Nationally most mercury in all of our waterways, restriciting how much fish can be eaten in the lower 48 states, comes from coal power plants.
Gold Mining. California has gotten rid of coal plants and won’t buy electricity from coal plants out of state, but nevertheless there is mercury throughout the state, a ghastly legacy of the Gold Rush. Fish consumption levels (for women and children especially of bass, carp, and large brown trout should be limited, according to a state health advisory issued by the state Office of Environmental Health Hazard Assessment in August 2013.
Toxic vineyards? California vineyards may be raising the environmental levels of methylmercury, a known cause of developmental defects. A team at Stanford University in California found that the sulphur in anti-fungus sprays turns into sulphates, which may then convert inorganic mercury in the soil into organic methylmercury. Proceedings of the National Academy of Sciences.