Occupational exposure to crystalline silica (quartz) and prevalence of lung diseases in Dhand Killi, Mohmand Agency, northern Pakistan
Abstract
Occupational exposure to respirable crystalline silica (quartz) has long been known to produce fatal lung diseases specifically silicosis and pulmonary tuberculosis. To address this, issue a cohort analysis of occupational exposure, relation to crystalline silica (quartz), the mortality and morbidity rate of various lung diseases were carried out among silica miners and millers in Dhand Killi Mohmand Agency, northern Pakistan. The exposure level of respirable silica (quartz) in the indoor environment counts from 1-14 mg/m3 per 1 hour, which is thousand fold higher as compared to internationally recommended exposure limits (0.05 mg/m3) over time weighted average of 8 hours. The mortality and morbidity rate of silica related lung diseases were found potentially high among the silica (quartz) miners and millers during the follow up period (1996 to 2004) in the target area. The overall analytical data illustrates that the cohort cases of occupational exposure to respirable silica (quartz) and silica related fatal diseases is remarkably high.
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