Lead, Mercury, and Cadmium Exposure in the Korean General Population

Background: Lead (Pb), mercury (Hg), and cadmium (Cd) are well-known environmental pollutants. They are unnecessary in the biological processes of humans. This study was performed to estimate the representative background exposure levels to the metals by measuring concentrations in whole blood of the Korean general population. Methods: This population-based cross-sectional study included 4,000 subjects (1,886 males and 2,114 females) 0-83 years of age in 2010 and 2011. Adult subjects (>= 19 years of age) were collected by sex-and age-stratified probability method, and preschool-and school-aged subjects were recruited by a cluster sampling method. Written consent was provided prior to blood sampling. Pb and Cd blood concentrations were determined by a flameless atomic absorption spectrophotometry, and blood Hg was analyzed by a direct Hg analyzer. Results: The geometric mean, median and 95th percentile of blood Pb was 1.82 mu g/dL, 1.83 mu g/dL, and 3.78 mu g/dL, respectively. The respective values were 2.92 mu g/L, 2.87 mu g/L, 9.12 mu g/L for Hg, and 0.56 mu g/L, 0.59 mu g/L, 2.20 mu g/L for Cd. Blood Pb and Hg were higher in males than in females, but no sex difference was observed, respectively, in subjects 0-4 years of age for Pb and in subjects less than 20 years for Hg. However, blood Cd was higher in females than in males and no sex difference was observed in subjects < 30 years of age. Conclusion: This study provides representative data of human exposure to Pb, Hg, and Cd covering whole age groups of the general population in Korea.