Pesticide Multiresidue Methods Research Articles

MÉTODO MULTIRRESÍDUO DE AGROTÓXICOS EM POLPA DE AÇAÍ EMPREGANDO MÉTODO QuEChERS MODIFICADO E UHPLC-MS/MS

MULTIRESIDUE METHOD FOR PESTICIDES IN AÇAÍ PULP USING A MODIFIED QuEChERS METHOD AND UHPLC-MS/MS. The northern region of Brazil, particularly the states of Pará and Amazonas, concentrates the majority of açaí national production. Considering the possible use of pesticides in this species, this study aimed to develop a comprehensive method for the multiresidue determination of pesticides in açaí pulp, using a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with analysis by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS). Various parameters of extraction were investigated, and the method was successfully validated. Analysis by UHPLC-MS/MS provided high selectivity and sensitivity. The main modification to the original QuEChERS method was the use of the C18 adsorbent associated with primary secondary amine (PSA) in the clean-up step by dispersive solid phase extraction (d-SPE). The method was validated for 83 compounds, showing adequate accuracy (70 to 120%) and precision (RSD ≤ 20%). The method limits of quantification, established by recovery tests, ranged from 5 to 25 µg kg–1. The method limits of detection were from 1.5 to 7.5 µg kg–1. The method was applied to commercial samples of açaí pulp, and no pesticide residues were detected. The proposed method proved to be fast, efficient and suitable for multiresidue determination of pesticides in açaí pulp in routine analysis.

Plant Protection Products Residues Assessment in the Organic and Conventional Agricultural Production

The organic food is progressively enticing purchasers’ attention, as it is recognized to be better than the food produced by the conventional agriculture and more sustainable for the natural environment. Pesticides and their metabolites can enter the human body via food and water. In the food production, over 60 thousand chemical agents are applied, while 90% of the harmful substances are consumed. The organic production is based on the qualitative and healthy food using the natural resources in an ecologically sustainable way. The European Regulations set the maximum pesticide levels (MRLs) in the organic products, which are also regulated by The United States Department of Agriculture in their National program supported by The United States Environmental Protection Agency. It is imperative to bear in mind that in the products from the organic production, the multiple detections cannot be tolerated, i.e., that one product cannot contain more than two detected pesticide residues. In this paper, a multi-residue pesticide method has been developed to determine the pesticides in the agricultural products from the organic and conventional production. In this work, 60 pesticides were analyzed using a simple QuEChERS sample preparation procedure, followed by LC-MS/MS. The tomato, potato, apple, and carrot samples from the organic and conventional products were collected from the market and the pesticide residues assessment comparing the organic to the conventional was done.

Development and validation of a multiresidue method for pesticides and selected veterinary drugs in animal feed using liquid- and gas chromatography with tandem mass spectrometry.

Animal feeds are often reported to be contaminated with chemical residues, and when present above the maximum legal limit, these compounds can cause harmful effects to consumers of animal produce. Thus, animal feed safety is an important regulatory concern. The aim of this study was to optimise a multiresidue method for the simultaneous analysis of multi-class pesticides and a number of frequently used veterinary drugs using LC-MS/MS and GC-MS/MS. The method was validated in a range of feed matrices, including maize feed, poultry feed and mixed feed concentrate. The optimised sample preparation workflow involved extraction of feeds (5g) with ethyl acetate (10mL), followed by a freezing step (at -20°C) used for eliminating the matrix co-extractives. The extract was further cleaned by dispersive solid phase extraction with a combination of primary secondary amine, C18 and florisil sorbents. From the cleaned-extract, an aliquot was analysed by GC-MS/MS, while another portion of it was solvent-exchanged to acetonitrile:water (50:50) and then analysed by LC-MS/MS. This method effectively minimised the matrix interferences. A total of 192 pesticides was analysed by GC-MS/MS within a runtime of 22min. The LC-MS/MS method was validated for 187 compounds including 17 veterinary drugs. For most of the compounds, the limit of quantification (LOQ) was 0.01mg/kg. The recoveries at LOQ and higher levels ranged between 70% and 120%, with precision-RSDs of < 20%. The method provided a precise analysis in a wide range of market-feed samples. As shown, the method is suitable for regulatory and commercial testing purposes.

Quantitative determination of pesticide residues in specific parts of bee specimens by nanoflow liquid chromatography high resolution mass spectrometry.

The presence of pesticide residues in bees is of great interest, given the central role of bees as indicators for environmental assessment. The goal of this article is to propose a method to capture enhanced chemical information for these central environmental indicators. Most of the methods rely on the analysis of pooled samples rather than individual specimens due to practical sample preparation method considerations and limitations in sensitivity. This leads to miss information on the mapping of pesticides and actual amount of pesticide per specimen. In this article, a nanoflow liquid chromatography system coupled to high resolution mass spectrometry (using a hybrid quadrupole-Orbitrap instrument) has been applied for the development of a multiresidue pesticide method for the determination of 162 multiclass pesticides in specific part of honeybee samples (ca. abdomen, head or thorax). The reduced flow rate provided an enhancement in sensitivity and a strong reduction of matrix effects, thus only a quick and simple ultrasound assisted extraction using minute amount of sample was required. Satisfactory results were obtained for all tested analytes with concentration levels detected lower than 0.5 ng g-1 in all cases, thus being acceptable for monitoring purposes. Matrix effect was negligible for 94% of compounds. Extraction recoveries ranged from 70% to 105%, being within SANTE guidelines. Finally, the applicability of the method was demonstrated, by successful application to the analysis of contaminated honeybee samples, extracting useful information from specific bee parts of single specimens, thus, enabling pseudo spatially resolved chemical information.

Development of a Multiresidue Method for Endocrine-Disrupting Pesticides by Solid Phase Extraction and Determination by UHPLC-MS/MS from Drinking Water Samples.

A rapid and efficient method based on solid phase extraction and liquid chromatography-tandem mass spectrometry was validated, allowing the determination of the endocrine-disrupting herbicides (acetochlor, alachlor, amitrole and atrazine), fungicides (carbendazim, triadimefon, penconazole and propiconazole), and insecticides (carbaryl and carbofuran) in drinking water. Low method detection limits (0.01-0.64ng/L) and method quantification limits (0.03-2.13ng/L) were obtained with satisfactory recoveries and precision for the endocrine-disrupting pesticides. The method was applied for real drinking water samples collected in the area of the city of Hangzhou (Zhejiang, China); the results showed that carbendazim, atrazine and acetochlor were detected in the drinking water samples and acetochlor was the most detected analyte.

Multiresidue Method for GC-MS Amenable Multiclass Pesticides in Pineapple Fruit

A simple, rapid QuEChERS method is reported for simultaneous analysis of 86 multiclass pesticides in pineapple fruit. Based on a comparative recovery by three methods, the one involving ethyl acetate extractant and dSPE clean up with 50 mg PSA and 150 mg anhydrous sodium sulphate was found more appropriate and further validated following SANTE guidelines. The coeffiicient of determination (R2) value of all the pesticides ranged between 0.97–0.99. Limit of quantification (LOQ) of most of the compounds was10 ng g−1. Bifenox, bitertanol, carfentrazone ethyl, chlorfenvinphos, flusilazole, haloxyfop methyl, methamidophos, methyl paraxon, paclobutrazole and pyraclostrobin showed a higher LOQ of 50 ng g−1. Average recovery ranged within 70–120 per cent at 10, 50 and 100 ng g−1 fortification levels with RSDr, RSDwR below 20 per cent; Horwitz ratio between 0.5–2 at LOQ proved that this method is sufficiently accurate, repeatable and reproducible and therefore can be effectively utilized for pesticide residue analysis in pineapple fruits.

A simultaneous multiresidue analysis for 203 pesticides in soybean using florisil solid-phase extraction and gas chromatography–tandem mass spectrometry

A multiresidue analysis method for the simultaneous determination of 203 pesticides in soybean was developed using solid-phase extraction (SPE) and gas chromatography–tandem mass spectrometry (GC–MS/MS). Scheduled multiple reaction monitoring by GC–MS/MS was optimized in electron ionization mode. The target pesticides satisfied the method limit of quantitation below 0.01 mg/kg, and an excellent instrumental repeatability was obtained. The calibration curve correlation coefficients (r2) for 201 (99.0%) pesticides were ≥ 0.990. The Multiclass Pesticide Multiresidue Method (No. 2) of the Korea Food Code was scaled down and applied for efficient sample treatment. Soybean sample (10 g) was extracted with 20 mL acetonitrile. The sample was filtered, partitioned with sodium chloride, and centrifuged. The supernatant (8 mL) was subjected to cleanup with a florisil SPE cartridge (500 mg), and the final extract was subjected to GC–MS/MS analysis. To remove fat, further liquid–liquid partitioning with n-hexane/acetonitrile was conducted before the SPE cleanup, and this procedure was compared to the non-partitioning procedure. The percentage of pesticides satisfying the recovery range of 70–120% with a relative standard deviation ≤ 20% in the non-partitioning and partitioning procedures were 87.2% and 78.8% at 0.01 mg/kg and 88.2% and 76.8% at 0.05 mg/kg, respectively. The average matrix effect value (%) was 5.5%. This miniaturized analytical method can be successfully applied for rapid and sensitive monitoring of multiresidues in soybean and related agricultural products.

Evaluation of the reproducibility standard deviation in the pesticide multi-residue methods on olive oil from past proficiency tests

The data reported in the frame of proficiency testing (PT) exercises organized from 2007 to 2016 have been statistically re-evaluated using Algorithm A of the ISO 13528:2015, and the relative standard deviation for reproducibility of multi-residue methods for the determination of pesticides in olive oil was evaluated. Usually, the assigned between-laboratories variability in PTs on pesticide residues is fixed/set to 25 %. This value was compared to the calculated robust relative standard deviation (RRSD). A total of 1527 analytical results were collected in the ten PTs for the determination of pesticides in olive oil. An RRSD of 21 % was obtained, below the maximum value of 25 %. If all participants use the same analytical approach (e.g., multi-residue method and same instrumental technique), a lower value of the reproducibility standard deviation should be expecting. The QuEChERS method, coupled with LC–MS/MS and GC–MS/MS, has become an important methodology for the analysis of pesticide residues. This is due to its simplicity, the use of low quantities of acetonitrile, the possibility to analyze a large number of pesticides with fewer steps and high efficiency. This method may harmonize the future of pesticide residue analyses. Recently, it was successfully applied to the analysis of olive oil by 70 % of the laboratories participating to our last PT exercise. An expanded uncertainty of 50 % was systematically applied in Europe since 2006 for the analyses of pesticides; the use of the QuEChERS methodology may reduce to 40 %. This work could contribute to promote the comparability of measurements of pesticide residues in foodstuffs.

Multi-residue pesticide analysis in virgin olive oil by nanoflow liquid chromatography high resolution mass spectrometry

In this article, a nanoflow liquid chromatography system coupled to high resolution mass spectrometry (nanoflow LC/ESI Q-Orbitrap-MS) has been applied for the development of a multiresidue pesticide method for the determination of 162 multiclass pesticides in olive oil samples. Due to the relatively high lipid content of the raw QuEChERS acetonitrile extracts obtained from this type of fatty vegetable samples, a dispersive solid phase extraction (dSPE) sorbent proposed to retain both fatty acids and triglycerides, namely Enhanced Matrix Removal-Lipid (EMR-Lipid) has been implemented as additional cleanup step. The analytical performances of the proposed method were evaluated,achieving recoveries in the range 75–119% with relative standard deviations lower than 19% (n = 6). The dSPE sorbent allowed the removal of most coextracted interferences without a significant loss of analytes. Matrix effects were also evaluated, showing a negligible effect for most of the compounds tested, when a dilution factor of 50 was applied. Notably, despite the use of relatively high dilution factors (e.g. 1:50) to minimize matrix effects, the lowest concentration levels detected with this method – in the low μg kg−1 range – are well below the corresponding maximum residue levels established by the current European legislation.

Multi-Residue Determination of Pesticides in Vegetables on Dalian Market by Gas Chromatograph, 2009-10

This paper presents results from surveillance of pesticide multi-residues in vegetables carried out in 2009-10. 420 samples of 10 different types of fresh vegetables were analyzed for their pesticide multi-residue contents using gas chromatograph and NY/T 761-2008 pesticide multi-residue screen methods. The residues exceeded MRLs of forbidden pesticides found were: carbofuran 0.110 mg/kg (kidney bean) and methamidophos 0.037 mg/kg (celery) in January 2009, methamidophos 0.037 mg/kg (tomato) in May 2009, aldicarb 0.013 mg/kg (kidney bean) in September 2009, omethoate 2.200 mg/kg (celery) in November 2009, carbofuran 0.052 mg/kg (green pepper) in April 2010, parathion 0.056 mg/kg (celery) and carbofuran 0.030 mg/kg (celery) in July 2010. Also, chlorpyrifos used as unforbidden pesticide was most frequently found above MRL, rape (0.820 mg/ kg) and celery (0.365 mg/kg) in January 2009, celery (0.330 mg/kg) in May 2009, lettuce (0.298 mg/kg) in September 2009, rape (0.910 mg/kg) in April 2010 and lettuce (0.230 mg/kg) in July 2010. In addition, cypermethrin used as unforbidden pesticide was found above MRL only once in rape (1.270 mg/kg) in May 2009 and none of unforbidden pesticides above MRL was found in November 2009 and January 2010. Most of the samples (96%) were up to the national standard.

Automated multi-filtration cleanup with nitrogen-enriched activated carbon material as pesticide multi-residue analysis method in representative crop commodities

An automated multi-filtration cleanup (Auto m-FC) method with nitrogen-enriched activated carbon material based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. It was applied to pesticide multi-residue analysis in six representative crop commodities. The automatic device was aimed to improve the cleanup efficiency and reduce manual operation workload in cleanup step. By controlling extracts volume, flow rate and Auto m-FC cycles, the device could finish cleanup process accurately. In this work, nitrogen-enriched activated carbon mixed with alternative sorbents and anhydrous magnesium sulfate (MgSO4) was packed in a column for Auto m-FC and followed by liquid chromatography with tandem mass spectrometric (LC–MS/MS) detection. This newly developed carbon material showed excellent cleanup performance. It was validated by analyzing 23 pesticides in six representative matrices spiked at two concentration levels of 10 and 100μg/kg. Water addition volume, salts, sorbents, Auto m-FC procedure including the flow rate and the Auto m-FC cycles for each matrix were optimized. Then, three general Auto m-FC methods were introduced to high water content, high oil and starch content, difficult commodities. Spike recoveries were within 82 and 106% and 1–14% RSD for all analytes in the tested matrices. Matrix-matched calibrations were performed with the coefficients of determination over 0.997 between concentration levels of 10 and 1000μg/kg. The developed method was successfully applied to the determination of pesticide residues in market samples.

Evaluation of MS2 workflows in LC-Q-Orbitrap for pesticide multi-residue methods in fruits and vegetables.

LC-Q-Orbitrap efficiency was evaluated for pesticide multi-residue analysis by using three workflows involving simultaneous MS and MS2 analysis. They were as follows: data-dependent MS2 (dd-MS2), all-ion fragmentation (AIF) and variable data-independent analysis (vDIA). These MS2 workflows were tested for the main method validation parameters such as detection and identification capabilities, repeatability, linear range and quantitation. QuEChER acetonitrile extracts (blanks and spiked with 166 pesticides) of 11 different fruits and vegetables were used for this evaluation. Blank extracts were analysed to evaluate isobaric compounds and potential false identification. Spiked extracts (at 0.01 and 0.1mgkg-1) were analysed to evaluate the false negatives potentially produced (considering a retention mass window of 0.2min). At 0.01mgkg-1, dd-MS2 had the highest identification rate (96-100%, depending on the matrix). In vDIA, it was 86-100% and in AIF 81-100%. But these two last workflows offered more possibilities for applying screening analysis. It was observed that application of the ion ratio criterion established in the SANTE Guidelines for identification can generate some artificial false negative results. It could be overcome by considering a mass error threshold (i.e. 5ppm) as a selected criterion. Detection and quantitation were carried out in full-scan MS. MS2 data were used for identification. Dd-MS2 provided the highest number of points per chromatographic peak, and by that peak area, repeatability was the best (typically <10%). AIF and vDIA were characterised by longer cycle times; thus, the obtained peak area repeatability was slightly worse, but acceptable (<20%). All workflows showed very good linearity in the range 0.01-0.5mgkg-1. The three MS2 workflows were applied to real samples with good results. Graphical abstract LC-Q-Orbitrap was used for pesticide residues analysis in fruit and vegetables. Three approaches to MS2 identificaton were evaluated.

Erratum to: Evaluation of Three Multiresidue Methods for the Determination of Pesticides in Marijuana (Cannabis sativa L.) with Liquid Chromatography-Tandem Mass Spectrometry

Marijuana (non-medical cannabis) is a well-recognized psychoactive herbal drug used for recreational purposes. The aim of this work is to describe and compare the performance and suitability of selected methods to analyze pesticide residues in marijuana. The fitness of three typical pesticide multiresidue methods [acetate buffered QuEChERS (method A), a modified citrate buffered QuEChERS (method B) and citrate buffered QuEChERS (method C)] were tested in marijuana through the LC–MS/MS determination of 61 LC amenable pesticides. Considering recoveries at the highest level for the selected pesticides in marijuana, from the 61 target analytes, 37 (method A), 40 (method B) and 46 (method C) compounds gave accurate results (70–120 % range). Method C showed the best performance for the target analytes in terms of recoveries, precision, limits of quantitation and matrix effect. Marijuana showed to be a highly complex matrix. Most analytes suffered high signal suppression (ME <−50 %) for method B while medium (−50 to 20 %) to low (−20 to 0 %) signal suppression was found for methods A and C. Moreover, high coelution of coextractives with the target analytes was observed. A pilot survey with real samples revealed that seized and legally produced marijuana samples contained pesticides. Residues of diazinon (0.03 mg kg−1), tebuconazole (0.19 mg kg−1) and teflubenzuron (0.11 mg kg−1) were simultaneously detected in one marijuana sample. The establishment of MRLs in a legal consumption scenario such as in Uruguay seems to be necessary in the near future.

The evaluation of matrix effects in pesticide multi-residue methods via matrix fingerprinting using liquid chromatography electrospray high-resolution mass spectrometry

Matrix fingerprinting of twenty-three different commodities was evaluated.

다종 농약 다성분 분석법을 이용한 농산물 중 hexaconzole 분석

농산물 중 hexaconazole 분석을 위해, GC-NPD를 이용하여 다종농약 다성분 분석법을 적용하고자 본 연구를 수행하였다. Hexaconazole의 다종농약 다성분 분석법 유효성 검증은 직선성, 정확성, 정밀성, 검출한계 및 정량한계로 하였다. 0.025~5.0 mg/L의 농도에서 검량선의 상관계수(<TEX>$R^2$</TEX>)는 0.999이상의 우수한 직선성을 보였다. 상추에 0.04~4.0 mg/kg을 첨가한 농약의 회수율은 89.42~94.15%였고, RSD는 7.78%이하의 재현성을 나타냈다. 검출한계는 0.04 mg/kg였고, 정량한계는 0.11 mg/kg였다. 일간 및 일내 정밀도는 각각 2.42~3.49%와 4.90~7.78%였다. 본 연구결과에서 다종농약 다성분 분석법을 이용한 hexaconazole 분석은 매우 정확하고, 높은 재현성을 보여, 농산물 중 hexaconazole 분석에 적용할 수 있을 것으로 판단된다. This work was conducted to apply the multi class pesticide multiresidue method for determining the use of hexaconazole in the agricultural products using GC-NPD. The multi class pesticide multiresidue method results were validated for the assay of hexaconazole by using linearity, accuracy, precision, limit of detection and quantitation. The linearity in the concentration ranged from 0.025 to 5.0 mg/L (<TEX>$R^2$</TEX> > 0.999). Lettuce recoveries ranged from 89.42% to 94.15% with relative standard deviations below 7.78%, for spiking levels from 0.04 to 4.0 mg/kg. The limit of detection was 0.04 mg/kg, and the limit of quantitation was 0.11 mg/kg. The intra- and inter-day precisions were 2.42~3.49% and 4.90~7.78%, respectively. We suggested that the multi class pesticide multiresidue method for determining hexaconazole was highly accurate and reproducible, and it will be used as a routine analysis in agricultural products.

Application of QuEChERS Pesticide Multiresidue Method in Traditional Saudi Medicine and Analysis by Gas Chromatography Mass Spectrometry

Application of QuEChERS Pesticide Multiresidue Method in Traditional Saudi Medicine and Analysis by Gas Chromatography Mass Spectrometry

Optimization and Validation of a Multiresidue Pesticide Method in Rice and Wheat Flour by Modified QuEChERS and GC–MS/MS

An adaptation of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, using ethyl acetate instead of acetonitrile, has been proposed to extract around 100 pesticides in rice and wheat flour. This sensitive and reliable method is based on the use of gas chromatography–tandem mass spectrometry (GC–MS/MS). The method has been validated according to the European Union SANCO/12571/2013 guidelines and ISO 17025:2005. The extraction required a prior water addition, an ethyl acetate extraction of the sample, and a final cleanup step. Calibration curves were linear from 0.003 to 0.150 mg kg−1 for most compounds. The limit of quantification was set at 0.0036 mg kg−1 for more than 80 % of the pesticides. Recoveries were calculated at 0.004 and 0.040 mg kg−1, resulting always in the range 70–116 %, and with precision values ≤20 %. The expanded uncertainty was estimated at the two abovementioned concentrations, being always ≤50 %. The method applicability has been evaluated by the analysis of real samples, and no pesticides were detected above the limit of quantification, although some minor amounts of pesticides were detected (pirimiphos methyl, tebuconazole, chlorpyrifos, and chlorpyrifos methyl) in some of them.

국내 유통 다소비 농산물의 잔류농약 모니터링 및 노출평가

This study was implemented to evaluate food safety on residual pesticides in agricultural products of Korea and to use as a data base for the establishment of food policy. A total of 196 pesticide upon these products were analyzed using multi class pesticide multiresidue methods of Korean Food Code, and 232 samples of 15 agricultural products collected from 9 regions were supplied for this study. In the results, 64 kinds of pesticides were detected in 53 samples, chlorpyrifos and procymidone of them were shown a high frequency of detection in the analyzed pesticides. Among them, two samples (chlorpyrifos in perilla leaves and picoxystrobin in peach) were detected over Maximum Residue Limits (MRLs). The levels of the detected pesticide residues were within safe levels. Also, the intake assessment for pesticide residues including chlorpyrifos at multi pesticide residue monitoring were carried out. The result showed that the ratio of EDI (estimated daily intake) to ADI (acceptable daily intake) was 0.001~0.902% which means that the detected pesticide residues were in a safe range so that residual pesticides in the agricultural products in Korea are properly controlled.

동시 다성분 분석법에 의한 농산물 중 Diflubenzuron 분석

Abstract The multiclass pesticide multiresidue method for the simultaneous determination of diflubenzuronin agricultural products was conducted by using HPLC-UVD. The method was validated through theguidelines of linearity, specificity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precisionwith pesticide-free spinach, Korean cabbage, eggplant, squash, sweet pepper, cucumber, Korean melon. Thecalibration curve of diflubenzuron was linear over the concentration range of 0.05-5 mg/kg with correlationcoefficient of above 0.99999. The limit of detection and quantification was 0.008 and 0.02 mg/kg. Meanrecoveries of diflubenzuron for each sample were 77.5-105.6%. Relative standard deviation (RSD) inrecoveries were all less than 20%. The intra-day and inter-day precision (RSD) were 0.4-1.9% and 0.7-1.9%,respectively. The result of validation indicated that this method was accurate and rapid assay. Key words multiclass pesticide multiresidue method, agricultural products, diflubenzuron, HPLC

Evaluation and validation of an accurate mass screening method for the analysis of pesticides in fruits and vegetables using liquid chromatography–quadrupole-time of flight–mass spectrometry with automated detection

This study reports the development and validation of a screening method for the detection of pesticides in 11 different fruit and vegetable commodities. The method was based on ultra performance liquid chromatography–quadrupole-time of flight–mass spectrometry (UPLC–QTOF–MS). The objective was to validate the method in accordance with the SANCO guidance document (12571/2013) on analytical quality control and validation procedures for pesticide residues analysis in food and feed. Samples were spiked with 199 pesticides, each at two different concentrations (0.01 and 0.05mgkg−1) and extracted using the QuEChERS approach. Extracts were analysed by UPLC–QTOF–MS using generic acquisition parameters. Automated detection and data filtering were performed using the UNIFI™ software and the peaks detected evaluated against a proprietary scientific library containing information for 504 pesticides. The results obtained using different data processing parameters were evaluated for 4378 pesticide/commodities combinations at 0.01 and 0.05mgkg−1. Using mass accuracy (±5ppm) with retention time (±0.2min) and a low response threshold (100 counts) the validated Screening Detection Limits (SDLs) were 0.01mgkg−1 and 0.05mgkg−1 for 57% and 79% of the compounds tested, respectively, with an average of 10 false detects per sample analysis. Excluding the most complex matrices (onion and leek) the detection rates increased to 69% and 87%, respectively. The use of additional parameters such as isotopic pattern and fragmentation information further reduced the number of false detects but compromised the detection rates, particularly at lower residue concentrations. The challenges associated with the validation and subsequent implementation of a pesticide multi-residue screening method are also discussed.