Anglers are advised to avoid eating channel catfish and limit their consumption of black bass and rainbow trout caught in the north lake at San Francisco’s Lake Merced because of concerns about mercury and polychlorinated biphenyls, or PCBs.
The guidelines about black bass and rainbow trout do not apply to Lake Merced’s south lake.
People from age 18 to their mid 40s can safely eat up to seven 8-ounce servings of rainbow trout from the lake per week, according to the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment.
Men in that age range can safely eat one serving of black bass, but women in that age range should avoid black bass. Channel catfish from the south lake of Lake Merced should also be avoided.
Mercury is a naturally occurring metal with industrial uses that accumulates in fish and can cause damage to the brain and nervous systems of children and fetuses.
Despite being banned in the 1970s, PCBs are still found in fish and exposure is believed to cause cancer in animals.
The recommendations are site-specific for Lake Merced, according to the state EPA. The agency issues site-specific advisories for bodies of water where people catch and eat fish in California.