According to the US Food and Drug Administration (FDA), the risk from mercury by eating fish and shellfish is not a health concern for most people. However, certain seafood contains sufficient mercury to harm an unborn baby or young child's developing nervous system. The FDA makes three recommendations for child-bearing women and young children: Do not eat shark, swordfish, king mackerel, or tilefish because they contain high levels of mercury. Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Four of the most commonly eaten fish that are low in mercury are canned light tuna, salmon, pollock, and catfish. Another commonly eaten fish, albacore ("white tuna") has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week. Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week. These recommendations are also advised when feeding fish and shellfish to young children, but in smaller portions. Mislabelling When the ocean conservation organization Oceana examined over 1,200 seafood samples of seafood sold in the U.S between 2010 and 2012, they found one-third were mislabelled. The highest rate of mislabelling occurred with snapper at 87 percent, followed by tuna at 57 percent. Persistent organic pollutants If fish and shellfish inhabit polluted waters, they can accumulate other toxic chemicals, particularly fat-soluble pollutants containing chlorine or bromine, dioxins or PCBs. Fish that is to be eaten should be caught in unpolluted water. Some organisations such as SeafoodWatch, RIKILT, Environmental Defense Fund, IMARES provide information on species that do not accumulate much toxins/metals. Parasites Parasites in fish are a natural occurrence and common. Though not a health concern in thoroughly cooked fish, parasites are a concern when consumers eat raw or lightly preserved fish such as sashimi, sushi, ceviche and gravlax. The popularity of such raw fish dishes makes it important for consumers to be aware of this risk. Raw fish should be frozen to an internal temperature of for at least 7 days to kill parasites, and home freezers may