumption Advisories.
While low levels of mercury are naturally found in the earth's crust, additional, inorganic mercury is released into the air through the burning of fossil fuels, mining and industrial emissions, according to the DHHR. This mercury is able to travel long distances in the air before setting on soil and bodies of water.
In water, small organisms convert this inorganic mercury into an organic form, methyl mercury. Methyl mercury then enters the food chain by binding with the particles and sediment eaten by fish. Larger fish may prey on smaller, mercury-contaminated fish, resulting in stored amounts of mercury in many commonly caught sport fish. Because fish break down mercury at a very slow rate, it tends to accumulate in their tissues and organs.
In humans, mercury can likewise accumulate in the body and cause damage to the nervous system. The U.S. Environmental Protection Agency and the Food and Drug Administration have issued specific guidelines for pregnant women, women of childbearing age, nursing mothers and children concerning fish consumption of both wild-caught and store-bought fish.
The EPA and FDA recommend women of childbearing age and children limit their intake of fish-including store-bought fish and tuna- to two-to-three meals per week.
Polychlorinated biphenyls, or PCBs were once widely used as coolants and lubricants in transformers, capacitors and other electrical equipment. While the U.S. halted the use of PCBs in 1979, older pieces of equipment still contain them, and the chemicals have persisted in the environment.
In experiments with lab animals, PCBs have been found to cause liver damage, skin irritation and cancer, as well as causing reproductive and developmental harm.
In addition to the statewide consumption advisory, the DNR has issued specific guidelines for fish caught in the Bluestone River, Fish Creek, Flat Fork Creek, Kanawha River, Little Kanawha and Hughes Rivers, Upper Mud and Mount Storm lakes, Pinnacle Creek, R.D. Bailey Lake, the Shenandoah River, Summersville Lake and Sutton Lake.
In Pocahontas County, a specific consumption advisory of one meal per month also applies to smallmouth bass smaller than 12 inches caught in the Greenbrier River, due to mercury.
The Kanawha River is the only body of water with an advisory for dioxins, while the Upper Mud and Mount Storm lakes, as well as Pinnacle Creek are the state's only bodies listed with advisories for selenium.
Dioxins are a byproduct of human activities including incineration, chlorine bleaching of pulp and paper, some types of chemical manufacturing and processing and other industrial processes, according to the DHHR. In the Kanawha Valley, the DHHR has noted that past industrial activity near Nitro resulted in several dioxin-contaminated sites, particularly where industrial solvents and the herbicide 2,4,5-T were produced. Contamination was further spread by poor disposal practices that were common earlier in the 20th century, including burying drums, dumping of dioxin-contaminated liquid wastes and incineration of dioxin-contaminated materials, according to the DHHR.
Long-term exposure to dioxins is linked to impairment of the immune system, the developing nervous system, the endocrine system and reproductive functions, according to the World Health Organization. Chronic exposure of animals to dioxins has resulted in several types of cancer, the WHO states.
Selenium is used in the electronics and glass industries, but it can also be found in plastics, paints, enamels, inks, rubber and some anti-dandruff shampoos. The chemical is also used in the manufacture of pharmaceuticals and pesticides. Areas where coal fly-ash is disposed can also leach selenium into the surrounding soil, according to the DHHR.
While selenium is an essential nutrient, it is toxic to humans and animals at high concentrations, affecting the nervous system, skin, nails and hair, according to the EPA.
More information on the fish consumption advisories is available online at http://www.wvdhhr.org/fish/ or found in the 2012 Division of Natural Resources fishing regulations at http://www.wvdnr.gov/fishing/Regs12/regs_Consumption.pdf. A paper copy of the 2012 advisory may be obtained from the Office of Environmental Health Services by calling 304-558-2981.
Drew Tanner may be contacted at firstname.lastname@example.org.