EPA terminates 40-year IRIS chemical risk program by deputy administrator memo

EPA Deputy Administrator David Fotouhi issued a memo on April 27, 2026, formally ending the Integrated Risk Information System, the 40-year-old program that provided peer-reviewed health assessments for more than 500 toxic chemicals used by regulators nationwide. The memo directed that IRIS findings would no longer carry regulatory weight and that individual program offices would conduct their own chemical assessments going forward. Chemical industry groups including the National Association of Manufacturers had lobbied for years to eliminate IRIS, calling its assessments overly conservative.