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Frequently Asked Questions about Mercury in Fish and Shellfish:

1. What is mercury and methylmercury?
2. I'm a woman who could have children but I'm not pregnant - so why should I be concerned about methylmercury?
3. Is there methylmercury in all fish and shellfish?
4. I don't see the fish I eat in the advisory. What should I do?
5. What about fish sticks and fast food sandwiches?
6. The advice about canned tuna is in the advisory, but what's the advice about tuna steaks?
7. What if I eat more than the recommended amount of fish and shellfish in a week?
8. Where do I get information about the safety of fish caught recreationally by family or friends?

1. What is mercury and methylmercury?

Mercury occurs naturally in the environment and can also be released into the air through industrial pollution. Mercury falls from the air and can accumulate in streams and oceans and is turned into methylmercury in the water. It is this type of mercury that can be harmful to your unborn baby and young child. Fish absorb the methylmercury as they feed in these waters and so it builds up in them. It builds up more in some types of fish and shellfish than others, depending on what the fish eat, which is why the levels vary.

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2. I'm a woman who could have children but I'm not pregnant - so why should I be concerned about methylmercury?

If you regularly eat types of fish that are high in methylmercury, it can accumulate in your blood stream over time. Methylmercury is removed from the body naturally, but it may take over a year for the levels to drop significantly. Thus, it may be present in a woman even before she becomes pregnant. This is the reason why women who are trying to become pregnant should also avoid eating certain types of fish.

3. Is there methylmercury in all fish and shellfish?

Nearly all fish and shellfish contain traces of methylmercury. However, larger fish that have lived longer have the highest levels of methylmercury because they've had more time to accumulate it. These large fish (swordfish, shark, king mackerel and tilefish) pose the greatest risk. Other types of fish and shellfish may be eaten in the amounts recommended by FDA and EPA.

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