Anyone who eats fish that contain mercury and PCBs may suffer possible health problems, but fetuses and young children are at greatest risk. These chemicals are toxic to the brain, so exposure early in life when the brain is still developing can lead to IQ loss or changes in learning and behavior [6,7].

Because mercury and especially PCBs remain in the body, reflecting months or years of past exposure, any woman capable of bearing children needs to pay attention to the fish she eats, even before becoming pregnant [8]. During pregnancy these toxins travel easily through the placenta to the developing fetus. Mothers also pass these pollutants in breast milk to nursing babies. Since brain development continues into the teen years, children under 15 should also follow these guidelines.

According to the Environmental Protection Agency, nearly 16 percent of women of childbearing age have mercury in their bodies at levels that might harm the developing fetus [9]. In a given year, this exposure puts an estimated 630,000 newborns at risk for adverse health effects on their developing brains, mostly due to maternal fish consumption.

Even though fetuses and young children are at highest risk for health effects from fish contaminants, men, teenagers and women past childbearing years also need to be conscious of consuming fish lower in contaminants.