Donner Lake - PCBs
Mercury, polychlorinated biphenyls (PCBs) and several other chemicals were analyzed in edible tissues of four fish species caught from Donner Lake, Nevada County, California. The contaminant data were evaluated by the Office of Environmental Health Hazard Assessment (OEHHA) to determine whether there may be potential adverse health effects associated with the consumption of certain sport fish from this lake. OEHHA determined that mercury and PCBs were the two chemicals of concern if fish caught in this lake and nearby creeks were eaten regularly.
Mercury is a trace metal that occurs naturally in the environment and is also redistributed as a result of human activities such as mining and the burning of fossil fuels. In aquatic systems, it undergoes chemical transformation to the more toxic organic form, methylmercury, which accumulates in fish and other organisms. Methylmercury can be toxic to humans, especially the developing fetuses and young children, because the critical target of toxicity is the nervous system. PCBs are man-made chemicals used mainly in electrical equipment and plastics. They were banned in the 1970s but do not break down easily in the environment and can accumulate in fish. PCBs may cause cancer or other health effects in humans. The risk associated with eating fish containing these chemicals depends on the toxicity of the chemicals and the exposure level. Based on this evaluation, OEHHA developed safe eating guidelines for these chemicals in fish caught from this lake and surrounding creeks.
- Health Advisory and Safe Eating Guidelines for Fish from Donner Lake (Nevada County, CA), January 2011
California Office of Environmental Health Hazard Assessment (OEHHA), Sacramento, CA
- Donner Lake Frequently Asked Questions, January 2011
California Office of Environmental Health Hazard Assessment, Sacramento, CA
- Data file - Donner Lake fish tissue chemistry, 2002-2007 (MS-Excel)