Hexachlorocyclohexane and dichlorodiphenyltrichloroethane residues in the dustfall of Tianjin, China.
Heating and nonheating season dustfall samples were collected from 23 sites in Tianjin, China during 2002-2003 to determine residues of hexachlorocyclohexane isomers (a-HCH, beta-HCH, gamma-HCH, and beta-HCH) and dichlorodiphenyltrichloroethane and metabolites (p,p'-DDE, p,p'-DDD, and p,p'-DDT). Concentrations of sumHCH (sum of alpha-, beta-, gamma-, and delta-HCH) and sumDDT (sum of p,p'-DDE, p,p'-DDD, and p,p'-DDT) varied in ranges of 10.9-3.16 x 10(3) and 37.9-1.53 x 10(3) ng g(-1) dry weight in heating season and in ranges of 6.9-1.12 x 10(3) and 18.6-626 ng g(-1) dry weight in nonheating season, respectively. It was found that HCHs and DDTs concentrations of the most heating season samples were higher than those of nonheating season samples collected from the same sites. Among studied compounds of the HCH family, beta-HCH prevailed in most samples, suggesting a possible volatilization or resuspension from contaminated topsoil. As for DDTs, p,p'-DDT and p,p'-DDE prevailed in most samples, indicating a possible "fresh" input. Correlations between HCHs/DDTs and total organic carbon and particle size are discussed. Atmospheric deposition fluxes were calculated for the heating and nonheating seasons, and the results showed that the annual input of particulate sumHCH and sumDDT from air to surface in the studied area of 1.19 x 10(4) km2 were 89 t and 80 t, respectively.
Wu
Shui-Ping
SP
Laboratory for Earth Surface Processes, College of Environmental Sciences, Peking University, Beijing, PR China.
Tao
Shu
S
Lan
Tian
T
Li
Ben-Gang
BG
Cao
Jun
J
Liu
Wen-Xin
WX
Liu
Yu
Y
Meng
Bing-Jun
BJ
D000388:Air / Q000032:analysis* / Q000592:standards; D000393:Air Pollutants / Q000032:analysis*; D002681:China; D002947:Cities; D003634:DDT / Q000032:analysis*; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring; D001556:Hexachlorocyclohexane / Q000032:analysis*; D012621:Seasons
D000393:Air Pollutants; D004391:Dust; D001556:Hexachlorocyclohexane; D003634:DDT