New uses for certain chemicals now need US environmental regulators' sign-off

US environmental regulators are tightening rules for a specific group of chemicals. Companies must now get explicit approval from the agency before using these chemicals in new ways.

For a set of chemicals already under scrutiny, companies can no longer introduce them into new products or processes without a direct green light from the US environmental regulators. This means the agency gets a veto on how these substances are used, shifting the burden of proof for safety onto manufacturers for any novel application.