The U.S. Department of Labor's Occupational Safety and Health Administration
OSHA released a Safety and Health Information Bulletin on health hazards posed
to workers by occupational exposure to certain chemicals used to add flavor and
aroma to food and other products. Occupational Exposure to Flavoring
Substances: Health Effects and Hazard Control explains that the food flavoring
diacetyl, as well as some diacetyl substitutes, can burn the eyes, cause
soreness in the nose and throat, and irritate the skin and produce a severe
lung disease that has disabled or killed workers. Known initially as "popcorn
lung," the disease was first described among workers exposed to the flavoring
compound diacetyl, which is used in the production of low-fat, butter-flavored
popcorn. However, recent laboratory studies demonstrated that work environments
where chemicals are used as substitutes for diacetyl, such as flavoring
manufacturing plants and plants where flavors are added to snack foods, baked
goods, and candy, may also harm airways in animals. If workers exposed to
diacetyl or substitute chemicals experience symptoms including persistent cough
and shortness of breath, they are advised to ask their employers to send them
to a doctor for evaluation.

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AplusA-online.de - Source: U.S. Department of Labor's Occupational Safety and Health Administration