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Mercury emissions are worse than CO2, but OK with the Supreme Court

REUTERS/Ina Fassbender
A reduction in coal burning is in order.

A new Supreme Court decision is restricting the Environmental Protection Agency’s ability to limit emissions of carcinogenic mercury, which results from coal burning. Where does that leave President Barack Obama’s Clean Power Plan? That plan is focused on limiting coal-burning emissions of carbon dioxide (CO2), an invisible non-toxic trace gas that is an essential plant food, and with dangers less certain than those from mercury.

The high court’s June 29 decision [PDF] focused on the EPA’s failure to do a cost benefit analysis of its regulation.

“It is not rational to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits,” Justice Antonin Scalia wrote in the majority opinion. The opinion remanded the case to a lower court for a further review into how costs should be considered in the EPA’s rule making.

Costs and benefits in dispute

The actual costs and benefits of mercury emissions and regulations are in dispute. The annual costs of compliance under the rule are generally estimated at $9 billion to $10 billion, but utility industry analysts estimate the annual benefits of reducing emissions of mercury and other hazardous air pollutants amount to only $4 million to $6 million.

The EPA and environmental groups estimate the benefits to be at least $37 billion, a figure that includes costs related to an estimated 11,000 premature deaths and more than a half-million lost days of work each year. Sorting out this huge opinion difference will not be simple. It will be even more difficult when Obama’s Clean Power Plan attempts to restrict CO2 emissions from electric power plants, an even more expensive process than controlling mercury emissions. 

We humans have inhaled and exhaled CO2 with every breath since before Homo sapiens walked the earth. On the other hand, ingesting even a few grams of mercury is not recommended. If the Supreme Court wants a thorough economic analysis before permitting mercury controls, I suggest the chances are slim for court approval of billions for control of CO2, a trace gas that is one part in 2,500 in the earth’s atmosphere. 

Risks aren’t worth taking

Our industrial activity is emitting more than 30 billion tons of CO2 each year. John Abraham, thermal sciences professor at the University of St. Thomas notes that future consequences of global warming will include lower crop yields, especially in areas of subsistence farming; ocean acidification; redistribution of water; and more extreme weather, with fewer but stronger hurricanes. Although others disagree with these conclusions, the risks Abraham describes are not worth taking, and a reduction in coal burning is in order.

Rolf Westgard is a professional member of the Geological Society of America and is a guest faculty member on energy subjects for the University of Minnesota’s Lifelong Learning program

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Correction: An earlier version of this commentary incorrectly stated global temperature trends in the 21st century.

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Comments (8)

  1. Submitted by Neal Rovick on 07/07/2015 - 09:00 am.

    Neither mercury emissions or CO2 are good.

    But the evidence and science all point out that the consequences of the excess CO2 emissions will be far more costly and widely damaging to the world as we need it than mercury ever would be.

  2. Submitted by joe smith on 07/07/2015 - 09:16 am.

    The “Go Green” gang backed the wrong horse in the let’s scare the hell out of the public race. They had me concerned years ago with the mercury/acid rain issue. When they went to CO2 they lost me.
    Now I am waiting on pins and needles until the ocean releases all the heat it absorbed to stop global warming and unleashes total devastation on our planet. I want to worry about polar bears, ice caps and glaciers but the trapped heat has my attention.

  3. Submitted by Joe Smithers on 07/07/2015 - 11:08 am.

    About time

    It’s about time someone writes about this. Far to much blame for our polluted waters has been placed on agriculture when mercury is the #1 cause of impaired waters in MN according to the MPCA. Our governor has been ignoring this in his smear campaign against agriculture so he can hopefully have more pheasants to hunt.

  4. Submitted by Joel Stegner on 07/07/2015 - 11:17 am.

    To the Supreme Court, business profits are all important

    There is a scientific consensus that mercury is toxic, but the energy industry claims the impact is only in the 4-6 million dollar range. Then Antonin Scalia (neither a scientist or a justice in my opinion) says: “It is not rational to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits,” seemingly “buying” the corporate assessment.

    Let’s just talk about the idea of people getting sick and dying from mercury exposure. How many lives combine to be worth 4-6 million dollars? Since corporations have stripped away most of people’s assets and their ability to work, maybe corporation just don’t think human life of the “other people” who suffer the effects have much value.

    On the other hand, the environmentalists are claiming $37 billion in negative effects, nearly four times the costs as the extra profits energy companies gain by not having to pay to remove mercury emissions from their smoke stacks. Just another example of the American public carrying an extra financial and health burden to enrich the investor class. Elect a Republican President and get more “justices” like Scalia, and just get used to sucking up whatever junk industry decides it wants to dump into our air and water.

  5. Submitted by Rachel Kahler on 07/07/2015 - 12:46 pm.


    I have to nitpick first–it is impossible for a single human to draw breath (containing CO2 or mercury or anything else) before Homo sapiens existed. In light of that wildly inaccurate claim, it’s hard to take the rest of it without vast amounts of salt–undoubtedly recovered from desalination of the over acidified oceans in order to satisfy the thirst of heat and drought stricken regions as a result of increased global temperatures.

    That said, I fully appreciate that SCOTUS made the wrong call here (and I know that’s not the author’s point–I suspect the point is some confused ‘I told you so’). Even if the cost-benefit analysis is what they bought from the energy industry, the profit of any company should never come over the life, liberty and pursuit of happiness of any individual citizen. That is, the federal government has power under the Constitution to impose regulations that affect the health of its citizens. Both mercury and CO2 have well established harms to the citizenry of not only the USA, but to the human species as a whole, not to mention pretty much every other animal on the planet.

    Finally, probably the biggest reason the Obama administration emphasized CO2 over mercury is because CO2 is more central to the American consciousness right now. If the focus was mercury, most Americans would probably be confused. The mercury story has been tainted by the ridiculous honking of the anti-vaxxers. While there is pretty much zero risk of harm by mercury from vaccines, there actually is risk as a result of mercury exposure in the air and in the water. But, if the focus becomes mercury again, the dichotomy of the argument would dilute the problem. And because the problem is directly linked to both mercury and CO2, the smart target (and still a correct target) is CO2.

  6. Submitted by Robert Moffitt on 07/07/2015 - 03:57 pm.

    It’s about process, not policy

    The Supreme Court did not overturn the EPA’s mercury rule, nor did they prevent the rule from removing “co-benefit” pollutants like particulates. Many coal plants have already upgraded their facilities to reduce mercury, others will likely do the same. The court ordered the EPA to go back to the appellate court and tweak the details of when and how the cost benefit analysis will be done.

    In fact, the EPA DID do a cost analysis on the mercury rule, but SCOTUS felt it was done too late in the process.

    So this is really a decision about process, not policy.

    I suspect the Clean Coal Plan will proceed as expected. As Rolf says, a reduction in coal burning is in order.

  7. Submitted by Jay Willemssen on 07/07/2015 - 05:39 pm.

    H20 is essential to life, too

    Best not consume too much of it, though.

    Also, a trace amount of plutonium can kill a person. Its concentration is basically irrelevant.

    Let’s all work to make better arguments against climate change theory now, shall we?

    “carbon dioxide (CO2), an invisible non-toxic trace gas that is an essential plant food”
    “CO2, a trace gas that is one part in 2,500 in the earth’s atmosphere”

  8. Submitted by rolf westgard on 07/08/2015 - 07:32 am.


    As Paracelsus once said, the difference between a therapy and a poison is the dose.

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