液相色谱法检测水果蔬菜中的烟碱类农药残留

建立了果蔬样品中5种烟碱类农药(噻虫嗪、吡虫啉、啶虫脒、噻虫啉、噻虫胺)残留的液相色谱快速检测方法。样品采用乙腈提取,浓缩,水转溶后经ENVI-18固相萃取柱净化,0.02 mol/L NaOH预淋洗除去柱上中等极性干扰物,100%乙腈1 mL洗脱5种烟碱类残留,反相高效液相色谱-二极管阵列检测器检测。在黄瓜空白基质中0.1~1.0 mg/kg的加标浓度范围内,5种农药的回收率为50.8%~108.9%,相对标准偏差(RSD)小于15%;而苹果、梨、香蕉、西红柿和韭菜空白基质在0.1~1.0 mg/kg添加水平下,5种农药的回收率均大于80%,RSD小于11%。所测试的6种果蔬样品中噻虫嗪、噻虫胺、吡虫啉的检出限(LOD)为0.01~0.02 mg/kg,啶虫咪和噻虫啉的LOD为0.03~0.05 mg/kg,方法可满足水果蔬菜中烟碱类农药多残留分析的要求。     

Validation of a highly sensitive method for the determination of neonicotinoid insecticides residues in honeybees by liquid chromatography with electrospray tandem mass spectrometry

The validation of a multi-residue method for the determination of five neonicotinoid insecticides (imidacloprid, clothianidin, acetamiprid, thiacloprid and thiamethoxam) in honeybees is described. The method involves the extraction of pesticides using acetonitrile and liquid partitioning with n-hexane. One clean-up is then performed on a florisil cartridge (1?g, 6?mL) and the extract is analysed by liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS). The recovery data were obtained by spiking honeybees samples free of pesticides at two concentration levels of the various neonicotinoids. The recoveries were in the range between 93.3 and 104.0% with relative standard deviation (RSD) less than 20%. The limit of quantification (LOQ) was 0.5?ng?g^?1 (corresponding to 0.05?ng?bee^?1) for all pesticides except for acetamiprid which was 1?ng?g^?1 (corresponding to 0.1?ng?bee^?1).     

在线固相萃取-超高效液相色谱/串联质谱法测定水中新烟碱类杀虫剂

采用在线固相萃取-超高效液相色谱/串联质谱技术建立了水中啶虫脒、噻虫胺、吡虫啉、噻虫啉、噻虫嗪、呋虫胺及烯啶虫胺7种新烟碱类杀虫剂的检测方法。样品滤膜过滤后,经HLB Dierect Connect HP在线固相萃取小柱富集纯化,以ACQUITY UPLC BEH C₁₈为分析柱串联质谱进行检测,外标法定量。在线富集水样中新烟碱类物质在5.0~200 ng/L范围内线性关系良好,相关系数R²均大于0.99;检出限为0.30~2.92 ng/L,相对标准偏差均小于10%。该法可用于保障水环境安全、及时提供污染信息。     

Determination of Neonicotinoid Pesticides in Propolis with Liquid Chromatography Coupled to Tandem Mass Spectrometry

In this study, a method was developed for the determination of five neonicotinoid pesticides (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) in propolis. Two sample preparation methods were tested: solid-phase extraction and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. The identities of analytes were confirmed using liquid chromatography–tandem mass spectrometry (LC-MS/MS) in the selected reaction monitoring mode. Solid-phase extraction resulted in cleaner extracts; therefore, the SPE-LC-MS/MS method was validated according to the SANTE protocol in triplicate at two spiking levels (10 ng/g and 50 ng/g). The average recoveries of analytes ranged from 61% to 101%, except for clothianidin (10–20%). The LOD ranged from 0.2 ng/g to 4.4 ng/g, whereas the LOQ was in the range of 0.8 ng/g–14.7 ng/g. In order to compensate for the matrix effect, matrix-matched calibration was used. Good accuracy (relative error: 1.9–10.4%) and good linearity (R² > 0.991) were obtained for all compounds. The optimised method was applied to 30 samples: 18 raw propolis and 12 ethanol tinctures. Acetamiprid, imidacloprid, and thiacloprid were detectable in seven samples but were still below the LOQ. This study is the first to report the determination of several neonicotinoid residues in propolis.     

Ultrasound/microwave‐assisted solid–liquid–solid dispersive extraction with high‐performance liquid chromatography coupled to tandem mass spectrometry for the determination of neonicotinoid insecticides in Dendrobium officinale

A one‐step ultrasound/microwave‐assisted solid–liquid–solid dispersive extraction procedure was used for the simultaneous determination of eight neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid, thiacloprid, imidaclothiz) in dried Dendrobium officinale by liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. The samples were quickly extracted by acetonitrile and cleaned up by the mixed dispersing sorbents including primary secondary amine, C₁₈, and carbon‐GCB. Parameters that could influence the ultrasound/microwave‐assisted extraction efficiency such as microwave irradiation power, ultrasound irradiation power, temperature, and solvent were investigated. Recovery studies were performing well (70.4–113.7%) at three examined spiking levels (10, 50, and 100 μg/kg). Meanwhile, the limits of quantification for the neonicotinoids ranged from 0.87 to 1.92 μg/kg. The method showed good linearity in the concentration range of 1–100 μg/L with correlation coefficients >0.99. This quick and useful analytical method could provide a basis for monitoring neonicotinoid insecticide residues in herbs.     

Liquid chromatography–tandem mass spectrometry analysis of neonicotinoid pesticides and 6-chloronicotinic acid in environmental water with direct aqueous injection

An efficient, high throughput and cost-effective direct aqueous injection approach for the analysis of neonicotinoid pesticides and a common metabolite in environmental water has been described here. The method determines eight neonicotinoid pesticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitenpyram, thiacloprid, thiamethoxam) and 6-chloronicotinic acid (a common metabolite of the first generation neonicotinoids, acetamiprid, imidacloprid, nitenpyram and thiacloprid) without any sample enrichment/cleanup steps. The method detection limits are 2–8 ng/L for the neonicotinoids and 93 ng/L for 6-chloronicotinic acid. The performance of the QTRAP^®5500 mass spectrometer was compared against a 4000QTRAP^®, and a QTRAP^®6500, to provide insights for future method transfer among different generations of instrumentations. Critical mass spectrometric parameters such as collision energy were quite consistent among the three instruments evaluated. However, increased chemical background levels for some target compounds on the more sensitive instruments were observed. The application of differential ion mobility spectrometry combined with tandem mass spectrometry was demonstrated to have great potential in reducing chemical background and/or isobaric interferences inherited in sample matrices. This ISO 17025 accredited method was employed to quantitate neonicotinoids in Ontario stream water samples. Good correlation for analytical results of this direct aqueous injection approach and a previously published solid phase extraction approach warrant high confidence in data quality.     

An Electrochemical Sensor Based on Electropolymerization of ß‐Cyclodextrin and Reduced Graphene Oxide on a Glassy Carbon Electrode for Determination of Neonicotinoids

An electrochemical sensor of glassy carbon electrode modified with reduced graphene oxide and β‐cyclodextrin (GCE/rGO/β‐CD) was developed as an effective alternative in the determination of neonicotinoid insecticides, imidacloprid, clothianidin and thiamethoxam, in honey samples. The peak current variation obtained with the proposed sensor was higher compared to the bare GCE in all the analytes. In the determination of imidacloprid the response increased by 1300 %, clothianidin by 670 % and thiametoxam by 630 %. In addition, the optimization of the experimental conditions provided the construction of a sensor with greater sensitivity. The study of interferers showed that inorganic ions (Ca²⁺, Mg²⁺, Fe²⁺, K⁺, Na⁺, e NH₄⁺) and other insecticides (acetamiprid and dinotefuran) did not influence the reduction of imidacloprid, clothianidin and thiamethoxam. The determination of imidacloprid, clothianidin and thiamethoxam in honey samples exhibited recovery values within the EPA range (between 107.75 and 116 %). In conclusion, the developed sensor GCE/rGO/β‐CD proved to be an effective alternative in the determination of neonicotinoid insecticides in honey samples.     

Determination of neonicotinoid pesticides residues in agricultural samples by solid-phase extraction combined with liquid chromatography-tandem mass spectrometry

This work reports a new sensitive multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection, confirmation and quantification of six neonicotinoid pesticides (dinotefuran, thiamethoxam, clothiandin, imidacloprid, acetamiprid and thiacloprid) in agricultural samples (chestnut, shallot, ginger and tea). Activated carbon and HLB solid-phase extraction cartridges were used for cleaning up the extracts. Analysis is performed by LC-MS/MS operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. Quantification was carried by the internal standard method with D(4)-labeled imidacloprid. The method showed excellent linearity (R(2)≥0.9991) and precision (relative standard deviation, RSD≤8.6%) for all compounds. Limits of quantification (LOQs) were 0.01 mg kg(-1) for chestnut, shallot, ginger sample and 0.02 mg kg(-1) for tea sample. The average recoveries, measured at three concentrations levels (0.01 mg kg(-1), 0.02 mg kg(-1) and 0.1 mg kg(-1) for chestnut, shallot, ginger sample, 0.02 mg kg(-1), 0.04 mg kg(-1) and 0.2 mg kg(-1) for tea sample), were in the range 82.1-108.5%. The method was satisfactorily validated for the analysis of 150 agricultural samples (chestnut, shallot, ginger and tea). Imidacloprid and acetamiprid were detected at concentration levels ranging from 0.05 to 3.6 mg kg(-1).     

Determination of neonicotinoid insecticides in environmental samples by micellar electrokinetic chromatography using solid‐phase treatments

A sensitive and reliable method based on MEKC has been developed and validated for trace determination of neonicotinoid insecticides (thiamethoxam, acetamiprid, and imidacloprid) and the metabolite 6‐chloronicotinic acid in water and soil matrices. Optimum separation of the neonicotinoid insecticides was obtained on a 58 cm long capillary (75 μm id) using as the running electrolyte 40 mM SDS, 5 mM borate (pH 10.4), and 5% (v/v) methanol at a temperature of 25°C, a voltage of 25 kV and with hydrodynamic injection (10 s). The analysis time was less than 7 min. Prior to MEKC determination, the samples were purified and enriched by carrying out extraction‐preconcentration steps. For aqueous samples, off‐line SPE with a sorptive material such as Strata‐X (polymeric hydrophobic sorbent) and octadecylsilane (C₁₈) was carried out to clean up and preconcentrate the insecticides. However, for soil samples, matrix solid‐phase dispersion (MSPD) was applied with C₁₈ used as the dispersant. Good linearity, accuracy, and precision were obtained and the detection limits were in the range between 0.01 and 0.07 μg mL^?1 for river water and 0.17 and 0.37 μg g^?1 for soil samples. Recovery levels reached greater than 92% for all of the assayed neonicotinoids in river water samples with Strata‐X. In soil matrices, the best recoveries (63–99%) were obtained with MSPD.     

Analysis of nicotinoid insecticides residues in honey by solid matrix partition clean-up and liquid chromatography-electrospray mass spectrometry

An analytical method for the routine simultaneous determination of four nicotinoid insecticides (acetamiprid, imidacloprid, thiacloprid and thiamethoxam) in commercial multifloral honey was developed. Fortified honey samples, dissolved in water, were cleaned up through Extrelut NT20 column and, finally, insecticides were eluted with dichloromethane. The eluate was evaporated, the residue redissolved in methanol and then analyzed by LC-ESI(+)-MS. Average recoveries of the four analytes were in the range of 76% and 99% at both spiking levels 0.1 and 1.0 mg kg(-1). Relative standard deviations (RSDs) were less than 10% for all of the recovery tests. The detection limits (LODs) of the method ranged from 0.01 to 0.1 mg kg(-1) for the different insecticides studied. The developed method is linear over the range assayed, 0.5-5.0 microg mL(-1), with linear correlation coefficients higher than 0.9993.     

Simultaneous determination of residues in pollen and high-fructose corn syrup from eight neonicotinoid insecticides by liquid chromatography–tandem mass spectrometry

The neonicotinoids have recently been identified as a potential contributing factor to the sudden decline in adult honeybee population, commonly known as colony collapse disorder (CCD). To protect the health of honeybees and other pollinators, a new, simple, and sensitive liquid chromatography-electrospray ionization mass spectrometry method was developed and validated for simultaneous determination of eight neonicotinoids, including acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitenpyram, thiacloprid, and thiamethoxam, in pollen and high-fructose corn syrup (HFCS). In this method, eight neonicotinoids, along with their isotope-labeled internal standards, were extracted from 2 g of pollen or 5 g of HFCS using an optimized quick, easy, cheap, effective, rugged, and safe extraction procedure. The method limits of detection in pollen and HFCS matrices were 0.03 ng/g for acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, and thiamethoxam and ranged between 0.03 and 0.1 ng/g for nitenpyram and flonicamid. The precision and accuracy were well within the acceptable 20 % range. Selectivity, linearity, lower limit of quantitation, matrix effect, recovery, and stability in autosampler were also evaluated during validation. This validated method has been used successfully in analyzing a set of pollen and HFCS samples collected for evaluating potential honeybee exposure to neonicotinoids.     

Determination of neonicotinoid insecticides residues in eels using subcritical water extraction and ultra-performance liquid chromatography–tandem mass spectrometry

A rapid, sensitive, and environmental-friendly multi-residue method has been developed for the simultaneous determination of seven neonicotinoid insecticides (dinotefuran, nitenpyram, thiamethoxam, imidacloprid, clothianidin, acetamiprid, and thiacloprid) residues in eel samples. Subcritical water extraction was investigated as a novel and alternative technology for the extraction of neonicotinoids from eel matrices and the results were compared with the conventional ultrasonic and shaking extraction. The target compounds were identified and quantitatively determined by ultra-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC–MS/MS) operated in multiple reaction monitoring mode. Under the current optimized chromatographic conditions, each LC run was completed in 5 min. Average recoveries of the seven analytes from fortified samples ranged between 84.6% and 102.0%, with relative standard deviations (RSD) lower than 10.8%. The limits of detection (LODs) and quantification (LOQs) for neonicotinoids were in the ranges of 0.12–0.36 μg kg⁻¹ and 0.42–1.12 μg kg⁻¹, respectively. The proposed method is fast, sensitive, easy to perform, water-based thus more environmentally acceptable, making it applicable for high-throughput monitoring of insecticides residues in aquatic products.     

One‐pot synthesis of magnetic zeolitic imidazolate framework/grapheme oxide composites for the extraction of neonicotinoid insecticides from environmental water samples

Magnetic zeolitic imidazolate framework 67/graphene oxide composites were synthesized by one‐pot method at room temperature for the first time. Electrostatic interactions between positively charged metal ions and both negatively charged graphene oxide and Fe₃O₄ nanoparticles were expected to chemically stabilize magnetic composites to generate homogeneous magnetic products. The additional amount of graphene oxide and stirring time of graphene oxide, Co²⁺, and Fe₃O₄ solution were investigated. The zeolitic imidazolate framework 67 and Fe₃O₄ nanoparticles were uniformly attached on the surface of graphene oxide. The composites were applied to magnetic solid‐phase extraction of five neonicotinoid insecticides in environmental water samples. The main experimental parameters such as amount of added magnetic composites, extraction pH, ionic strength, and desorption solvent were optimized to increase the capacity of adsorbing neonicotinoid insecticides. The results show limits of detection at signal‐to‐noise ratio of 3 were 0.06–1.0 ng/mL under optimal conditions. All analytes exhibited good linearity with correlation coefficients of higher than 0.9915. The relative standard deviations for five neonicotinoid insecticides in environmental samples ranged from 1.8 to 16.5%, and good recoveries from 83.5 to 117.0% were obtained, indicating that magnetic zeolitic imidazolate framework 67/graphene oxide composites were feasible for analysis of trace analytes in environmental water samples.     

Determination of neonicotinoid insecticides in natural waters by high-resolution time-of-flight mass spectrometry with direct electrospray ionization of samples

A possibility of the direct electrospray ionization of seven neonicotinoids (acetamiprid, dinotefuran, imidacloprid, chlothianidin, nitenpyram, thiacloprid, and thiamethoxam) and their determination in natural waters by quadrupol high-resolution time-of-flight mass spectrometry is shown. A considerable matrix effect in the determination of neonicotinoids in natural waters was found. It was eliminated by the tenfold dilution of test samples with deionized water. Two versions of the determination of neonicotinoids in natural water samples are proposed: the method of standard additions and the method of calibration graph constructed for solutions in deionized water in the analysis of samples tenfold diluted with deionized water. The analytical ranges for neonicotinoids are 1–50 ng/mL. The relative standard deviation of the results of analysis does not exceed 12%; the duration of analysis is 10–15 min.     

Application of solid-phase extraction and liquid chromatography-mass spectrometry to the determination of neonicotinoid pesticide residues in fruit and vegetables

A rapid and simple method for simultaneous analysis of four neonicotinoid insecticides including acetamiprid, imidacloprid, thiacloprid and thiamethoxam in fruit and vegetable matrices has been developed. For instance, ready-to-use cartridges filled with a macroporous diatomaceous material were used to extract in a single step insecticide residues with dichloromethane from aqueous-acetone extracts of fruits and vegetables. The eluate was evaporated, the residue redissolved with methanol and then analyzed by liquid chromatography-mass spectrometry in the electrospray ionization (ESI) positive mode. Average recoveries of the four pesticides were between 74.5 and 105% at both spiking levels 0.1 and 1.0 mg kg(-1) in peach, pear, courgette, celery and apricot. Relative standard deviations (RSDs) were less than 10% for all of the recovery tests. The calculated limits of quantitation (LOQs) (0.1-0.5 mg kg(-1)) were equal or lower then the maximum residue limits (MRLs) established by European legislation (0.1-0.5 mg kg(-1)). The proposed method is fast, easy to perform and could be utilized for monitoring of pesticides residues.     

Trace-level determination of pyrethroid,neonicotinoid and carboxamide pesticides in beeswax using dispersive solid-phase extraction followed by ultra-high-performance liquid chromatography-tandem mass spectrometry

The aim of the work was to develop an analytical procedure able to quantify traces of 13 neonicotinoids and pyrethroids as well as carboxamide in beeswax at low levels (ng g^?1) to evaluate the contamination. For this purpose, an efficient sample preparation procedure was developed based on solid–liquid extraction using dispersive diatomaceous earth and acetonitrile. This step was followed by a selective and sensitive analysis based on ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (ESI-MS/MS). This analytical procedure was validated based on International Conference on Harmonization guidelines. The limits of quantification ranged from 1 ng g^?1 (thiamethoxam, clothianidin, imidacloprid, acetamiprid, thiacloprid and boscalid) to 40 ng g^?1 (lambda-cyhalothrin). The method was then successfully applied to 60 samples of beeswax collected in several areas of France. The presence of thiacloprid, boscalid, imidacloprid and deltamethrin in beeswax was confirmed. The most frequently quantified pesticide was boscalid.     

Graphene oxide as a micro‐solid‐phase extraction sorbent for the enrichment of parabens from water and vinegar samples

A simple hydrophilic polyamide organic membrane protected micro‐solid‐phase extraction method with graphene oxide as the sorbent was developed for the enrichment of some parabens from water and vinegar samples prior to gas chromatography with mass spectrometry detection. The main experimental parameters affecting the extraction efficiencies, such as the type and amount of the sorbent, extraction time, stirring rate, salt addition, sample solution pH and desorption conditions, were investigated. Under the optimized experimental conditions, the method showed a good linearity in the range of 0.1–100.0 ng/mL for water samples and 0.5–100.0 ng/mL for vinegar samples, with the correlation coefficients varying from 0.9978 to 0.9997. The limits of detection (S/N = 3) of the method were in the range of 0.005–0.010 ng/mL for water samples and 0.01–0.05 ng/mL for vinegar samples, respectively. The recoveries of the method for the analytes at spiking levels of 5.0 and 70.0 ng/mL were between 84.6 and 106.4% with the relative standard deviations varying from 4.2 to 9.5%. The results indicated that the developed method could be a practical approach for the determination of paraben residues in water and vinegar samples.     

Degradation of the Neonicotinoid Pesticides in the Atmospheric Pressure Ionization Source

During the analysis of neonicotinoid pesticide standards (thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid) by mass spectrometry, the degradation of these pesticides (M-C=N-R is degraded into M-C=O, M is the skeleton moiety, and R is NO₂ or CN) was observed in the atmospheric pressure ionization interfaces (ESI and APCI). In APCI, the degradation of all the five neonicotinoid pesticides studied took place, and the primary mechanism was in-source ion/molecule reaction, in which a molecule of water (confirmed by use of H₂ ¹⁸O) attacked the carbon of the imine group accompanying with loss of NH₂R (R=NO₂, CN). For the nitroguanidine neonicotinoid pesticides (R=NO₂, including thiamethoxam, clothianidin, and imidacloprid), higher auxiliary gas heater temperature also contributed to their degradation in APCI due to in-source pyrolysis. The degradation of the five neonicotinoid pesticides studied in ESI was not significant. In ESI, only the nitroguanidine neonicotinoid pesticides could generate the degradation products through in-source fragmentation mechanism. The degradation of cyanoamidine neonicotinoid pesticides (R=CN, including acetamiprid and thiacloprid) in ESI was not observed. The degradation of neonicotinoid pesticides in the ion source of mass spectrometer renders some adverse consequences, such as difficulty interpreting the full-scan mass spectrum, reducing the sensitivity and accuracy of quantitative analysis, and misleading whether these pesticides have degraded in the real samples. Therefore, a clear understanding of these unusual degradation reactions should facilitate the analysis of neonicotinoid pesticides by atmospheric pressure ionization mass spectrometry.

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Graphical Abstract

     

β‐Cyclodextrin polymer@Fe3O4 based magnetic solid‐phase extraction coupled with HPLC for the determination of benzoylurea insecticides from honey,tomato, and environmental water samples

In this work, a magnetic β‐cyclodextrin polymer was successfully prepared and used as an adsorbent for the magnetic solid‐phase extraction of six benzoylurea insecticides (diflubenzuron, triflumuron, hexaflumuron, teflubenzuron, flufenoxuron, and chlorfluazuron) from honey, tomato, and environmental water samples. The influence of the main experimental conditions on the extraction was studied. Under the optimized conditions, the β‐cyclodextrin polymer@Fe₃O₄ showed an excellent extraction performance for the benzoylurea insecticides. A good linearity was obtained for the analytes in the range of 3.0–800 ng/g for honey samples, 0.3–160 ng/g for tomato samples, and 0.1–80.0 ng/mL for water samples, with the correlation coefficients above 0.9998. Satisfactory repeatabilities were achieved, with the relative standard deviations less than 5.7%. The limits of detection (S/N = 3) of the method for the benzoylurea insecticides were 0.2–0.8 ng/g for honey samples, 0.04–0.10 ng/g for tomato samples, and 0.02–0.05 ng /mL for water samples. The method was successfully used for the determination of the six benzoylurea insecticides residues in honey, tomato, and environmental water samples with a satisfactory result.     

Sensitive determination of thiamethoxam, imidacloprid and acetamiprid in environmental water samples with solid-phase extraction packed with multiwalled carbon nanotubes prior to high-performance liquid chromatography

This paper describes a novel method for sensitive determination of thiamethoxam, imidacloprid and acetamiprid based on solid-phase extraction with multiwalled carbon nanotubes as the packed materials. Factors that maybe influence the enrichment efficiency, such as sample flow rate, sample pH, and sample volume, were investigated in detail. Under the optimized conditions, the detection limits of thiamethoxam, imidacloprid and acetamiprid were 6.1, 5.4 and 6.7 ng L⁻¹, respectively. The experimental results indicated that there was good linearity (R ²>0.9993) over the range of 0.08~100 ng mL⁻¹ and good reproducibility with the relative standard deviations over the range of 0.7~1.1% (n=6). The proposed method has been applied to the analysis of real-world water samples, and satisfactory achievements were obtained. The average spiked recoveries were in the range of 87.5~109.8%. All the results indicated that the proposed method could be used for the simultaneous determination of the three pesticides in environmental water samples at trace levels.