Scientists think it could reduce some of the risk of eating fish with still-climbing mercury levels.

CNN: Beware of shark meat, FDA warns

You can get comparison info on elementary schools in your city, smartphones and mercury levels in fish, to name a few.

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Meanwhile, data collected over eight years by Penn State University for the Pennsylvania Department of Environmental Protection show mercury levels 47 percent higher in areas closer to power plants.

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While a certain amount of mercury in the environment is natural, a growing worldwide pollution, especially of our oceans, appears to be increasing the risk of high mercury levels in some of the fish we eat.

CNN: Beware of shark meat, FDA warns

"What we found for our 124 sharks that we sampled was that about one-third of them came in with mercury levels that were over the Food and Drug Administration's action level of one part per million, " said Hueter.

CNN: Beware of shark meat, FDA warns

Currently, millions of people worldwide are exposed to dangerously high levels of mercury due to industrial waste.

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Shark meat, however, is not the first seafood to carry a warning for increased levels of mercury.

CNN: Beware of shark meat, FDA warns

Levels of mercury in fish other than shark, swordfish and marlin did not give cause for concern.

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Workers may be exposed to very high levels of mercury when that happens.

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Eating shark meat may expose you to potentially dangerous, high levels of the metal mercury.

CNN: Beware of shark meat, FDA warns

Greenpeace said samples of the sludge it took on Tuesday contained "surprisingly high" levels of arsenic and mercury.

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In fact large fish like sharks, tuna and swordfish feed on smaller fish and can accumulate high levels of environmental pollutants like mercury.

CNN: Beware of shark meat, FDA warns

The Rule sets the mercury and acid gas emission limits for new facilities below levels that can accurately be monitored.

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By hatching its own fish, carefully controlling feed and raising fish offshore in clean water, mercury and other pollutants can be kept to extremely low levels, contends Spencer.

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Another characteristic, it added, was that mercury became more concentrated as it moved up the food chain, reaching its highest levels in predator fish that could be consumed by humans.

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Another characteristic is that mercury becomes more concentrated as it moves up the food chain, reaching its highest levels in predator fish that may be consumed by humans, the report adds.

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