The use of diacetyl (2,3-butanedione) and related flavoring substances as flavorings added to foods-Workplace safety issues.

In 2001, staff of the National Institute of Occupational Safety and Health (NIOSH) identified diacetyl (2,3-butanedione) as a "marker" of exposure in a microwave popcorn manufacturing facility in which workers developed severe respiratory illness. Subsequent investigations identified additional workers in food and flavor manufacturing facilities also with severe respiratory illness. The flavor industry, NIOSH, and federal and state regulators conducted significant programs to address workplace safety concerns related to the manufacture of flavors and foods containing added flavors. These programs, initiated in 2001, continue today. Key to the success of these programs is understanding what flavors added to foods are and how they are manufactured, how they are incorporated into foods, the specific characteristics of diacetyl and related flavoring substances, and what actions may be taken to assure the safest workplaces possible.