Bronchiolitis obliterans may be caused by inhalation of airborne diacetyl, a chemical used to produce the artificial butter flavoring[17] in many foods such as candy and microwave popcorn and occurring naturally in wines. This first came to public attention when eight former employees of the Gilster-Mary Lee popcorn plant in Jasper, Missouri, developed bronchiolitis obliterans. In 2000, the Missouri Department of Health called in the National Institute for Occupational Safety and Health to make a determination of the cause, and to recommend safety measures. After surveying the plant and each patient's medical history, NIOSH recommended respiratory protection for all workers in microwave popcorn production. Due to this event, bronchiolitis obliterans began to be referred to in the popular media as "popcorn lung" or "popcorn workers lung".[18][19][20][21] It is also referred to as "flavorings-related lung disease".[22] Bronchiolitis obliterans caused by diacetyl inhalation begins with a cough, wheezing and dyspnea (shortness of breath), and usually progresses slowly, but severe symptoms can develop without warning. Other symptoms that appear in some workers include fever, weight loss, and night sweats. Symptoms do not change when workers are away from the workplace.[22] CT images show bronchial wall thickening and trapped air. Non-smokers may be at higher risk for this form of bronchiolitis obliterans. The Occupational Safety and Health Administration (OSHA) recommended that diacetyl manufacturing companies regularly sample air in work environments, provide air purifying respirators, and engage in medical surveillance of at-risk workers. In 2011, National Institute for Occupational Safety and Health proposed a recommended short-term exposure limit of 25 parts per billion (ppb) and a time weighted average exposure of 5 ppb.[21] In 2007 a heavy consumer of microwaved popcorn was diagnosed by a doctor in Denver with "popcorn lung," the first known case involving a consumer.[23] On 16 January 2008, it was announced that Wayne Watson, a Denver man who developed "popcorn lung" after inhaling fumes from microwaved popcorn, was suing the Kroger grocery store chain and its affiliates. In the lawsuit, filed in U.S. District Court, Watson's attorney claimed that the companies "failed to warn that preparing microwave popcorn in a microwave oven as intended and smelling the buttery aroma could expose the consumer to an inhalation hazard and a risk of lung injury."[24] On 19 September 2012 a jury in U.S. District Court in Denver awarded $2.3 million in actual damages and $5 million in punitive damages to Watson. Defendants included Gilster-Mary Lee, the manufacturer; Kroger, and Kroger's subsidiary Dillons, owners of King Soopers & City Market, a Colorado regional supermarket chain.[25][26][27] okay but ngl don't judge me but i like LIGHT stuffing. yeah that kind On 27 August 2007, Weaver Popcorn Company of Indianapolis promised to replace the diacetyl butter flavor ingredient in Pop Weaver popcorn with another flavoring.[28] In September 2007, Dr. Cecile Rose, pulmonary specialist at Denver's National Jewish Health medical and research Center, warned federal agencies that consumers, not just flavoring or food factory workers, may be in danger of contracting bronchiolitis obliterans. David Michaels, of the George Washington University School of Public Health, first published Rose's warning letter on his blog.[29][30] On 4 September 2007, the Flavor and Extract Manufacturers recommended reduction of diacetyl in butter-like flavorings. The next day ConAgra Foods announced that it would soon remove diacetyl from its popcorn products.[31] Diacetyl is approved by the Food and Drug Administration as a safe flavor ingredient, but there is evidence to suggest that inhalation in large amounts is dangerous. There are currently no warnings from federal regulators about diacetyl. Diacetyl is found in the vapor created by some electronic cigarette flavours.[32] A NIOSH peer-reviewed publication documents that, in laboratory studies, acute inhalation exposures to acetyl propionyl(2,3-pentanedione), one of the compounds with a buttery flavor and/or smell put forward as a safer alternative to diacetyl, cause airway epithelial damage that is as harmful as diacetyl.[33]