Proposed EPA Mercury Rule Garners Comments, Controversy

Published September 1, 2004

The public comment period for the U.S. Environmental Protection Agency’s proposed power plant mercury rule closed on June 29 after much controversy. Most of the record-breaking 600,000 comments came from environmental groups and their members, attacking the Bush administration EPA’s proposed 70 percent reduction in mercury emissions by 2018 as being far too lenient. A number of comments, by contrast, raised doubts that any further action regulating mercury is justified.

EPA puts the price of the proposed rule at more than $1 billion per year, and others think it could cost considerably more. “Clear Skies would reduce mercury emissions by 70 percent, [but] at a cost of about $4 billion per year,” noted American Enterprise Institute visiting scholar Joel Schwartz regarding a similar plan to cut mercury emissions by 70 percent, proposed by the Bush administration in 2003.

Comments on the EPA proposal raised questions regarding whether U.S. utilities are a logical target for mercury reductions. Combustion of coal from power plants, for example, releases traces of mercury into the air, but power plants are a relatively small contributor of mercury. Natural sources of mercury and manmade sources other than U.S. power plants account for most of the mercury in the environment, noted Schwartz.

Recent research indicates even a “complete elimination of mercury from coal-fired utilities would reduce mercury deposition in the U.S. by at most about 10 percent,” said Schwartz in comments submitted to the agency.

Current Mercury Levels No Danger

Mercury emissions are the subject of public health debate because some airborne mercury is deposited into bodies of water, where it is transformed into potentially dangerous methylmercury, which is taken up by fish. Of greatest concern is the potential effect on neurological development in children whose mothers ate substantial amounts of contaminated fish during pregnancy. The scientific research is decidedly mixed as to whether consumption of such fish is harmful.

The strongest scientific case for concern about mercury has been made by a 2004 study in the Faroe Islands. The study, conducted by researchers from the Harvard School of Public Health and institutions in Japan, Denmark, and the Faroe Islands, followed the progress of children born to mothers exposed to relatively high levels of methylmercury through whale meat consumption during pregnancy. The study concluded there was a modest loss of neurological development in the children. “The implications for neurological and cognitive health are relatively minor,” noted Schwartz in his comments to EPA, even assuming Faroe Island results are indicative of harm to American children whose mothers ate fish during pregnancy.

A University of Rochester Medical Center study, conducted in the Republic of the Seychelles and published in May 2003, is probably more applicable to the United States. Unlike the Faroe Islands study, the residents of the Seychelles ate ocean fish similar to those consumed by Americans, rather than whale meat. In addition, whereas whale meat is also contaminated by polychlorinated biphenyls (PCBs), which may also cause health problems, there were no potential contaminants in the Seychelles fish other than methylmercury. The Seychelles study, which has tested the same group of children five times from the age of six months to nine years, has uncovered no evidence of developmental or other problems.

The Center for Science and Public Policy concluded in May 2004 that the Seychelles study found “no observable health effect associated with fish consumption in which methylmercury is present” and “the Faroe Islands study should not be the sentinel study upon which assessment of methylmercury intake via fish consumption should be gauged.” EPA, however, has chosen to rely on the Faroe Islands study rather than the Seychelles research.

Proposed Rules Have Questionable Legality

EPA itself has lent credence to concerns about the strength of its case for the proposed rule. The agency’s benefit analysis, released in June 2004, conceded it is “unable to model the impacts of the mercury … emissions reductions that may result from this regulation.” Instead, the agency assumes mercury controls will also reduce other power plant emissions, and it calculates the potential benefits based on declines of those emissions.

For that reason, the proposed mercury rule may be on shaky legal grounds. Under the Clean Air Act, EPA is to set power plant mercury standards only if the evidence shows they are “appropriate and necessary” based on evidence of a public health threat. The Utility Air Regulatory Group, which represents utilities affected by the proposed rule, stated in its comments, “EPA readily admits that it cannot quantify the linkage between mercury levels in humans and mercury emissions from coal-fired power plants.”

Hence, the group argues, “EPA’s conclusion that regulation of mercury emissions from coal-fired power plants is appropriate and necessary is not supported by the factual record.”

Though far outnumbered by comments urging aggressive action against power plant mercury, EPA’s docket also contains comments raising serious concerns whether any power plant emissions reductions are warranted. EPA is now obligated by administrative procedure law to address those concerns before moving forward with its proposed rule.


Ben Lieberman ([email protected]) is director of air quality policy and associate counsel at the Competitive Enterprise Institute (http://www.cei.org).