Monterey County Herald, "Danger for Popcorn Workers; Health Workers Try to Determine Extent of Illnesses"

          "We know that butter flavorings are very widely used," said Dr. Gregory Wagner, director of the National Institute for Occupational Safety and Health’s Division of Respiratory Disease Studies. "What we don't know is how much injury has occurred."
          NIOSH has documented cases of similar lung disease at four out of five other microwave popcorn plants it has investigated. Additional cases have been reported at three other popcorn factories and four manufacturers of butter flavoring. Recently, NIOSH has received scattered reports of problems in other facilities -- including a candymaker and a snack food plant -- but the agency has been unable to confirm those cases so far.
          NIOSH is charged with investigating reported workplace dangers. NIOSH met in the fall of 2001 with the American Popcorn Board and the Flavor and Extract Manufacturers Association, hoping to share information and to gain access to more plants. Some companies, such as family-owned B.K. Heuermann Inc. in Nebraska, welcomed NIOSH. But others were less cooperative.
          ConAgra Foods, Inc., for example, let NIOSH conduct air sampling at its popcorn plant in Hamburg, Iowa, in 2001, but the company would not allow workers to be interviewed or tested, NIOSH medical officer Dr. Richard Kanwal said.
          Later, ConAgra officials refused to let NIOSH visit its plant in Marion, Ohio, even after the agency learned in 2002 that a former worker had been diagnosed with bronchiolitis obliterans. Only after three employees signed a confidential request did investigators get to the scene.