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1.
As chlorpyrifos is used globally to control pests in sugarcane fields, analysis of its residues on food crops is essential to assess product safety for humans. In this study, chlorpyrifos content in sugarcane plants, soil and juice was determined using a gas chromatography with an electron capture detector. The limit of quantification was 0.01 mg/kg for plant and soil, and 0.01 mg/L for juice. The degradation and residual risk in sugarcane fields after applying chlorpyrifos to two sample sites (Changsha and Danzhou, China) were assessed. Chlorpyrifos concentrations in plants and soil decreased rapidly over time, reaching a degradation rate ranging from 98.82 to 99.25% on day 35. The half‐life of chlorpyrifos in both plants and soil was only 5.97–6.12 days. Regardless of application dosage (standard or high) at a pre‐harvest interval of 60 days, chlorpyrifos was undetectable in the harvested sugarcane. Risk assessment indicated that chlorpyrifos residue in sugarcane did not pose a health risk to humans.  相似文献   

2.
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   

3.
A modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the simultaneous determination of spirotetramat and its four metabolite residues in citrus, peel, pulp and soil was developed and validated by liquid chromatography with tandem mass spectrometry (LC‐MS/MS). The samples were extracted with acetonitrile (1%, glacial acetic acid, v/v) and purified using primary secondary amine and octadecylsilane. The limit of detection was 0.01–0.13 mg/kg, whereas that of quantification was 0.02–0.40 mg/kg for spirotetramat and its metabolites. The average recoveries of spirotetramat, spirotetramat‐enol, spirotetramat‐mono‐hydroxy, spirotetramat‐enol‐glucoside and spirotetramat‐ketohydroxy in all matrices were 73.33–107.91%, 75.93–114.85%, 76.44–100.78%, 71.46–103.19% and 73.08–105.27%, respectively, with relative standard deviations < 12.32%. The dissipation dynamics of spirotetramat in citrus and soil followed first‐order kinetics, with half‐lives of 2.3–8.5 days in the three sampling locations. The terminal residues of spirotetramat in four matrices at the three locations were measured below the 1.0 mg/kg maximum residue limit set by China, and residues were found to be concentrated on the peel. The risk assessment of citrus was evaluated using risk quotients. The risk quotient values were found to be significantly <1, suggesting that the risk to human health was negligible when using the recommended doses of spirotetramat in citrus. These results could provide guidance for the safe and proper application of spirotetramat in citrus in China.  相似文献   

4.
气相色谱法检测西兰花和荷兰豆中嘧菌酯残留量   总被引:3,自引:1,他引:2  
建立了气相色谱法检测西兰花和荷兰豆中嘧菌酯残留量的快速分析方法。样品用V(乙酸乙酯)∶V(环己烷)=1∶1超声波萃取,气相色谱-氮磷检测法测定。外标法定量,结果表明,嘧菌酯在0.01~1.0 mg/kg范围内呈线性关系,其相关系数r>0.99。在低、中、高3个添加水平,嘧菌酯的回收率为85%~110%,相对标准偏差为3.8%~11.4%,检出限为0.01 mg/kg。  相似文献   

5.
Pharmaceutical residues in the environment, and their potential toxic effects, have been recognized as one of the emerging research area in the environmental chemistry. The increasing attention, on pharmaceutical residues as potential pollutants, is due that they often have similar physico-chemical behaviour than other harmful xenobiotics which are persistent or produce adverse effects. In addition, by contrast with regulated pollutants, which often have longer environmental half-lives, its continuous introduction in the environment may make them “pseudopersistents”.Pharmaceutical residues and/or their metabolites are usually detected in the environment at trace levels, but, even that, low concentration levels (ng/L or μg/L) can induce to toxic effects. In particular, this is the case of antibiotics and steroids that cause resistance in natural bacterial populations or endocrine disruption effects.In this study, an overview of the environmental occurrence and ecological risk assessment of pharmaceutical residues is presented from literature data. Risk Quotient method (RQ) was applied as a novel approach to estimate the environmental risk of pharmaceuticals that are most frequently detected in wastewater effluents, surface waters and sediments.  相似文献   

6.
In this paper, the conversion of azoxystrobin in a strongly fluorescent degradation product by UV irradiation with quantitative purposes and its fluorimetric determination are reported for the first time. A multicommuted flow injection-solid phase spectroscopy (FI-SPS) system combined with photochemically-induced fluorescence (PIF) is developed for the determination of azoxystrobin in grapes, must and wine. Grape samples were homogenized and extracted with methanol and further cleaned-up by solid-phase extraction on C18 silica gel. Wine samples were solid-phase extracted on C18 sorbent using dichloromethane as eluent. Recoveries of azoxystrobin from spiked grapes (0.5-2.0 mg Kg−1), must (0.5-2.0 μg mL−1) and wine (0.5-2.0 μg mL−1) were 84.0-87.6%, 95.5-105.9% and 88.5-111.2%, respectively. The quantification limit for grapes was 0.021 mg Kg−1, being within European Union regulations, and 18 μg L−1 and 8 μg L−1 for must and wine, respectively.  相似文献   

7.
Commercial suspension emulsion (SE) of (8% chlorfenapyr + 20% clothianidin), as a pre-registered product in China, was firstly investigated under Chinese open-field conditions. A MWCNTs-based QuEChERS method for simultaneous determination of chlorfenapyr and clothianidin in leek was established and validated through RRLC-QqQ-MS/MS.  相似文献   

8.
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   

9.
The chemical insecticide flonicamid is widely used to control aphids on crops. Differences among crops make the universality of detection methods a particularly important consideration. The aim of this study was to establish a universal, sensitive, accurate and efficient method for the determination of flonicamid residues in peach, cucumber, cabbage and cotton. QuEChERS pretreatment was combined with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). A satisfactory recovery rate of 84.3–99.3% was achieved at three spiking levels, and the relative standard deviation (RSD) was 0.41–5.95%. The limit of quantification (LOQ) of flonicamid in the four matrices was 0.01 mg/kg. The residue and dissipation kinetics of flonicamid in four types of crops in various locations were determined by using the optimized method. The results showed that flonicamid had a high dissipation rate in the four different types of crops and a half-life in the different matrices and locations of 2.28–9.74 days. The terminal residue of flonicamid was lower than the maximum residue limit (MRL). The risk quotient (RQ) of flonicamid was 4.4%, which is significantly lower than 100%. This result shows that the dietary risk presented by using flonicamid at the maximum recommended dose is low and acceptable. The comprehensive long-term dietary risk assessment of flonicamid performed in this study provides a reference for the protection of consumer health and safe insecticide use.  相似文献   

10.
The present study investigates the occurrence of pymetrozine residues in cauliflower samples obtained from six cauliflower‐producing areas of China during fixed time periods in 2017 and estimates the dietary risk of pymetrozine in cauliflower. A liquid chromatography with tandem mass spectrometry method was developed and validated to detect pymetrozine in cauliflower. The samples were extracted using 20 mL of acetonitrile and purified with dispersive solid‐phase extraction using C18 as sorbent. The limit of quantification of pymetrozine was 0.008 mg/kg in cauliflower. The recoveries of the analyte were 82.04–95.18% with RSD <8.45%. The calibration curves for pymetrozine showed good linearities in the concentration range 0.004–2.0 mg/L with determination coefficients (R2) >0.999. Pymetrozine dissipated rapidly in cauliflower with a half‐life of <4 days. The terminal residues of pymetrozine were <0.008–0.0881 mg/kg in cauliflower at 7, 10 and 14 days after spraying from six sites. The routine washing process removed about half amount of the pymetrozine in cauliflower; the reduction ratios were 51.0–52.8%. The dietary risk assessment indicated that pymetrozine did not exhibit obvious dietary health risks in cauliflower when good agricultural practices were implemented.  相似文献   

11.
The dissipation of two fungicides (procymidone and azoxystrobin) was evaluated in greenhouse grown lettuce and under cold storage conditions. Lettuce samples were collected from an experimental greenhouse during a five week period, in which two consecutive applications of these pesticides were performed. Gas chromatography (GC) with electron-capture detection (ECD) was used to study the disappearance of these compounds in lettuce. Confirmation analysis of pesticides was carried out by capillary gas chromatography coupled with mass spectrometry in the selected ion monitoring (SIM) mode. The disappearance rates of these compounds on lettuces in field after two applications were described as pseudo-first-order kinetics with strong correlation between residue concentration and time (r was in all cases higher than 0.983). The half-lives for first and second applications were of 5.31 and 4.65 days for procymidone and 6.23 and 4.87 days for azoxystrobin, respectively. When procymidone and azoxystrobin were applied two times during cultivation, at maximum recommended dose, the residues of both pesticides were below maximum residue limits (MRLs) after the established preharvest intervals. After 21 days under cold and darkness storage conditions, dissipation of procymidone and azoxystrobin was not observed.  相似文献   

12.
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   

13.
Pesticide residue in food commodities is a serious concern in relation to consumer safety and also the most significant barrier in the trade of food commodities. The dissipation pattern of four insecticides, namely novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin, was evaluated on tomato fruits and cropped soil. The residues were extracted using the QuEChERS analytical method and quantized using a gas chromatograph with electron capture detector, gas chromatograph mass spectrometer, and high-performance liquid chromatography with photo diode array detector. The analytical method was validated using parameters like recovery, linearity, accuracy, matrix effect, and specificity, with limit of detection and limit of quantitation established to be 0.01 and 0.05 mg/kg, respectively, for all the pesticides. The average initial deposits (samples collected after 2 h of application) at the recommended dose of novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin were 0.593, 0.293, 0.227, and 0.431 mg/kg on tomato fruits, respectively, and were below the limit of quantification in soil. The pre-harvest interval of 17, 8, 1, and 13 days was suggested for novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin on tomato, respectively. Risk assessment studies revealed that all pesticides under study are safe and do not pose any threat to humans as theoretical maximum dietary intake is less than the maximum permissible intake and acceptable daily intake.  相似文献   

14.
The chemical fungicide fludioxonil is widely used to control post-harvest fungal disease in cherries. This study was implemented to investigate the dissipation behaviours and residues of fludioxonil on cherries. A reliable and efficient analytical method was established. Cherry samples from four product areas were analyzed by QuEChERS and HPLC-MS/MS methods with acceptable linearity (R2 > 0.99), accuracy (recoveries of 81–94%), and precision (relative standard deviation of 2.5–11.9%). The limits of quantification (LOQs) and limits of detection (LODs) of cherries were 0.01 mg/kg and 0.005 mg/kg. The dissipation of fludioxonil on cherries followed first order kinetics with half-lives of 33.7–44.7 days. The terminal residues of fludioxonil were all lower than 5.00 mg/kg, which is the MRL recommended by the European Commission. According to Chinese dietary patterns and terminal residue distributions, the risk quotient (RQs) of fludioxonil was 0.61%, revealing that the evaluated cherries exhibited an acceptably low dietary risk to consumers.  相似文献   

15.
为了解泰安市城区土壤重金属污染特征,对采集的30件土壤样品中6种重金属含量进行测定,利用单因子污染指数法、内梅罗综合污染指数法、地累积指数法和潜在生态风险指数法开展污染状况评价。结果表明:土壤中As、Cd、Cu、Pb、Hg、Ni的平均含量分别为6.72、0.066、20.33、18.19、0.031和19.92 mg.kg-1,其中As、Cd、Cu、Pb、Ni的平均含量均低于泰安市和山东省土壤背景值,Hg的平均含量略高于泰安市土壤背景值,变异系数大于0.6,其含量受人类活动影响较大,空间分布差异性较大;除Hg的单因子污染指数为1.03,严重污染、中度污染、轻微污染和无污染采样点数量占比分别为3%、7%、23%和67%,其他重金属单因子污染指数平均值小于1,为无污染状态;重金属内梅罗综合污染指数平均为1.58~1.64,整体属于轻污染水平;土壤重金属累积较轻,多数为无污染状态,Hg的最大地累积指数为1.29,达中等-强污染(3级);综合生态风险指数RI的范围为39.96~191.81,平均值为77.60,综合生态风险等级为轻微,为低生态风险区,Hg为引起风险的主要因子;Cu、Ni含量较低,富集主要受土壤母质和自然过程的控制;Pb、Cd、As主要来源于自然背景因素,部分受人类活动影响;Hg的污染来源于化肥、塑料地膜和含重金属的无机农药使用,受农业活动和居民生活影响较大。  相似文献   

16.
Abstract

The use of organophosphorus pesticides is undeniably beneficial in agriculture and veterinary medicine, but their excessive use can pollute the environment, as well as contaminate foodstuffs. The objective of this study was to assess contamination of vegetables and fruits available in Poland by organophosphate pesticides (ethoprophos, diazinon, chlorpyrifos, chlorpyrifos-methyl, parathion-methyl, fenchlorphos, merfos,, as well as to assess a potential health risk posed to consumers. The pesticide content was determined by gas chromatography-mass spectrometry (GC-MS). The pesticides were detected in the peel and pulp of vegetables and fruits from Polish crops, as well as imported ones. Pesticide levels in most products were higher in the peel than in the pulp. Neither chlorpyrifos-methyl nor fenchlorphos were found in the material under study. Chlorpyrifos was the pesticide occurring in the highest levels in the peel of both vegetables (31?ng?·?g?1 w.w.) and fruit (9.3?ng?·?g?1 w.w.). The Maximum Residue Level (MRL) for parathion-methyl was exceeded in some samples of zucchini pulp of Spanish origin and in the peel of potato from Poland. But levels of other pesticides in the studied vegetables and fruits were significantly lower than the current MRLs. The assessment of consumer health risk showed a significantly lower Lifetime Average Daily Dose (LADD) of pesticides under this study comparing to the Acceptable Daily Intake (ADI). Moreover, the Hazard Quotient (HQ) was low with a maximum of 3.93?×?10?2 for vegetables and 4.26?×?10?3 for fruits. These estimated HQs were within the safe acceptable limits, indicating low risk to human populations from exposure to organophosphorus pesticides in the study area.  相似文献   

17.
ABSTRACT

This study was conducted to investigate the residues of pyrethroid and organophosphorus pesticide in flour and breads which were collected from local markets in Kermanshah province, Iran. Four different types of breads and two types of flour samples with high distribution were taken from market and their residues of pesticides were measured. A simple dispersive liquid–liquid microextraction (DLLME) method with solidification of floating organic drop was developed for the measurement. The health risk of these pesticides on adults and children health was assessed by target hazard quotient (THQ) using Monte Carlo simulation (MCS) method. About, 15% and 11.1% of total samples contained detectable levels of deltamethrin and malathion, respectively. None of the tested samples showed any permethrin residue. The results from all samples showed that none of the pesticides exceeded the maximum residue limits (MRLs). About 85% of pesticide residue detections were observed in tropical and mild weather area which is due to high consumption rate of insecticides in these areas. The percentile 95% of THQ is due to bread ingestion content of deltamethrin which was 0.033 and 0.070 for the adults and children, respectively, while this value for malathion was found to be, 0.015 and 0.030, respectively. In the adults and children for both deltamethrin and malathion, the percentile 95% of THQ value were lower than 1 (acceptable level). The non-carcinogenic health risk assessment indicated that bread consumers in Kermanshah province are not at a considerable risk because of deltamethrin and malathion.  相似文献   

18.
There is an increasing need to address the potential risks arising from combined exposures to multiple residues from pesticides in the diet. Pesticide residue-related pollution is a problem that arises because of the increased use of pesticides in agriculture to meet the growing demands of food production. In this study, pesticide residue data were obtained based on an optimized extraction method. For this purpose, we established a method based on qu ick, e asy, ch eap, e ffective, r ugged, and s afe (QuEChERS) extraction for simultaneous determination of imidacloprid (IMI) and acetamiprid (ACT) in pistachio nuts. The parameters influencing the QuEChERS method were the sample-to-water ratio and adsorbent amounts. As a result, both were optimized to improve the recovery of the analytes as well as the clean-up efficiency of the pistachio matrix. Our results indicated that a freeze-out step and use of primary and secondary amines as an adsorbent led to much cleaner chromatograms with lower baseline drift, without using graphitized carbon black and C18-based adsorbent, which reduced both cost and time of analysis. Following extraction, the pesticide residues were separated and quantified by reverse-phase HPLC. For validation purposes, recovery studies were carried out using a concentration range from 20 to 2500 μg/L at nine levels. The suitable linearity, precision, and accuracy were obtained with HPLC–UV with recoveries of 70.37%–89.80% for IMI and 81.05%–113.57% for ACT, with relative standard deviations <12%. The validated method was successfully applied to the analysis of pistachio samples collected from a field trial to estimate maximum residue limits. There was no significant health risk for consumers via pistachio consumption.  相似文献   

19.
Apple, a major fruit of temperate Himalayas, is sprayed with chemical pesticides around 12 times during the cropping season. Various systemic and contact fungicides are applied for the management of major diseases. In order to manage disease, flusilazole 40 EC is frequently used. However, excessive chemical application has been found to be detrimental for consumer safety. Keeping in view consumer safety, risk assessment, the half-life and waiting period for flusilazole 40 EC were evaluated on the Red Velox variety of apple. The QuEChERS (quick, easy, cheap, effective, rugged and safe) method and high-performance liquid chromatography were adapted for sample processing and analysis, respectively. The recovery percentages of flusilazole at three fortification levels (0.04, 0.09 and 0.50 mg kg−1) were 98.85, 99.83 and 98.98%, respectively. Flusilazole at the recommended dose (80 g a.i. ha−1) left an initial deposit of 0.733 mg kg−1, which dissipated by 93.45% in 60 days and was non-detectable beyond this period. Meanwhile flusilazole at double the recommended dose (160 g a.i. ha−1) left an initial deposit of 0.913 mg kg−1, which dissipated by 93.43% in 70 days and was non-detectable beyond this period. Based on the maximum residue limit of 0.3 mg kg−1 as prescribed by the Codex Alimentarius Commission, a waiting period of 28.74 and 46.03 days was recorded for single and double doses, respectively. Moreover, in order to assess the consumer risk, theoretical maximum residue contributions (TMRCs) were derived using flusilazole residues (average and maximum) recorded at various time intervals and compared with the maximum permissible intake, which was found to be 0.42 mg per person per day. Based on the average per capita daily consumption of 6.76 g apple in India, the TMRC values were computed. Although the values of TMRC decreased below maximum permissible intake at the first day after application, indicating minimal consumer health risks, fruits sprayed with a double dose of flusilazole carried the risk even up to the tenth day after flusilazole application. The results of the present study will be valuable for safe and timely use of flusilazole on apple.  相似文献   

20.
Herein we report a novel, accurate and cost-effective gas chromatography method for the determination of average deposits of profenofos on green pea and cucumber following good agricultural practices. Additionally the risk assessment, dissipation and waiting period for profenofos were determined. The average initial deposits (2 h after spraying) of profenofos in/on green pea and cucumber were 3.41 and 3.62 mg kg−1 respectively following two applications at a 10 day interval of profenofos 50EC formulation. Profenofos residues on both of the substrates were below the detection limit of 0.05 mg kg−1 after 20 days at the recommended dosage. For risk assessment studies, the 20th day will be safe for consumers for consumption of green peas. The gas chromatography method was validated according to the SANTE guidelines using the various analytical parameters: linearity, accuracy, detection and quantification limits. The developed method is simple, selective and repeatable and can be extended for profenofos-based standardization of pesticide formulations for green pea/cucumber and their use as pesticides.  相似文献   

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