Workers of three cotton spinneries, with different amounts of cotton dust in the athmosphere of work places, were studied according to the epidemiological method of study proposed by Schilling, as compared with 135 workers not exposed to cotton dust. Through the answers to the international questionnaire on lung diseases, it was disclosed that workers from mills with highest concentration of cotton dust in the air presented symptoms characteristic of byssinosis; on the other hand, lung function tests performed on mondays immediately after the period of work showed impairment of lung function when compared with tests performed immediately before starting work. As in the control group lung function tests actually became better after the period of work, it is supposed that the non-existence of changes in lung function after work in mills the amount of cotton dust in the air was low-may be an indication of an early impairment of lung function due to the inhalation of cotton dust.
Dust; Pneumoconiosis; Respiratory tract infections
