By David Michaels
The outbreak of severe lung disease caused by exposure to diacetyl, the chemical that makes food taste like artificial butter flavor, is growing. According to the California Department of Health Services, there are now eight known cases of severe obstructive lung disease among workers exposed to diacetyl, with three more reported cases under investigation.
How many cases are occurring in other states? No one knows, because California is the only state in the country that is actively collecting information. What’s striking about the California cases is that none of the workers are employed in microwave popcorn plants, the factories where the first cases of diacetyl-caused lung disease were identified. (The identification of the first cases of bronchiolitis obliterans at these factories is the reason the disease was given the now out-dated label “popcorn workers’ lung.”)
The food industry is a national one – food factories around the country use the same chemicals that are making workers sick in California. It has been almost six months since a group of unions and scientists petitioned OSHA for an emergency rule to protect workers from diacetyl.
OSHA has yet to take any action in response (this remains a case study in regulatory failure). The states, especially those with their own OSHA plans, can act on their own. Perhaps state epidemiologists in the other 49 will read the description of the known cases in California, compiled by Barbara Materna, PhD, CIH, Chief, Occupational Health Branch, California Department of Health Services, and begin to gather comparable information that could lead to state action to protect food indsutry workers. Here’s a portion of the California report:
These eight workers are 29 to 49 years old. They all live in Southern California, where the majority of flavor manufacturing plants are located. Six are male, and two are female. All are Latino, and half are known to prefer to be interviewed in Spanish. Of the six for which smoking history is known, none have ever been smokers. Only one worker is known to have had asthma as a child; the majority did not have asthma or other breathing problems before working in this industry.
The workers were or are currently employed at five different flavor manufacturing companies in Southern California. Seven workers for whom a job history is available have all worked in jobs that involve mixing chemicals, including diacetyl, to make food flavorings (flavor compounding). Some of the workers only made powder flavorings, while others made both liquid and powder flavorings. Of the eight workers, only one is still working at the same company, but has been moved to a job that does not involve diacetyl exposure.
The time reported between beginning work in flavoring manufacture and first experiencing symptoms such as cough, wheezing, or shortness of breath varies between one month and several years for these workers (this information is available on six workers). Some of the workers were initially treated for asthma, bronchitis, or allergic rhinitis; however, their conditions continued to deteriorate. Early on in some of these cases, an association with workplace exposure does not seem to have been considered.
Spirometry testing results (available for seven of the workers) show a Forced Expiratory Volume in one second (FEV1) ranging from 18 to 44% of what is normally predicted based on age, race, gender, height, and weight. FEV1 shows the volume of air that can be forced out of the lungs on exhalation in one second. A reduced FEV1 is one indicator of obstruction in the lung that makes it more difficult to exhale. Further testing is indicated to determine the likely cause of the abnormality.
Most of these workers are severely impaired, cannot work, and suffer extreme shortness of breath on exertion (for example, they can only walk a very short distance). At least one is reported to be on a list for lung transplantation.
David Michaels heads the Project on Scientific Knowledge and Public Policy (SKAPP) and is Professor and Associate Chairman in the Department of Environmental and Occupational Health, the George Washington University School of Public Health and Health Services.