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Lead and Cadmium Levels in the Atmosphere in Mainland China: A review

Lead and Cadmium Levels in the Atmosphere in Mainland China: Zuo‐Wen Zhang, et al. Department of Public Health, Kyoto University Faculty of Medicine—The 1984‐1997 retrieval of Chinese papers yielded 16 reports on the lead (Pb) and cadmium (Cd) levels in air of the general environment in Mainland China, in which Pb and Cd levels were reported in 29 and 10 cases, respectively. The reported values are scattered over a wide range of 0.08 to 2.69 μg/m3 for Pb and 0.001 to 0.07 μg/m3 for Cd. The combination of high‐volume air sampling and atomic absorption spectrometry (either graphite furnace or flame) was the common method. Difference in sampling sites within the same study region and seasonal changes are among the factors identified to induce variation. No substantial difference was detected among regions with various degrees of urbanization, and trends over recent years were not remarkable both in Pb and in Cd levels. The grand geometric mean for Mainland China was thus estimated to be 0.25 μg/m3 for Pb and 0.01 μg/m3 for Cd. These values appear to be several times higher than those reported for Japan (i.e., 0.01 to 0.08 μg/m3 for Pb and 0.001 to 0.003 μg/m3 for Cd).