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Identification of diacetyl substitutes at a microwave popcorn production plant.
J Occup Environ Hyg 2012 Feb; 9(2):D33-D34
Diacetyl (2,3-butanedione) is a volatile diketone commercially synthesized and used to make butter flavoring for food production. It also is a naturally occurring product of fermentation and is found in butter, wine, and coffee. Diacetyl was first recognized as a respiratory health hazard at a microwave popcorn production plant.(1-3) The inhalation of butter flavorings containing diacetyl can cause severe shortness of breath and cough in workers exposed during microwave popcorn manufacturing. These symptoms may result from a rare, disabling lung disease called bronchiolitis obliterans, which has caused death or the need for lung transplant in some exposed microwave popcorn workers. Bronchiolitis obliterans has also been identified in flavoring and diacetyl manufacturing workers.(4,5) Accordingly, flavor manufacturers have started to substitute other chemicals for diacetyl in butter flavorings, including chemically similar diketones. One substitute, 2,3-pentanedione, in initial toxicity testing was comparable to diacetyl in causing epithelial injury.(6,7) Most other substitutes have not been tested in animals for airway damage. Food manufacturers may be unaware of the diacetyl substitutes being used in artificial butter flavorings purchased from flavoring producers, as in a recent investigation of a dry bakery mix plant.(8) A microwave popcorn production plant asked NIOSH to evaluate chemical constituents in their eight butter flavorings. Their flavoring supplier informed them that substitutes for diacetyl were being used in the formulations, but they were not told what these chemical substitutes were. NIOSH collected the liquid bulk butter flavoring samples at the plant and conducted a quantitative gas chromatography/mass spectrometry (GC/MS) analysis and a semi-quantitative headspace analysis using a thermal desorption tube technique on the samples. Companies need to be aware that the substitute diketones used in the butter flavors are unlikely to be safer than diacetyl.
Respiratory-system-disorders; Pulmonary-system-disorders; Lung-disorders; Ketones; Food; Foodstuff; Food-additives; Food-colors; Food-processing; Food-processing-workers; Toxic-materials; Chemical-analysis; Chemical-synthesis; Breathing; Airway-resistance
Randy Boylstein, National Institute for Occupational Safety and Health, Field Studies Branch, 1095 Willowdale Road, Morgantown, WV 26505
431-03-8; 600-14-6; 513-86-0; 3848-24-6
Issue of Publication
Journal of Occupational and Environmental Hygiene
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division