O-122 Determinants of task-based exposures to alpha-diketones in coffee roasting and packaging facilities

Introduction Coffee production is a global industry and is estimated to increase by 15.4 million lbs in 2021. Coffee production workers can be exposed to inhalational hazards such as diacetyl and 2,3-pentanedione, which are associated with the development of occupational respiratory disease, including obliterative bronchiolitis, a rare and irreversible lung disease. Objective Identify determinants contributing to task-based exposures to alpha-diketones, specifically diacetyl and 2,3-pentanedione, at 17 U.S. coffee roasting and packaging facilities. Methods We collected 606 personal task samples including roasting (n=189), grinding (n=74), packaging (n=203), quality control (n=44), flavoring (n=15), and miscellaneous production/café (n=81). Samples were collected and analyzed according to the modified OSHA Method 1013/1016. Information on sample-level and process-level factors relating to production scale, sources of alpha-diketones, and engineering controls was collected during surveys. Bayesian mixed-effect regression models accounting for censored data were fit for overall data and specific tasks including roasting, grinding, packaging, quality control, and flavoring. Significant determinants were used in multiple regression models using variable selection or model averaging Bayesian methods. Results Task-based sample durations ranged from 2–86 minutes. Total number of alpha-diketone sources, sum of all open storage sources, average roasted coffee production per day, average percent of production as ground coffee, flavoring during survey, and number of grinders all resulted in increased exposures for at least one task category. General exhaust ventilation (GEV) with natural ventilation, supply air turned on, and GEV turned on resulted in lowered exposures for at least one task category. Conclusions GEV and supply air turned on and natural ventilation were identified in most models as determinants which reduced exposures. Open storage of roasted coffee and flavoring during survey were significant in most models contributing to higher task exposures and can be targeted for exposure mitigation to reduce short-term and full-shift exposures and minimize risks for respiratory disease.