A 53-year-old Colorado man who ate two bags of microwaved popcorn daily for 10 years apparently developed bronchiolitis obliterans—“popcorn worker’s lung,” a debilitating disease previously seen only among workers at popcorn factories. Medical researchers suspect that inhaled diacetyl, the chemical that gives microwave popcorn its sinful buttery flavor, gradually inflames and scars the lungs’ tiny air sacs, making it increasingly difficult for sufferers to exhale.
Cecile Rose, a physician who specializes in the disorder at the National Jewish Medical and Research Center in Denver, alerted the U.S. Food and Drug Administration in July that her coughing patient’s Colorado home had diacetyl levels similar to those in factories. But the news only became public in September on a health policy blog that accused regulators of ignoring the potential risk to popcorn lovers. Four major popcorn manufacturers quickly announced they would phase out diacetyl.