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1.
北京工业废水和城市污水中有机氯农药残留分析   总被引:2,自引:0,他引:2  
建立了基于HLB固相萃取柱和气相色谱-电子捕获(GC-ECD)测定水体中有机氯农药的方法,并对方法的回收率、灵敏度进行了评价,同时分析了北京市七类典型污染点源50个采样点位有机氯农药的浓度,检测到的有机氯农药包括γ-六六六、β-六六六、4,4’-滴滴涕、α-六六六、δ-六六六、硫丹Ⅰ、4,4’-滴滴伊、艾氏剂和异狄氏剂,它们的检出率分别为90%、60%、50%、46%、26%、8%、6%、2%和2%。主要有机氯农药污染残留为γ-六六六、β-六六六和4,4’-滴滴涕。检出有机氯农药浓度范围是0.20~76.40ng/L。方法对有机氯农药的回收率达到60.93%~141.50%,方法检测限为0.27~2.90ng/L。  相似文献   

2.
贵州遵义地区土壤中有机氯农药残留调查   总被引:6,自引:2,他引:4       下载免费PDF全文
于2008年3月-5月对遵义地区土壤中有机氯农药残留进行了调查。结果表明,15种有机氯农药在所有样品中都有不同程度的检出。HCHs、DDTs类物质的检出率分别为90.7%、45.7%。∑HCH残留量为未检出~12.7μg/kg,平均值为1.6μg/kg;2DDT残留量为未检出-239.7μg/kg,平均值为2.8μg/kg;总有机氯杀虫剂平均残留量为4.51μg/kg,同国内其他地区相比,其残留水平偏低。  相似文献   

3.
一、目的意义 本次调查研究的目的,是为了搞清我区粮食受有机氯农药污染的现状,获取我区粮食污染监测的最新数据,推算出我区粮食总体中六六六、DDT残留的未检出率和检出超标率,对粮食受有机氯农药污染做出总体评价,最终为粮食生产和管理部门的有关决策提供依据,同时也为我区的农业环境监测在方法学上创出一条路子。  相似文献   

4.
广西北部湾蔬菜种植基地土壤中代森锌类农药残留调查   总被引:1,自引:0,他引:1  
采用顶空-气相色谱-质谱法,对南宁、北海、钦州和防城港等4个北部湾区域城市蔬菜种植基地60份土壤样品中的代森锌类农药残留进行检测。结果表明,南宁市的15份土壤样品均未检出代森锌类农药残留;北海市有5份土壤样品检出代森锌类农药残留,检出率为33.3%,其质量比范围为0.005 2 mg/kg~0.034 6 mg/kg;钦州和防城港2市30份土壤样品均检出代森锌类农药残留,检出率为100%,其质量比范围为0.004 9 mg/kg~0.674 mg/kg。  相似文献   

5.
南四湖表层沉积物中有机氯农药的含量及分布特征   总被引:3,自引:0,他引:3  
利用气相色谱-电子俘获检测(GC-ECD)方法对南四湖表层沉积物中13种有机氯农药进行了分析测定。每个采样点均检出了有机氯农药,与世界其它类似水体比较,南四湖表层沉积物中的有机氯农药处于低水平含量,属于低生态风险水平。多数点位有机氯农药均是由于历史上使用造成的,但不排除个别点位存在新的污染源。  相似文献   

6.
调查了深圳市10条主要河流农药类环境激素的污染现状。结果表明,深圳市各河流均受到农药类环境激素的污染,共有15种农药类环境激素被检出,质量浓度为未检出-4.8μg/L。并推荐深圳市河流中优先控制的农药类环境激素为:六六六、α-氯丹、硫丹I、环氧七氯、六氯苯、氟乐灵、联苯菊酯、二硫代农药。  相似文献   

7.
采集了湖北省武汉、宜昌、襄阳地区的45个菜地土壤样品,测定其中11种有机氯农药的残留量,并对其残留特征和污染来源进行了研究分析。结果表明,所有土壤样品中均检出有机氯农药,但大多数点位的污染物含量均低于相关标准限值,通过数据统计和因子分析法得出p,p’-DDT、p,p’-DDE为主要污染物。计算特征比值后发现,该地区滴滴涕污染可能源于传统工业滴滴涕和三氯杀螨醇的混合源,既有早期污染也有新污染的输入,六六六污染主要源于林丹,氯丹残留主要源于早期污染。  相似文献   

8.
测定了不同典型农业生产功能区土壤中有机氯农药(OCPs)残留,六六六(HCHs)、滴滴涕(DDTs)各同分异构体均有不同程度检出。结果表明,DDTs含量占有机氯农药含量的56%~95%,是污染的主要贡献污染物。HCHs中γ-HCH占45%~79%,DDTs中DDE>40%。其畜禽养殖基地和污水灌溉区污染指数(DDTs)分别为1.6(重污染)和0.6(中污染),其余均小于0.5(轻污染)。  相似文献   

9.
对南通地区48个鳗鱼养殖场的养殖水及鳗鱼进行了有机氯农药残留量的调查。结果表明,该地区人工养殖场的养殖水和鳗鱼体中六六六、DDT均有检出,但其含量大大低于国家渔业水质标准和国家食品卫生标准。  相似文献   

10.
采集了乌江流域中上游30个采样点的60个水样品,用液-液萃取对样品进行前处理,然后用GC-ECD测定有机氯农药含量,分析有机氯农药残留现状。结果表明,有机氯农药在样品中都有不同程度的检出,其中六六六、滴滴涕类物质的检出率分别为90.7%、46.9%,质量浓度为4.03~42.89 ng/L,同我国其它区域相比,乌江流域中上游水体中的有机氯含量处于中等水平,低于相应的标准限值。故就有机氯农药这类污染物在水中的含量来说,乌江流域中上游的水体是相对安全的。但由于这类污染物是持久性的,因此它们在水环境中的存在和影响也是不容忽视的。  相似文献   

11.
The extent of contamination by endosulfans in soil samples collected from the Point Mugu watershed near Oxnard, California was determined using capillary gas chromatography/mass selective detection (GC/MSD). The study was designed to detect three organochlorinated pesticides: endosulfan , endosulfan and endosulfan sulfate. Thirteen sets of two soil samples each were taken from various sites in the region. Our results show that the endosulfan levels in these soils range from trace amounts to nearly 30 ppm, with endosulfan being the most abundant and endosulfan sulfate the least. Two sites of the study, Hueneme and Revolon and Farm and Revolon, showed high amounts of endosulfans and , with concentrations between 20 and 30 ppm. The majority of the other sites studied in this research produced concentrations of less than 10 ppm for each of the three endosulfans monitored. At five areas in particular, Pleasant Valley and Creek, Laguna and Creek, Etting and Creek, Road and Creek and Hueneme and Creek, less than 2 ppm or only trace amounts of endosulfans , and sulfate were detected.  相似文献   

12.
Water samples from the Chao Phraya River, the main river in Thailand were collected and analyzed during 1988–1994. Organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and chlordanes were determined. Aldrin and dieldrin had high frequencies of occurrence in water samples. The concentration median of the pesticides was approximately one order of magnitude higher than those of total HCHs and DDTs. Levels of aldrin were relatively high in the upstream while levels of DDTs were high in the urban area of Bangkok during 1989–1990. p,p-DDE levels were relatively higher in 1992. No clear trends in the levels of pesticides were observed.  相似文献   

13.
Rapid increase in industrialization and agricultural activities to meet the population need has led to environmental pollution. The major revolution in agricultural production is mainly due to increased use of pesticides and fertilizers. Soil act as a major sink for majority of pesticides applied on agricultural crops. Among the organochlorines, endosulfan is the most commonly used pesticide, hence this study concentrates on the persistence and distribution behaviour of endosulfan under field conditions. The result showed that the alpha endosulfan concentrations were very minimum (0.98 mg/kg of soil) in all the four fields under study (Nazarath, Othikadu, Ekkadu and Ekkadukandigai of Thiruvallur district, Tamil Nadu). Where as beta endosulfan concentration at the time of application was 6.39 mg/kg and declined to 0.8 mg/kg on soil at 150th day. The endosulfan sulfate concentration was 11.8 mg/kg in soil at 15th day and then concentration declined to 2.2 mg/kg at 150th day. Field run-off samples showed maximum residue levels (0.024 mg/l) at the early irrigation period. While plant foliar parts showed maximum concentrations of α-endosulfan (43.4 mg/kg), β-endosulfan (40.6 mg/kg) and endosulfan sulfate (20.1 mg/kg). At harvest stage, rice grain and husk also had lower concentrations of endosulfan sulfate (2.2 and 0.09 mg/kg), respectively.  相似文献   

14.
河流沉积物中有机污染物的分析研究进展   总被引:8,自引:2,他引:6  
总结了近年来河流沉积物中有机污染物的研究进展 ,集中评述了国内有关沉积物中多环芳烃、有机氯农药和多氯联苯的分析研究现状 ,包括样品采集、样品前处理和样品分析 ,并对今后河流、湖泊及水库沉积物中污染物的分析工作作了展望  相似文献   

15.
Persistent organic pollutants (POPs) such as chlorinated pesticides are of global concern due to their widespread occurrence, persistence, bioaccumulation and toxicity to animals and human. This paper summarises recent research on 18 chlorinated pesticides in an important catchment in China, by determining their concentrations and behaviour in water, sediment, soil and plants. The concentrations of the total pesticides were in the ranges 187-893 ng l(-1) in river water, 8.53-210 ng g(-1) dry weight in soil, 2.66-13.45 ng g(-1) dry weight in river sediment, and 651-2823 ng g(-1) dry weight in plants. The predominance of beta-HCH as the major isomer of HCHs in all water, soil, sediment and plant samples was clearly observed, due to beta-HCH's resistance to biodegradation. On average beta-HCH accounted for 44%, 53%, 50%, and 46% of the total HCH concentration in water, soil, sediment and plant, respectively. Of the DDTs, DDE accounted for 48%, 43%, 53%, 55% of the total DDT, which suggested that DDT had been transformed to its metabolites, DDE and DDD, of which DDE was the more stable. The chlorinated pesticide levels in the River Wuchuan were generally below the guideline values in China, but some sites displayed levels in excess of EC Environmental Quality Standards for HCHs and DDTs. The results therefore provide important information on the current contamination status of a key agricultural watershed in China, and point to the need for urgent actions to evaluate the long-term fate and toxicity of such persistent compounds and an appropriate remediation strategy.  相似文献   

16.
Animal products like milk and meat are often found to be contaminated with residues of persistent pesticides and other toxic substances. The major source of entry of these compounds to animal body is the contaminated feed and fodder. So, unless the residues are managed at this stage, it is very difficult to prevent contamination in milk and meat. Therefore, the status of residue level of most persistent organochlorinated pesticides (OCP) in feed and fodder should be monitored regularly. The frequency of occurrence and contamination levels of OCP residues in different kinds of animal concentrate feed and straw samples collected from Bundelkhand region of India were determined. Out of 533 total samples, 301 i.e. 56.47% samples were positive containing residues of different OCPs like hexachlorocyclohexane (HCH) isomers, dichlorodiphenyltrichloroethane (DDT) complex, endosulfan and dicofol. Among different HCH isomers, the mean concentration of ??-HCH was highest, and total HCH varied from 0.01 to 0.306 mg kg???1. In case of DDT complex, i.e. DDD, DDE and DDT, the concentration ranged between 0.016 and 0.118 mg kg???1 and the pp| isomers were more frequently encountered than their op| counterparts. Endosulfan was also found in some samples in concentration ranging from 0.009 to 0.237 mg/kg, but dicofol could be recorded in very few samples. Although feed samples were found to contain OC residues, after comparing their levels in positive samples with the limiting values of respective pesticides, only very few were found to exceed the threshold level. Otherwise, they were mostly within safe limits.  相似文献   

17.
The increasing application of pesticides in the uplands of northern Thailand has increased the transfer of pesticides to surface water. To assess the risk of pesticide use for stream water quality, we monitored the concentrations of seven pesticides (atrazine, dichlorvos, chlorpyrifos, dimethoate, chlorothalonil, (α-, β-) endosulfan, cypermethrin) frequently used in the Mae Sa watershed (77 km2) in water and sediment samples over a period of one and a half years (2007–2008). All investigated pesticides were recorded in the river. Chlorpyrifos was detected most often in water samples (75 % at the headwater station), while cypermethrin was most often found in riverbed (86 %) and in all suspended sediment samples. The highest concentrations of the pesticides were detected during the rainy season. About 0.002 to 4.1 % by mass of the applied pesticides was lost to surface water. The risk assessment was based on the risk characterization ratio (RCR). The RCRs of dichlorvos in water, (α-, β-) endosulfan, and cypermethrin in water and sediments were higher than unity indicating that they are likely to pose a threat to aquatic ecosystem. Finally, we discuss the role of sampling design on ecotoxicological risk assessment. Our study shows that pesticide contamination of surface waters is an environmental issue in the Mae Sa watershed and that measures need to be undertaken to reduce the loss of pesticides from soil to surface waters.  相似文献   

18.
A range of organochlorinated compounds have been consumed in China, India and the countries of mainland southeast Asia (MSA). Considering their persistence in the environment and ability in long-range atmospheric transport (LRAT), the potential outflow of these compounds from this region is therefore of great concern in the context of the global distribution of toxic chemicals. As part of a monitoring campaign aimed at investigating the LRAT of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) from southern China, MSA and northern India, atmospheric levels of OCPs and PCBs were measured once a week from October 2005 through December 2006 at Tengchong Mountain (TM), a remote site located in south-western China. The average concentrations of OCPs were found to be higher than those in other remote stations in the Arctic and the Tibetan plateau, except for α-hexachlorocyclohexane (α-HCH). A high level of β-HCH and low α-HCH/β-HCH ratio was attributed to an accidental release of β-HCH from unknown sources, besides obvious evidence of lindane (γ-HCH) and technical HCH usage. Temporal variations of chlordanes and endosulfan were related to the usage pattern of these compounds, as well as LRAT. In contrast, dichlorodiphenyltrichloroethane (DDT) exhibited a relatively minor seasonal variation. The OCP levels at the monitoring site were found to be related to the air parcel back trajectories on the basis of four distinct clusters. Elevated levels of HCHs and DDTs were observed when air parcels originated from northern India where considerable OCP usage was reported recently, while high levels of γ-HCH and TC (trans-chlordane) were mainly associated with air masses from southern China and northern MSA. The study highlighted the high background level of OCPs as well as their temporal patterns of trans-boundary LRAT in the MSA region.  相似文献   

19.
Yamuna, a prominent river of India covers an extensive area of 345,843 km(2) from Yamunotri glacier through six Indian states. Residues of organochlorine pesticides (OCPs) namely, isomers of HCH and endosulfan, DDT and its metabolites, aldrin, dieldrin, were analysed in water of river Yamuna along its 346 km stretch passing through Haryana-Delhi-Haryana and the canals originating from it. beta-HCH, p.p'-DDT, p.p'-DDE and p.p'-DDD had maximum traceability in test samples (95-100%) followed by gamma-HCH, alpha-HCH and o.p'-DDD (60-84%) and o.p'-DDT, delta-HCH and o.p'-DDE (7-30%) while aldrin, dieldrin, alpha and beta endosulfan remained below detection limits (BDL). The concentration of SigmaHCH and SigmaDDT at different sites of the river ranged between 12.76-593.49 ng/l (with a mean of 310.25 ng/l) and 66.17-722.94 ng/l (with a mean of 387.9 ng/l), respectively. In canals the values were found between 12.38-571.98 ng/l and 109.12-1572.22 ng/l for SigmaHCH and SigmaDDT, respectively. Water of Gurgaon canal and Western Yamuna canal contained maximum and minimum concentration, respectively both of SigmaHCH and SigmaDDT residues. Sources of these pesticides and suggested measures to check pesticide pollution of this major Indian river, keeping in view its vital link with life, are discussed in this paper.  相似文献   

20.
Modern agriculture practices reveal an increase in use of pesticides and fertilizers to meet the food demand of increasing population which results in contamination of the environment. In India crop production increased to 100% but the cropping area has increased marginally by 20%. Pesticides have played a major role in achieving the maximum crop production, but maximum usage and accumulation of pesticide residues was highly detrimental to aquatic and other ecosystem. The present study was chosen to know the level of organochlorines contamination in ground water of Thiruvallur district, Tamil Nadu, India. The samples were highly contaminated with DDT, HCH, endosulfan and their derivatives. Among the HCH derivatives, Gamma HCH residues was found maximum of 9.8 μg/l in Arumbakkam open wells. Concentrations of pp-DDT and op-DDT were 14.3 μg/l and 0.8 μg/l. The maximum residue (15.9 μg/l) of endosulfan sulfate was recorded in Kandigai village bore well. The study showed that the ground water samples were highly contaminated with organochlorine residues.  相似文献   

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