Researchers Tracing Chemical Cause of 'Popcorn Worker's Lung'
The Sept. 1 online issue of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society, probes the occupational lung disease at a Missouri microwave popcorn flavoring plant producing diacetyl in 2001, which triggered a NIOSH investigation and has prompted congressional appropriations committees to insert language in OSHA's FY2008 funding bill directing quick work on a protective standard. Dutch researchers identified a chemical agent that may be a culprit in bronchiolitis obliterans syndrome (BOS), or "popcorn worker's lung," according to the journal. There is no PEL or IDLH established for diacetyl; science groups and unions also have called for a standard governing exposures to it.
"Our study found a cluster of [previously undiagnosed] BOS cases in a diacetyl production plant," said lead author Frits G. B. G. J. van Rooy, M.D., of the Division of Environmental Epidemiology at the Universiteit Utrecht. "This supports the conclusion that an agent in the diacetyl production process has caused BOS." BOS had not previously been identified in workers at chemical plants producing flavorings. Dr. van Rooy and colleagues obtained pulmonary tests and questionnaires from 175 of the 196 former workers who were still living and worked at the plant between 1960 and 2003, when it closed. They identified 102 process workers at highest risk for exposure, finding among them four cases of BOS.
"The spectrum of exposures is much smaller in this production plant compared with the popcorn processing plants where a wide range of chemicals was identified," the researchers wrote in the article. "This population-based survey establishes the presence of BOS, or popcorn worker's lung, in chemical workers manufacturing a flavoring ingredient with exposures to diacetyl, acetoin, and acetyldehyde. Any or all of these exposures may contribute to the risk of this emerging occupational disease." To contact Dr. van Rooy, write to Institute for Risk Assessment Sciences, Division Environmental Epidemiology, Universiteit Utrecht, P.O. Box 80178, 3508 TD, Utrecht, Netherlands, phone +31 30 253 9494, or e-mail [email protected]