Determination of Pesticides Residues in Some Fruits and Vegetables Imported to Iraq

A study was carried out in the laboratories of the National Center for Pesticides Control/State Board for Plant Protection / Ministry of Agriculture in 2010-2011. The aim was to determine the residues of some pesticides in fruits and vegetables imported to Iraq from neighboring countries （Jordan, Syria, Turkey and Iran）. Two types of fruits （apples and oranges） and two types of vegetables （tomatoes and cucumber） were selected for the purpose of this study. These fruits and vegetables are the most agricultural products imported for human consumption in Iraq. Samples were taken from different border points and from local markets. Extraction, clean up and analysis were then processed. The results indicated the presence of small amounts of residues of certain pesticides such as Deltamethrin and Abamectin and Thiamethoxam in some samples. However, these amounts were less than the limit allowed internationally. No indication was observed for the presence of other pesticides residues such as Bifenthrin Trticonazol and Imidacloprid ... etc. in the samples analyzed. Therefore, there is a need to continuity of inspection on pesticides residues in agricultural products imported to Iraq in order to prevent the entry of contaminating materials and secure human safety.

Rapid screening of 420 pesticide residues in fruits and vegetables using ultra high performance liquid chromatography combined with quadrupole-time of flight mass spectrometry

A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were developed.The samples were extracted with acetonitrile/acetic acid(99:1,V/V),and clean-up by SinChERS-Nano(single-step,cheap,effective,rugged,safe,nano)column,determined by UPLC-Q-TOF/MS.The accurate mass database and MS/MS database which contains 420 pesticides were established,the automatic retrieval of detection results was carried on according to the accurate mass,retention time,isotope ratio,ion fragment information,and so on.Method verification was performed on leeks samples.The results showed that 420 pesticides had good linearity in the range of 0.1-100μg/L,and the correlation coeffificients(R2)was greater than 0.990.The limits of detections(LODs)and limits of quantifications(LOQs)of 420 pesticides were in range of 0.05-2.0 and 0.1-5.0μg/L,respectively.The average spike recoveries at 3 levels were 70.1%to 119.7%,and the relative standard deviations(RSD)were lower than 20%(n=6).With this method,a survey of pesticide residues was conducted for 110 samples of 10 different fruits and vegetables,which provided scientific data for ensuring pesticide residue safety of the fruits and vegetables consumed daily by the public.This method was simple,sensitive and accurate,and could be used for rapid screening of 420 pesticide residues in fruits and vegetables.

Simultaneous Screening of 733 Pesticide Residues in Fruits and Vegetables by a GC/LC-Q-TOFMS Combination Technique

In this paper,we report the construction of two accurate mass databases and the development of a combination detection method that simultaneously screens for 733 pesticide and chemical contaminant multi-residues via high-throughput liquid chromatography(LC)-and gas chromatography(GC)-quadru pole-time-of-flight mass spectrometry(Q-TOFMS).This work demonstrates that electronic mass spectral standards may replace chemical-source standard materials as references through one sample preparation and the combination of GC/LC-Q-TOFMS screening.This cutting-edge technique has also replaced multiresidue determination using targeted detection with non-targeted screening.The pesticide residue types,sensitivity,recovery,and reproducibility of this combination technique are evaluated in eight fruit and vegetable matrices.This technique shows three advantages:①In comparison with the discovery capability of a single technique,the combination technique shows an improvement of 51.1%(GC-QTOFMS)and 39.6%(LC-Q-TOFMS),respectively;②the combination technique can satisfy a screening limit lower than 10μg·kg^-1 and meet the requirements of“uniform standards,”although some of the pesticide residues could be optimized to further improve screening sensitivity;③over 488 pesticides with recoveries between 60%-120%and relative standard deviation(RSD)<20%at a spiked level of 10μg·kg^-1 were detected with the combination technique in eight different matrices.From 2012 to 2017,this combination technique was applied in an investigation to screen pesticide residues from 1384 sampling locations for 38138 batched samples covering 18 categories and 134 types of fruits and vegetables obtained from across the mainland of China.After statistical analysis,533 pesticides in 115891 determinations were detected,and the regularity of pesticides in the fruits and vegetables sold on the Chinese market was shown.

Pesticide Residues and Government Regulation in China─Evidence from Pesticide Residues in Fruits and Vegetables

China is a big producer and exporter of fruits and vegetables,and pesticide residues are an important factor affecting the quality and safety of fruits and vegetables and their export trade.In this paper,we analyzed the pesticide residue data on fruits and vegetables in 32 major Chinese cities between 2012—2019,the export data of Chinese fruits and vegetables and the role of pesticides in foodborne diseases.The results showed that pesticide residues in fruits and vegetables(PRFV)partial excess of maximum residue standard(MRL)and residues of banned pesticide were still widespread in China.By comparing the standards of pesticide residues in the European Union and China and addressing the agricultural situation in China,this paper analyzed the main causes of PRFV in China and put forward some policy suggestions for strengthening government regulation of pesticide application in agricultural products.

QuEChERS-超高效液相色谱-串联质谱法检测果蔬中ipfentrifluconazole残留量

建立一种QuEChERS-超高效液相色谱-串联质谱法测定果蔬中ipfentrifluconazole残留的分析方法。样品经乙腈提取,无水硫酸镁、PSA、GCB净化,滤膜过滤后采用UPLC-MS/MS测定,外标法定量。结果表明,在质量浓度0.005~0.5 mg/L,方法线性关系良好,相关系数大于0.995,定量限均为0.01 mg/kg。在3个添加水平(0.01、0.1、0.5 mg/kg)下,ipfentrifluconazole在5种果蔬中的平均添加回收率为84.0%~102.1%,相对标准偏差为2.1%~12.7%。该方法简单、灵敏、高效,可用于果蔬中ipfentrifluconazole残留检测。

Statistical Analysis of Regularity of Pesticide Residues in Vegetables Produced in Inner Mongoli

[Objective]The paper was to study regularity of pesticide residues in vegetables produced in Inner Mongolia.[Method]Mathematical statistic analysis was carried out on 6 800 samples of veggies,fruits,leguminous vegetables,nuts and seeds produced in Inner Mongolia.[Result]The dominated vegetables in Inner Mongolia were green leafy vegetables,solanaceous vegetables and melon vegetables,and their yields accounted for 70%of the total vegetables production.Since 2003,with the rapid increase of detected vegetable numbers,the status of vegetable quality safety had entered into a new stage of sustainable steady after a rapid decline or periodic fluctuation,and the differences in safety levels were obvious,of which the range of exceeding standard rate of pesticide residues in solanaceous vegetables,melon vegetables and leguminous vegetables(about 55%of the total vegetables)was under 2%,with average values of 1.1%,1.6%and 3.1%,respectively.They belonged to stable type.The exceeding standard rate of pesticide residues in green leafy vegetables and Chinese cabbage group(about 30%of total vegetables)presented a decreasing trend year by year,wondering in the range of 7%-10%.They belonged to main risk type.The time period of exceeding standard of pesticide residues in root vegetables and cole vegetables was under predictable,and its exceeding standard rate in some years was over 5%(amplitude variation is over 15percentage points).They belonged to random risk type.The kinds of pesticides,which exceeding standard rate in vegetables were relatively intensive,presented variance in different vegetable species.70%of the pesticides belonged to intermittent over-limits and the probability was below 5%.About 20%tradition pesticides often exceeded standard and their probabilities were over 30%.The exceeding standard of organophosphorus and carbamates pesticides in vegetables presented a decreasing tend,while the risk of some new pesticides containing nitrogen element and high effective pyrethroids showed an increasing tendency.[Conclusion]The paper provided decision making services for agricultural management departments.

Effect of low-temperature plasma on the degradation of omethoate residue and quality of apple and spinach

Dielectric barrier corona discharge was developed to generate low-temperature plasma(LTP) to treat apple and spinach samples contaminated with omethoate. Experimental results showed that,after 20 min exposure, the degradation rate of omethoate residue in apple and spinach was(94.55± 0.01)% and(95.55 ± 0.01)%, respectively. When the treatment time was shorter than 20 min,the contents of moisture, vitamin C and beta-carotene were not affected by LTP. Exploration of related mechanisms suggested that LTP might destroy unsaturated double bonds of omethoate and produce phosphate ion, eventually leading to omethoate destruction. It is concluded that appropriate dosage of LTP can effectively degrade omethoate residue in fruits and vegetables without affecting their quality.

Characterization of Health and Environmental Risks of Pesticide Use in Market-Gardening in the Rural City of Tori-Bossito in Benin, West Africa

A study on the use of pesticides in market-gardening production was carried out on 108 market-gardeners in the rural city of Tori-Bossito in Southern Benin. The objective of the study was to characterize the potential risks of pesticides usage by farmers and the impacts on their health and on the environment. Two risk indexes were calculated for each pesticide: an environmental risk index (ERI) and a health risk index (HRI). First stage larva of the mosquito Aedes aegypti were used as bio-indicator for detecting insecticide residue in vegetable before their harvesting on the farms. The highest ERI were obtained for carbofuran, chlorpyriphos ethyl and endosulfan. Pesticide residues were found in 42% of the samples of leaves of eggplant, cucumber, amaranth and solanum. Vegetables growers used pesticides that may be highly hazardous and which were not registered in most cases. These situations could have unexpected consequences including the exposure of consumers to health hazards.

Multi-Residue Levels of Persistent Organochlorine Pesticides in Edible Vegetables: A Human Health Risk Assessment

Background: This study evaluates the quantitative assessment of persistent organochorine pesticide (OCPs) residues in vegetables (Senecio biafrae) from four selected cocoa plantations in Ekiti State, Nigeria. Methods: The pesticides were extracted from the vegetable samples by using USEPA 3500C method and later clean-up on activated silica gel. The pesticides residues in the samples were determined using Gas Chromatography coupled with Electron Capture Detector (GC-ECD). Results: The results showed that the analyzed samples were contaminated with ten OCPs. The mean OCPs concentration ranged from ND—0.399 mg/kg to ND—0.379 mg/kg during the wet and dry seasons respectively. α-BHC, β-BHC, p, p’-DDE, dieldrin, endrin, endosulfan sulphate and methoxychlor were not detected in the samples. Pesticides such as aldrin, endosulfan II, endrin aldehyde and heptachlor slightly exceeded their maximum residue limit. Conclusion: The hazard indices (HI) of heptachlor, endosulfan I, endosulfan II, aldrin, heptachlor-epoxide and p, p’-DDT exceeded 1 and thus pose likely potential non-carcinogenic health risk.

Monitoring of Pesticide Residues in Commonly Used Fruits in Hyderabad Region, Pakistan

A market based survey was carried out to evaluate the level of 26 pesticides in some commonly used fruits in Hyderabad region, Pakistan. Gas chromatography coupled with micro electron capture detector was used to assess the levels of pesticide residues. Gas chromatography-mass spectrometry (GC-MS) was also applied for the confirmation of results. Out of total 131 analyzed samples, 53 (40%) were found contaminated with pesticide residues while only 3 (2%) samples were exceeded the MRLs of some pesticides. Chlorpyrifos and dieldrin were detected in almost all analyzed samples. Residues of chlorpyrifos (1256 μg/kg) and endosulfan sulfate (1236 μg/kg) were found higher in orange and apple samples, respectively. The findings of this study provided important data about contamination of pesticide residue in some fruits sold in Hyderabad, Pakistan, and recommended that monitoring studies should be expanded to other fruits grown in different agro climatic regions, which may serve as basis for future policy about the standards and quality control of pesticides.

A Device for Rapid Detection of Dithiocarbamate Pesticide Residues in Fruits

Based on the chemical properties of dithiocarbamate pesticides,a device for rapid detection was developed in the paper,and the experimental conditions were optimized. Dithiocarbamate residues in fruits were successfully detected using molecular absorption spectro-photometry,and the recovery rate was over 80%.The rapid detection method was simple to operate with low cost,and was conducive to application in basic level and enterprise laboratories.

Determination of Organochlorine Pesticide Residues in Pumpkin, Spinach and Sorrel Leaves Grown in Akwanga, Nasarawa State, Nigeria

Three green leafy vegetable samples of pumpkin leaves, spinach leaves, and sorrel leaves were collected from a farm in Akwanga and were tested for the presence of residues of organochlorine pesticides. The concentrations of all the pesticide residues in the vegetable samples were determined using GC/MS. Among the organochlorine pesticide p,p’-DDT was detected in pumpkin (0.75 mg/kg), spinach (0.319 mg/kg) and sorrel (0.219 mg/kg). θ-BHC and γ-BHC were detected only in pumpkin leaves (0.359 mg/kg and 0.647 mg/kg respectively). Dieldrin was detected in spinach and sorrel (0.124 mg/kg and 0.053 mg/kg respectively). Endrin was detected in pumpkin (0.732 mg/kg) and Aldrin in sorrel (0.095 mg/kg). All these values were above the maximum residue limit (MRL) value of the pesticides. Endosulfan II was detected in sorrel (0.306 mg/kg) below the MRL. The levels of most of the pesticide residues found in vegetables were above the maximum residue limits (MRLs) that call for laws to regulate the use and circulation of such chemicals. Routine monitoring of pesticide residues in this study area is necessary for the prevention, control and reduction of environmental pollution, to minimize health risks.

Pesticide Residue Content in Vegetable Bases of Lhasa City

[Objectives]To understand the quality safety of vegetables produced in vegetable planting bases around Lhasa City.[Methods]Four vegetable planting bases in the east,west,south,and north of Lhasa City were randomly selected for testing using rapid measuring instrument for agricultural residues and solid-phase microextraction-gas chromatography-mass spectrometer,with 120 vegetable samples selected.The testing samples included seven categories:green leafy vegetables,eggplants,melons,onions and garlic,root vegetables,beans,and fungi,totaling 29 types of vegetables.The samples were tested for 8 common prohibited and restricted pesticides in organic phosphorus and carbamate esters,including methamidophos,parathion,methyl parathion,monocrotophos,isocarbophos,methamidophos,aldicarb,and carbofuran.[Results]The pesticide inhibition rate of 6 kinds of vegetables detected by the rapid measuring instrument for agricultural residues was relatively high,with green leafy vegetables being the majority,reaching over 25%.By further establishing a solid-phase microextraction-gas chromatography-tandem mass spectrometry method,the accuracy of the data was verified experimentally.The experimental results indicated that the inhibition rate of vegetable samples in this experiment did not exceed 15%,and it was determined as a pollution-free vegetable.[Conclusions]According to the restriction standard of national pesticide use,the inhibition rate of vegetable samples was less than or equal to 40%,indicating that the quality of vegetables was qualified.

柠檬汁还原法制备AgNPs用于果蔬农药残留的SERS快速检测

[目的/意义]为满足目前市场上对农产品农药残留的快速灵敏检测需求,报道一种基于柠檬汁还原制备银纳米粒子(AgNPs)的方法。[方法]首先将新鲜柠檬汁经滤纸过滤,稀释成2%的柠檬汁水溶液,再配制一定浓度的AgNO3溶液、50 mM的NaOH溶液,放置室温保存。然后在室温下,将10 mL的ddH2O、2mL的NaOH、2mL的2%柠檬汁和5 mL的AgNO3溶液混合,待溶液颜色变为澄清的黄色时,溶液离心即可获得AgNPs。[结果和讨论]该方法制备的AgNPs,其颗粒形貌大小基本均一,约为20 nm,具有很好的表面增强拉曼散射(Surface Enhancement of Raman Scattering,SERS)增强效应,即良好的SERS信号稳定性,较强的SERS增强性能。该胶体中AgNPs分散较均匀,并且具有较长时间储存的稳定性,因此可用于微量农残检测。柠檬汁中主要还原成分抗坏血酸、葡萄糖和果糖,其含量分别为395.76μg/mL、5.95 mg/mL和5.90 mg/mL。将柠檬汁还原法制备的AgNPs用于果蔬表面农残检测,对于百草枯、多菌灵的检出限分别最低至3.90 ng/kg及0.22μg/kg。[结论]这项工作为果蔬农残快检提供了一种绿色、便捷的SERS材料制备方法,为实现农产品农药残留的快速、灵敏检测提供一种新的途径。

静电场轨道阱高分辨质谱法快速筛查上海市流通环节蔬菜的农药残留

目的建立静电场轨道阱高分辨质谱法快速筛查蔬菜中农药多残留的方法。方法使用QuEChERS法净化蔬菜样品,结合静电场轨道阱高分辨质谱法开展809种农药的快速非靶向筛查。结果62种阳性农药的筛查限(screening detection limit,SDL)为0.005~0.010 mg/kg,定量限(limits of quantitation,LOQ)为0.01 mg/kg,线性范围为10.0~200.0μg/L,线性相关系数(r^(2))为0.9917~0.9997,日内精密度为2.77%~6.98%(n=5),日间精密度为4.82%~10.8%(n=5)。200批次样品共检出62种农药,不合格样品28批次,不合格率为14.0%。豇豆的不合格情况比较突出,不合格样品22批次,主要的不合格项是灭蝇胺和噻虫胺。结论该方法快速、准确、分析通量高,在无标准品的情况下实现了蔬菜中809种农药的非靶向快速筛查,可为蔬菜农药残留风险监测和质量控制提供支撑。

2022年泰安市市售蔬菜中农药残留状况分析

目的:通过对2022年泰安市市售蔬菜中农药残留检测数据进行分析与研究,为相关部门制定监管措施提供理论支撑。方法:2022年在泰安市的6个县(市、区)采集了160份蔬菜样品进行了农药残留检测,并根据《食品安全国家标准 食品中农药最大残留限量》(GB 2763—2021)对农药残留检测结果进行评价。结果:在160份蔬菜样品中有88份样品检测出了农药残留,检出率为55.00%。其中,20份蔬菜样品农药残留超标,超标率为12.50%。各类蔬菜中以甘蓝类检出率和超标率最高,其次为叶菜类。有机磷类农药检出率和超标率最高,分别为34.38%、11.88%。结论:泰安市市售蔬菜中存在一定程度的农药残留情况,需引起相关部门的重视并进一步加强监管。

QuEChERS结合GC-MS/MS检测果蔬中13种农药残留

目的:基于QuEChERS方法结合气相色谱串联质谱(Gas Chromatography-Tandem Mass Spectrometry,GC-MS/MS)技术,建立一种简单、快速检测果蔬中农药残留的方法。方法:果蔬样品匀浆后,先用乙腈和乙酸缓冲盐包提取,再用m-PFC小柱净化,最后用GC-MS/MS测定,外标法定量。结果:13种农药在10~500μg·L^(-1)浓度范围内线性关系良好,相关系数(R^(2))均大于0.994,检出限为0.35~0.92μg·kg^(-1),定量限为1.0~2.8μg·kg^(-1);13种农药在3个水平下的加标回收率为82.4%~110.1%,相对标准偏差为2.9%~9.3%。结论:所建立的方法可操作性强,具有较高的精密度和准确度,可用于果蔬中农药残留的定性和定量检测。

超高效液相色谱串联质谱法同时测定蔬菜中12种新烟碱类农药残留量

目的建立同时测定蔬菜中12种新烟碱类农药残留量的超高效液相色谱串联质谱法(UPLC-MS/MS)法。方法采用乙腈提取样品,经N-丙基乙二胺(PSA)、石墨化炭黑(GCB)基质分散净化进行预处理。色谱柱为Waters Acquity HSS T_(3)柱(100 mm×2.1 mm,1.8μm),流速为0.3 mL/min,流动相为甲醇-水(梯度洗脱),柱温为40℃,进样量为2μL;质谱分析采用电喷雾正离子多反应监测(MRM)模式,电喷雾电压为4500 V,气帘气压力为40 psi,雾化气压力为60 psi,辅助气压力为60 psi,离子源温度为550℃。采用空白基质外标法定量测定20份陕西省市售蔬菜中12种新烟碱类农药的残留量。结果12种新烟碱类农药在各自质量浓度范围内与峰面积线性关系良好(r>0.994);检测限为0.2~2.0μg/kg,定量限为0.5~3.0μg/kg;精密度试验的RSD均小于3.5%(n=6);加样回收率为82.42%~102.06%,RSD为2.12%~4.76%(n=6);基质效应为0.83~0.96。20份蔬菜样品中,检出阳性样品13份,其中,8份检出噻虫胺(0.83~67.92μg/kg),9份检出噻虫嗪(0.84~87.22μg/kg),4份检出啶虫脒(5.78~98.40μg/kg),3份检出吡虫啉(14.12~42.34μg/kg),3份检出烯啶虫胺(3.88~192.00μg/kg),2份检出呋虫胺(3.58,10.12μg/kg),1份检出氯噻啉(5.76μg/kg)。结论所建立的方法灵敏度高、准确性好,可用于蔬菜中12种新烟碱类农药的残留量测定。

SPS监管差异对中国果蔬类农产品出口贸易的影响——基于农药最大残留限量标准视角

利用2022年中国对157个国家(地区)出口50种果蔬类农产品贸易数据,采用Heckman两阶段模型,基于农药最大残留限量(MRLs)视角,实证分析SPS监管差异对中国果蔬类农产品出口贸易的影响。结果表明:SPS监管差异抑制中国果蔬类农产品出口的二元边际,即贸易成本效应大于竞争优势效应,贸易成本效应抑制扩展边际和集约边际,而竞争优势效应仅促进集约边际;SPS监管差异对中国向发达国家出口以及对蔬菜农产品出口的抑制作用更大;杀菌剂监管差异对集约边际和扩展边际均具有抑制作用,而杀虫剂监管差异仅抑制集约边际。据此,提出对标国际高标准SPS措施、帮助中小型企业克服技术难关、宣传食品安全理念等政策建议。

氨基化-多壁碳纳米管QuEChERS-液相色谱-串联质谱法测定热带水果中110种农药及其代谢物残留量

建立基于氨基化-多壁碳纳米管(amino-functionalized multi-walled carbon nanotubes,NH2-MWCNTs)改进的QuEChERS净化方法,结合液相色谱-串联质谱(LC-MS/MS)测定3种热带水果中110种农药及其代谢物残留量。样品经乙腈提取,采用欧洲标准(EN.15662)萃取缓冲体系QuEChERS盐包提取,NH2-MWCNTs改良的分散固相萃取(d-SPE)净化管净化,多反应监测模式(MRM)分析,基质匹配标准曲线外标法定量。结果表明:在0.002~0.2 mg/L范围内110种农药及其代谢物具有良好的线性关系,决定系数(R2)均高于0.9902,定量限(LOQ)为0.005~0.05 mg/kg,添加回收率为61%~120%,相对标准偏差(RSD)为0.30%~15%(n=6)。该方法净化效果好,能在短时间内可靠地分析样品。灵敏度、正确度、精密度均满足日常检测定性、定量需求,适用于荔枝、龙眼和香蕉等热带水果中农药多残留的快速检测。