Biographical note of the first author: Wen-Jie ZHANG, female, born in 1979, Ph.D. candidate for both Beijing Normal University and institute for Environmental Health and Related Products Safety, China CDC. Majoring in atmospheric aerosol and related environmental health problems. Correspondence should be addressed to Dong-Qun xu (E-mail: dongqunxu@yahoo,com,cn) Correspondence should be addressed to Guo-Shun ZHUANG (E-maih gzhuang@bnu.edu,cn).