α-Endosulfan Removal from Water by Adsorption over Natural Clays from Burkina Faso: An Isothermal Study

The present study carried out the α-endosulfan removal from water by adsorption over natural clays from the western region of Burkina Faso. The adsorption experiments were performed over raw clay samples at room temperature in batch reactor and the obtained adsorption isotherms were well fitted by Fowler-Guggenheim model. It was pointed out for all samples that α-endosulfan was physisorbed in the interlayer space of the clay samples. The maximal adsorption capacities were respectively about 9.12, 6.98 and 4.13 mg/g for KO2, KO1 and KW1 samples. The differences in terms of adsorption capacity for the three samples were due to the presence of illite in the samples KO2 and KO1 when the KW1 sample contained essentially kaolinite in its structure. When the interlayer space was large enough as for samples with illite a greater amount of α-endosulfan molecules were adsorbed. It was also shown that the samples with the higher surface area were the most efficient for the removal of α-endosulfan molecules from water. Moreover, this study exhibited that the α-endosulfan adsorption depended on the crystallites size;the samples presenting largest crystallites had the greatest adsorption capacities.

气相色谱-负离子化学电离质谱法测定水产品中残留的硫丹及其代谢物

建立了水产品中α-硫丹、β-硫丹及硫丹硫酸酯残留量的分析方法。样品经丙酮-正己烷混合溶剂提取、转溶至乙腈中、冷冻去除油脂、活性炭和中性氧化铝固相萃取小柱（SPE）串联净化处理后，以选择离子方式进行气相色谱-负离子化学电离质谱分析，采用外标法定量。硫丹和硫丹硫酸酯的选择离子分别为m／z406，408，404，372和m／z386，388，384，422。每种化合物的最低定量检测限为0．5μg／kg，回收率为83％～105％，相对标准偏差低于13％。该方法简单、快速、准确，能满足水产品中硫丹残留的检测需要。

气相色谱法测定水产品中硫丹及其代谢物残留

建立水产品中α-硫丹、β-硫丹、硫丹硫酸酯残留的气相色谱分析方法。样品经乙腈-乙酸乙酯(4:1,V/V)提取、冷冻除脂、石墨化碳黑-佛罗里硅土和中性氧化铝固相萃取柱串联净化,以电子捕获-气相色谱测定,外标法定量。硫丹各组分在0.001～0.2μg/mL范围内线性关系良好(r≥0.9996);当α-硫丹、β-硫丹、硫丹硫酸酯在对虾、草鱼、牡蛎和鳗鲡中的添加量为1、10、20μg/kg三个水平时,回收率在74.1%～106%之间,相对标准偏差(RSD)为1.22%～7.79%;α-硫丹、β-硫丹、硫丹硫酸酯的检出限(LOD)分别为0.035、0.06、0.06μg/kg,最低定量限(LOQ)均为1.00μg/kg。适用于鱼类、甲壳类、贝类中硫丹及其代谢物污染的监测。

GC-MS/MS法测定水产品中残留硫丹及代谢物

建立水产品中α-硫丹、β-硫丹及硫丹硫酸盐残留量的分析方法。样品经乙腈溶液提取,浓缩后过凝胶柱净化,以选择反应监测离子(selected reaction monitoring,SRM)方式进行气相色谱-三重四极杆质谱联用法(gas chromatography-triple quadrupole mass spectrometer,GC-MS/MS)分析,采用外标法定量。硫丹在0.004μg/m L^0.5μg/m L范围内线性关系良好(R2>0.999),该方法的定量检出限为0.004 mg/kg,回收率为73.6%~96.2%,相对标准偏差为3.2%~7.2%。

渔业环境沉积物中硫丹及其代谢物残留的气相色谱分析

建立了渔业环境沉积物中硫丹及其代谢物硫丹硫酸酯残留量的气相色谱分析方法。样品以正已烷/丙酮(1∶1,V/V)提取、铜粉除去硫化物、石墨化碳黑-佛罗里硅土复合固相萃取柱净化、二氯甲烷/正已烷(3∶7,V/V)洗脱,用电子捕获-气相色谱(GC-ECD)测定,外标法定量。硫丹各组分在0.001～0.2μg/mL浓度范围内线性相关系良好(r≥0.9989);1、10、20μg/kg添加浓度的回收率在76.3%～107%之间,相对标准偏差(RSD)为2.31%～11.8%;α-硫丹、β-硫丹、硫丹硫酸酯的检出限(LOD)分别为0.03、0.04、0.05μg/kg(干重),最低定量限(LOQ)均为1μg/kg(干重)。适用于渔业环境硫丹污染的监测。

连云港某县农田土壤中硫丹残留调查及特征研究

对江苏省连云港市某县农田进行了土壤硫丹残留水平调查和特征研究。12个表层土样的微波萃取-气相色谱/质谱法检测结果表明,α-硫丹、β-硫丹与硫丹硫酸酯的质量比范围分别为0.61～20.02μg/kg,0.59～2.75μg/kg和0.71～5.39μg/kg,均值分别为3.85μg/kg,1.44μg/kg和2.32μg/kg,与国内外有关研究区域相比,该农田土壤中α-硫丹的残留量较高,β-硫丹与硫丹硫酸则相对较低或持平;有2个点位可能存在近期硫丹污染来源,其他多数点位的硫丹已降解为毒性相当、残效期更长的硫丹硫酸酯。总体而言,该农田的潜在生态风险值得关注。

气相色谱/负离子化学电离质谱法测定土壤中硫丹及其代谢物

采用气相色谱/负离子化学电离质谱法测定土壤中的硫丹及其代谢物.外标法定量,α-硫丹、β-硫丹及硫丹硫酸酯在0.200～10.0μg/L范围内线性良好,方法检出限分别为0.02、0.02及0.03μg/kg,空白加标平行测定的RSD为3.6%～4.3%,土壤样品加标回收率为83.6%～86.4%.本方法定性定量准确,适用于土壤中硫丹的测定.

气相色谱/负离子化学电离质谱法测定地表水中硫丹及其代谢物

采用气相色谱/负离子化学电离质谱法测定地表水中的硫丹及其代谢物,用正己烷提取,外标法定量。α-硫丹、β-硫丹及硫丹硫酸酯在0.200μg/L～10.0μg/L范围内线性良好,方法检出限分别为0.010μg/L、0.008μg/L及0.010μg/L,空白加标平行测定的RSD为3.9%～4.8%,地表水样品加标回收率为85.5%～93.8%。