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The Status of Pesticide Residues in the Drinking Water Sources in Meiliangwan Bay, Taihu Lake of China 总被引:10,自引:0,他引:10
The study was carried out to assess the levels of pesticide residues in the water of Meiliangwan Bay, Taihu Lake of China. The most commonly employed organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs) and herbicide atrazine were analyzed. The water samples were collected seasonally from Meiliangwan Bay within a period of one year. The pesticides were analyzed by gas chromatography (GC) with μECD or NPD after solid-phase extraction (SPE), which was confirmed by GC with an ion trap mass spectrometry (MS). The mean concentrations were 1.98 ng/l for lindane, 0.378 ng/l for heptachlor epoxide, 0.367 ng/l for p,p′-DDE, 0.496 ng/l for p,p′-DDD, 1.06 ng/l for p,p′-DDT and 51.6 ng/l for dichlorvos, 39.0 ng/l for demeton, 346 ng/l for dimethoate, 4.12 ng/l for methyl parathion, 11.6 ng/l for malathion, 2.17 ng/l for parathion and 217 ng/l for atrazine. Generally, low concentrations of OCP were found, whereas the concentrations of the OPPs and atrazine in the water of Taihu Lake were relatively high. Heptachlor epoxide and lindane were the two most commonly encountered OCPs while dichlorvos, demeton and dimethoate were found to have much higher concentrations and occurrences than other OPPs. 相似文献
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采用超高效液相色谱-电喷雾二级质谱联用技术同时测定水中7种抗生素,优化了试验条件.磺胺甲恶唑、诺氟沙星、环丙沙星、氧氟沙星、四环素在1.00 ng/L~1000 ng/L范围内线性良好,定量下限为1 ng/L,土霉素、金霉素在10.0 ng/L-2 000 ng/L范围内线性良好,定量下限为10 ng/L,去离子水和地表水样加标回收率为72.1%-112%,RSD为0.6%~9.2%. 相似文献
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网格监测统计积分模式的推导与应用 总被引:1,自引:0,他引:1
把大气污染物的空间分布看成是连续变化的超曲面,采用积分法推导网格监测点位均值的积分模式,并由此推导监测范围内污染物总量模式。利用丹东市环境空气SO2被动扩散网格监测数据,采用此模式计算其趋势值和均值。 相似文献
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Xiang Yang Sun Cheng Da Gao Lin Zhang Su Yan Li Yong Qiao 《Environmental monitoring and assessment》2011,175(1-4):193-200
CO2 release from forest soil is a key driver of carbon cycling between the soil and atmosphere ecosystem. The rate of CO2 released from soil was measured in three forest stands (in the mountainous region near Beijing, China) by the alkaline absorption method from 2004 to 2006. The rate of CO2 released did not differ among the three stands. The CO2 release rate ranged from ??341 to 1,193 mg m???2 h???1, and the mean value over all three forests and sampling times was 286 mg m???2 h???1. CO2 release was positively correlated with soil water content and the soil temperature. Diurnally, CO2 release was higher in the day than at night. Seasonally, CO2 release was highest in early autumn and lowest in winter; in winter, negative values of CO2 release suggested that CO2 was absorbed by soil. 相似文献
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建立了加速溶剂萃取、凝胶渗透色谱(GPC)与气相色谱-质谱联用测定土壤中6种氯代多环芳烃的分析方法。研究证实该法的最佳萃取条件为:10.34 MPa压力,100 ℃萃取温度下,以1∶1(V/V)的正己烷/二氯甲烷为萃取溶剂,静态萃取10 min,循环4次。GPC净化过程用乙酸乙酯和环己烷的混合液1∶1(V/V)做洗脱液,目标物的收集时间为25~35min。方法对Cl-PAHs在1~500 μg/L范围内线性良好,相关系数R2为0.998 4~0.999 7;LOD和LOQ分别为2.6~25.1 pg/g和8.7~83.6 pg/g;各目标物的低浓度回收率为64.1%~117.6%,RSD<12.05%;高浓度回收率为59.1%~105.3%,RSD<9.81%。研究证实该法满足定量分析的要求,并应用该法对某化工园进行了氯代多环芳烃的检测。 相似文献
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采用石英毛细管作为模具,甲基丙烯酸和乙二醇二甲基丙烯酸酯在石英纤维表面原位聚合得到聚(甲基丙烯酸-乙二醇二甲基丙烯酸酯)作为固相微萃取涂层,并以五氯酚为研究对象,采用顶空SPME-GC-ECD法对该涂层的萃取性能进行评价。使用正交试验优化萃取温度、萃取时间、盐浓度、pH和搅拌速度。在最优条件下,建立了水样中五氯酚的分析方法,方法检出限为1ng/L,线性范围为2~5000ng/L,线性相关系数为0.9999,相对标准偏差(RSD,n=5)为8.9%,加标回收率为110.8%。 相似文献
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利用自制被动采样装置,在2011年秋冬季对南京市部分地区室内空气中5种气态多环芳烃(PAHs)(萘、苊烯、苊、芴、菲)进行了为期100d的连续采样检测,被动采样器的采样速率为0.012m3/d,5种PAHs的回收率在63%~105%之间,方法检出限在1.1~2.4ng范围内。结果表明,南京市5处不同室内环境空气中萘的浓度最高,占总量的90%以上。室内环境空气中5种PAHs的总浓度为230~1564ng/m3。住宅内人体对5种PAHs的暴露速率为479~560ng/h。 相似文献