Harmful chemicals in sewage sludge spread on pasture as fertilizer pose a risk to people who regularly consume milk, beef and other products from those farms, in some cases raising cancer risk “several orders of magnitude” above what the Environmental Protection Agency considers acceptable, federal officials announced Tuesday.

Michael Regan, who has led the Environmental Protection Agency throughout President Joe Biden’s four-year term, said Friday he will be leaving the agency Dec. 31, about three weeks before Biden’ leaves office.