There’s trouble in paradise. Mercury levels in fish continue to rise and it’s almost impossible now to eat seafood that doesn’t contain at least a small amount of mercury in it.

The bad news is there are few fish that do not contain mercury. The good news is you can still eat fish if you do it in moderation and stay away from the fish that contain the highest levels. We’re not at the panic level and the federal government is not about to start banning certain fish for sale, but there are some things you can do to limit your intake of mercury.

Mercury levels go up with the food chain and this applies to mainly predatory fish; the larger the fish, the higher the mercury content. Swordfish, shark and the larger varieties of tuna contain the highest amounts of mercury in fish we consume. There are lots of reasons you shouldn’t eat shark and I won’t go into it all here, but suffice to say, the mercury levels alone are reason enough. As for swordfish and tuna, they are in peril of being fished out, so mercury is the best reason, but not the only one to limit their consumption.

Shellfish are inherently low in mercury, so lobster, crab, scallops, clams, mussels and shrimp are fairly safe. Good news for us, but you should still only eat it in moderation. Anchovies and sardines have some of the lowest levels.

As a sushi chef I have followed the mercury conundrum for some years now. Though there seems to be a heightened awareness of mercury, I don’t believe that consumers fully grasp the implications it has on seafood and our health. Consumers think, “They’re selling it, it must be okay.” For the most part, anyone who sells fish (especially predatory fish) is unaware of the mercury content of a particular variety.

And there is no regulation that says they have to be.

It begins with fossil fuels. Chemical producing and coal burning power plants are the biggest offenders. Mercury is released into the atmosphere and falls back to earth with rain.

The mercury makes its way into streams, lakes and the oceans. Being a heavy metal, it sinks. Bacteria go to work and convert it to methyl-mercury, which, by the way, is more toxic and makes it digestible. It enters your body as a neurotoxin. That means it affects your brain and nervous system.

Mercury in fish is not the first time humans have had to deal with the effects of a neurotoxin. Romans suffered the effects of lead with an extensive system of plumbing and boiling wine in lead pots as a way of sweetening it.

Puffer fish is a double whammy. Not only does it contain methyl-mercury, it produces a toxin that is deadly. Snake venom and insect stings are other forms of a neurotoxin.

Salmon is popular for a lot of reasons, mostly for its high Omega-3 content. It helps make for a healthy heart. A recent study reported in the New England Journal of Medicine stated that heart disease is not affected by mercury levels; however, you still need to be conscious of mercury levels in salmon. Stay away from farm-raised salmon. Best bet is to choose an Alaskan wild-caught salmon.

Most data on mercury in fish comes from two agencies. The Food and Drug Administration, which tests fish for mercury, and the Environmental Protection Agency, which determines mercury levels that it considers safe for women of childbearing age.

If you’re pregnant, or think you are about to become pregnant watch those levels closely. Better yet, remove fish from your diet completely. Mercury can be transferred through breast milk, so even after you deliver and are nursing, be careful. It has been documented that children can experience learning difficulties as result of their mothers’ fish consumption during pregnancy. The federal government has warned pregnant and nursing mothers against consuming fish.

If you have an iPhone, Apple makes it easy for you to determine if you are within safe limits in consuming fish.

The “Mercury In Fish” iPhone app makes it easy to choose fish low in mercury, and it can also help you keep track of your mercury level. At a restaurant, in the store, or at home, “Mercury In Fish” allows you to browse more than 125 of the most common culinary fish. You can track your mercury level in real-time as it automatically calculates your mercury level based on the FDA, EPA, and WHO standards. And it even comes with pictures.

For the immediate future, you’re screwed. There are no fish you can eat that doesn’t have some mercury contamination in it. For now, stay away from the big three: sword, shark and tuna. Pick your other choices carefully and don’t be afraid to ask questions. Eat more shellfish. 

And how much Mercury is considered bad? The following are what the National Resources Defense Council (NRDC) uses to determine Mercury levels from lowest to highest.

Least mercury: Less than 0.09 parts per million
Moderate mercury: From 0.09 to 0.29 parts per million
High mercury: From 0.3 to 0.49 parts per million
Highest mercury: More than .5 parts per million
 
Can it be fixed? Reducing mercury levels begins at home. Avoiding thermometers, thermostats, batteries and auto switches that contain mercury is a start. These wind up in waste dumps and eventually make their way into the ground. Maine only limits mercury in batteries at this time. The EPA continues to strengthen its regulations on particles released into the air from chemical, fuel and industrial applications.

Bottom line: We will run out of fish long before the mercury levels are brought under control. It’s a global problem and not confined to the good ole USA. China is the largest consumer of mercury in the world. Mercury released into the air in China can travel half way around the globe and deposit itself in our own lakes and steams. No one and no place is safe.

Sadly, controlling mercury is relegated to the political arena. We are years away from treaties that control mercury, even if we are making great strides on the home front. Stop eating swordfish, shark and tuna today. There are plenty of other fish that are just as good with lower mercury levels. This doesn’t mean if you have one of the Big Three tonight or even next week you’re going to die. That’s not how it works. But, once mercury is in your system it doesn’t go away. It only builds, so it makes sense to avoid the higher contaminates. Long after you are dead and in your grave for a hundred years, your mercury levels will still be the same. It’s a savings account you don’t need.