固相微萃取-气相色谱-质谱法测定水中痕量有机磷和阿特拉津农药

采用PA萃取纤维吸附水中敌敌畏、乐果、内吸磷、甲基对硫磷、对硫磷、马拉硫磷等6种有机磷和阿特拉津农药,在气相色谱-质谱仪进样口热解吸后进行检测.筛选比较了几种萃取纤维,优化了萃取方式、萃取时间、离子强度、pH、解吸温度和解吸时间等萃取条件.方法适用于多类型水体中6种有机磷和阿特拉津农药的分析.     

固相萃取-高效液相色谱法测定水中呋喃丹、甲萘威和阿特拉津

采用固相萃取-高效液相色谱(SPE - HPLC)二极管阵列检测器同时测定水中呋喃丹、甲萘威和阿特拉津,以甲醇-水为流动相,采用梯度洗脱方式,选择220 nm为检测波长,二氯甲烷为洗脱剂.呋喃丹在0.200 mg/L ～5.00 mg/L、甲萘威和阿特拉津在0.020 mg/L～5.00 mg/L范围内线性良好,检出限...     

固相萃取—高效液相色谱法测定水中阿特拉津和2种邻苯二甲酸酯

采用固相萃取法对水样进行提取富集,液相色谱法测定水中2种邻苯二甲酸酯类和阿特拉津有机污染物,并对方法进行了探索、优化和验证。在固相萃取过程中,研究了水体p H、洗脱液组份对邻苯二甲酸酯和阿特拉津萃取回收率的影响,解决了邻苯二甲酸酯和阿特拉津回收率不高的问题。在空白水加标实验中,邻苯二甲酸酯的回收率为89.3%~92.2%,阿特拉津回收率为88.9%,获得了较高的回收率及测定精度。除此之外,还对地表水进行了加标回收实验,结果符合要求。     

水中阿特拉津测定的干扰消除研究

建立了使用硅胶净化小柱净化、氮磷检测器检测水中阿特拉津的方法。结果表明,经过硅胶柱净化后的生活污水,基本消除基质干扰。采用具有氮磷检测器的气相色谱仪检测阿特拉津,其质量浓度在0.10～2.0 mg/L范围内线性良好,相关系数R2=0.999,方法检出限为0.2μg/L,测定下限为0.8μg/L。空白样品加标回收率为90.0%～93.5%,实际样品加标回收率为88.5%～90.3%,相对标准偏差均10%。该方法简单、快速、准确,可以消除阿特拉津测试中基质和同系物的干扰。     

液液萃取-高效液相色谱法同时测定水中甲萘威和阿特拉津

用二氯甲烷萃取水中的甲萘威和阿特拉津，经旋转蒸发和氮吹富集浓缩后，采用高效液相色谱二极管阵列检测器在222 nm波长下测定。甲萘威和阿特拉津在0.100 mg/L～5.00 mg/L范围内线性良好，检出限分别为0.031 μg/L和0.027 μg/L，空白水样加标平均回收率为78.5%～91.7%，平行测定3次的RSD＜5%。     

海南饮用水源地水体中阿特拉津健康风险评价

采用全自动固相萃取-超高压液相色谱-串联质谱法(UPLC-MS-MS)测定海南饮用水源地原水中阿特拉津的含量。结果表明,在22个监测点位中,阿特拉津的检出率达到69.7%,其检出浓度为未检出~74.8 ng/L,浓度值均低于《地表水环境质量标准》(GB 3838—2002)中阿特拉津的标准限值。采用USEPA推荐的健康风险评价方法,对海南饮用水源地原水中阿特拉津通过饮用水和皮肤接触途径引起的健康风险进行了初步评价,阿特拉津通过饮用水和洗浴途径引起的非致癌总风险指数、致癌总风险指数分别为0~7.1×10-5和0~5.7×10-7,均在USEPA的建议值内,初步认为海南饮用水源地原水中的阿特拉津不会对人体产生明显的健康危害。     

气相色谱法测定水中的阿特拉津

以《水和废水监测分析方法》(第四版)提供的测定方法为基础,通过对色谱条件和预处理两方面的改进,采用带氮磷检测器的毛细管气相色谱仪测定水中的阿特拉津的含量,具有较好的精密度和准确度。     

胶束强化超滤法处理含酚水的实验探讨

胶束强化超滤是一种向溶液中加入表面活性剂而使污水得到净化的方法．溶液中表面活性剂的浓度必须在临界胶束浓度以上时，表面活性剂单体才开始聚集成胶团，并且形成的胶团粒径要大于超滤膜的最大孔径．让表面活性剂胶团化最重要的原因是它具有增溶作用，可以增溶一定量的溶质．     

UPLC-MS/MS法同时测定水中甲萘威、呋喃丹和阿特拉津

水样经聚四氟乙烯滤头过滤,直接用超高效液相色谱-三重四极杆串联质谱(UPLC-MS/MS)同时测定甲萘威、呋喃丹和阿特拉津。通过试验考察不同材质滤头和各仪器条件对测定的影响,并确定最佳分析条件,使该方法在0.01μg/L~10.0μg/L范围内线性良好。甲萘威、呋喃丹和阿特拉津的方法检出限分别为6.1 ng/L、2.8 ng/L、3.1 ng/L,空白水样的3个质量浓度加标回收率在96.4%~110%之间。该方法用于测定实际水源水及饮用水中的甲萘威、呋喃丹和阿特拉津,结果均未检出,实际水样平均加标回收率为81.4%~97.2%。     

望虞河西岸九里河中四种除草剂的污染现状

基于气相色谱-质谱联用(GC-MS)法结合固相萃取(SPE)前处理技术,建立了水中4种除草剂氯草定、阿特拉津、乙草胺和异丙甲草胺残留的分析方法,于2018年春(4、5月)、秋(9、10月)和冬(1、3月)季对太湖流域望虞河西岸九里河水体中4种除草剂的污染现状进行调查分析。结果表明,4种除草剂的加标回收率为71. 2%～108%,RSD均10%,方法检出限为3. 5～6. 0 ng/L。九里河水体中氯草定、阿特拉津、乙草胺和异丙甲草胺4种除草剂质量浓度分别为未检出～0. 025 7,0. 019 1～1. 19,未检出～0. 026 0和未检出～0. 094 3μg/L。4种除草剂中阿特拉津最高值接近《地表水环境质量标准》(GB 3838—2002)限值,其他3种其值较低,氯草定首次在太湖流域水体中检出。     

Spectrophotometric determination of anionic surfactants: optimization by response surface methodology and application to Algiers bay wastewater

A simple analytical method for quantitative determination of an anionic surfactant in aqueous solutions without liquid-liquid extraction is described. The method is based on the formation of a green-colored ion associate between sodium dodecylbenzenesulfonate (SDBS) and cationic dye, Brilliant Green (BG) in acidic medium. Spectral changes of the dye by addition of SDBS are studied by visible spectrophotometry at maximum wave length of 627 nm. The interactions and micellar properties of SDBS and cationic dye are also investigated using surface tension method. The pH, the molar ratio ([BG]/[SDBS]), and the shaking time of the solutions are considered as the main parameters which affect the formation of the ion pair. Determination of AS in distilled water gives a significant detection limit up to 3?×?10^?6?M. The response surface methodology (RSM) is applied to study the absorbance. A Box-Behnken is a model designed to the establishment of responses given by parameters with great probability. This model is set up by using the three main parameters at three levels. Analysis of variance shows that only two parameters affect the absorbance of the ion pair. The statistical results obtained are interesting and give us real possibility to reach optimum conditions for the formation of the ion pair. As the proposed method is free from interferences from major constituents of water, it has been successfully applied to the determination of anionic surfactant contents in wastewaters samples collected from Algiers bay.     

Determination of atrazine in surface waters by combination of POCIS passive sampling and ELISA detection

Polar organic compound integrative samplers (POCIS) in combination with instrumental techniques such as LC-MS-MS were previously used to monitor environmental pollutants but the performance of alternative immunochemical methods such as ELISA (enzyme-linked immunosorbent assay) has been explored less. In the present study, POCIS technology was applied to surface water sampling in the Czech Republic, and ELISA was used as a detection technique for the herbicide atrazine. In the first study, 28 samples from streams around small municipal waste water treatment plants (WWTPs) were collected using two different devices (POCISpest and POCISpharm) over the course of 21 days. Elevated atrazine concentrations (up to 25 ng per POCIS) were found in samples down-stream of WWTPs. This observation was also confirmed in another two year study (4 sampling periods) investigating 7 river sites around a major city of Brno as well as the inlet and outlet of the city's WWTP. High atrazine levels were systematically determined at the outlet from the WWTPs (120-605 ng per POCIS). A decreasing trend in the atrazine concentrations in rivers around the city of Brno has been observed, with the highest levels observed within the first sampling period in spring 2007 (100-600 ng per POCIS, with an extreme value of 2760 ng per POCIS). Results of the atrazine ELISA were closely correlated with LC-MS/MS, which confirmed good applicability of ELISA as a cost-effective screening tool.     

共振光散射技术测定地表水中阴离子表面活性剂

用共振光散射(RLS)技术研究了以阳离子染料维多利亚蓝B(VBB)为探针,灵敏快速测定水体中阴离子表面活性剂的新方法.在pH3.0的Britton Robinson(BR)缓冲介质中,VBB与阴离子表面活性剂十二烷基苯磺酸钠(SDBS)相互作用,形成离子缔合物,产生强烈的RLS增强效应,RLS强度的增值与SDBS的浓度成正比.据此提出了测定水体中阴离子表面活性剂的新方法.方法检出限0.021mg/L,线性范围0.10～2.40mg/L,相关系数r=0.998.不需萃取和分离,使用普通的荧光分光光度计,简单、快速、灵敏.已用于地表水中实际水样的测定,测定的结果和回收率满意.     

Atrazine Transport Within a Coastal Zone in Southeastern Puerto Rico: a Sensitivity Analysis of an Agricultural Field Model and Riparian Zone Management Model

Agrichemical runoff from farmland may adversely impact coastal water quality. Two models, the Agricultural Policy/Environmental eXtender (APEX) and the Riparian Ecosystem Management Model (REMM), were used to evaluate the movement of the herbicide atrazine to the Jobos Bay National Estuarine Research Reserve from adjacent fields. The reserve is located on Puerto Rico’s southeast coast. Edge-of-field atrazine outputs simulated with the APEX were routed through a grass-forest buffer using the REMM. Atrazine DT₅₀ (half-life) values measured in both field and buffer soils indicated that accelerated degradation conditions had developed in the field soil due to repeated atrazine application. APEX simulations examined both the measured field and buffer soil atrazine DT₅₀ and the model’s default value. The use of the measured field soil atrazine degradation rate in the APEX resulted in 33 % lower atrazine transport from the field. REMM simulations indicated that the buffer system had the potential to reduce dissolved atrazine transport in surface runoff by 77 % during non-tropical storm events by increasing infiltration, slowing transport, and increasing time for pesticide degradation. During a large runoff event due to a tropical storm that occurred close to the time of an atrazine application, the REMM simulated only a 37 % reduction in atrazine transport. The results indicate that large storm events soon after herbicide application likely dominate herbicide transport to coastal waters in the region. These results agree with water quality measurements in the reserve. This study demonstrated the sensitivity of these models to variations in DT₅₀ values in evaluating atrazine fate and transport in the region and emphasizes that the use of measured DT₅₀ values can improve model accuracy.     

Quantification of triazine herbicides in soil by microwave-assisted extraction and high-performance liquid chromatography

A method for the determination of herbicides residues, triazine (atrazine, metribuzin, ametryn, and terbutryn), in soil samples with high-performance liquid chromatography (HPLC)?CUV detection is described. The proposed method is based on microwave-assisted extraction (MAE) of soil samples for 4 min at 80% of 850-W magnetron outputs in the presence of mixture of solvents (methanol/acetonitrile/ethylacetate). Related important factors influencing the MAE efficiency, such as the solvent type and volume, irradiation energy, and time, were optimized in detail. Calibration curve ranges established using HPLC for metribuzin, atrazine, ametryn, and terbutryn are 1.0?C19.0, 0.9?C18.0, 0.6?C11.0, and 0.7?C11.0 µg mL^???1, respectively. The limits of detection of metribuzin, atrazine, ametryn, and terbutryn are 0.30, 0.24, 0.16, and 0.20 µg mL^???1 while limits of quantification are 1.0, 0.80, 0.50, and 0.60 µg mL^???1, respectively. A Plackett?CBurman factorial design was used as a screening method in order to select the variables that influence MAE extraction. The recoveries of the method at three different spiked levels were assessed by analyzing real soil samples and were found to be in the range of 83.33 ± 0.12?C96.33 ± 0.23 with good precision (<8%).     

高效液相方法同时测定地表水中的阿特拉津和甲萘葳

主要研究用反相高效液相色谱法同时测定水样中的阿特拉津和甲萘葳。结果表明,低浓度水样：可取500ml,加入5%的氯化钠,经一定量的二氯甲烷萃取、浓缩、甲醇定容后,上机测定;高浓度水样：可将水样过滤后直接进样测定。该方法的阿特拉津和甲萘葳检出限分别为0.006μg/L和0.036μg/L,加标回收率分别可达74.2%~11...     

土壤和沉积物样品中均三嗪类农药测定相关保存条件探究

采用加速溶剂萃取-高效液相色谱法探究土壤和沉积物中11种均三嗪类农药测定相关保存条件。结果表明,在4℃以下避光、密封,标准贮备液可保存60 d;标准曲线系列溶液可重复使用11 d;阿特拉津等6种化合物的土壤样品可保存20 d,其他化合物可保存5 d~12 d;经过冷冻干燥处理,阿特拉津等7种化合物的沉积物样品可保存8 d,其他化合物可保存12 d;土壤提取液至少可保存60 d。     

Atrazine and Alachlor Inputs to Surface and Ground Waters in Irrigated Corn Cultivation Areas of Castilla-Leon Region, Spain

The inputs of atrazine and alachlor herbicides to surface and ground waters from irrigated areas dedicated to corn cultivation in the Castilla-León (C-L) region (Spain) as related to the application of both herbicides were studied. Enzyme-linked immunosorbent assays (ELISA) were used for monitoring the atrazine and alachlor concentrations in 98 water samples taken from these areas. Seventy-nine of the samples were of ground waters and 19 were of surface waters. The concentration ranges of the herbicides detected in the study period (October 1997–October 1998) were 0.04–25.3 g L^–1 in the surface waters and 0.04–3.45 g L^–1 in the ground waters for atrazine, and 0.06–31.9 g L^–1 in the surface waters and 0.05–4.85 g L^–1 in the ground waters in the case of alachlor. The highly significant correlation observed between the concentrations of both herbicides in the surface waters (r = 0.89, p < 0.001) pointed to a parallel transport of atrazine and alachlor to these waters. A study was made of the temporal evolution of the concentrations of both herbicides, and it was found a maximum recharge of atrazine in the ground waters for April 1998 and of alachlor in October 1997 and October 1998. The temporal evolution of the concentrations of both herbicides in surface waters was parallel. The highly significant correlations observed between atrazine concentrations determined by ELISA and by HPLC (r = 0.92, p < 0.001) and between alachlor concentrations also determined by both methods (r = 0.96, p < 0.001) confirmed the usefulness of ELISA for monitoring both herbicides in an elevated number of samples. Using HPLC, the presence in some waters of the alachlor ethanesulfonate (ESA) metabolite was found at a concentration range of 0.52–4.01 g L^–1. However the interference of ESA in the determination of alachlor by ELISA was negligible. The inputs of atrazine and alachlor to waters found in this study, especially the inputs to ground waters, could pose a risk for human health considering that some waters, though sporadically, are even used for human consumption.     

New procedures for simultaneous determination of mesotrione and atrazine in water and soil. Comparison of the degradation processes of mesotrione and atrazine

A method for the determination of residues of mesotrione, atrazine and its degradation products: deethylatrazine, hydroxyatrazine, deisopropylatrazine, desethyldesisopropylatrazine in a variety of water and soil matrices has been developed. Mesotrione is a new selective herbicide for use in corn, which has been substituted for atrazine, which has been banned in European Union countries since 2007. Although atrazine has not been used for three vegetative periods, it is still detected in the environment. The analysis was conducted by means of ultra-high-pressure liquid chromatography with ultraviolet detection and liquid chromatography with diode array detection. The procedures for analyte separation from water and soil matrices were also established. The optimal conditions for solid-phase extraction (SPE) were determined. The recoveries were compared with that obtained by means of SPE. Method fortification recoveries from water samples averaged 78–97% and for soil 80–97% depending on the analyte and type of sample. The limits of detection were 0.04–0.61 μg/L for water samples and for soil samples 0.02–0.88 μg/g. The soil samples were collected in spring 2009 from three different fields with water samples being made from effluents from these fields. Samples collection was conducted in the day of mesotrione (Callisto 100SC) application and then done weekly, until the mesotrione concentration was below the limit of quantification. The results enabled the monitoring of mesotrione degradation in soil and its permeability into surface waters; simultaneously, the same studies were conducted for atrazine.