[1] Soonchunhyang Univ, Coll Nat Sci, Asan, South Korea
[2] Seoul Natl Univ Hosp, Dept Internal Med, Seoul, South Korea
[3] Seoul Natl Univ, Sch Publ Hlth, Seoul, South Korea
[4] Seoul Natl Univ, Dept Nucl Med, Coll Med, Seoul, South Korea
[5] Univ Montana, Ctr Environm Hlth Sci, Dept Biomed & Pharmaceut Sci, Missoula, MT 59812 USA
[6] Natl Inst Environm Res, Environm Hlth Res Div, Minist Environm, Incheon, South Korea