Trace Elements in Fish and Fish Oil Supplements

For years, the American Heart Association has recommended eating an average of two to three fishmeals each week to help reduce cholesterol, high blood pressure, and hardening of arteries. Research shows that consuming fish increases high quality protein with fewer calories, and it is rich in omega-3 fatty acids. Omega-3 fatty acid helps to reduce the risk of coronary artery disease, helps in the treatment of bipolar disorder/depression, and helps reduce inflammation in autoimmune diseases (1,4). Fish are also low in sodium and a good source of potassium. Some examples of fatty, coldwater fish that are high in omega-3 fatty acids include salmon, mackerel, and herring. Unfortunately, due to industrial pollution, many fish have high levels of contaminants including mercury, methyl mercury, and PCBs (polychlorinated biphenyls), which are absorbed by surrounding waters and from foods they eat. Currently, the EPA limit for mercury in fish is 1 ppm. About 22% of all PCBs are in estuarine and coastal sediments, which accounts for 95% of the fish production (2). The EPA estimates up to 15% of mercury emissions from these utilities fall within 30 miles of a plant, and up to 50% falls within six hundred miles. The mercury bio-accumulates through the food chain and reaches the predator species. For example, a Nevada reservoir fish tissue sample shows an average of 0.47 ppm mercury; the EPA guidelines recommend limiting consumption of such fish to one 8-ounce meal per month for adults (3). For humans, mercury and methyl mercury are toxic and can damage the brain and the nervous system. Mercury poisoning symptoms include numbness in hands and feet, general muscle weakness, and vision, hearing, and speech damage. In extreme cases, insanity, paralysis, coma, and death follow. The U.S. Food and Drug Administration and the EPA advised pregnant women and those who might become pregnant to avoid certain fish known to be high in mercury. This study will investigate trace element concentrations including heavy metal concentrations in different types of fish and fish oil supplements available from local markets in New Jersey.