Is microwave popcorn toxic?

Risks for Consumers of Microwave Popcorn
It's likely safe to consume microwave popcorn at home,
It's likely safe to consume microwave popcorn at home,
© Photographer: Cerlobea | Agency:

Dr. Cecile Rose, a lung specialist at the National Jewish Medical and Research Center in Denver, Colo., diagnosed the first case of popcorn lung in a consumer of microwave popcorn. That consumer, a man named Wayne Weston, claimed he made microwave popcorn at least twice a day for 10 to 12 years. He said that he loved the smell of buttered popcorn and would open the bag in front of his face and inhale the fumes. But over time Weston developed difficulty breathing and an incessant cough, which eventually landed him in the care of Dr. Rose, an expert on popcorn lung.

While Dr. Rose said that there's no definitive link between Watson's consumption of microwave popcorn and his illness, the connection appears strong. Tests of Watson's home revealed that when popcorn was being cooked, fume levels were comparable to those found in factories [source:]. It likely didn't help that Watson placed his face directly in the path of the diacetyl-laced steam billowing from popcorn bags and did so thousands of times.

In July 2007, Dr. Rose sent a letter about her findings to government health officials, who said they would look into the case. Dr. Rose's tests showed that Watson's symptoms were consistent with popcorn lung, and after he stopped eating buttered popcorn, his lung function improved. He was able to stop taking some of his medications. He also lost 50 pounds.

Eating microwave popcorn is not believed to be harmful. The danger comes from the fumes given off in the cooking process, and consistent exposure to those fumes may be dangerous. The Food and Drug Administration has said that diacetyl is safe to consume, but some consumer rights advocates say more studies need to be done. Proposed legislation in California would ban diacetyl, and a Congresswoman from Connecticut requested that the FDA ban diacetyl until its effects are better understood.

An impending report from the FDA, expected to be released in September 2007, will look at the gases produced when microwaving popcorn. The report should also reveal the quantity of diacetyl and other chemicals to which consumers may be exposed. But some observers complain that the study examines only the type and quantity of fumes produced by microwave popcorn and not their health effects.

The results of the study were released to popcorn makers in 2006, but the FDA said more time was required for peer review and revision before the study could be published in a scientific journal. The FDA claimed it allowed popcorn makers to examine the study to make sure no trade secrets were revealed, but some questioned the decision, with one scientist telling the Seattle Post-Intelligencer that the move was "questionable science at its worst" [source: Seattle Post-Intelligencer].

In the meantime, while factory workers should be concerned, it's probably safe to continue eating buttered popcorn -- just be careful around the fumes or look for a brand that doesn't use diacetyl. For the average popcorn lover, it shouldn't be a problem. The director of the Center for Science in the Public Interest told the Associated Press that the trans fats found in buttered popcorn were more dangerous to consumers than diacetyl [source:].

For more information about diacetyl, the potential dangers of microwave popcorn and other related topics, please check out the links below.

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More Great Links


  • "4 major popcorn makers to drop toxic chemical." Associated Press. Sept. 5, 2007.
  • "Popcorn-lung patient inhaled directly from bags." Associated Press. Sept. 6, 2007.
  • Emery, Chris. "ConAgra to drop popcorn flavoring." Baltimore Sun. Sept. 6, 2007.,0,5666138.story?coll=bal-pe-asection
  • Harris, Gardiner. "Doctor Links a Man's Illness to a Microwave Popcorn Habit." New York Times. Sept. 5, 2007.
  • Schneider, Andrew. "That buttery aroma might be toxic, too." Seattle Post-Intelligencer. Aug. 30, 2007.