Acting EPA Administrator Andrew Wheeler has appointed five new members of an independent committee that provides advice to the EPA on national air quality standards, replacing the current members, while reducing the amount of support it gets from other scientists, according to an agency statement and emails obtained by CNN.

Wheeler’s appointments mean that the Clean Air Scientific Advisory Committee’s (CASAC) entire membership has been replaced over the course of the year.

The changes have left some scientists concerned that the committee will not be able to properly advise the EPA on its policies and procedures regarding national air quality standards.

“Protecting the public’s health from dangerous amounts of pollutants in the air that we all breathe is the mandate of this agency,” Jack Harkema, a professor of pathobiology and diagnostic investigation at Michigan State University and now-former member of the committee, told CNN. “This cannot be done without careful, deliberate and knowledgeable understanding of this complex environmental health issue. Multidisciplinary teams of scientific experts must be free to conduct thorough peer-review of the pertinent science. Millions of lives are at stake.”

During an interview with CBS’s “60 Minutes” on Sunday, President Donald Trump expressed skepticism that climate change was a man-made problem, stating “I think something’s happening. Something’s changing … I think there’s probably a difference. But I don’t know that it’s man-made.”

When pressed about scientists who have said climate change is worse than ever, Trump said, “You’d have to show me the scientists because they have a very big political agenda.”

But scientists are concerned that recent actions taken by the EPA will lessen scientific oversight of the agency’s policies.

Under the Clean Air Act, the EPA sets national ambient air quality standards for pollutants considered harmful to public health and the environment. Those standards were updated in 2015, and the EPA is working towards setting new ones by 2020, according to the agency.

The committee provides advice to the EPA on certain aspects of that effort, including how to set standards that protect public health with “an adequate margin of safety” and the possible negative impacts of agency strategies to meet those standards, an EPA press release announcing the appointments to the committee states.

While five new members were appointed to the committee this week, two were named earlier this year, according to Lianne Sheppard, a professor of biostatistics and environmental and occupational health sciences at the University of Washington who until recently was a committee member.

Scientists recently serving on the committee told CNN that they learned they would not be reappointed when Wheeler announced the committee’s five new members on Wednesday.

Sheppard said she had been on the advisory committee for one three-year term, but it was common practice for the agency to appoint members to two terms.

“A lot of us do this because we want to serve the public health, and we want to use our expertise to do that,” Sheppard said. “The EPA has dismissed us. It doesn’t want our input.”

Support panels ended

Wheeler has tasked the committee with leading the scientific review for any changes to the standards for ozone or particulate matter as well, according to the EPA release.

A day after Wheeler dismissed scientists on the committee and announced its five new members, the particulate matter panel, which supports the committee’s work, was disbanded, according to emails obtained by CNN from a source familiar with the matter. The emails also show that another panel on ozone would not be created at all.

The emails point directly back to the EPA’s press release about the committee’s new members and its being tasked with the review of changes to ozone and particulate matter standards.

The particulate matter panel was made up of about 20 scientists, according to Sheppard.

Former committee member Harkema expressed concern over the EPA’s decision to eliminate the supporting panels.

“The big concern is the dismantling of the ad hoc scientific panels for the review of the health effects of criteria ambient air pollutants like ozone and particulate matter,” Harkema said. “This is very dangerous because these are the scientific experts who work hard at unbiasedly reviewing the health-based findings.”

The Union of Concerned Scientists, an independent advocacy group, also expressed concern with the EPA’s decision to remove what they called “qualified, independent experts” from the seven-member committee and for disbanding the particulate matter panel.

“The fix is in,” Gretchen Goldman, research director of the Center for Science and Democracy at the Union of Concerned Scientists, said in a statement. “Every action taken by current EPA political leadership has been aimed at pushing independent science out of the process so they can gut the rules that protect the public from pollution. They’ve stacked the advisory boards, proposed restrictions on what science the EPA can consider, and limited the voice of independent scientists. They are determined to weaken safeguards that protect us from hazardous air pollution, regardless of the evidence. The consequences are enormous, and this represents a fundamental betrayal of the mission of the agency and the laws the EPA is supposed to enforce.”

When asked why the agency decided to disband the panels, EPA spokesperson John Konkus used some of the same language from Wheeler’s announcement.

“Consistent with the Clean Air Act and CASAC’s charter, Acting Administrator Wheeler tasked the seven-member chartered CASAC to serve as the body to review key science assessments for the ongoing review of the particulate matter and ozone National Ambient Air Quality Standards (NAAQS),” Konkus said.