Residues of Hexachlorocyclohexane Isomers and Their Distribution Characteristics in Soils in the Tianjin Area, China

Abstract

Hexachlorocyclohexane (HCH) has a history of use in China. This paper presents the results of an investigation of HCH residue isomers and their distribution characteristics in soils near Tianjin, China. One hundred eighty-eight soil samples were collected from the Tianjin area. Four HCH isomers-alpha-HCH, beta-HCH, gamma-HCH, and delta-HCH-were detected using gas chromatography for all samples. Concentrations of the sum HCH ranged from 1.3 to 1095 ng g(-1), among which beta-HCH accounted for 52.5%. In addition, residues of HCH within Tianjin's urban areas were found to be higher. No significant differences were found between the residues of HCH in soils from waste irrigation areas and those in other areas. Total organic carbon content was determined to impact the residue levels of HCH in soils, while pH value and clay content were not related to concentrations of HCH. In general, all HCH isomers in soil samples had abnormally high residue levels, possibly the result of continuous use of HCH in this area.

Regional differences and sources of organochlorine pesticides in soils surrounding chemical industrial parks

“…The mean concentrations of ΣDDT, ΣHCH and HCB were higher than those reported earlier in China (Table 5). Especially, ΣHCH concentrations were 14.5 times as much as that in Tianjin (Gong et al 2004b). The extremely high ΣDDT and ΣHCH concentrations in several samples close to the chemical industrial parks indicate that these sites are heavily polluted.…”

Levels and distribution of organochlorine pesticides in various media in a mega-city, China

“…It was one of the most common OCP pollutants in the studied environmental media. The ratio of a-HCH/ c-HCH is relatively stable, with a value of 4.64-5.83 for technical HCHs, and almost zero for lindane Gong et al, 2004), and it can thus be used to monitor the HCH source (Kim et al, 2002). In the present study, the ratio of a-HCH/c-HCH varied from 0-3.6, a-HCH can be transported through the atmosphere for considerable distances, indicating the presence of a potential emission source of lindane (Brubaker and Hites, 1998).…”

Occurrence of polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls pollution in sediments from the Haihe River and Dagu Drainage River in Tianjin City, China

“…As a traditional base of chemical industry in China, Tianjin has produced chloralkli, technical HCH, lindane, chlorobenzene, and pentachlorophenol (PCP) for nearly 30-50 years (Gong et al, 2004;Hu et al, 2005). Although the production of PCP (Na) has been generally forbidden, it is still manufactured by one of plants in this area for controlling the spreading of snailborne schistosomiasis in the south of China.…”