Scientists ID Likely Culprit in 'Popcorn Lung'

(HealthDay News) -- A key chemical ingredient in the buttery flavoring of microwave popcorn has been identified as a likely culprit in "popcorn lung," a lung disease that afflicts people who work in the microwave popcorn manufacturing industry, Dutch researchers report.

Publishing in the September issue of the American Journal of Respiratory and Critical Care Medicine, the team said that the chemical diacetyl may be responsible for more cases of bronchiolitis obliterans syndrome (BOS), otherwise known as "popcorn lung," at a diacetyl factory.

"Our study found a cluster of [previously undiagnosed] BOS cases in a diacetyl production plant," lead author Dr. Frits van Rooy, of the Division of Environmental Epidemiology at the Universiteit Utrecht, said in a prepared statement. "This supports the conclusion that an agent in the diacetyl production process has caused BOS."

The disease was first noticed in 2001 among workers at an American plant that made microwaveable popcorn. Diacetyl was identified early on as an indicator of exposure, but the chemical's role in the development of the lung disease was not known.

The research team in the Netherlands traced 196 former workers who were still alive and had been employed at the diacetyl production plant between 1960 and 2003. They identified 175 who agreed to fill out exposure and respiratory health questionnaires. The workers also took lung function tests and completed clinical assessments. Four cases of "popcorn lung" were identified in the 102 workers thought to be at risk for high exposure.

The authors noted that this was the first study of lung health among workers for a plant producing diacetyl. They acknowledged that they could not rule out the impact of other chemicals made at the same plant, but the data created a stronger case for diacetyl as a possible cause of "popcorn lung." Acetoin and acetyldehyde may also contribute, the researchers said.

An editorial accompanying the journal article expressed concern over the fact that none of the four cases had been diagnosed as an occupationally related lung disease or bronchiolitis obliterans specifically prior to the study.

More information
To learn more about bronchiolitis obliterans, visit Haz-Map: Occupational Exposure to Hazardous Agents.