Hypersensitivity studies in popple (Aspen tree) peelers.

In the course of investigation of the relationship between hypersensitivity pneumonitis and the wood industry 45 popple peelers were studied. Four roentgenograms consistent with diffuse lung disease were found. All cases were in examinees who were also dairy farmers. Questionnaires revealed no instance of clinical symptoms of hypersensitivity pneumonitis. Gel immunodiffusion studies were positive to various antigens in eight cases, but no correlation could be made with pulmonary function or chest roentgenogram abnormalities in relation to occupation. Cultures of the wood and the surrounding environment yielded thermophilic fungi as well as other known antigenic material. It is concluded that the occupation of popple peeling does not represent an increased risk of development of hypersensitivity pneumonitis.