Residues of organochlorine pesticides in surface soils from college school yards in Beijing, China

Abstract

Organochlorine pesticides (OCPs) have been a major environmental issue, attracting much scientific concern because of their nature of toxicity, persistence, and endocrine disrupting effects. Soil samples were collected from ten college school yards in Beijing in 2006 and analyzed to determine fifteen OCPs. Dichlorodiphenyltrichloroethanes (DDTs) were found to be the main pollutants, accounting for 93.70% of total OCPs, followed by hexachlorohexanes (HCHs) (2.25%) and hexachlorobenzene (HCB) (1.82%). Content of chlordanes (CHLs), heptachlors (HEPTs), and endosulfans comprised 0.51%, 1.05%, and 0.79% of fifteen OCPs, respectively. The preliminary pollution assessment indicated that DDTs have caused high OCPs levels in some schools. Source identification showed that HCHs in soils were originated from an old mixed source of technical HCHs and lindane. And DDTs were mainly from mixed use of technical DDTs and dicofol containing DDT impurities. According to GB15618-1995 (guidelines of Chinese environmental quality standards for soils), HCHs and DDTs levels might be categorized as little and low polluting pesticides. This study indicated that the environmental quality of college school yards with large green land were not as good as was expected and there existed potential exposure risk of college population to OCPs.

Evaluation and characterization of thyroid-disrupting activities in soil samples along the Second Songhua River, China

“…The remaining 0.5-mL aliquots were then carefully moved to columns containing 10 g of silica and 10 g of Al 2 O 3 (Ma et al, 2007). The column was eluted with 15 mL of hexane to yield a nonpolar fraction, with 70 mL of a hexane/DCM (v/v ¼7:3) mixture to obtain a medium-polar fraction, and with 30 mL of methanol to acquire a polar fraction (Xiao et al, 2006;Wang et al, 2008). The sub-fractions were also evaporated to dryness under a gentle nitrogen flow and re-dissolved in 0.5 mL of DMSO.…”

Distribution of dichlorodiphenyltrichloroethane and hexachlorocyclohexane in urban soils and risk assessment

“…47 Levels of ∑DDT and ∑HCH in urban soils from different location in China were in the ranges of 0.7-972.2mg kg -1 and BDL-1095 mg kg -1 , respectively. [16][17][18][19][20][21][22][23][24][25][26][48][49][50][51][52] However, in agriculture soils from China, the ∑DDT and ∑HCH levels were in the ranges of 7.6-662.9 mg kg -1 and 0.2-103.9 mg kg -1 , respectively.…”

“…16 Low polluted (below 50 mg kg -1 ), light polluted (50-500 mg kg -1 ), moderate polluted (500-1000 mg kg -1 ), and heavily polluted (>1000 mg kg -1 ). Thus, the soils of Kurukshetra, Haryana, India may be classified as low polluted soil with HCHs and DDTs.…”

“…[12][13][14] In urban areas, soils are contaminated with organic contaminants such as organochlorines (OCs), consequently adults and children may get exposed to health risk through ingestion of soil from their local areas. [15][16] For this reason, it is important that soil ingestion could be considered in any risk assessments involving their potential as harmful persistent organic pollutants. [17][18][19] Previous studies in India, have reported DDT and HCH concentrations in agricultural soils from different provinces of India such as Haryana, [20][21] National Capital Region [22][23] and UP, 22,[24][25] but work has never been conducted on urban residential soils in India.…”

Distribution and Health Risk Assessment of HCHs in Urban Soils of Beijing, China

“…From 1960s to 1980s, HCHs were applied in the areas of Beijing to enhance agricultural yield and public health (Li et al 1998). Earlier studies in and around some parts of Beijing focused on the distribution of HCHs in rural soils, urban park soils, and urban schools (Zhu et al 2005;Zhang et al 2005;Li et al 2008;Wang et al 2008) and the health risk of HCHs (Yang et al 2009), respectively. However, levels of different HCHs and their associated health risks in Beijing urban soils of different land uses have not been examined.…”