http://www.jsonline.com/story/index.aspx?id=521615
The flavoring chemical diacetyl - used in many manufactured foods - has been tied to three deaths and serious illness in at least 200 people, yet it remains unregulated by the government and under the radar of doctors
Diacetyl attacks, inflames and virtually obliterates the bronchioles, the lung's tiniest airways. As the body tries to heal, scar tissue builds up and restricts the airways. The damage is irreversible, though it sometimes can be moderately controlled with medications. Rats exposed to diacetyl at levels similar to those in factories suffered major lung injuries, according to 2001 reports by the National Institute for Occupational Safety and Health. Half died within six hours.