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Department of Health Services

Environmental Health



Fish continues to be an important part of our diet. They are an excellent source of protein, are low in saturated fats and contain omega 3 fatty acids that can reduce your risk for heart disease and improve how the brain develops in unborn babies and children.

Fish can also contain toxic chemicals from the water in which they live and the food they eat. Because of this the US Environmental Protection Agency and the US Food and Drug Administration (FDA) developed guidelines for safe consumption. The California Environmental Protection Agency (EPA) Office of Environmental Health Hazard Assessment (OEHHA) also provides guidance including fish consumption advisories or eating guidelines that are specific for certain sites.


Women Age 18-45, Pregnant and Breastfeeding Women, and Children Age 1-17 Years

When OEHHA's site specific advisories are to protect against mercury contamination, OEHHA recommends eating lower amounts for women age 18-45 and children age 1-17 years. Some chemicals may be passed on to the unborn child through the placenta or to the newborn through the mother's milk. Babies and children are more affected by mercury because their brains are still developing. Following the advisories is therefore especially important for this special risk group. However, if a source does not have a site specific advisory, the US EPA and US FDA recommends women of childbearing age and children consume no more than 1 fish per week.

Sport Fishing

Some fish you catch may take in toxic chemicals from the food they eat. Some of these chemicals build up in the fish over time. Although the levels found are usually low, large amounts may be harmful. It is a good idea to follow precautions when eating fish, particularly if you eat fish often.

Fish containing high concentrations of contaminants have been found in some of the popular sport fishing locations in Sonoma County. The Office of Environmental Health Hazard Assessment (OEHHA) has issued fish consumption advisories for Lake Sonoma and has collected data for Bodega Harbor and Spring Lake. A recent study and report from the State Water Resources Control Board, Surface Water Ambient Monitoring Program (SWAMP) has also identified preliminary indications that fish from the Laguna De Santa Rosa have been found to have higher concentrations of contaminants. OEHHA provides advice and "safe eating guidelines," to help you to make healthy choices when eating fish.

State Water Resources Control Board, SWAMP Study

On May 22, 2013, the State Water Resources Control Board, SWAMP published a study titled "Contaminants in Fish From California Rivers and Streams, 2011", which describes the results of a screening survey of contaminants in sport fish in California rivers and streams. During this study sport fish were sampled from popular fishing areas throughout the state and tested for contaminants. The Laguna De Santa Rosa was included in this study and showed a higher concentration of methyl mercury.

This was a preliminary survey to determine the need for further testing and identify the status of beneficial uses of fishing. There is inherent variability when testing levels of chemicals in fish and many fish need to be tested to determine a reliable level for a site advisory if appropriate. Unfortunately, this study provides levels based on test results from relatively few fish and this data is not sufficient for OEHHA to develop consumption advisories specific to these sites. The one site in Sonoma County that does have site specific consumption advisories is Lake Sonoma.

Office of Environmental Health Hazard Assessment, Health Advisory and Guidelines

On August 1, 2013, the Office of Environmental Health Hazard Assessment (OEHHA) released the “Statewide Health Advisory and Guidelines for Eating Fish from California’s Lakes and Reservoirs without Site-Specific Advice”. This is the first statewide advisory for California which OEHHA developed to help people make healthy choices about which fish to eat at lakes and reservoirs without advisories. For more information about this advisory please visit the OEHHA web site.


General Health Advice for People Catching and Eating Sport Fish in California
Source: California Environmental Protection Agency Office of Environmental Health Hazard Assessment.

Advice for Women of Childbearing Years and Children
Source: California Environmental Protection Agency Office of Environmental Health Hazard Assessment.

What You Need to Know about Mercury in Fish and Shellfish
U.S. Environmental Protection Agency.

Report: Contaminants in Fish from California Rivers and Streams, 2011 (pdf)
Source: State Water Resources Control Board, Surface Water Ambient Monitoring Program.