The National Academy of Sciences (NAS) says the Environmental Protection Agency (EPA) was using correct science in setting tight standards for mercury exposure to protect at-risk groups, namely children of women who consumed large amounts of fish during pregnancy.

The EPA is currently discussing new regulations for controlling emissions from the main sources of mercury exposure: coal-fired utility boilers, which release around 40 tons of mercury annually in the United States.

Proponents for capping mercury emissions hailed the NAS findings, claiming they cleared the way for new controls.

"Mercury is the last major toxic substance without an emissions control plan. The report brings us to the goal line, and Congress needs to act in the public's interest and to stop doing the bidding of the special interests," said Sen. Patrick Leahy, a Democrat from Vermont.

The NAS report was issued as part of an 18-month review of the EPA mercury standards. The science group said the EPA's current "reference dose" for methylmercury, a common mercury compound, of 0.1 micrograms per kilogram of body weight per day, was justified.

In the past, mercury poisoning has resulted in

• mental retardation
• cerebral palsy
• deafness and blindness

The NAS concludes that mercury pollution is sufficient to result in an increase in the number of children who have to struggle to keep up in school and who might require remedial classes or special education.

NAS said the long-term goal of programs to reduce mercury exposure should be aimed at reducing the amount of mercury in fish and seafood, and not by telling pregnant women to cut down on fish consumption, which is generally beneficial to people.

"The science is in. Mercury is highly toxic. The federal government needs to stop the delaying tactics and reduce human exposures to mercury," said Michael Bender, executive director of the Mercury Project.