WASHINGTON — The Obama administration on Wednesday revealed a long-delayed regulation to curb emissions of ozone, which causes smog and has been linked to asthma and other respiratory problems.
Business groups panned the Environmental Protection Agency’s regulation as unnecessary and the costliest in history, warning they could jeopardize a resurgence in American manufacturing. But EPA Administrator Gina McCarthy argued that the public health benefits far outweigh the costs and that most parts of the country can meet the tougher standards without doing anything new.
‘‘We need to be smart — as we always have — in trying to find the best benefits in a way that will continue to grow the economy,’’ McCarthy said. Of reducing ozone, she added: ‘‘We’ve done it before, and we’re on track to do it again.’’
Ozone joins a long list of pollutants that Obama has wanted to limit using EPA regulations, seeking to cement an environmental legacy by sidestepping Congress and its opposition to new pollution laws.
After pledging during his first presidential campaign to tighten ozone limits, Obama backtracked in 2011 by yanking the EPA’s proposed ozone limits amid pressure from industry. Obama said it was important to cut regulatory red tape while the economy was recovering.
The latest proposed regulation would lower the current threshold for ozone pollution to a range of 65 to 70 parts per billion, from 75 parts per billion. Environmental groups sought a stiffer standard of 60 parts per billion. The EPA proposal would seek public comment on the more stringent threshold, keeping open the possibility the final rule could be stricter.
The agency estimates that the new regulation would by 2025 prevent 320,000 to 960,000 asthma attacks in children. It also estimates that by 2025 the rule would prevent 750 to 4,300 premature deaths.
The regulation would come with a high cost to industry, which the EPA estimates would be $3.9 billion in 2025, using a standard of 70 parts per billion. The cost would be $15 billion in 2025 at a standard of 65 parts per billion. (The EPA chose 2025 because that is when the agency expects the regulation to be fully in force.)
The agency estimates that the economic benefits of the rule — measured in avoided asthma attacks, heart attacks, missed school and work days, and premature deaths — would significantly outweigh the costs. It calculates the benefits at $6.4 billion to $13 billion annually in 2025 for a standard of 70 parts per billion and $19 billion to $38 billion annually for a rule of 65 parts per billion.
Next year, the EPA is expected to make final two more historic Clean Air Act rules aimed at cutting planet-warming greenhouse gas emissions from coal-fired power plants. Those rules, which are intended to curb pollutants that contribute to climate change, could lead to the shutdown of hundreds of power plants and freeze construction of future coal plants.
The Republican-majority Congress, to be led by Senator Mitch McConnell of Kentucky, the incoming majority leader, has vowed to block or overturn the entire group of rules.
In a separate development, the Supreme Court on Tuesday agreed to take up a challenge to another EPA rule intended to curb emissions of mercury.
“We’re facing a series of regulations, and the cumulative cost of compliance and the burden of permitting is significant,” said Cal Dooley, president of the American Chemistry Council, which has lobbied aggressively against the rules.
The standard for ozone was last set in 2008 by the Bush administration at a level of 75 parts per billion, above the range of 60 to 70 parts per billion recommended by the EPA’s scientific advisory panel at the time. Environmental and public health groups challenged the Bush standard in court, saying it would endanger human health and had been tainted by political interference.
The EPA plans to give states that have the most ozone up to 2037 to come into compliance. But McCarthy said most of the United States won’t have to take any action, thanks to existing EPA limits on mercury and carbon dioxide that also reduce ozone.
Material from the Associated Press was used in this report.