INDIANAPOLIS (AP) - Weaver Popcorn Co., one of the nation's top microwave popcorn makers, has switched to a new butter flavoring, replacing a chemical linked to a lung ailment in popcorn plant workers.

The Indianapolis-based company began shipping new butter-flavored microwave popcorn a few weeks ago that contain no diacetyl, a chemical undergoing national scrutiny because of cases of bronchiolitis obliterans, a rare life-threatening disease often called popcorn lung.

Company President Mike Weaver said that while his workers have experienced no such cases, the family owned business wanted to lead the popcorn industry and allay consumer fears by eliminating the chemical for its product line.

``There's a growing awareness and concern among consumers about diacetyl and as that is talked about or reported on consumers listen, and our concern was how does that effect how they look at this product?'' he said Wednesday. ``We felt this was the prudent thing to do.''

Weaver said his company sells about 600 million bags of microwave popcorn a year, giving it about a 20 percent share of the U.S. market.

Concerns about diacetyl have been growing for years as have the number of lawsuits filed by workers suffering from the progressive lung disease, which can force sufferers to undergo lung transplants.

Several flavor manufacturers are either researching alternatives to diacetyl or are already marketing butter flavors free of the chemical, said John Hallagan, general counsel for the Flavor and Extract Manufacturers Association, based in Washington, D.C.

He said there's no evidence that eating products containing diacetyl can be harmful. The concern instead focuses on workers inhaling it in manufacturing settings - either in making the flavoring or adding it to food products ranging from popcorn to pound cakes.

Weaver Popcorn is the first popcorn manufacturer to replace diacetyl with another butter flavoring, said David Michaels, associate chairman of George Washington University's Department of Environmental and Occupational Health.

He said breathing even low levels of diacetyl can be dangerous.

``It's a very dangerous chemical. We know there are people who are sick in factories where they make diacetyl and where they apply the flavors,'' he said. ``There are cases not just in popcorn factories but at least one potato chip factory.''

The federal Occupational Safety and Health Administration has been looking at the use of diacetyl in manufacturing settings, particularly popcorn plants, for about two years, said Deirdre Flynn, executive director of the Popcorn Board, a Chicago-based industry group.

Legislation before California lawmakers would ban the chemical's use in that state. And U.S. Rep. Rosa L. DeLauro, D-Conn., asked the U.S. Food and Drug Administration in May to ban the flavoring chemical until it can be thoroughly studied.

08/29/07 19:32 © Copyright The Associated Press. All rights reserved. The information contained In this news report may not be published, broadcast or otherwise distributed without the prior written authority of The Associated Press.