The White House and Environmental Protection Agency intervened earlier this year to block the publication of a federal health study revealing potentially hazardous levels of toxic chemicals in drinking water to avoid a “public-relations nightmare,” Politico reports, citing newly disclosed internal emails. The study, by the Health and Human Services’ Agency for Toxic Substances and Disease Registry (ATSDR), concerned a water-contamination crisis near military bases and chemical plants in several U.S. states. With one of the key findings showing that chemicals in the water supply are more hazardous to humans than the EPA has previously disclosed, White House aides reportedly moved quickly to keep the report under wraps. “The public, media, and congressional reaction to these numbers is going to be huge,” one unidentified aide was quoted as saying, also warning of “extremely painful” blowback against the EPA and Defense Department. “We cannot seem to get ATSDR to realize the potential public-relations nightmare this is going to be,” the aide wrote. The Health and Human Services Department confirmed to Politico on Monday that the study remains unpublished, with no release date scheduled.