Besides all the hardship the workers face at factories that make food flavorings, they are at additional risk of developing a rare and life-threatening lung disease called bronchiolitis obliterans. The hard-to-treat condition causes vague symptoms such as cough and shortness of breath, but steadily worsens. This lung disease is caused by exposure to noxious gases in occupational settings and has been described in workers in the microwave-popcorn industry who were exposed to artificial butter-flavoring chemicals. Because the manufacture of flavorings involves more than 2,000 chemicals, workers in the general flavor-manufacturing industry are exposed to more chemicals than workers in the microwave popcorn industry, which primarily uses butter flavorings.

According to the experts occupational Safety and Health Administration is not yet paying proper attention to the issue.
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