Occupational asthma due to tea dust.

Three patients are described who had developed asthma after working as tea packers. In two cases the diagnosis was confirmed by serial monitoring of peak expiratory flow rates, bronchial responsiveness to histamine, and specific inhalation challenges in the laboratory. The third patient experienced isolated changes in bronchial responsiveness to histamine after periods of exposure at work and after specific inhalation challenges in the laboratory without showing spirometric changes. Two of the three subjects were non-atopic; none had an immediate reaction to skin prick testing with a tea solution.