CONCORD, N.H. – The attorneys general of New England and New York are fighting federal efforts to relax emission controls for older power plants, citing a new study of nitrogen pollution in northeastern forests and lakes.

“The damage documented in the study includes diminished forest productivity of up to 14 percent from nitrogen-induced ozone,” reads the letter sent Tuesday to EPA Administrator Christie Whitman.

It was signed by the attorneys general of Maine, New Hampshire, Connecticut, Massachusetts, Rhode Island and New York.

In addition, harmful levels of acidity can be found in more than 30 percent of Adirondack lakes and at least 10 percent of New England’s lakes, according to the study. Earlier research suggests the figures are as high as 41 percent for Adirondack lakes and 15 percent for New England lakes.

“This new evidence highlights the need for dramatic reductions in nitrogen oxide emissions from electric utilities located upwind from our states,” the letter continues.

Dave Deegan, a spokesman for the Environmental Protection Agency, said Tuesday he wasn’t familiar with the study and that no one was immediately available to comment on it.

The study from the Hubbard Brook Research Foundation in New Hampshire was published in the journal BioScience last week and involved the work of a dozen scientists.

The scientists concluded that aggressive reductions in nitrogen pollution from power plants, motor vehicles and agricultural runoff provide the best hope of addressing these problems.

“The study also concludes that atmospheric levels of nitrogen have remained constant in the northeast since the 1960s, despite recent amendments to the [Clean Air] Act and that the most recent amendments to the Act will not reduce emissions enough to prevent continuing damage to our natural resources,” the letter to Whitman said.

Among other things, the study calculated future nitrate levels and acid-neutralizing capacities in the waters of Hubbard Brook Experimental Forest in New Hampshire and Biscuit Brook in the Catskills in the year 2030 and 2050 under different public policy approaches.

The attorneys general are using this and other evidence as part of a continuing challenge to the EPA’s changes to regulations. These regulations date to 1977 and affect the way older industrial plants are required to deal with air pollution when they expand, make major repairs or modify operations to increase efficiency.

The Bush administration issued rules last year making it easier for industrial plants and refineries to modernize without having to buy expensive pollution controls, and it is still seeking changes in rules for aging coal-burning power plants.