Why are dentists dying of a lung disease?

Why are dentists dying of a lung disease?  Yahoo News Dentists keep dying of this deadly lung disease. The CDC can't figure out why  Philly.com Dentists keep dying from a rare lung disease, but no one knows why  NOLA.com Idiopathic Pulmonary Fibrosis | the lung association  The Lung Association Dentists Mysteriously Dying of Lung Disease: CDC Report  NewsweekFull coverage

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