Wednesday Sep 5 (Foodconsumer.org) -- A chemical known as diacetyl used in microwave popcorn butter flavor was thought early to affect the workers at popcorn plants only.   But a possible case in which a 53-year Colorado man has suffering a serious lung condition caused doctors suspected by long term exposure to microwave popcorn butter flavor suggests that this chemical may harm consumers as well.

Diacetyl is a key component used in butter flavor indicated for use in microwave popcorn.   The chemical with a vicinal diketone is very reactive and in the lungs can react with proteins, potentially damaging lung tissue and enzymes and disrupting normal physiology, a scientist affiliated with foodconsumer.org suggested.

The first bronchiolitis obliterans associated with exposure to diacetyl vapor was diagnosed in former workers of a microwave popcorn plant in Jasper, Missouri. This is a serious lung disease that is irreversible. Many workers filed lawsuit against their employer and won in many cases if not all.

In the Colorado case, the furniture businessman complained to his doctors that he was becoming increasingly short of breath.   He was diagnosed as hypersensitivity pneumonitis, an inflammation of the lungs, but doctors could not identify a single risk factor in the man such as smoking, exposure to bacteria, mold or dust. No doctors initially thought that the man’s lung disease was induced by diacetyl in popcorn butter flavor.

Dr. Cecile Rose, director of the occupational disease clinical programs at National Jewish Medical and Research Center in Denver happened to have consulted to flavorings manufacturers for many years about "popcorn workers' lung.   She found the man's condition was similar to those induced by diacetyl in the popcorn workers, according to The New York Times.

Dr. Rose asked the man if he ate lots of popcorn. He told her that he had been eating freshly microwaved popcorn twice a day for more than ten years.   Thus exposure to diacetyl became a prime suspect for the man’s lung disease and he was advised to stop eating popcorn.   As a result, his condition was getting improved.   Dr.   Rose reported the case in a recent letter to government agencies.

The flavoring industry insists that diacetyl is safe although the U.S. government has urged both the industry and consumers to avoid or minimize use of or exposure to the chemical.  But many popcorn manufacturers are considering changing their formulae to avoid use of this dangerous chemical that.