Method For Multiresidue Analysis Of Pesticides Research Articles

Higher early than late-season residue load of pesticides in honey bee bread in Slovakia

Bees are often exposed to pesticide residues during their foraging trips in agricultural landscapes. The analysis of in-hive stored pollen reflects the spectrum of visited plants and can be almost used to link the exposure to pesticides.In the current study, bee bread samples were collected in May and July from 17 sites located in southern Slovakia. Samples were analysed using a multi-residue pesticide analysis method for a broad spectrum of active substances and microscopic for pollen identification.Our results revealed a bee bread contamination with 19 different active substances, with fungicides being predominant. Sixteen of them are authorized in the EU, but chlorpyrifos, chlorpyrifos-methyl, and chloridazon are not. The highest concentrations for pendimethalin (1400 µg/kg), fluazifop-butyl (640 µg/kg), fenpropidin (520 µg/kg), fluopyram (130 µg/kg), and difenoconazole (95 µg/kg) were detected. The total residue load in bee bread sampled in the early season (May) was significantly higher than in the late season (July). The mean residue load of insecticides analysed in July comprised 46% of May’s load, which is alarming due to the importance of bee bread in the diet for winter-rearing bees. Moreover, results from both sampling periods showed that fungicides were positively associated with plant families Apiaceae and Papaveraceae and herbicides with Aceraceae, Salicaceae, and Brassica-type/Brassicaceae.Hence, bee bread can be considered a suitable matrix and a good bio-indicator reflecting honey bee exposure to pesticides over the season.

Comparison of QuEChERS and Liquid–Liquid extraction methods for the simultaneous analysis of pesticide residues using LC-MS/MS

In 2004, the Food Code of Korea adopted a multi-class multi-residue pesticide analysis method, which employed liquid–liquid extraction (LLE) and solid-phase extraction for sample purification. After several modifications, the LLE stage was replaced by the QuEChERS method in October 2021. Thus, in the current study a comparison was carried out between the new QuEChERS method and the conventional LLE method for the simultaneous analysis of multiple pesticide residues. More specifically, 275 pesticide compounds were measured in spinach, rice, and mandarin matrices using LC-MS/MS, and the linearity, LOD, LOQ, recovery, and matrix effect were determined. Following both the QuEChERS and LLE, the matrix-matched calibration curve plotted using the extracts of blank matrix extracts showed that the majority of pesticides exhibited a highly linear relationship, with coefficients of determination >0.99. In addition, the LOD was 0.00003–0.004 mg/kg, and the LOQ was 0.0001–0.01 mg/kg. For the different matrices, the average recovery of the QuEChERS method was 101.3–105.8%, while that of the LLE method was 62.6–85.5%. Due to the fact that the LLE and QuEChERS methods exhibited a tendency of suppression for the various matrices examined, matrix-matched calibration was required during quantification. Indeed, introduction of the QuEChERS method allowed matrix-matched calibration to be conducted during quantification, while the previously employed LLE method did not involve such processes. These changes therefore resulted in a more accurate quantification in addition to a reduced experimental time and cost. • We compared QuEChERS to LLE in multi-residue analysis in foods by LC-MS/MS. • QuEChERS has higher and more uniform recovery rates among matrices than LLE. • Both methods require matrix-matched calibration owing to ion suppression. • QuEChERS and matrix-matched calibration improve quantification accuracy.

Wide-scope multi-residue analysis of pesticides in beef by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Increasing pesticide contamination in foods of animal origin has made the wide-scope multi-residue analysis of pesticides an international concern. In this study, a sensitive and reliable multi-residue pesticide analysis method for beef was developed with the use of 129 pesticides to demonstrate the full scope of the method. The pesticides were extracted and purified using a modified QuEChERS technique and analysed using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. An orthogonal array design was employed for optimisation of the method, significantly scientising and simplifying the process. Method validation revealed satisfactory sensitivity with limits of quantification values ranging from 0.003 to 11.37 µg∙kg−1. Matrix effects ranged from 83.85% to 120.66%. Recovery at three spiking levels (20, 50, and 100 µg∙kg−1) were 70.51–128.12% and the intra-day and inter-day precisions were less than 20%, indicating good accuracy and precision.

Pesticide residues in daily bee pollen samples (April\u2013July) from an intensive agricultural region in Southern Germany

Insect-pollinated plants are essential for honey bees to feed their brood. In agricultural landscapes, honey bees and other pollinators are often exposed to pesticides used for cultivation. In order to gain more insight into the fluctuation of pesticide loads, 102 daily pollen samples were collected between April and July 2018 in a fruit-growing area in Southern Germany. Samples were analyzed with respect to more than 260 pesticides using a multi-residue pesticide analysis method. Almost 90% of the analyzed pollen samples featured between one and thirteen different pesticides. In total, 29 pesticides were detected at maximum concentrations of up to 4500 ng/g pollen. Maximum residual concentrations of most pesticides were observed during April and the first half of May, as well as during the second half of June. In most cases, serial data of pesticide residuals were detected for approximately 10 subsequent days with two or three maximum values, which were several folds higher than concentrations on the days before and thereafter. The pollen hazard quotient (PHQ) was calculated to estimate the risk of the detected pesticides to honey bees and wild pollinators.

Multiresidue GC-MS/MS pesticide analysis for evaluation of tea and herbal infusion safety

ABSTRACTA fast, simple, low-cost and high-throughput multiresidue pesticide analysis method was developed and validated for 300 pesticides in herbal and fruit infusion samples based on modified QuEChERS (quick, easy, cheap, effective, rugged and safe) procedure combined with gas chromatography coupled with tandem mass spectrometry method (GC-MS/MS). The objectives were to develop low cost GC-MS/MS method, validate the method in accordance to SANTE/11,813/2017 guidance document and application in routine. The results obtained using different GC and MS/MS parameters were evaluated in order to develop quick, robust, accurate and effective multiresidue method. Total analysis time was 28 min with 0.6 µL injection volume. For accurate quantification, matrix-matched calibration (MMC) curves (in range of 10 µg/kg – 250 µg/kg) were applied to compensate matrix effect. The limits of quantification (LOQ) were ranged between 0.06 µg/kg and 135 µg/kg, and for the majority of the pesticides the LOQ were below the regulatory maximum residue limits. Most recoveries at 10 µg/kg and 100 µg/kg were in the range 70%–120% indicating satisfactory accuracy. The validated method was applied to commercial herbal and fruit infusion products detecting chlorpyriphos, DEET, tebuconazole, terbuthylazine, piperonyl butoxide, biphenyl, pendimethalin, pirimiphos-methyl and p,p’-DDE in more than 100 samples from 1,466 so risk assessment on human health was calculated specially for those pesticides.

Behavior of pesticides and their metabolites in traditional Chinese medicine Paeoniae Radix Alba during processing and associated health risk

In Traditional Chinese Medicine (TCM), crude herbs are processed to obtain the medicinal parts of the plant, from which extracts are prepared for people to take as medicine. However, there is no report on the pesticide residual behavior in Chinese medicines during processing at present, and thus, a systematic study of the effects of different processing factors (PF) on pesticide removal in Chinese medicines and the associated risk of dietary exposure is urgently needed. This study main investigated the dissipation and metabolism of pesticides in Chinese medicine Paeoniae Radix Alba during processing, and the calculated pesticide PFs were also used to assess the risk of dietary exposure. For analyze samples, a simple and high-throughput multiresidue pesticide analysis method was developed and validated for pesticides and their metabolites in P. Radix. based on QuEChERS procedure combined with HPLC-MS/MS. Recoveries at three concentration levels were within 61.37%–117.82% with an associated precision RSD < 15% indicating satisfactory accuracy. TCM processing could be useful for the partial removal of several pesticide residues, with removal rate reaching 98%. The polarity is the dominant variable, which with a high contribution was the effectiveness of the treatment and the concentration factors for pesticides. The hazard quotients of all pesticides were much lower than the safety level, indicating low risk of dietary exposure. Results are of great theoretical and practical value for the scientific evaluation of the safety of Chinese medicines, improvement of the quality and safety level of Chinese medicine.

Multiresidue Analysis of 113 Pesticides in Different Maturity Levels of Mangoes Using an Optimized QuEChERS Method with GC-MS/MS and UHPLC-MS/MS

In this study, a simple and high-throughput multiresidue pesticide analysis method based on the quick, easy, cheap, effective, rugged, safe (QuEChERS) extraction combined with gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) is presented for the determination of 113 pesticides in green and ripe mangoes. Different buffer systems and purification sorbents were optimized to get better recovery. Extracts from mangoes after acid acetonitrile and ammonium acetate extraction were directly injected to UHPLC-MS/MS analysis, whereas other GC-amenable compounds were treated with cleanup approaches with a mixture of sorbents [400 mg primary-secondary amine (PSA) and 400 mg graphitized carbon black (GCB)] for GC-MS/MS analysis. Recoveries for the majority of pesticides at spike levels of 10, 50, and 100 μg/kg were ranged between 70 and 120% with RSD values below 20%. Limits of detection (LODs) were below 4 μg/kg, whereas limits of quantification (LOQs) were below 10 μg/kg. Response linearity was good in the range between 5 and 500 μg/kg. The matrix effect for 56 pesticides by GC-MS/MS analysis exhibited a non-significant matrix effect (≤ 25%) in green and ripe mangoes. For 57 pesticides used for UHPLC-MS/MS analysis, the optimized method in green mango provided no significant matrix effect (≤ 25%) for 63% of the compounds, whereas only for 16 and 21% compounds, the matrix effect was medium (25–40%) and strong (> 40%); the optimized method in ripe mango provided no significant matrix effect (≤ 25%) for 61% of the compounds, whereas only for 26 and 12% compounds, the matrix effect was medium (25–40%) and strong (> 40%). Following the application of a “top-down” approach, the expanded measurement uncertainty was both 21% on average (coverage factor k = 2, confidence level 95%) in green and ripe mangoes. The application of GC-MS/MS and UHPLC-MS/MS coupled with the modified QuEChERS extraction procedures was proved to adequately quantitate these pesticides in different maturity levels of mangoes.

Monitoring and distribution patterns of pesticide residues in soil from cotton/wheat fields of Pakistan.

The excessive use of hazardous pesticides for massive cotton and wheat production has deteriorated the quality of Okara district's soil. Thus, in order to sustain the production of good-quality food, it is essential to determine the residue levels of pesticides in the agricultural soil and define their possible sources. Thus, the present study focused on the determination of selected pesticides in the soil samples obtained from cotton/wheat fields by using the modified multi-residue pesticide analysis method based on GCMS and HPLC-UV. Most of soil samples were found to be highly contaminated with imidacloprid, chlorpyrifos, and α-cypermethrin residues. Selected pesticides were significantly correlated with each other at p<0.05 except imidacloprid, which was negatively correlated with triazophos, MCPA methyl ester, selected pyrethroid pesticides, and their metabolite. Soil pH and phosphate levels were significantly positively correlated while sulfate content was negatively correlated with most of selected pesticides. The varimax normalized factor analysis divides the selected pesticides to the two major factors that explained 87.19% of the total variance which evidenced that pesticide in the same cluster shared a common source in the soil. A significant negative correlation of chlorpyrifos in the second factor pointed towards a source different from other pesticides. Factor and cluster analysis indicated that sulfate levels of soil positively affected the persistence/ mobility of imidacloprid.

Multiresidue analysis of 213 pesticides in leek and garlic using QuEChERS-based method and gas chromatography-triple quadrupole mass spectrometry.

A simple and sensitive multiresidue pesticide analysis method was developed and validated for 213 pesticides in leek and garlic based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure combined with gas chromatography-triple quadrupole mass spectrometry. In the QuEChERS method, commercial extraction salt packet, dispersive solid-phase extraction adsorbent packet, and ceramic homogenizer were used to simplify the extraction procedure. The gas chromatography-tandem mass spectrometry (GC-MS/MS) parameters were optimized for analysis of 213 pesticides within a 38-min run time with a limit of quantification for most of the pesticides at 2 μg kg(-1). The coefficient of determination (r(2)) was >0.99 within the calibration linearity range of 2-400 μg kg(-1). Most recoveries at 2, 5, 10, 20, 50, 100, and 200 μg kg(-1) were in the range of 70-120% (n = 6) with associated relative standard deviations (RSDs) of <20%, indicating satisfactory precision. Real leek and garlic samples were analyzed for method application.

残留農薬分析における通知法とQuEChERS法のマトリックス成分の比較

残留農薬分析における通知法とQuEChERS法のマトリックス成分の比較

Multiresidue analysis of over 200 pesticides in cereals using a QuEChERS and gas chromatography–tandem mass spectrometry-based method

A simple and high-throughput multiresidue pesticide analysis method was developed and validated for 219 pesticides in cereals (corn, wheat flour and rice) based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure combined with gas chromatography–triple quadrupole mass spectrometry (GC–MS/MS). Different buffer system (acetate- and citrate-buffered) and sample to solvent ratios (sample amount) were compared in the modified QuEChERS procedure to get better recovery and clean-up results. The limits of quantification (LOQ) ranged between 5 and 50μgkg−1, and for the majority of the pesticides the LOQ were 5μgkg−1, which were below the regulatory maximum residue limits. The coefficient of determination (r2) was >0.99 within the calibration linearity range of 2–200μgkg−1 for the majority of the pesticides. Most recoveries at 5, 10, 20, 50, 100 and 200μgkg−1 were in the range 70–120% (n=6) with associated RSDs<20% indicating satisfactory accuracy.