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1.
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   

2.
在实际操作中,水、土壤及沉积物中有机氯农药的测定需要进行前处理,二氯甲烷、正己烷是普遍使用的溶剂,而标准物质考核样品溶剂为甲醇。采用了气相色谱-质谱的方法研究了不同溶剂对有机氯农药(α-HCH、β-HCH、γ-HCH、δ-HCH、p,p′-DDE、p,p′-DDD、o,p′-DDT、p,p′-DDT)测定的影响。结果表明,不同溶剂对待测物质的响应值是有差异的,但保留时间不变,且随着待测物浓度的增加,这种溶剂效应对大部分待测物的作用减少;溶剂的极性对有机氯农药的响应值有显著的影响,甲醇溶剂中待测物的响应值低于其他两种溶剂相;甲醇标准物质可用二氯甲烷配制,测定值满足在推荐值之内。  相似文献   

3.
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   

4.
介绍了ASE提取、硫酸磺化和GPC净化土壤中有机氯农药的试验方法,并通过对比试验、条件试验等对ASE提取土壤中有机氯农药的效果进行了验证。结果表明,温度在80~110℃,压力在1200~1800psi均适用于提取土壤中有机氯农药,20种有机氯农药除了异狄氏剂回收率偏高外,其它19种全部在50%~150%之间,相对标准偏差均在20%以内。ASE提取、GPC净化,20种农药样品加标平均回收率50%~117%;相对标准偏差3%~28%;2种替代物回收率84%~102%,相对标准偏差6%~7%。  相似文献   

5.
惠州农业土壤、灌溉水和农产品中有机氯农药的残留   总被引:1,自引:0,他引:1  
用气相色谱法(GC-ECD)对惠州市51个农业土壤样品、12个灌溉水样品和21个农产品样品中的HCHs和DDTs残留量进行了测定.HCHs平均含量分别为土壤1.66μg/kg、灌溉水5.86ng/L、农产品24.74μg/kg;DDTs平均含量分别为土壤4.98μg/kg、灌溉水2.06ng/L、农产品41.72μg/kg,土壤中有机氯农药通过多种方式进入到水体及农产品中.从HCHs和DDTs异构体组成可以看出,环境中绝大多数农药残留是由于历史上使用造成的,个别地区可能还有新的污染输入.同其它地区相比,惠州农业土壤和灌溉水中的有机氯农药残留水平较低,但农产品尤其是蔬菜中DDTs富集程度较高.  相似文献   

6.
王伟 《中国环境监测》2019,35(1):135-141
建立了基质固相分散-ASE提取-GC/MS法同时测定土壤中8种有机氯农药和16种多环芳烃的方法。对方法的线性、检出限、精密度、回收率及土壤质控样品进行了分析,结果表明,8种有机氯农药和16种多环芳烃线性良好,相关系数为0.997 5~0.999 8,方法检出限为0.39~1.57μg/kg,空白加标样品的相对标准偏差小于20%,实际土壤样品加标回收率为60.6%~125%,土壤质控样品结果均在范围内。该方法能够满足土壤中8种有机氯农药和16种多环芳烃的检测要求。  相似文献   

7.
通过优化萃取条件建立了一套土壤中有机氯农药的加速溶剂萃取方法;采用固相萃取实现了样品的净化,气相色谱负化学离子源质谱实现了高灵敏度检测,建立了一套土壤中19种有机氯农药的快速分析方法,各目标物的检出限为0.001~0.009μg/g,采用来自于不同地区的砂土、黏土、亚黏土等不同类型的样品进行加标实验,回收率为60%~120%。  相似文献   

8.
兰州市郊蔬菜基地土壤及蔬菜中有机农药污染现状调查   总被引:4,自引:0,他引:4  
通过对兰州市郊蔬菜基地土壤及蔬菜中,有机磷和有机氯农药残留量的测定,对其污染现状进行了综合分析。  相似文献   

9.
微波萃取-气相色谱法测定土壤中有机氯残留   总被引:3,自引:0,他引:3       下载免费PDF全文
采用微波萃取-硅镁吸附剂净化-气相色谱法测定土壤中有机氯农药,优化了试验条件。方法线性良好,8种有机氯农药的检出限为0.09ng/g-0.62ng/g,样品测定的RSD为2.6%-13.2%,基质加标平均回收率为93.7%-112%,质控样的测定结果与参考值相吻合。  相似文献   

10.
用丙酮和正己烷(体积比为1∶1)作溶剂,在100℃和1 500 psi的压力下,用快速溶剂萃取仪从土壤中萃取出有机氯农药,用分子筛进行脱水和净化,GC-MS进行分析,对土壤中有机氯农药进行测定。方法的检出限为0.000 4~0.000 7 mg/kg,曲线的相关系数在0.998以上。对进口标准土进行测定,回收率为77.1%~105.2%,相对误差为-22.9%~5.2%,测定结果在证书允许误差范围内。用硅藻土制成高、中、低3个浓度级别的加标回收和精密度实验,加标回收率为84.3%~101.5%,相对标准偏差为0.6%~11.4%,表明方法准确可靠,方法用于实际土壤测定时发现土壤有不同程度的有机氯农药污染。  相似文献   

11.
气相色谱法测定赤水河中段水体中14种有机氯农药的残留   总被引:1,自引:0,他引:1  
建立了用正己烷萃取,气相色谱—电子捕获(GC—ECD)测定水体中有机氯农药痕量残留的方法。结果表明:六氯苯、α-HCH、β-HCH、γ-HCH、δ-HCH、p,p′-DDD、p,p′-DDE、p,p′-DDT、艾氏剂、狄氏剂、异狄氏剂、七氯、环氧七氯、o,p′-DDT 14种农药在14 min内有较好的分离;2个不同浓...  相似文献   

12.
In this study, we screened for an economic, rapid, and efficient hypotoxic pretreatment method for organochlorine pesticides in soil samples for gas chromatography (GC) analysis. The analytical extraction efficiencies of 11 different extractants, nine types of solid-phase purification (SPP) cartridge packings, and three types of eluents for 13 organochlorine pesticides (OCPs) in spiked and natural Chinese red soil (Hydragric Acrisols) were evaluated using an ultrasonic extraction and solid-phase purification method. High percent recoveries (85-106%) were obtained for the 13 organochlorine pesticides in soil when petroleum ether/acetone/water (10:5:2, v/v) was used an extractant. They were purified using celite SPP cartridge packing and eluted with 9 mL of dichloromethane/petroleum ether (1:9, v/v). The OCPs purification pretreatment of Hydragric Acrisols, using the above method, meets the GC analysis requirements. Compared with other traditional pretreatment methods for OCPs in soil samples, this method has several advantages, such as a short extraction time, reducing the amount of solvent, having no emulsion phenomenon, and hypotoxicity to the laboratory technicians. The concentrations of 1,1,1,-trichloro-2(p-chlorophenyl)-2-(o-chlorophenyl) ethane (DDTs; 3.42-8.08 ng g(-1)) in field soils were higher than the hexachlorocyclohexane concentration (2.94-6.12 ng g(-1)). The 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE)?+?1,1-dichloro-2,2-bis(p-chlorophenyl)-ethane (p,p'-DDD)/p,p'-DDT ratio in this field soil was approximately 2.7, suggesting that no new DDT pollution source was introduced into the sampling site.  相似文献   

13.
通过对加速溶剂萃取、平行蒸发及净化方法等环节的优化实验,建立了加速溶剂萃取-凝胶净化色谱-气相色谱质谱法测定农用地土壤中23种有机氯农药的检测方法。结果表明,方法检出限为0.0034~0.0052 mg/kg;对化合物质量分数为0.25 mg/kg的土壤加标样品进行平行实验,回收率为82.0%~93.7%;测定结果的相对标准偏差(RSD)≤8.7%。对土壤有证标准质控样品进行分析,测定结果均在验收范围之内。该方法准确可靠,灵敏度较高,样品净化效果较好,能够满足农用地土壤中有机氯农药残留痕量分析的要求。  相似文献   

14.
The objective of the present study was to monitor the levels of organochlorine pesticides HCB; α-, β-, γ-HCH; pp'DDE; op'DDT; and pp'DDT in blood serum of Veracruz, Mexico inhabitants. Organochlorine pesticides were analyzed in 150 blood serum samples that constituted that which remained after clinical analyses, using gas chromatography-electron-capture detection (GC-ECD). The results were expressed as milligrams per kilogram on fat basis and micrograms per liter on wet weight. Only the following pesticides were detected: p,p'-DDE was the major organochlorine component, detected in 100% of samples at mean 15.8 mg/kg and 8.4 μg/L; p,p'-DDT was presented in 41.3.% of monitored samples at mean 3.1 mg/kg and 1.4 μg/L; β-HCH was found in 48.6% of the samples at mean 4.9 mg/kg and 2.7 μg/L; op'DDT was determined to be in only 3.3% of monitored samples at mean 2.7 mg/kg and 1.4 μg/L. The pooled samples divided according to sex showed significant differences of β-HCH and pp'DDE concentrations in females. The samples grouped according to age presented the third tertile as more contaminated in both sexes, indicating age as a positively associated factor with serum organochlorine pesticide levels in Veracruz inhabitants.  相似文献   

15.
This study reports the concentration levels and distribution pattern of the organochlorine pesticide (OCPs) residues in the soil and surface water samples collected from the northern Indo-Gangetic alluvial plains. A total of 31 soil and 23 surface water samples were collected from the study region in Unnao district covering an area of 2150 km2 and analyzed for aldrin, dieldrin, endrin, HCB, HCH isomers, DDT isomers/metabolites, endosulfan isomers (α and β), endosulfan sulfate, heptachlor and its metabolites, α-chlordane, γ-chlordane and methoxychlor. In both the soil and surface water samples β- and δ-isomers of HCH were detected most frequently, whereas, methoxychlor was the least detected pesticide. The results showed contamination of soil and surface water of the region with several persistent organic pesticides. The total OCPs level ranged from 0.36–104.50 ng g–1 and 2.63–3.72 μg L–1 in soil and surface water samples, respectively.  相似文献   

16.
The use of organochlorine pesticides has caused concern due to their effects on human health and the Malaysian aquatic ecosystem, particularly so in view of their persistent and bioaccumulative properties. Since the extent of organochlorine pesticide pollution in Malaysian waterways is unknown except for isolated instances, a systematic survey has now been carried out. Water samples from various rivers were extracted, cleaned up with Florisil and analysed for the individual organochlorine pesticides by gas chromatography (GC) with an electron capture detector (ECD). DDE, DDT and heptachlor were present in all the river water samples of the west coast of Peninsular Malaysia. Other organochlorine pesticides were also identified from the water samples. However, the levels of all these are still below criteria values for Malaysian aquatic life, indicating that organochlorine pesticide pollution is less of a problem than other organic or inorganic pollutants.  相似文献   

17.
建立QuEChERS-气相色谱法同时检测土壤中8种有机氯农药的方法,优化分散固相萃取剂用量。土壤样品通过分散固相萃取净化技术,氮吹浓缩后用正己烷定容,最后通过气相色谱测定。结果表明,在2.0~100μg/L质量浓度范围内呈线性,相关系数r为0.9895~0.9991。空白样品在0.5,5和20μg/kg加标浓度下的回收率为75.3%~92.3%,相对标准偏差为3.2%~5.6%(n=5),方法检出限为0.053~0.064μg/kg,测定下限为0.21~0.26μg/kg。该方法操作简单、结果准确、有机试剂用量少、分析成本低,适用于土壤中有机氯农药的残留检测与分析。  相似文献   

18.
Assessment of levels of pesticide residues in vegetables was carried out in some villages in the Western Usambara and Uluguru Mountains of Tanzania where varieties of vegetables are grown. Tomatoes and cabbages were the most popular enterprise grown all year round and therefore were selected as the model crops for this study. Analysis of the cleaned sample extracts on a gas chromatography with electron capture detector (GC-ECD) and confirmation on the Gas chromatography–mass spectrometry (GC-MS) revealed dominance of organochlorine pesticides. Organophosphorous pesticides (parathion and marathion) were only detected in some samples, however, in most cases with higher concentrations compared to organochlorine pesticides. Levels of pesticide residues detected in vegetables were up to: parathion 5.07 μg/Kg, marathion 3.73 μg/Kg, α-endosulfan 0.32 μg/Kg, β-endosulfan 0.53 μg/Kg, dieldrin 1.36 μg/Kg, γ-HCH 0.25 μg/Kg, α-HCH 0.09 μg/Kg, and p, p′-DDT 0.64 μg/Kg. These results clearly show that vegetables are contaminated with different pesticide residues. However, the total levels of pesticide residues in both tomatoes and cabbages are lower than their respective codex alimentarius maximum residue levels (MRLs). This means that the vegetables produced in the area are suitable for human consumption.  相似文献   

19.
In this study, 24 organochlorine pesticide residues in 109 different honey samples collected from stores and open markets in Konya, Turkey were analyzed by gas chromatography-electron capture detection. Aldrin, cis-chlordane, trans-chlordane, oxy-chlordane, 2,4 -DDE, and 4,4 -DDE were found in all honey samples. The mean value was 0.0540 μg g???1 for oxy-chlordane. In the 55 samples of 109, levels of organochlorine pesticide residues of oxy-chlordane were determined as higher than those of Turkish Alimentarius Codex maximum residual limits (MRLs). Other organochlorine pesticide residues also exceeded MRLs except for cis-heptachlor epoxide and α-hexachlorocyclohexane. Since all of the honey samples are found contaminated and most of these samples exceeded MRLs, a control of organochlorine pesticide residues in honey is necessary for consumer health.  相似文献   

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