The controversy about federal mercury standards embodies all of the features of most environmental disputes and demonstrates practical difficulties in implementing effective measures to protect health and the environment.
Mercury is a heavy metal that can be harmful to humans. The danger is particularly high for young children and for developing fetuses in pregnant women. High levels of mercury can inhibit brain development and neurological functioning. So, the danger of putting more mercury into the environment seems clear.
Mercury enters the environment through natural events such as volcanic eruptions and erosion of rocks containing the element. Some comes from incinerating waste that contains mercury batteries, used thermostats or other varied electrical switches. Early pairs of flashing sneakers contained mercury, for example.
Burning coal that contains traces of mercury is another major source and lies at the heart of the current controversy.
For years, there were no specific standards to reduce mercury emissions from coal-burning power plants. Just weeks before leaving office, the Clinton administration issued rules requiring coal plants to install “maximum achievable control technology” to reduce mercury emissions. The Bush administration put those rules on hold.
The U.S. Environmental Protection Agency recently announced a different requirement. Emissions will be subject to a tradable permit system that will gradually ratchet down allowable levels.
Existing plants will get permits to emit mercury in some relation to current levels. If they choose to reduce their emissions, they can sell their permit to someone else. Anyone building a new facility will have to eliminate mercury emissions or buy existing permits equal to contemplated emissions.
Given just this information, public opinion is sharply divided. Economists and many serious environmentalists think the tradable permit system is the better option.
Economic theory shows that tradable permits achieve larger pollution reductions at lower cost than the command-and-control “best technology” approach the United States has favored in the last three decades. Moreover, years of extensive experience with emissions permits in European countries that take a less litigious and rules-oriented approach to environmental protection overwhelmingly bear that conclusion out.
It is not a liberal-conservative issue. Economists who are left-wing Democrats or socialists agree that tradable permits or emissions taxes are the best solution. Many policy researchers for mainstream environmental groups agree. Economists have failed, however, to convince the public.
There is a catch in the current controversy, however, even for economists who like tradable permits. A well-designed permit system must reduce emissions to levels where the benefits to society of further reductions would be less than the costs to society of the same. Introducing a permit system that keeps emissions at levels well above that point is a deceptive travesty.
That may well be what the Bush Administration is doing in this case. Estimated reductions under the new rules will result in much smaller emission reductions much later in time than the Clinton plan might have achieved. If true, the plan is simple dishonesty disguised in good economics.
Again, given information available so far, many economists would say, “Keep the Bush tradable permits system but reduce the permitted amounts and you will have an optimal policy.”
Even if one does not buy that argument, there are more catches. Were estimated Clinton-policy reductions realistic or necessary?
Historically, estimates of emissions reductions with “best technology,” such as those made by Clinton’s EPA, turn out to be very inexact after the fact. Mercury reduction technology is still in its infancy. Experience says that it is likely to be less effective or more expensive than estimated.
Also, once the EPA blesses a particular technology as the best available, there is little economic incentive for further research, and technological innovation is frozen in place. European countries with permit systems see much more ongoing refinement of emissions control technology because improvements allow firms to sell valuable permits.
More importantly, there is legitimate debate about what levels of mercury cause harm and alternative methods of reducing human exposure.
Mercury is an anomaly in that the EPA threshold for harm is only a fifth of that used by the Food and Drug Administration and the World Health Organization. Most other industrialized nations have standards similar to those of the WHO. If the rest of the world — including the FDA — is right, then the social benefits of reducing mercury emissions from power plants are lower than the EPA estimates.
People want clear right-wrong answers to policy questions. These are rare in the real world. Mercury does “bio-accumulate” in fish, and pregnant women may be harmed by eating too much fish of certain species or from certain bodies of water.
At the same time, good scientific studies show that more than 70 percent of the mercury in people’s bodies comes from mercury-silver amalgam tooth fillings.
Dentists will tell you that amalgam fillings are perfectly safe. According to the FDA and over a century of experience, they are right.
Still, some experts argue that if you want to reduce harm to fetuses from mercury, the easiest approach is removing amalgam fillings in women contemplating pregnancy. Don’t use amalgam in the teeth of any female until after her childbearing years.
No clear consensus exists on this, but it is not a lunatic fringe position in the scientific community.
Environmental policy — it isn’t as simple as it looks.
© 2004 Edward Lotterman
Chanarambie Consulting, Inc.