The federal regulations governing emissions issued last year were the first mercury-specific controls required for permanently installed coal-fired power plants. However, the controls required for other pollutants — particulate matter, sulfur dioxide and nitrogen oxides — already remove about 40 percent, on average, of the mercury emitted by power plants.
Michigan is among 16 states and several activist groups that have filed suit in federal court seeking to force the Bush Administration to issue stricter regulatory controls on mercury emissions. According to Steve Chester, director of the Michigan Department of Environmental Quality, “The message being sent to the Environmental Protection Agency is that their proposal does too little, too late.”
Opponents are particularly critical of the cap-and-trade system, whereby a utility must either reduce mercury emissions to meet the control standard or purchase additional allowances from utilities that have exceeded their required reductions. However, as a candidate in 2002, Gov. Granholm endorsed a cap-and-trade program such as that adopted by the Bush Administration. As stated in her platform, the governor called for implementing “an approach, such as a cap and trading policy, that sets firm limits and timetables, while giving utilities the ability to incorporate pollution control into long-term investments and to capitalize on market incentives to reduce emissions cost effectively.”
Many of the commonly heard claims about mercury risks that underlie calls for stricter controls lack scientific validity. Four of these claims are examined below.
Claim: Many women of child-bearing age and young children are exposed to unsafe levels of mercury.
Fact: The most recent study by the U.S. Centers for Disease Control found that women of child-bearing age had mercury levels below the threshold associated with any adverse health effects. Moreover, the CDC found that mercury levels in human blood actually declined between 1999 and 2002. Only 6 percent of women of child-bearing age registered mercury concentrations that even fell within a factor of 10 of the level associated with health effects.
The CDC report also confirmed previous findings that no children have mercury levels that are even close to the level where health effects have been detected, and are not at risk from consuming seafood.
Claim: The effects of mercury on child development are “devastating.”
Fact: According to the EPA, the vast majority of children are totally unaffected by mercury, and the effects — even for the highest exposed individuals — are subtle. Only in accidental exposures where populations have been exposed to massive levels of methylmercury, have serious health effects been observed. It would be grossly misleading to infer that the effects observed from extremely high doses also occur at low exposures.
Claim: The best way to reduce mercury exposure is to eliminate mercury from the emissions of coal-fired power plants.
Fact: As numerous analyses have shown, the mercury deposited in Michigan comes from both natural sources and anthropogenic sources around the world. Coal-fired power plants in the United States produce only about 1 percent of global mercury emissions. According to the EPA, the emissions from power plants account for only about 10 percent of mercury depositions in the United States. Consequently, the elimination of mercury from power plant emissions will have a negligible effect on human health.
Claim: New federal regulations to control mercury emissions are insufficient to protect public health and the environment.
Fact: Under the federal “cap-and-trade” program, the EPA will allocate to each participating state an emissions allowance. States, in turn, will allocate emissions allowances to each coal-fired power plant. U.S. coal-fired power plants currently emit an estimated 48 tons of mercury annually. The federal program is designed to reduce these emissions in two phases. The first phase will cap mercury emissions at 38 tons nationwide in 2010. The second phase will cap emissions at 15 tons nationwide by 2018, which constitutes a reduction of nearly 70 percent from 1999 levels.
A utility must either reduce mercury emissions to meet its allowance or purchase additional allowances from utilities that have exceeded their required reductions. Based on industry economics, larger utilities are likely to have the access to capital necessary to undertake major emissions reductions and thus sell credits to smaller utilities. The flexibility of allowance trading creates financial incentives for utilities to look for new and low-cost ways to reduce emissions and to improve the effectiveness of pollution control equipment. In addition, the financial penalties for noncompliance are significant.
The phased approach also allows utilities to take advantage of emissions controls that must be installed by 2010 to reduce sulfur and nitrogen oxides. While these controls will reduce total mercury only modestly, they will substantially reduce the inorganic form of mercury that is of greatest concern for local deposition.