Senator Kennedy introduced the No IRIS Act of 2025, which would prevent the Environmental Protection Agency (EPA) from using assessments produced by its Integrated Risk Information System (IRIS) program in developing new regulations, enforcing existing rules, or making permitting decisions. The bill would also prohibit the EPA from using IRIS assessments in air toxics evaluations or other mapping and screening tools. This legislation would affect anyone subject to EPA regulations, as it would limit the scientific basis the agency can use to establish environmental and health standards. The bill contains no specific funding provisions or implementation timelines, but would immediately restrict the EPA's ability to rely on this particular data source in its regulatory work once enacted.