Popcorn worker's lung: In vitro exposure to diacetyl, an ingredient in microwave popcorn butter flavoring, increases reactivity to methacholine

Introduction:
This text provides an in-depth analysis of a study investigating the effects of diacetyl, an ingredient in microwave popcorn butter flavoring, on airway reactivity in guinea pigs. The study aims to understand the potential mechanisms underlying the development of popcorn worker's lung, a condition that affects workers in the microwave popcorn industry.

Key Points:

* The study used an isolated, perfused trachea preparation to assess the effects of diacetyl on epithelial barrier function and airway reactivity to methacholine (MCh).
* Diacetyl exposure compromised epithelial barrier function, leading to hyperreactivity to mucosally applied MCh.
* Ussing chambers were used to examine the effects of diacetyl on the bioelectric properties of the epithelium, revealing that diacetyl degraded the barrier function of the epithelium.
* The study found that diacetyl itself, and the effect of diacetyl treatment on responses of the preparations to bronchoactive agents, led to hyperreactivity in vitro.
* The tracheal epithelium appeared to serve as an initial target for the toxic effects of diacetyl in the airways.
* The findings suggest that bronchiolitis obliterans, a progressive obstructive disease associated with lung transplantation, may also be triggered by adverse drug reactions or inhalation of airborne toxins, such as diacetyl.
* an outbreak of clinical bronchiolitis obliterans occurred in food industry workers inhaling microwave popcorn artificial butter flavoring, with high levels of diacetyl and other volatile flavorings detected in the work site air.

Main Message:
The study highlights the potential health risks associated with diacetyl exposure, particularly for workers in the microwave popcorn industry. The findings suggest that diacetyl can compromise epithelial barrier function, leading to hyperreactivity in the airways and potentially contributing to the development of popcorn worker's lung. Regulatory measures should be taken to minimize diacetyl exposure in the workplace and protect workers' health.

Fedan, J.S., J.a. Dowdy, K.B. Fedan, and a.F. hubbs. “Popcorn Worker’s Lung: In Vitro Exposure to Diacetyl, an Ingredient in Microwave Popcorn Butter Flavoring, Increases Reactivity to Methacholine.” Toxicology and applied Pharmacology 215, no. 1 (august 15, 2006): 17–22. https://doi.org/10.1016/j.taap.2006.02.001.