Chemicals

• A Study Is Retracted, Renewing Concerns About the Weedkiller Roundup - Problems with a 25-year-old landmark paper on the safety of Roundup’s active ingredient, glyphosate, have led to calls for the E.P.A. to reassess the widely used chemical.
• Starting With Formaldehyde, Trump Administration Reassesses Chemical Risks - A draft memo from the E.P.A. assumes a safe threshold exists for formaldehyde, upending earlier findings that there is no safe level of exposure to the carcinogen.