Methylmercury and fish you can safely eat

Methylmercury is a metal that can be found in some fish and shellfish. Mercury occurs naturally in the environment and can also be released into the air through industrial pollution. It falls from the air and can collect in streams, rivers and oceans. Microorganisms transforms mercury into methylmercury. Fish absorb methylmercury as they feed. Larger fish that have lived longer have the highest levels of methylmercury because they have had more time to accumulate it. Methylmercury can be toxic, especially to unborn babies, and this is why certain fish should be avoided when you are pregnant. Research done in 2014 also found that women exposed to mercury had higher autoimmunity markers.

These fish can contain high levels of methylmercury:

• swordfish
• tilefish
• king mackerel
• shark (flake)
• ray
• barramundi
• gemfish
• orange roughy
• ling
• southern bluefin tuna

It's okay to eat other cooked fish/seafood as long as you select a variety of other kinds while you're pregnant or trying to become pregnant. You can eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in methylmercury. Five of the most commonly eaten fish and shellfish that are low in methylmercury are shrimp, canned light tuna, salmon, pollock, and catfish. *

Fish that contain lower levels of mercury include:

• Shellfish including prawns, lobsters and oysters
• Salmon
• Canned tuna

* U.S. Food and Drug Administration