In this study,investigations were conducted on residues of organochlorine pesticides(OCPs)in soils in Zhanjiang city,China.A total of 61 soil samples were collected from sites which were representative of the region for analysis of contents of OCPs.And with the aid of multi-variate geostatistics and GIS,residues and spatial distributions of 17 types of OCPs were analyzed.Results show that the 17 OCPs were detected.various in contents of allthe soil samples.HCHs and DDTs residues were below the criteria of the national standards for soil environment quality.Residue content of 13-HCH was the highest among HCHs,indicating some recent input of HCH to soils,while for DD T,no sign of new input was found.Principal component analysis demonstrated that the 17 OCPs in the soil may have 6 major contributors,corresponding respectively to the use of industrial HCH and lindane,plant diseases and insect pests and the pesticide use,etc.By means of ordinary Kriging interpolation,studies on spatial distribution of OCPs showed that the 17 OCPs varied greatly in spatial distribution between types.选取位于中国大陆最南端的湛江市为研究区域,对该市土壤进行了系统采样分析,测定了61个表层土壤样品中的17种有机氯农药的含量.利用多元地统计和GI S相结合的方法,研究了17种有机氯农药的残留状况及空间分布情况.结果表明,17种有机氯农药在42个土壤样品中均有不同程度的检出,其中P,P'-D DE检出率为100%,3种有机氯农药检出率在90%以上.其中六六六和滴滴涕残留较普遍,六六六未达到污染水平,有一个土壤样品滴滴涕超过国家土壤环境 质量一级标准.分析显示,近期可能仍有新的六六六输入土壤环境,而滴滴涕则主要来自过去施用农药的残留.主成分分析显示17种有机氯农药町以由6个主成分 反映,分别对应于工业HCH和林丹的使用、农药使用习惯以及当地病虫害特点等.采用克里格插值法对有机氯农药在研究区的空间分布进行了研究,结果表明不同 有机氯农药在研究区分布存在很大差异.
Investigations on residues of organochlorine pesticides(OCPs) in soils in Huizhou,China were conducted.A total of 42 soil samples were collected from sites representative of the region for analysis of contents of OCPs.And with the aid of multi-variate geostatistics and GIS,residue and spatial distribution of 17 types of OCPs were analyzed.Results show that the 17 OCPs were detected,various in content in all the soil samples.HCHs and DDTs residues were detected,but below the criteria of the national standards for soil environment quality.Residue content of beta-HCH was the highest among HCHs,which implied some recent input of HCH to soils,while for DDT,no sign of new input was found.Compared with other regions in the country,Huizhou city was lower in soil HCH and DDT content.Principal component analysis demonstrated that the above-said 17 OCPs in the soil may have 5 major contributors,corresponding respectively to industrial use of HCH,natural factors,use of lindane,use of heptamul and use of Drinox.By means of ordinary Kriging interpolation,spatial distribution of OCPs was studied with results indicating that the 17 OCPs variaed greatly in spatial distribution between types选取位于珠江三角洲的惠州市为研究区域,对该市土壤进行了系统采样分析,测定了42个表层土壤样品中的17种有机氯农药的含量.利用多元地统计和GIS相 结合的方法,研究了17种有机氯农药的残留状况及空间分布情况.结果表明,17种有机氯农药在42个土壤样品中均有不同程度的检出,其中p,p′-DDE 检出率为100%,3种有机氯农药检出率在90%以上,6种有机氯农药的检出率在80%以上.其中六六六和滴滴涕残留较普遍,但并未达到污染水平.分析显 示,近期可能仍有新的六六六输入土壤环境,而滴滴涕则主要来自过去施用农药的残留.与国内其他地区比较,惠州市土壤HCH和DDT含量处于较低水平.主成 分分析显示上述17种有机氯农药可以由5个主成分反映,分别对应于工业HCH的使用,自然因素,林丹的使用以及七氯和艾氏剂等农药的使用.采用克里格插值 法对有机氯农药在研究区的空间分布进行了研究,结果表明不同有机氯农药在研究区分布存在很大差异
Dichlorodiphenyltrichloroethane (DDT) has been banned in China for decades, and yet high DDT concentrations are still being detected in the Chinese environment. This might be at least partly due to the current use of dicofol formulation, which contains DDT as an impurity. In this study, a method based on the ratios of two DDT isomers, o,p '-DDT and p,p '-DDT, was established and used to estimate the relative contributions of dicofol formulation and those of technical DDT to overall environmental DDT. Based on this method and field data from the literature, we calculated that dicofol formulation contributed >72% of atmospheric DDT in 2004 in the Taihu Lake region, China, and this value was >84% in summer when dicofol was applied for agricultural purposes. Sediment and soil, however, contained mostly residual DDT from the historical use of technical DDT. In most other regions of China, we found that dicofol contributed to a significant fraction of DDT in air samples. (C) 2010 Elsevier Ltd. All rights reserved.
Air and water samples were collected from Taihu Lake, East China through 2004 and analyzed for 33 congeners of polybrominated diphenyl ether (PBDE) and other seven brominated and chlorinated flame retardants. The annual concentration of total atmospheric PBDEs was 220 pg m(-3); BDE-209 was most abundant (average 41% of total PBDEs), followed by BDE-47 (17%) and BDE-28 (15%). The relative abundance of tetra- and tri-BDE congeners (including BDE-47, -28, -49, -66, and -17) instead of BDE-99 indicated that a specific penta-BDE formulation might be produced and/or consumed in this region. The source was confirmed by the analysis of air-water gas exchange, which was nearly at equilibrium in spring and summer but displayed strong volatilization flux in autumn and winter, especially for BDE-28, indicating the potential wastewater discharge of PBDEs into the lake. In addition to PBDEs, hexabromobenzene, 1,2-bis(2,4,6-tribromophenoxy)ethane, decabromodiphenylethane, and Dechlorane Plus were detected in air samples, with an annual mean concentration of 23 pg m-3 for decabromodiphenylethane, and <4 pg m(-3) for the others. (C) 2010 Elsevier Ltd. All rights reserved.