Atmospheric particulate mercury concentration and its dry deposition flux in Changchun City, China

From July 1999 to January 2000, we determined the particulate mercury HgŽp. concentration in the atmosphere of five function sites and one contrast site in the city of Changchun, China. During non-heating season, the HgŽp. concentration in air in urban areas ranged from 0.022 to 0.398 ng m 3 with an average of 0.145 ng m 3, and at the contrast site with an average of 0.084 ng m 3. During the heating season, the HgŽp. concentration in urban areas was in the range of 0.148 1.984 ng m 3 with an average of 0.461 ng m 3 and with an average of 0.211 ng m 3 at the contrast site. The HgŽp. concentration during heating season is two times higher than that during non-heating time. Coal burning and wind-blown soil material are the two important sources of HgŽp.. Wind-blown soil material contributes 7.9 38.5% to the HgŽp. with an average of 24.1% in urban area. A theoretical model was used to estimate the dry deposition flux, with results of 43.06 g m 2 a 1 in the urban area and 21.28 g m 2 a 1 at the contrast site.