Washington (CNN) Embattled EPA Administrator Scott Pruitt proposed a new rule Tuesday that he said will make the Environmental Protection Agency more "transparent."

His announcement, however, was made only to invited guests.

The proposal would allow the agency to use only scientific studies where the underlying data is publicly available. Pruitt said the change would expand the ability of scientists and the public to "comment on the veracity, the authenticity" of data behind EPA decisions.

But environmental groups say the public disclosure requirement will limit the EPA's access to health studies, which are subject to patient confidentiality requirements. The plan would blacklist air quality studies that have linked pollution and health issues, for example, they argue.

"They are ordering EPA employees to put on blinders and only see the science that they want them to see," said Andrew Rosenberg of the Union of Concerned Scientists.

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