Peak expiratory flow and respiratory morbidity: a study among silica-exposed workers in India.

Background: The present cross-sectional study was carried out among 136 quartz stone grinders with the objective of studying the peak expiratory flow (PEF) and the associated epidemiological factors.

Methods: Interview technique was used to record demographic characteristics and occupational history on a predesigned proforma, which included questionnaires regarding demographic, occupational and clinical characteristics. This was followed by complete medical examination and measurement of PEF using Spirovit SP-10. The study included 75 (55.1%) male and 61 (44.9%) female silica-exposed workers. The mean age of the subjects was 31.77 +/- 9.99 years whereas the mean duration of exposure was 2.74 +/- 1.65 years. The mean PEF was found to be 5.16 +/- 2.1 L/min.

Results: In the present study the PEF was significantly reduced in those having respiratory morbidity on both unadjusted and adjusted analyses.

Conclusions: This suggests that along with the restrictive pathology caused by free silica dust, obstructive changes are also encountered in silica-exposed workers.