Fibrogenic and carcinogenic characteristics of asbestos occurring in Mohmand Agency, northern Pakistan
Abstract
This study has been carried out to identify the fibrogenic and carcinogenic characteristics including the type, physical dimension, and the fiber dose over time-weighted averages (TWA) of asbestos fibers mined, milled and used in Mohmand Agency. Fifteen representative rock and air samples of respirable Particulates matter (0.45-10µm) collected from various mines and milling units were analyzed using X-Ray Diffraction (XRD), Polarized Light Microscope (PLM) and Scanning Electron Microscope (SEM). The types of asbestos were classified as chrysotile, tremolite and anthophyllite. The concentration of asbestos fibers identified in respirable particulates (PM10, 7,5,3,2 and <2µm) were higher than the permissible limit (0.01f/cc per 8 hours) in the indoor environment. Majority of the fibers were found < 0.3 µm in width/diameter and > 8 µm long and indicate that the type of asbestos fibers released during mining and milling in Mohmand Agency is potentially carcinogenic.
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Exhibition organised by Bahrain Society of Engineers, Bahrain Center for Studies and Research, Arabian Gulf University and Ministry of Housing and Agriculture Bahrain, 267-280.
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