WASHINGTON (AP) — The nation’s farms no longer have to report to authorities the toxic, smelly fumes released from manure.

The Bush administration issued a regulation Friday exempting farms from reporting releases of hazardous air pollution from animal waste to federal, state and local authorities. The rule applies specifically to the gases from manure that are often responsible for odor problems.

Environmental Protection Agency officials said that the changes will allow responders to focus on spills and releases from factories, natural disasters and other emergencies that require urgent attention. They said it would also reduce reporting burdens on America’s farmers, saying it is difficult to estimate the pollution coming from “a herd of cows.”

“When there is a train wreck, we need to know about it because we need to go out and look at chemical spills,” said Barry Breen, director of the agency’s Office of Solid Waste and Emergency Response. “When there is a lagoon full of manure there is nothing our folks can do when they show up.”

The farm reporting rule is one of several eleventh-hour environmental regulations unveiled by the Bush administration this week that were lobbied for by industry. The Interior Department on Thursday issued revised rules loosening protections for endangered species. And the EPA, also on Friday, issued regulations exempting industrial solvents and other chemicals that can be burned for fuel from the strict regulations governing hazardous waste.

Environmentalists lashed out again, saying that the new reporting rule would make it difficult to keep track of farms polluting the environment and putting neighbors at risk.

The gases released when animal waste decomposes include hydrogen sulfide, with its characteristic rotten egg smell, and ammonia. Exposure to these chemicals can cause respiratory problems and irritate the eyes, nose and throat.

“The effect of this is to create a loophole for all operations for not report their toxic emissions to the federal government,” said Ed Hopkins of the Sierra Club. “If you don’t know there is a problem you aren’t going to get a solution.”

Representatives of the poultry and beef industries said Friday the rule was long overdue. In 2005, associations representing chicken, turkey and egg farmers asked the Bush administration to exempt all ammonia emissions from reporting requirements.

The rule finalized Friday covers gases just from animal waste. Large farms with hundreds of dairy cows or thousands of pigs would still be required to report air releases to local and state authorities.

“We have always felt that reporting requirements … were never meant to address the release of naturally occurring substances,” said the National Chicken Council, National Turkey Federation and U.S. Poultry & Egg Association in a statement. “We believe the EPA heard our concerns and has come to a reasonable compromise.”

Congress also wanted clarification. In appropriations bills passed in 2005 and 2006, it directed the EPA to revisit the regulations.

Sen. Tom Harkin, D-Iowa, who chairs the Agriculture Committee, said that the EPA “needed to formulate a common-sense answer which recognizes that animal production is not the same as a chemical factory.”

But he criticized the Bush administration for pushing out the rule before a two-year, $14 million study launched last year on toxic air pollution from farms was finished.

The timing of the rule “almost guarantees that the issue will be revisited by the new administration and Congress,” Harkin said.