Government Scientists Find Mercury in Every Fish Tested

By Eliza Strickland | August 20, 2009 10:16 am

graylingA study that set out to determine the how many of the fish in our nation’s streams are contaminated with mercury came back with an ominous answer: quite possibly, all of them. Researchers from the U.S. Geological Survey sampled 34 species of fish at 291 stream sites across the country, and found mercury in every single fish they tested. “This study shows just how widespread mercury pollution has become in our air, watersheds, and many of our fish in freshwater streams,” U.S. Interior Secretary Ken Salazar said [Los Angeles Times].

A quarter of the fish had mercury levels that are considered unsafe for people who eat fish regularly, according to the Interior Department. The main source of mercury to most of the streams tested, according to the researchers, is emissions from coal-fired power plants. The mercury released from smokestacks rains down into waterways, where natural processes convert it into methylmercury — a form that allows the toxin to wind its way up the food chain into fish [AP]. But fish with high mercury levels were also found in Western areas that have been mined for gold or mercury.

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Image: flickr / kasperbs

CATEGORIZED UNDER: Health & Medicine, Living World
MORE ABOUT: fish, pollution, rivers, toxins
  • Christina Viering

    Disturbing find.

  • nparikh

    Does this apply to fish derived products like fish oil?

  • Tizzle

    Every fish tested in American streams. That doesn’t sound like it includes the oceans. Am I reading it too quickly?

  • Carter

    Tizzle – It’s likely that if every fish in the US is contaminated to some level, and that all bodies of moving water (save for the tributaries of the Great Salt Lake) feed into the ocean, it’s reasonable to say that despite the ocean being a very large reservoir capable of dilution that coastal waters would also be contaminated as well.

  • Ugly American

    When you think Coal Power, think Mercury Pollution.

    Coal Power also gives us a rain of Radioactive Uranium & Thorium soot.

    Go look it up.

  • Oster Itch

    Ugly, I just hope you don’t live in California where China’s soot eventually falls. I’d stick my head in the sand, but I am afraid of Radon too.

  • Bob

    It’s not that disturbing. You’d have to eat 100’s of ounces of fish PER WEEK to ever be in any danger.

  • JustinTheOregonian

    Bob-There are plenty of Native peoples who eat enough fish that this could pose a potential danger. And it is pretty disturbing that mercury is that widespread and common in freshwater ecosystems. Just another reason to switch from coal.

  • pdunnz

    This finding makes clean coal technology sound more difficult than ever. Clean coal technology researched during the seventies and eighties focused on reducing acid rain reduction by removing sulphur. Does the new clean coal emphasize lowering greenhouse gases or mercury reduction or …? Bob, do all fish accumulate mercury at the same rate. Or did the study address bioaccumulation rates are affected by the niche on the food chain that fish represents.

  • Tommy

    This is fuzzy study. ALL FISH HAVE A INHERENT AMOUNT OF MERCURY IN THEM..for most it is a small amount. No mention of base amounts. Just a shocking idea and open ended statement about mercury in fish!?!?!?!?!

  • Dustin

    One thing this study might be showcasing is just how sensitive our tests have become. Or it might be showing that there is a real danger. Hard to tell without them showing the test data.

  • earthbutcher

    Bob, do you work for a power plant? As per the U.S. Dept of the Interior’s news release:

    “About a quarter of these fish were found to contain mercury at levels exceeding the criterion for the protection of people who consume AVERAGE amounts of fish…” (Capitalization emphasis mine)

    Feel free to consume a couple of these fish per week for a year and get back to us about how you’re doing. Assuming you can still keyboard after the year is up.

    And Tommy and Dustin, you must already be eating these fish. There was nothing fuzzy about the study, as you’d know if you bothered to follow (and read) the links provided. I’ll give you a little summary from the survey about inherent mercury: fish in the continental U.S. exhibit mercury levels 3 to 4 times higher than pre-industrial levels.

    For those of you aren’t so mercury-contaminated you can still read, here’s a nice little FAQ about the study:

  • Jorge


    That sucks big time.

    Who would have think that 50 years ago?


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