Correcting Diacetyl Concentrations from Air Samples Collected with NIOSH Method 2557
- 10 January 2011
- journal article
- research article
- Published by Informa UK Limited in Journal of Occupational and Environmental Hygiene
- Vol. 8 (2), 59-70
- https://doi.org/10.1080/15459624.2011.540168
Abstract
Diacetyl (2,3-butanedione), a diketone chemical used to impart a buttery taste in many flavoring mixtures, has been associated with bronchiolitis obliterans in several industrial settings. For workplace evaluations in 2000–2006, National Institute for Occupational Safety and Health (NIOSH) investigators used NIOSH Method 2557, a sampling and analytical method for airborne diacetyl utilizing carbon molecular sieve sorbent tubes. The method was subsequently suspected to progressively underestimate diacetyl concentrations with increasing sampling site humidity. Since underestimation of worker exposure may lead to overestimation of respiratory health risk in quantitative exposure-effect analyses, correction of the diacetyl concentrations previously reported with Method 2557 is essential. We studied the effects of humidity and sample storage duration on recovery of diacetyl from experimental air samples taken from a dynamically generated controlled test atmosphere that allowed control of diacetyl concentration, temperature, relative humidity, sampling duration, and sampling flow rate. Samples were analyzed with Method 2557, and results were compared with theoretical test atmosphere diacetyl concentration. After fitting nonlinear models to the experimental data, we found that absolute humidity, diacetyl concentration, and days of sample storage prior to extraction affected diacetyl recovery as did sampling flow rate to a much smaller extent. We derived a mathematical correction procedure to more accurately estimate historical workplace diacetyl concentration based on laboratory-reported concentrations of diacetyl using Method 2557, and sample site temperature and relative humidity (to calculate absolute humidity), as well as days of sample storage prior to extraction in the laboratory. With this correction procedure, quantitative risk assessment for diacetyl can proceed using corrected exposure levels for air samples previously collected and analyzed using NIOSH Method 2557 for airborne diacetyl.Keywords
This publication has 7 references indexed in Scilit:
- Analytical Performance CriteriaJournal of Occupational and Environmental Hygiene, 2008
- Bronchiolitis obliterans in workers exposed to flavoring chemicalsCurrent Opinion in Pulmonary Medicine, 2008
- Respiratory Toxicologic Pathology of Inhaled Diacetyl in Sprague-Dawley RatsToxicologic Pathology, 2008
- Bronchiolitis Obliterans Syndrome in Chemical Workers Producing Diacetyl for Food FlavoringsAmerican Journal of Respiratory and Critical Care Medicine, 2007
- Method Development for the Determination of Diacetyl and Acetoin at a Microwave Popcorn PlantEnvironmental Science & Technology, 2003
- Clinical Bronchiolitis Obliterans in Workers at a Microwave-Popcorn PlantNew England Journal of Medicine, 2002
- The Computation of Equivalent Potential TemperatureMonthly Weather Review, 1980