EPA is proposing to tighten regulation of fluoropolymers that could break down into toxic perfluoroalkyl carboxylates, such as perfluorooctanoic acid and perfluoroalkyl sulfonates, including perfluorooctanyl sulfonate (PFOS). The action would affect an estimated 120 fluorochemicals used to impart stain and soil protection, resistance to oil and water, and reduced flammability on various consumer products. Since 1995, EPA has allowed chemical companies to produce new fluoropolymers without submitting premanufacture notices to the agency for review. Under a rule proposed on March 7, the agency would eliminate this exemption and require premanufacture notices for existing and future production of specific kinds of fluoropolymers. The proposal affects polymers that contain perfluoroalkyl sulfonates, such as the PFOS-based ingredients that 3M phased out of its Scotchgard products; perfluoroalkyl carboxylates; fluorotelomers, which are fluorinated alcohols; and perfluoroalkyl moieties that are covalently bound to either a carbon or a sulfur atom. EPA said it proposed the change because some fluoropolymers may degrade and release perfluoroalkyl sulfonates or perfluoroalkyl carboxylates. These substances are expected to bioaccumulate and persist in the environment and are likely to be "highly toxic," the agency said.