A priority for employers should be the implementation of safety measures to minimize worker exposure to flavoring chemicals, according to the Centers for Disease Control and Prevention (CDC) Morbidity and Mortality Weekly Report (MMWR).
Engineering controls, including local exhaust ventilation and closed transfer of chemicals, should be the primary control measures, according to CDC.
Other precautions should include work practices such as covering containers and minimizing spills.
Employers should also establish a comprehensive respiratory protection program for organic vapors and particulates that adheres to the Occupational Safety and Health Act (OSHA) Respiratory Protection Standard.
And consultation with an industrial hygienist or occupational safety and health professional might be necessary to implement appropriate engineering controls, work practices, and an appropriate respiratory protection program, said the report.
Diacetyl, an artificial butter flavoring used in popcorn, pastries, frozen foods and candies, has been repeatedly linked to lung disease in employees of popcorn plants.
However, there are currently no enforceable OSHA standards requiring exposures to be controlled.
And while unions push for the regulatory loophole to be addressed, employees in popcorn plants continue to be diagnosed with the rare - and often fatal - lung disease bronchiolitis obliterans, while flavor manufacturers continue to fork out settlement charges in cases brought against them.
The CDC report examines the first two cases of bronchiolitis obliterans, as well as the findings of a public health investigation, and the actions taken by state and federal agencies to prevent future cases.
Two cases of the disease were reported in 2004 and 2006 to the California Department of Health Services (CDHS) and Division of Occupational Safety and Health (Cal/OSHA).
In response to these reports, Cal/OSHA conducted enforcement investigations of the two flavor companies involved.
The firms were required to conduct spirometry screening and reduce employee exposure to diacetyl and other flavoring ingredients.
In April 2006, Cal/OSHA and CDHS implemented a cooperative intervention program to encourage the state's entire flavor-manufacturing industry to implement the same measures.
It identified 28 flavor firms in the state, all of which agreed to participate in the program, which required that they conduct medical surveillance of exposed workers, assess and control exposure to chemicals, and accept agency supervision of these activities.
CDC said the companies are currently in various stages of establishing their medical programs.
In addition, industrial hygienists from CDC's National Institute for Occupational Safety and Health (NIOSH) have assessed exposures and developed guidance on work practices and exposure-control technology for three companies.
"A better understanding of work-related risk factors for bronchiolitis obliterans in the flavoring industry will facilitate establishing priorities for preventive interventions.
Cal/OSHA and CDHS will aggregate data from the 28 companies to identify manufacturing processes and types and concentrations of flavoring chemicals associated with occupational lung disease," wrote the report.
In January last year, NIOSH recommended that employers take measures to limit employees' occupational respiratory exposures to food flavorings and flavoring ingredients in workplaces where flavorings are made or used'.
Reporting in the journal Chest, the team concluded that workers exposed to flavoring agents were nearly four times more likely to develop airway inflammation, a sign people were breathing in harmful agents.
The alert stemmed from a series of NIOSH health hazard evaluations that began in 2000 when NIOSH learned of the occurrence of bronchiolitis obliterans in workers at a microwave popcorn packaging plant.
Bronchiolitis obliterans has been identified in microwave-popcorn workers in several states, including Missouri, Iowa, Ohio, New Jersey, and Illinois.
The disease in flavor-manufacturing workers has been identified in Ohio, California, Maryland, and New Jersey.
Although the risk for occupational lung disease has been established in the microwave-popcorn industry and improvements have been made - such as isolating processes, increasing exhaust ventilation, and using respirators - the risk for occupational lung disease associated with the use of flavorings during production of other types of food has not been established.