Silica Exposure and Effect on Peak Expiratory Flow: Slate Pencil Workers' Study.

BACKGROUND: Peak expiratory flow (PEF) is a spirometric test that detects obstructive changes in the respiratory tract; has good correlation with the FEV1; and is much less expensive, simpler, and easier to perform under field conditions than FEV1. Chronic silicosis is also known to have obstructive features in advanced stages. Thus, this study was performed to assess the effect of silica exposure on PEF and the factors related to it.

METHODS: The present study was carried out among 193 slate pencil cutting workers of Multanpura village of Madhya Pradesh, India. An interview technique was used to record demographic characteristics and occupational history on a predesigned form, which included a questionnaire regarding occupational history and silica-related respiratory morbidities. This was followed by a complete medical examination and measurement of PEF using a spirometer.

RESULTS: The mean age was 43.35 ± 11.31 y, and the mean duration of exposure was 18.72 ± 9.33 y. In the present study, PEF was found to be significantly reduced in those age ≥40 y, those who were female, those having duration of exposure >10 y, and those having respiratory morbidity, whereas the reduction in PEF was statistically nonsignificant for smokers.

CONCLUSIONS: Higher age, female sex, higher duration of exposure, and respiratory morbidity were found to be important correlates of PEF.