Asbestos and non-asbestos fiber content in lungs of Korean subjects with no known occupational asbestos exposure history

To provide an estimation of asbestos exposure among normal Koreans and a criterion for determining occupational asbestos exposed diseases, pulmonary fiber contents of both asbestos and non-asbestos types were evaluated in 20 Korean subjects with no known occupational history of asbestos exposure. Pulmonary fiber contents were analyzed by transmission electron microscopy with energy dispersive X-ray analysis after using the low temperature ashing procedure. Chrysotile fiber (65.5%) was the major fiber type found in the lungs of Korean subjects. Asbestos fiber concentrations found in males and females were 0.30×106fibers/g of dry lungs and 0.15×106fibers/g of dry lungs, respectively, showing a geometric mean concentration of 0.26×106fibers/g of dry lung tissue. Non-asbestos fiber contents found in males and females were 8.02×106fibers/g of dry lungs and 7.85×106fibers/g of dry lungs, respectively, with a geometric mean concentration of 7.98×106fibers/g of dry lungs. There was no difference in asbestos content in lungs among various age groups. Comparing these results with Japanese male (2.11×106fibers/g of dry lung) and female subjects (1.38×106fibers/g of dry lung), Korean male and female subjects had much less asbestos in their lungs.