US environmental regulators can now block new chemicals before they hit the market

The US environmental regulators are updating rules for 17 specific chemicals. Companies must now tell the agency 90 days before they plan to make or use these chemicals in new ways. The agency can then review the proposed use and block it if it finds problems.

For decades, new chemicals could enter the market with little oversight. The US environmental regulators often had to prove a chemical was harmful after it was already in use. This change means the agency can stop a chemical before it is widely deployed, shifting the burden of proof to manufacturers for these specific substances. It gives the agency a proactive tool to manage chemical risks, rather than just reacting to problems.