Mercury Rising

TunaBy Debra Chase

If I encouraged the use of an old favorite tuna sandwich recipe it could very well poison anyone that ate it. The fish considered to be the greatest athlete of the ocean, a sushi chef’s dream and a favorite of pescatarians across the globe, is not just threatened by extreme overfishing, it is also considered to be highly contaminated by mercury along with all other species of tuna.

Adapted for speed, its only enemies are the largest and fastest of hunters, it can gain speeds of over 50 miles an hour and can cross the oceans depths many times. Warm blooded, its strong muscles and crescent shaped tail, with eyes that are flat against its torpedo shaped head, allows for almost friction free swift movement. It can dive over 250 meters in less than a minute. The tiger of the ocean, so named not just for its magnificent size (some of the oldest adults reach over 6 feet long and 900 lbs or more) and speed, but for it voracious appetite in searching out prey in the deepest depths of the ocean. Blue Fin eat all manner of fish and the only thing that eats them are sharks, whales and humans. Currently endangered, it’s estimated that only 40,000 of adult Pacific and southern blue fin tuna are still in the wild.

Greenpeace states: “Populations of all three species of the magnificent blue fin tunas, the most iconic and commercially valuable of all tuna species, are on the brink of collapse. Atlantic blue fin is listed on the IUCN Red List of Threatened Species as Endangered and southern blue fin as Critically Endangered. Pacific bluefin has less than 5%, of its population left, similar to southern blue fin. And yet we keep fishing them”!

In an ironic twist, levels of mercury in tuna have risen by more than 4% a year since 1998, according to a study recently published by Michigan University researchers. It is noted that the rise is consistent with the “load” of contaminates that are dumped into the oceans, primarily emissions from coal fired power plants. Fish studied by the researchers in the deep waters of the Pacific near Hawaii were found to have mercury levels long considered unsafe for human consumption. Yet, for obvious political reasons, in a nod to the fishing industry, the FDA has determined that the use restrictions on albacore tuna are to be loosened, going so far as to recommend that pregnant women and children can continue to eat the fish. According to Consumer Reports the allowed levels of any kind of tuna for human consumption should be tightened not loosened, as the FDA wants to do and, they are recommending that all women and children stop eating tuna period.

“We believe the FDA should advise stricter limits on tuna consumption and educate people about other fish that have health benefits without the risks,” says Jean Halloran, director of food policy initiatives for Consumers Union, the advocacy arm of Consumer Reports. “It isn’t simple, but that’s no excuse for the FDA to throw up its hands and give no help to pregnant women who may have a toddler to feed and a family to cook for.”

Humans are its biggest threat, not only as hunters but as an environmental hazard. The pollutants created by human activity are dumping more and more mercury pollution into the oceans and the tuna have no defense. Air pollution is the main cause of mercury contamination in the ocean, and burning coal represents 84% of that pollution. It falls in the rain and contaminates our rivers, streams, lakes and oceans. It is emitted from power plants and other industrial complexes that burn fossil fuels.

The larger and older the fish, the more mercury it is consuming and this translates into more mercury consumed by humans. Ironically, these larger fish are the ones that are commanding prices of one million dollars or more. The Japanese people eat more than 80% of the tuna caught and a purchase in Tokyo in June of 2013 commanded an astonishing price of $1.8 million for a 489 pound bluefin tuna. That’s about $4000 dollars a pound. Despite efforts by environmentally conscious chefs, NGOs and the US Government, the slaughter of these magnificent fish continues.

Methylmercury is a highly toxic form of mercury that builds up in fish, shellfish, and animals that eat fish. When humans eat these creatures they are exposed to it, and poisoning by methylmercury causes damage to the brain, kidneys and lungs and, depending on the level of exposure, will cause tremors, irritability, and mental instability (remember the mad hatters)? In infants and children, severe brain damage is guaranteed, which is why pregnant women and children should not eat it.

Now more than ever the call to end coal powered energy and the destruction of ocean species is at a desperate level. As Lewis Carroll said, “If you drink much from a bottle marked ‘poison’ it is certain to disagree with you sooner or later.”

About The Author

Disclaimer: the views expressed by guest writers are strictly those of the author and may not reflect the views of the Vanguard, its editor, or its editorial board.

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  1. Frankly

    Oh my oh my.  The author is so exited about this target-rich environmental activist topic that she cannot stay on point.  Is it over-fishing, or mercury from those coal-fired energy plants that she wants us to focus on?

    Or is it just the typical environmental extremist message that man and industrialism are evil and both must be eliminated to save the environment?

    It is too bad that the author didn’t focus on a single point here.  I certainly have concerns about the over-fishing of tuna, and the rise of mercury levels.   But the tone of this piece is just a big turn off being the standard man-is-bad, business-is-bad, and those that sound the alarms are the elite stewards of global righteousness.

    Also, screaming at the wall won’t help.  The author should have also done some research on Bluefin Tuna farming. The author should have also done some research on the rise of LNG replacing coal because of the benefits of free market capitalism.  And there is a push for more nuclear power generation.  But my guess is that the author is also against fracking and nuclear.  And I’m sure she has a problem with attempts to farm tuna.  Maybe I am wrong.   But, unfortunately that is the common bit from the environmental activists… to be against everything except some utopian natural state that is unattainable and highly irrational.

  2. debra

    I concede that sometimes it can be difficult to follow two trains of thought at one time, everyone is so busy it can be tough to read.

    In this article there are three thoughts expressed: 1, overfishing is causing the severe decline of tuna, 2. coal fired power plants are a major contributor to mercury poisoning and 3. mercury pollution is primarily caused by coal fired power plants and it is poisoning the fish and the people that eat the fish.

    I am wary of so-called solutions to environmental issues like farming fish to mitigate the over catch of wild fish. This is not a sustainable practice nor is it a healthy one because it does not solve the problem of the mercury dumped into the ocean and it causes other problems.

    Here are 9 reasons that farming fish is a bad idea:

    1. The Omega-3 Levels and other Health Benefits Are Not What You Think _ The farmed fish is not as healthy as a wild fish.
    2. Small Prey Fish May Be Driven to Extinction – Tuna eat a lot and they don’t do well on “feed”
    3. Farmed Fish May Spread Disease to Wild Fish
    4. Fish Farms Pollute the Environment and Damage Local Ecosystems
    5. Fish Feces Harm Coral Reefs
    6. Farmed Fish Escape
    7. The Jevons Paradox in Practice (The Jevons Paradox says that “as production methods grow more efficient, demand for resources actually increases”)
    8. Revenues Can’t Offset the Heavy Environmental Costs

    The scientific consensus accepts global warming is occurring. We would all be wise to act in response to this consensus by drastically reducing our use of fossil fuels, including natural gas, (which still pumps too much CO2 in the atmosphere)  and our consumption of other species of life.

    1. Frankly

      Thanks for responding.  So, you are against people eating wild fish, and against people eating farmed fish.  Are you against people eating fish in general, or are you wanting more fish-eating people to die off so there is a better balance of fish-to-people?

      I’m just guessing here, but you probably have a problem with people eating livestock too.

      Should we just strive for a smaller global population that survives on organic wild tubers and sustainable wild rodents (because they seem to replenish very well) and live in huts and clothing made of hemp, and get all of our power from sunlight and wind?

      If we drastically reduce our fossil fuels, a lot of people will die.  You do know that it takes a lot of natural gas to make fertilizer don’t you?  How do you suggest we feed the world after we have to stop eating fish, and beef, pork, lamb and chicken… and stop using natural gas?  What do you suggest we do to heat the homes of families living in cold climates?

      I’m not trying to be disrespectful here… I really want to understand your vision for that vision of utopia where the natural world is in perfect harmony.

  3. tribeUSA

    Coal plants in the USA have EPA-mandated mercury emissions control technology. Its my understanding that such technology is expensive, and that many countries like China do not have this (along with other scrubber and emissions technologies)–since mercury & soot from coal plant emissions is slowly poisoning much of China, I’d anticipate that in the coming decades China will have mercury control technologies as well–of course not only tuna are affected, but many other species as well (because of bioaccumulation; apex predators including humans tend to be most severely exposed via ingestion routes).

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