New Recommendations to Monitor Coffee Roasters for Potential Lung Disease
Bronchiolitis obliterans is commonly referred to as “popcorn lung” because several popcorn factory workers died when they developed the disease after occupational exposure to alpha-diketones from the butter flavoring. However, popcorn processors are not the only factory workers at risk to be exposed to hazardous levels of alpha-diketones at work. Exposure to hazardous levels of airborne alpha-diketones can lead to bronchiolitis obliterans. Patients with bronchiolitis obliterans have scarring in their bronchioles and suffer irreversible symptoms such as shortness of breath, dry coughing, and wheezing. Preventing environmental exposure to airborne alpha-diketones is crucial because, the symptoms of bronchiolitis obliterans can be quite severe—even fatal—many patients who develop severe bronchiolitis obliterans require a lung transplant.
The National Institute for Occupation Safety and Health (NIOSH) released official recommendations, including recommended exposure limits (REL), to control workplace exposure to alpha-diketones, particularly diacetyl and 2,3-pentanedione, chemicals commonly contained in food flavoring. NIOSH recommends individuals limit exposure during an eight hour work day during a forty-hour work week to diacetyl to 5 parts per billion (ppb). NIOSH also recommends that individuals limit short term exposure to diacetyl to 35 ppb for a fifteen-minute period. Similarly, NIOSH recommends that individuals limit exposure to 2,3-pentanedione to 9.3 ppb for an eight hour work day as part of a forty hour work week and limit short term exposure to 31 ppb during a fifteen-minute period. NIOSH Director John Howard stressed the importance of RELs stating that “We know these flavoring compounds can pose a great risk for workers who may be exposed on the job, causing serious and irreversible damage to their lungs.” NIOSH recommends that employers take corrective action when employees are exposed to 2.6 ppb of diacetyl to ensure that levels of diacetyl stay below the REL.
NIOSH organizes the Health Hazard Evaluation Program to help determine what health hazards are present in the workplace and establish recommendations to mitigate those hazards. As part of this initiative, NIOSH and the Centers for Disease Control (CDC) and United States Department of Health and Human Services (DHS) evaluated a coffee roasting and packaging facility in regard to concerns about exposure to diacetyl and 2,3-pentanedione.
The study evaluated employees’ exposure to the alpha-diketones during coffee processing, manufacturing tasks, and other factors as they relate to employee’s respiratory and systemic symptoms. Evaluators “designed the sampling strategy to assess full-shift exposures and to identify tasks and processes that were the greatest contributors to worker exposure to alpha-diketones.” Researchers took air samples during two sets of visits to the coffee processing facility, the first was a two day visit in July 2015, and the second was a two day visit in March 2016. Ultimately, ten of the forty-nine full-shift samples exceeded the NIOSH exposure limit of 5 ppb for diacetyl—one sample contained a maximum concentration of 8.4 ppb. Researchers noted that during their March 2016 visit, the processing plant had a slightly positive pressure which could lead contaminate air to flow from the production sites to office space. The study revealed that certain tasks emitted higher concentrations of diacetyl such as grinding, hand-blending, weighing, and packaging roasted coffee beans. The most commonly reported symptoms among study participants were mucous membrane symptoms such as eye, nasal, and sinus symptoms. Wheezing was the most commonly reported lower respiratory symptom— participants showed a fourfold excess of wheezing compared to the U.S. population of the same demographics.
In light of their recent evaluation, NIOSH, the CDC, and DHS, promulgated new recommendations to help coffee roasting and packaging plants monitor and prevent hazardous levels of alpha-diketones, particularly diacetyl, 2,3-pentanedione. The recommendations encompass engineering controls such as operating large exhaust fans in conjunction with an make-up air unit in production areas and opening bay doors; administrative controls, such as removing chaff from roasters and using an agitator instead of blending the coffee beans by hand; changes in personal protective equipment, such as utilizing respiratory protection; increasing medical monitoring for employees who work in the production area; and implementing a smoking cessation program. The full recommendations can be found here.
Health and safety in the work place should always be a top priority. Maintaining a safe work place includes preventing employee exposure to hazardous chemical compounds.
If you, a family member, or friend work in a food processing facility and have been diagnosed with bronchiolitis obliterans, we encourage you to contact us to help determine if workplace exposure to hazardous levels of airborne alpha-diketones caused your injury.