Democrats, scientists and environmental groups denounced the decision. They said E.P.A. advisory boards already had stringent conflict of interest policies, and they asserted that neither Mr. Pruitt nor Republican critics of the panels had found any cases in which academic advisers profited from the agency by providing advice.
“The really galling part of this is that it’s all in an effort to avoid conflict of interest, but they pretend that the industry people who are being offered up positions on the panel are somehow unbiased because they’re not getting money from E.P.A.,” said Donna Kenski, director of data analysis at the Lake Michigan Air Directors Consortium in Illinois. Ms. Kenski, who was dismissed from the Clean Air Scientific Advisory Committee on Tuesday, said her organization received money from E.P.A. indirectly through the State of Illinois.
“I don’t believe it’s really about the funding,” Ms. Kenski said. “I believe it’s a blatant attempt to politicize a process that has been refreshingly free of politics.”
Mr. Pruitt is expected to ask about two dozen people to replace advisers whose terms have ended or were removed under the new rules, according to a list provided by several people close to the process. Among the expected appointees, several are state regulators and private consultants; one is a senior director at the American Chemistry Council, a trade association; another is the chief environmental officer for Southern Company, an electric utility; and one is the vice president of technology for Phillips 66 Research Center in Oklahoma, and previously worked for ConocoPhillips.
The E.P.A. did not confirm the full list of new appointees, but did announce that Michael E. Honeycutt, the top toxicologist at the Texas Commission on Environmental Quality, would chair the E.P.A.’s Scientific Advisory Board. Dr. Honeycutt has sparred with the E.P.A. over ozone standards, and was a co-author of a study in an air and waste management magazine arguing that the agency has inflated the health benefits of more stringent air quality standards.
Senator Benjamin L. Cardin, Democrat of Maryland, called Mr. Pruitt’s directive unprecedented and dangerous.
“This administration’s attack on science is clear when the E.P.A. administrator replaces members of its federal advisory committees, many of whom are leaders in their respective fields, with individuals tied to industry and state officials known to be critical of E.P.A.’s authority to protect human health and the environment,” Mr. Cardin said in a statement.
Mr. Pruitt said researchers would have to choose between receiving grants or serving on E.P.A. committees.
“Choose this day whom you will serve,” he said, quoting a Bible verse. “Either service on the committee to provide counsel to us in an independent fashion or choose the grant. But you can’t do both.”