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1.
QuEChERS and solid phase extraction (SPE) methods were applied for determining four herbicides (metazachlor, oxyfluorfen, quizalofop-p-ethyl, quinmerac) and one insecticide (α(±)-cypermethrin) in runoff water, soil, sunflower and oilseed rape plant matrices. Determination was performed using gas chromatography mass spectrometry (GC-MS), whereas high-pressure liquid chromatography mass spectrometry (HPLC-MS) was used for quinmerac. In all substrates linearity was evaluated using matrix-matched calibration samples at five concentration levels (50–1000 ng L?1 for water, 5–500 μg kg?1 for soil and 2.5–500 μg kg?1 for sunflower or oilseed rape plant). Correlation coefficient was higher than 0.992 for all pesticides in all substrates. Acceptable mean recovery values were obtained for all pesticides in water (65.4–108.8%), soil (70.0–110.0%) and plant (66.1–118.6%), with intra- and inter-day RSD% below 20%. LODs were in the range of 0.250–26.6 ng L?1 for water, 0.10–1.8 μg kg?1 for soil and 0.15–2.0 μg kg?1 for plants. The methods can be efficiently applied for field dissipation studies of the pesticides in energy crop cultivations.  相似文献   

2.
Dissipation dynamics of fenoxaprop-p-ethyl (FPPE) and fenoxaprop acid (FPA) (metabolite) in rice field conditions was investigated for two consecutive seasons. FPPE dissipated rapidly in soil with average half life of 1.42–2.19 days. Dissipation followed first-order kinetics. The method was validated in terms of accuracy, linearity, specificity and precision. Linearity was in the range of 0.005–5 µg mL?1 with limit of detection as 0.002 and 0.001 µg mL?1 for fenoxaprop-p-ethyl and fenoxaprop acid, respectively. Quantitation limit in soil, grain, straw and husk were 0.005, 0.008, 0.01 and 0.01 µg g?1 for fenoxaprop-p-ethyl, and 0.005, 0.01, 0.01 and 0.01 µg g?1 for fenoxaprop acid, respectively. Recovery in soil, rice grains, straw and husk ranged from 81.60–93.40, 77.85–87.00, 75.20–84.40 and 76.00–87.20% for FPPE and 82.50–88.20, 76.25–83.00, 74.80–83.60 and 75.00–85.40% for FPA, respectively. Below detectable limit of residues of FPPE and metabolite were observed in soil, rice grain, husk and straw samples at harvest. FPPE and FPA were of short persistence under field conditions and residues were below European Union-Maximum Residue Limits in all matrices that would cause adverse effect on environment and human/animal health.  相似文献   

3.
In this study, a rapid and sensitive method was developed for determining fenamidone and propamocarb hydrochloride residues in vegetables and soil by ultra-performance liquid chromatography-tandem mass spectrometry. The dissipation dynamics of fenamidone and propamocarb hydrochloride in pepper and soil was investigated in Beijing, Henan and Shandong provinces. The target compounds were extracted with methanol and cleaned with dispersive solid phase extraction using primary secondary amine. Two pairs of precursor product ion transitions for fenamidone and propamocarb hydrochloride were measured and evaluated. Average recoveries of fenamidone in potato, tomato, cabbage, pepper and soil at three levels (10, 100 and 1000 μg kg?1) ranged from 76.91% to 107.31% with relative standard deviations (RSDs) from 2.74% to 10.87% (n = 15). The average recoveries of propamocarb hydrochloride ranged from 74.84% to 97.96% with RSDs from 2.43% to 16.16% (n = 15). The limits of detection (LODs) for fenamidone in each matrix were 0.131–0.291 μg kg?1, and the limits of quantification (LOQs) were 0.436–0.970 μg kg?1. The LODs for propamocarb hydrochloride were 0.125–0.633 μg kg?1, and the LOQs were 0.417–2.11 μg kg?1. The results also showed that the dissipation of fenamidone and propamocarb hydrochloride in pepper and soil followed first-order kinetics model more than that of bi-exponential models. The half-lives of propamocarb hydrochloride were 6.90–15.78 days in pepper and 13.56–23.02 days in soil. The half-lives of fenamidone were 7.48–11.29 days in pepper and 35.18–42.78 days in soil.  相似文献   

4.
Residue dissipation of hexaconazole and isoprothiolane in the rice field ecosystem was determined by gas chromatography coupled with electron capture detector. Hexaconazole and isoprothiolane (33% microemulsion) were applied at two dosages, 396 g a.i. ha–1 (the recommended dosage) and 594 g a.i. ha–1 (1.5 times the recommended dosage) in the experimental fields in Guizhou, Hunan and Heilongjiang provinces, China, during 2011–2012. The limits of detection and limits of quantification in brown rice were 0.006 and 0.02 mg kg–1 for hexaconazole, 0.0072 and 0.024 mg kg–1 for isoprothiolane, respectively, and they were much below the maximum residue limits (MRLs, 0.1 mg kg–1 for hexaconazole and 1.0 mg kg–1 for isoprothiolane) set by China. Average recoveries of hexaconazole in water, soil, rice plants and brown rice ranged from 77.3% to 93.8% and for isoprothiolane ranged from 78.1% to 99.9% with relative standard deviations < 10%. The results showed that during harvest, the terminal residue levels of hexaconazole and isoprothiolane in brown rice samples were well below the MRLs of China following the interval of 7 days after last application. Therefore, a dosage of 396 g a.i. ha–1 was recommended, which could be considered as safe to human beings.  相似文献   

5.
The combination formulation of fluopyram and tebuconazole is used for control of fungal diseases and post-harvest disease management of mango. Dissipation study of the fungicides on mango was carried out after giving applications of fluopyram +tebuconazole at the standard and double doses of 150 + 150 and 300 + 300 g active ingredient hectare?1 (g a.i. ha?1), respectively. Fluopyram residues on mango were 0.8 and 0.9 mg kg?1 and tebuconazole residues, 0.308 and 0.4 mg kg?1 after three and four applications at the standard dose. At double dose treatment the residue levels for fluopyram were 1.266 and 1.453 mg kg?1 and tebuconazole, 0.681 and 0.853 mg kg?1, respectively. Residue dissipation in mango fruits followed first order rate kinetics and the half-life (DT50) were 4.3–5.4 days for fluopyram and 3–3.8 days for tebuconazole. Faster dissipation of the fungicides was observed after the fourth treatment which directly correlated to higher rainfall during that period. The combined residues of fluopyram+tebuconazole reduced to below their maximum residue limits (MRLs) within 36–38 days. Dietary risk assessment on human health indicated that fluopyram and tebuconazole application to mango is unlikely to pose risk to human beings. This study gives valuable information on the judicious use of this combination formulation on mango, especially towards harvest.  相似文献   

6.
A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method for the analysis of triallate residue in wheat and soil was developed and validated. Multi-walled carbon nanotubes were used as clean-up sorbent. The residual levels and dissipation rates of triallate in wheat and soil were determined by liquid chromatography–tandem mass spectrometry. The limit of quantification was established as 0.01, 0.02 and 0.05 mg kg?1 for soil, wheat and wheat plant samples, respectively. The average recoveries of triallate ranged from 77% to 108% at fortified levels of 0.01–0.5 mg kg?1 with relative standard deviations of 3.0–8.4% (n = 5). From residue trials at three geographical experimental plots in China, the results showed that the half-lives of triallate in soils were 1.13–1.63 days. For trials applied according to the label recommendation, the final residues of triallate in wheat at harvest time were all below 0.05 mg kg?1 (the maximum residue levels of China, Japan, Korea and the US).  相似文献   

7.
彭西甜  夏虹  张仙  胡西州  彭立军  沈菁 《色谱》2016,34(4):436-441
建立了一种水稻植株、糙米、稻壳、土壤和田水中的杀螟丹气相色谱-火焰光度检测(GC-FPD)方法。样品中的杀螟丹使用稀盐酸提取,然后在碱性条件下使用氯化镍(NiCl2)将其衍生为沙蚕毒素,最后采用在线连接的支撑液液萃取(SLE)和固相萃取(SPE)进行萃取和富集。在优化好的条件下,杀螟丹在5种空白样品中低、中、高3种添加浓度的回收率为80.0%~114.4%,相对标准偏差(RSD)小于13.7%,表明所建立的方法具有良好的准确度和精密度。将所建立的方法用于大田条件下杀螟丹的残留动态分析,为建立杀螟丹的最大残留限量(MRL)提供参考,同时也可对农药施用技术的安全性进行评价。  相似文献   

8.
Persistence and dissipation of fluopicolide and propamocarb were studied on cabbage and soil as per good agricultural practices over a period of 2 years. A modified QuEChERS analytical method in conjunction with gas chromatography (GC) and GC–mass spectrometry was used for analysis of fluopicolide and its metabolite, 2,6-dichlorobenzamide, and propamocarb in cabbage and soil. The results of the method validation were satisfactory with recoveries within 74.5–100.81% and relative standard deviations 4.8–13.9% (n = 6). The limit of detection (LOD) and limit of quantification (LOQ) of both fluopicolide and 2,6-dichlorobenzamide were 0.003 µg mL?1 and 0.01 mg kg?1, respectively. The LOD and LOQ of propamocarb were 0.03 µg mL?1 and 0.1 mg kg?1, respectively. During 2013, the initial residue deposits of fluopicolide on cabbage were 0.60 and 1.48 mg kg?1 from treatments at the standard and double doses of 100 and 200 g a.i. ha?1 which dissipated with the half-life of 3.4 and 3.7 days. During 2014, the residues were 0.49 and 1.13 mg kg?1 which dissipated with the half-life of 4.2 and 5.1 days. Propamocarb residues on cabbage were 5.36 and 12.58 mg kg?1 in the first study (2013) and 4.85 and 10.26 mg kg?1 in the second study (2014) from treatments at the standard and double doses of 1000 and 2000 g a.i. ha?1, respectively. The residues dissipated with the half-life of 4–5.5 days. The preharvest interval, the time required for fluopicolide + propamocarb residues to dissipate below the maximum residue limits (notified by EU) at the standard dose, was 11.8 and 14 days during 2013 and 2014. Residue of 2,6-dichlorobenzamide was always <LOQ in cabbage. Residues of fluopicolide, 2,6-dichlorobenzamide and propamocarb were <LOQ in field soil at harvest.  相似文献   

9.
建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)测定水稻基质中阿维菌素残留量,考察了基质效应,并对实际样品进行了检测.稻田土、稻壳、糙米和稻杆经乙腈振荡提取,稻田水经乙酸乙酯液液分配提取后,用C18固相萃取小柱或弗罗里硅土柱净化,采用UPLC-MS/MS正离子扫描测定残留的阿维菌素.稻田土、稻田水和糙米的3种添加浓度(1.0,10.0和100 μg/kg或μg/L)的平均回收率为84%~107%,相对标准偏差为4.7%~13.6%.稻壳和稻杆的2档添加浓度(10.0和100 μg/kg)的平均回收率为90%和103%,相对标准偏差为8.4%~12.9%.本方法在稻田水、糙米和稻田土中的检出限为0.3μg/kg在稻壳和稻杆中检出限为3.0 μg/kg,低于欧盟和日本在稻米中制定的阿维菌素最大残留限量值.阿维菌素在2.0~100 μg/L范围内线性关系良好( r> 0.999).  相似文献   

10.
A rapid, highly sensitive, and selective method was developed for the determination of the insecticide chlorantraniliprole (CAP) in corn and soil using ultra-performance liquid chromatography?Ctandem mass spectrometry (UPLC?CMS/MS). Samples were extracted with acetonitrile, and aliquots were cleaned with solid-phase extraction cartridges. Two precursor-product ion transitions for CAP were measured and evaluated to provide maximum confidence in the results. Average recovery for soil, corn grain, and corn straw at different levels (5 or 10, 40, and 100 ??g kg?1) ranged from 74.9 to 97.5%, with intra-day relative standard deviation (RSD) values of 1.9?C11.3% and inter-day RSD values of 4.7?C10.4%. Coefficients of determination (R 2) of 0.9988 or higher were achieved for CAP in soil, corn grain, and corn straw matrix calibration curves, from 5 to 1,000 ??g L?1. The CAP limits of quantitation in soil, corn grain, and straw were determined to be 5, 10, and 10 ??g kg?1, respectively, which were much lower than the maximum residue levels established by the Environmental Protection Agency of United States. UPLC?CMS/MS was used to determine the CAP residues in real corn and soil for studies on their dissipation. The trial results showed that the half-lives of CAP changed from 12.6 to 23.1 days in soils and ranged from 4.9 to 5.4 days in corn straws in the districts of Henan and Shandong, and the average levels of CAP residues in corn grains were all <0.01 mg kg?1 with a harvest withholding period of 180 days.  相似文献   

11.
A high-performance liquid chromatography with ultraviolet (HPLC-UV) detection method after derivatisation was developed for the first time for the novel fungicide zinc thiazole residue in tobacco samples. Field trials in two different locations were conducted to investigate the dissipation and residue of zinc thiazole in tobacco leaves and soil. The average recoveries of zinc thiazole were in the range of 82.5%–93.9% with relative standard deviations (RSDs) of 1.2%–9.1%. The zinc thiazole showed a rapid dissipation rate in fresh tobacco leaves with the half-lives of 1.1–1.6 days. The terminal residues of zinc thiazole in cured tobacco leaves and soil were 2.8–28.0 mg kg?1and <0.05 mg kg?1, respectively. The results could be used to establish the maximum residue limits (MRLs) and provide guidance for the scientific use of zinc thiazole in agriculture.  相似文献   

12.
A sensitive, rapid and easy analytical method was validated for the determination of quinoid niclosamide (LDS) molluscicide in water, rice and soil using a QuEChERS extraction procedure and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection. The LDS was extracted by using acetonitrile and then cleaned up by using dispersive solid-phase extraction with florisil and C18 sorbents. The determination of the target compound was achieved in less than 3 min using an electrospray ionisation source in negative mode. The overall average recoveries for this method in water, rice and soil matrix at three fortified levels ranged from 82.54 to 99.9%, with relative standard deviations in the range of 1.51 to 4.86% (n = 5). The calculated limits of detection were lower than 0.1 µg kg?1 and quantification was 5 µg kg?1; these values were much lower than the maximum residue levels established by the Australian standard (0.01 mg kg?1). The results of the method validation confirmed that this proposed method is convenient and reliable for the determination of LDS molluscicide in water, rice and soil samples.  相似文献   

13.
A field experiment was conducted to evaluate clofentezine residue levels and dissipation trend in tangerine and soil for the safe application of clofentezine. A modified QuEChERS-HPLC-UVD method was developed to analyse clofentezine in tangerine and soil. Tangerine samples were homogenised and extracted by acetonitrile and then cleaned up with dispersive solid phase extraction (dSPE) by primary and secondary amine (PSA) and C18. Clofentezine residue was determined by high-performance liquid chromatography (HPLC) with a UV detector (UVD) at the wavelength of 268 nm. The presented method achieved the good linear relationship within the range from 0.05 to 5.0 mg kg?1 for clofentezine (R2 > 0.998). At the fortification levels of 0.05, 0.50 and 1.00 mg kg?1 in tangerine pulp, tangerine peel and soil, recoveries ranged from 75.9% to 117.7% with relative standard deviations (RSD) less than 8.2%. In the supervised field trials, the half-lives of clofentezine in tangerine and soil were approximately 11.3 and 8.6 days, respectively. At pre-harvest interval of 21 days, the residue of clofentezine in tangerine was below the maximum residue limits (MRL) (0.5 mg kg?1). Clofentezine (Water Dispersible Granule, 80%) was recommended to be sprayed twice and the recommended dosage ranged from 250 to 375 mg kg?1.  相似文献   

14.
The dissipation dynamics and final residues of flutriafol on tobacco plant and soil were studied under field conditions. The residues of flutriafol in soil, green tobacco leaves and cured tobacco leaves were extracted by ultrasound-assisted extraction, cleaned up by dispersive solid-phase extraction and detected by liquid chromatography with tandem mass spectrometry. The limits of detection of flutriafol in soil, green tobacco leaves and cured tobacco leaves were 0.006, 0.033 and 0.033 mg·kg?1, respectively. The limits of quantification of flutriafol in soil, green tobacco leaves and cured tobacco leaves were 0.02, 0.1 and 0.1 mg·kg?1, respectively. Recoveries were 72.9–102% with relative standard deviations of less than 12% in soil and tobacco matrix. For field experiments, the half-lives of flutriafol in soil and green tobacco leaves were 9.2–11.5 and 9.5–11.1 days, respectively. At harvest, the final residue levels of flutriafol in cured tobacco leaves collected 21 days after one application at the recommended dosage were below 2.0 mg/kg. The maximum residue limit maximum residue limit (MRL) for flutriafol in tobacco has not yet been established in any countries. The data could help the Chinese Government to establish the MRL of flutriafol in tobacco and provide guidance on the proper use of flutriafol.  相似文献   

15.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

16.
Two independent field trials were performed in Guizhou and Hunan, China in 2013 to investigate the dissipation and residue levels of saisentong in tobacco and soil. A novel and accurate method using high-performance liquid chromatography with diode array detection was developed and validated to determine saisentong levels in tobacco and soil. The average recovery of saisentong at fortification levels of 0.5, 2.5, 5.0 and 50.0 mg kg?1 in fresh tobacco ranged from 75.92 to 107.40% with a relative standard deviation (RSD) of 0.94 to 7.55%, that at fortification levels of 0.5, 2.0 and 5.0 mg kg?1 in tobacco powder ranged from 74.96 to 94.43% with a relative standard deviation (RSD) of 4.38 to 8.14%, and that at fortification levels of 0.1, 0.5 and 5.0 mg kg?1 in soil ranged from 86.90 to 100.0% with an RSD of 1.38 to 4.62%. The limit of detection (LOD) of saisentong was 0.15 mg?kg?1 in tobacco and 0.03 mg kg?1 in soil, and the limit of quantification (LOQ) was 0.5 mg kg?1 in tobacco and 0.1 mg kg?1 in soil, respectively. For field experiments, the half-lives of saisentong in tobacco from Guizhou and Hunan were 5.9 and 1.6 days, respectively; those in soil were 14.7 and 12.0 days, respectively. The results suggest that the saisentong dissipation curves followed the first-order kinetic. The terminal residues of saisengtong in tobacco ranged from 0.5 to 9.39 mg kg?1 at pre-harvest intervals (PHI) of 7, 14 and 21 days.  相似文献   

17.
In this study, an effective analytical method for simultaneous determination of thiamethoxam and its metabolite clothianidin in goji berry and soil was developed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The recoveries of the compounds in goji berry and soil at the levels of 0.005, 0.02, and 0.1 μg kg?1 were 84.7–98.9% and the relative standard deviations (RSDs) were 0.9–3.2%. The limits of detection (LOD) for both compounds in goji berry and soil matrices were 0.001 mg kg?1; the limits of quantification (LOQ) were 0.005 mg kg?1 for both compounds in two matrices. The dissipation and final residual experiments in 2016 with the commercial formulation of dinotefuran ? thiamethoxam 30% suspension concentrate (SC) was conducted in goji berries in northwest China (Qinghai, Gansu, Inner Mongolia, and Ningxia). Thiamethoxam was dissipated fast in goji plant ecosystem with half-lives were 1.08–1.01 and 2.04–4.25 days in goji berry and soil. The final residues of thiamethoxam were <0.005–0.382 and <0.005–1.120 mg kg?1 in goji berry and soil, respectively.  相似文献   

18.
An analytical method was developed to detect the residue of mebendazole and its metabolites (hydroxymebendazole and aminomebendazole) in the muscle of grass carp and shrimp by LC–UV detection. Mebendazole and its metabolites were extracted with water and ethyl acetate, defatted with hexane, and purified with MCX solid phase extraction column. The intra- and inter-batch precision (measured by CV%) was <9.0%. The accuracy (measured by relative error, %) was <12%. The LODs were 2.5 μg kg?1 for mebendazole and hydroxymebendazole, 5 μg kg?1 for aminomebendazole; the LOQs were 5 μg kg?1 for mebendazole and hydroxymebendazole, 10 μg kg?1 for aminomebendazole. The mean recoveries of mebendazole and its metabolites from grass carp and shrimp muscle at a concentration range of 5.0–500.0 μg kg?1 were 90.7–97.0% with relative standard deviations below 10%.  相似文献   

19.
Dissipation and residue levels of bifenthrin and chlorfenapyr in eggplant and soil under field conditions were investigated using gas chromatography coupled with an electron capture detector (GC-ECD). The mean recoveries of bifenthrin and chlorfenapyr were 85.2–104.9%, with relative standard deviations (RSDs) of 0.5–9.1%. The limit of quantification (LOQ) was 0.01 mg kg?1. Bifenthrin exhibited half-lives of 3.3 to 4.1 days in eggplant and 17.8 to 25.7 days in soil; the half-lives of chlorfenapyr were 3.5 to 3.8 days in eggplant and 21.7 to 27.7 days in soil. During harvest, the terminal residues of bifenthrin and chlorfenapyr were below 0.031 and 0.083 mg kg?1, respectively. Risk assessment for different groups of people in China was evaluated. The risk quotients (RQs) of bifenthrin and chlorfenapyr were ranged from 0.0068 to 0.0148 and from 0.0033 to 0.0072, respectively. These results may provide guidance on reasonable use of pesticides and serve as a basis for establishing maximum residue limits (MRLs) in China.  相似文献   

20.
The present study was carried out to develop an analytical method for simultaneously detecting and quantifying sulfoxaflor and its metabolites (X11721061, X11719474) in brown rice and rice straw using liquid chromatography–tandem mass spectrometry. The parent compound and its metabolites were extracted and purified using original ‘QuEChERS’ method with modification. The matrix-matched calibration curve of sulfoxaflor and its metabolites in both matrices achieved good linearity with determination coefficients (R2) ≥0.9944. The overall recoveries of sulfoxaflor at two fortification levels (rice: 0.2 and 1.0 mg/kg; rice straw: 0.4 and 2.0 mg/kg) ranged from 97.37% to 107.71% with relative standard deviations (RSDs) <5%. On the other hand, the recoveries of both metabolites (X11721061 and X11719474) at 0.1 and 0.5 mg/kg (rice) and 0.2 and 1.0 mg/kg (rice straw) were satisfactory with values ranging from 83.70 % to 112.60% with RSDs <8%. During storage at ?20°C, the analyte and its metabolites were stable for up to 87 days. The limits of quantification of 0.02 mg/kg were lower than the maximum residue limit (0.2 mg/kg) set by the Korean Ministry of Food and Drug Safety for brown rice. The method was successfully applied to paddy field treated with different programme schedules and a preharvest interval of 7 days was proposed based upon the current study. In sum, the developed method is accurate and reproducible for ensuring the reliable determination of sulfoxaflor (and its metabolites) in harvested rice grain and straw samples from the field. The residual level of parent compound does not seem to pose any hazardous effect and treated rice could be safely used for consumption.  相似文献   

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