Asbestos in the ambient air from rural, urban, residential, baseball and mining areas in South Korea

摘要

Asbestos is a naturally occurring fibrous silicate that has been widely used as electrical insulator and heat-resistant material in buildings, yet inhalation of asbestos fibers can lead to serious lung diseases such as asbestosis and cancer. Practically no research has been conducted on the size distribution and morphological characteristics of airborne asbestos, and airborne asbestos concentrations in South Korea are unknown. Here we studied type, concentration, size, morphology and composition of asbestos fibers in the ambient air of several regions in South Korea. Asbestos concentrations were analyzed in 7 urban areas, 7 rural areas including agricultural and fishing areas, 17 mines and their surrounding areas, 7 residential areas constructed with asbestos-containing stones near rivers, 2 baseball fields and 2 background sites. Results show that the highest air asbestos concentrations were 0.00161 for residential areas and 0.00122 for baseball fields according to phase-contrast microscopy, and 0.00057 for asbestos mines and 0.00055 for baseball fields, according to transmission electron microscopy. Asbestos types included chrysotile, tremolite, and actinolite. Chrysotile fibers measured 5.24-35.5 mu m in length with aspect ratios of 12.6-202.6; tremolite fibers measured 6.07-40.2 mu m in length with aspect ratios of 5.7-81.2; and actinolite fibers measured 5.01-28.5 mu m in length with aspect ratios of 3.2-108.9. Chrysotile was distributed in bundles or single fibers, whereas tremolite and actinolite exhibited fibrous, acicular, and cleavage forms.