Inhalation of a chemical used in microwave popcorn artificial butter flavoring damaged the airways of mice, which developed a condition that can lead to a life-threatening lung disease, says a study by researchers at the U.S. National Institute of Environmental Health Sciences (NIEHS).
Mice exposed to diacetyl vapors for three months developed lymphocytic bronchiolitis, a precursor to obliterative bronchiolitis (popcorn lung). None of the mice developed the more serious disease, said ConsumerReports.org.
"This is one of the first studies to evaluate the respiratory toxicity of diacetyl at levels relevant to human health. Mice were exposed to diacetyl at concentrations and durations comparable to what may be inhaled at some microwave popcorn packaging plants," study co-author Daniel L. Morgan, chief of the Respiratory Toxicology Group at the NIEHS, said in a prepared statement.
He and his colleagues concluded that workplace exposure to diacetyl contributes to the development of obliterative bronchiolitis, but noted that more research was needed. The study was published online in the journal Toxicological Sciences.
Obliterative bronchiolitis has been noted in microwave popcorn packaging plant workers who have inhaled significant concentrations of artificial butter flavoring. Late last year, a number of leading popcorn makers said they planned to eliminate diacetyl from their products, ConsumerReports.org said.