Pulmonary Impairment and Risk Assessment in a Diacetyl-Exposed Population

Abstract

Objectives: The butter flavoring additive, diacetyl (DA), can cause bronchiolitis obliterans (BO) by inhalation. A risk assessment was performed using data from a microwave popcorn manufacturing plant. Methods: Current employees’ medical history and pulmonary function tests together with air sampling over a 2.7-year period were used to analyze forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (FVC). The exposure responses for declining pulmonary function and for possible early onset of BO were estimated using multiple regression methods. Several exposure metrics were investigated; benchmark dose and excess lifetime risk of impairment were calculated. Results: Forty-six percent of the population had less than 6 months exposure to DA. Percent-of-predicted FEV1 declined with cumulative exposure (0.40 per ppm-yr, P < 10−7) as did percent FEV1/FVC (0.13 per ppm-yr, P = 0.0004). Lifetime respiratory impairment prevalence of one per thousand resulted from 0.005 ppm DA and one per thousand lifetime incidence of impairment was predicted for 0.002 ppm DA. Conclusion: DA exposures, often exceeding 1 ppm in the past, place workers at high risk of pulmonary impairment.

Electronic nicotine delivery system design and aerosol toxicants: A systematic review

“…A handful of chemical agents used in the flavoring of e-liquid have been specifically investigated. Diacetyl and acetyl propionyl, which produce buttery or creamy flavors, have received attention for associations with bronchiolitis obliterans (i.e., "popcorn lung") among microwave popcorn industry workers [117,118] and have been investigated in e-liquid flavoring [82,92]. Cinnamaldehyde has been observed to be cytotoxic [103].…”

Current intelligence bulletin 69: NIOSH practices in occupational risk assessment.

“…Ideally, adequate MoA information would be available to support the decision on risk characterization without equivocation; however, in practice this is rarely the case. Instead, a decision against PoD/ UF usually follows careful consideration of the nature and severity of the adverse effect, its observed association with the agent of interest, and the Park et al 2002;Park and Gilbert 2018]. An illustration is NIOSH's recently completed assessment of the risks from diacetyl exposure in the workplace [NIOSH 2016].…”

Increased chemical acetylation of peptides and proteins in rats after daily ingestion of diacetyl analyzed by Nano-LC-MS/MS

“…Diacetyl is a flavoring commonly used in foodstuffs, as it lends a buttery flavor to products such as popcorn, coffee blends, cakes, cookies, wines and other goods ( McCoy et al, 2017 ; Shibamoto, 2014 ; Ryan et al, 2014 ; Papetti, Mascherpa & Gazzani, 2014 ; Park, Gilbert & Whittaker, 2018 ; More, Raza & Vince, 2012 ). It is a volatile α-dicarbonyl and a highly electrophilic compound ( Ryan et al, 2014 ) approved worldwide for use by food industries, despite ongoing health concerns dating back to 1986 ( NIOSH, 1986 ), when the first cases of bronquiolitis obliterans involving diacetyl emerged ( Park, Gilbert & Whittaker, 2018 ; Kreiss, 2014 ; Kanwal et al, 2011 ).…”