A new study has raised concerns about California’s coastal fish supply, finding mercury and<"http://www.yourlawyer.com/topics/overview/PCBs_health_concerns"> polychlorinated biphenyls (PCBs) in several popular species of sports fish. The report, prepared by the State Water Resources Control Board’s Surface Water Ambient Monitoring Program (SWAMP), said the PCB and mercury contamination is widespread and a concern for human health.
This SWAMP report presents findings from 2009 – the first year of a two-year survey – including new data for 42 locations. Monitoring in 2009 centered on areas near Los Angeles and San Francisco, including San Francisco Bay.
Among other things, SWAMP found that Eight of 42 locations sampled had at least one fish species with an average methylmercury concentration that exceeded the Office of Environmental Health Hazard Assessment (OEHHA) threshold for considering a recommendation of no consumption for women of childbearing age and children. At all but one of the locations the highest concentrations were observed in sharks, which have a tendency to accumulate high levels of methylmercury worldwide.
Most of the other locations sampled had a moderate level of methylmercury contamination.
According to SWAMP, six of 42 locations sampled had at least one fish species with an average PCB concentration that exceeded the OEHHA threshold for considering a recommendation of no consumption, with San Francisco Bay and San Diego bay having “elevated concentrations.” Thirty-one of 42 locations had moderate contamination, while only seven located in the most remote areas had PCB concentrations lower than the lowest threshold, SWAMP said.
As we’ve reported previously, PCBs were used as coolants and lubricants in transformers, capacitors, and other electrical equipment and are suspected carcinogens; PCB Health Problems also include neurological effects. The toxic chemicals were banned by the U.S. Environmental Protection Agency (EPA) in 1979. However, PCBs are resistant to environmental degradation, so they can persist in the environment for decades. PCBs can build up in the fatty tissues of fish and other animals, and in high concentrations pose serious health risks to people who frequently eat contaminated fish.
According to the U.S. Centers for Disease Control (CDC), human health studies indicate that PCB exposure can disrupt reproductive function, and in utero exposure can lead to neurobehavioral and developmental deficits in newborns and continue through school-aged children. Other systemic effects, including liver disease and diabetes, and effects on the thyroid and immune systems are associated with elevated serum levels of PCBs. Increased cancer risks, including non-Hodgkinâ€™s lymphoma, are also associated with PCB exposures, the CDC says.
Several studies indicate that methylmercury is linked to subtle developmental deficits in children exposed to it before birth. Methylmercury exposure in adults has also been linked to increased risk of cardiovascular disease including heart attack.