Methacholine bronchial responsiveness and variations in lung function among workers exposed to flour.

Objectives: Methacholine bronchial responsiveness and variations in the pulmonary function of workers exposed to wheat flour and a reference group were compared.

Methods: Each subject [140 men exposed to flour (bakers and pastry makers) and 77 controls] completed a standardized questionnaire. Bronchial responsiveness was quantified by measuring the slope between percentage decrements in forced expiratory volume in 1 second (FEV1) and cumulative methacholine dose.