The U.S. Environmental Protection Agency announced on Tuesday it will bar certain scientists from serving on its independent advisory boards, a move critics say could open the way to more industry-friendly advisers on the panels.

The EPA barred scientists who have won agency-awarded grants in the past, billing the step as a way to preserve the independence and diversity of the boards, which provide the scientific input for agency decisions around pollution and climate change regulation.

"Whatever science comes out of EPA, (it) shouldn't be political science," EPA Administrator Scott Pruitt said in a release, adding that committee members will be "financially independent" from the agency.