ConAgra, the largest microwave popcorn distributor announced that it would no longer add the flavor-enhancing chemical diacetyl to its Orville Redenbacher and Act II brands, based on claims that it may cause a deadly lung disease called bronciolitis obliterans. Recently a man claimed that he developed the ailment after eating microwave popcorn daily. Although a scientific correlation between digesting the chemical and developing the illness has yet to be proven, it has been linked to illness in factory workers.