WASHINGTON (AP) — The Senate narrowly confirmed a lawyer for the petrochemical industry on Thursday to a key post at the Environmental Protection Agency to oversee air pollution regulations affecting his former clients.

William Wehrum was approved on a vote of 49 to 47 to serve as assistant administrator for air and radiation. He previously served as a regulator at EPA under President George W. Bush.

Republican moderate Sen. Susan Collins of Maine joined Democrats in voting against President Donald Trump's nominee. Four senators, two from each party, did not vote.

Wehrum is expected to help administrator Scott Pruitt in an ongoing push to reverse or delay Obama-era regulations, including those seeking to decrease emissions from coal-fired power plants. Like Trump, Pruitt disputes the consensus of leading climate scientists that carbon emissions from burning fossil fuels is the primary cause of global warming.

As an attorney, Wehrum represented the interests in Washington of clients that included the American Petroleum Institute, American Fuel & Petrochemical Manufacturers, the American Chemistry Council and the National Association of Manufacturers.

Sen. John Barrasso, the Wyoming Republican who chairs the Senate environment committee that weighed Wehrum's nomination, praised his credentials.

"The EPA's air office has been responsible for creating the agency's most punishing regulations," Barrasso said. "Bill Wehrum's three decades of environmental policy experience will be enormously helpful as he works to cut red tape, protect America's air and allow our economy to grow."

Sen. Sheldon Whitehouse, a Rhode Island Democrat who serves on the environment committee, said Wehrum is the latest in a series of industry insiders and science deniers appointed to key regulatory jobs at EPA.

"It is an array of cranks, charlatans, hacks, lobbyists, toadies in really unprecedented measure in the history of our country," Whitehouse said in a speech on the Senate floor just before the vote. It seems that at this point the key and only credential for appointment to the Environmental Protection Agency is that you are reliably pro-industry and reliably anti-public health."

Environmentalists worried Thursday that Wehrum will help further weaken clean air protections already under assault by the Trump administration.

"It's genuinely hard to fathom someone less suited to lead clean air efforts at the EPA than Bill Wehrum," said Andrea Delgado, a legislative director at the environmental advocacy group Earthjustice. "Like other Trump nominees, he has made a career leading efforts to weaken standards that protect us from mercury, silica, lead and smog at the expense of the health and safety of children, workers and communities."

___

Follow AP Environmental Writer Michael Biesecker at http://twitter.com/mbieseck