By Valerie Volcovici
WASHINGTON (Reuters) - A multimedia, multi-state advertising blitz from industry groups opposing new national ozone standards reached Pennsylvania on Tuesday, part of their last-ditch attempt to scuttle the Obama administration's plans to issue new rules governing ground-level smog by Oct. 1.
"Now Washington is trying to force through new rules that will stifle our economy and kill millions of jobs," the ad says.
The U.S. Environmental Protection Agency sent its recommendations for tighter ozone levels to the White House last week. The agency has called for lowering concentrations of ozone to between 65 and 70 parts per billion from the current level of 75 ppb.
There is a strong consensus among health groups for the toughest ozone standard possible, said Paul Billings, senior vice president for advocacy at the American Lung Association.
"The science supporting it is only stronger today," Billings said.
But the fossil fuel industry and its allies say the existing limit introduced under President George W. Bush in 2008 is strict enough to protect public health.
Since July, their ads on TV, in newspapers and on websites have tried to build opposition to new ozone regulations in electoral swing states such as Colorado and Ohio. They will target Virginia and New Mexico in coming weeks
They say lowering the permissible level of ozone would impose a greater burden on industry than any EPA regulation ever passed, citing a study commissioned by the National Association of Manufacturers last year that put the cost of compliance at $270 billion annually.
Industry critics also say the new rule would shift goalposts on states that are set to meet the Bush-era standard.
"Many of these states have spent the last two to three decades aggressively working to improve their air quality," said Matt Dempsey of the Center for Regulatory Solutions, a lobby group that opposes what it calls over-regulation.
Industry representatives say their campaign has struck a chord with some unions and African-American groups, which fear the tougher standard could lead to job losses.
Environmentalists and public health groups say they plan to fight back through social media and education campaigns in September by touting the health benefits, such as reduced childhood asthma rates, of lowering ozone levels.
Environmentalists accuse industry groups running a fear-mongering campaign, saying the manufacturing group's report touted "hyper-inflated costs" based on unrealistic scenarios.
"Industry simply stopped talking about the science and they never talk about the law," which requires updates to the standards reflect scientific demands, said John Walke of the Natural Resources Defense Council.
Industry groups say the ads are already having an impact in Colorado. On Monday, Democratic Governor John Hickenlooper said he was not yet convinced stricter standards are needed.
Last week Democratic Senator Michael Bennet he was "deeply concerned" about the EPA proposal, which "does not make sense on the ground."
Bennet, who is up for re-election in 2016, later said through a spokesman that he would support an EPA ozone rule giving Colorado flexibility on how it is implemented.
(Reporting by Valerie Volcovici; Editing by Bruce Wallace and Lisa Von Ahn)