ConAgra has decided to drop diacetyl, a flavoring it adds to its microwave popcorn, as doctors have indicated there may be a raised risk of developing bronchiolitis obliterans, a type of lung disease. ConAgra is the largest microwave popcorn supplier in the world.

Recently, Dr. Celile Rose, Denver’s National Jewish Medical and Research Center, said she suspects she may have a patient who most likely developed bronchiolitis obliterans as a result of inhaling diacetyl when preparing and eating microwaved popcorn. Dr. Rose said there is no firm evidence that the patient got his rare lung disease from the popcorn – however, she stressed that there is no other explanation.

People who work in popcorn factories have been known to develop bronchiolitis obliterans.

What is Diacetyl?

Diacetyl is a natural byproduct of fermentation. It is known as a vicinal diketone – it has two C=O groups, side by side. It’s chemical formula is C4H602.

Diacetyl, at low level, gives beer or wine a slippery feel. At higher levels one can taste a butterscotch flavor.

Diacetyl gives popcorn its butter taste. The US National Institute for Occupational Safety and Health has long advised that when used as an artificial butter flavoring one should avoid inhaling it over a long period.

Bronchiolitis obliterans, an uncommon and serious lung disease, has been found in workers of several factories that produce artificial butter flavorings. Experts say that young, healthy, non-smoking male workers are the most susceptible.

In medical circles bronchiolitis obliterans is often termed “popcorn worker’s lung”. However, any worker who works with diacetyl has a higher risk of developing the disease, compared to the rest of the population.

A popcorn worker in Missouri, USA, was awarded $2.7 million in July 2005, as a result of developing bronchiolitis obliterans from inhaling diacetyl at work. There are two bills in the California Legislature to ban the use of diacetyl.

What is Bronchiolitis Obliterans?

It is a disease of the lungs. The bronchioles are plugged with granulation tissue. It is a rare and life-threatening disease. This disease must not be confused with BOOP (bronchiolitis obliterans organizing pneumonia), a completely different disorder of the lungs.

A patient with bronchiolitis obliterans may experience shortness of breath and have a dry cough, he/she may also be wheezing a lot. His/her lung capacity will be at about 16% to 21% lung usage, compared to a normal capacity of 80%.

There is no cure for this disease, apart from a lung transplant. Treatment is extremely limited.

ConAgra web site

Written by: Christian Nordqvist