The subjects were divided into two groups. Group I had
107 subjects who had been working in a highly polluted area
(Total suspended particles matter (T5P) more than 0.33 rng/m3
/24 hours) and group IT, 103 subjects, who had worked in a low
polluted area.(T5P less than 0.33 mg/m3/24 hours) (Table 1).2
After the subjects completed the questionnaires
concerning personal histories, medical histories and work
activities, they were randomly selected to perform either the vital
capacity or chest expansion test. The tests were made with the
subject in the standing position. The measurement of the vital
capacity, recording the maximal expired volume after a deep
inspiration, was made on a Buhl model spirometer Chest
69
expansion, recording the difference between the maximal girth
at the xiphoid level after a deep inspiration and after a full
expiration, was measured by a tape.4
Three sets of tests of, vital capacity and chest expansion,
were performed with a rest between breaths and the highest
readings were selected for analysis. Using unpaired Student's
t-test and a value of p