Occurrence and trends of fluorinated pesticides in food commodities marketed in Luxembourg (2011–2024)

The samples of greenhouse cucumbers were collected from the Central Fruit and Vegetable Market of Tabriz between June and December 2017. In the twenty-four cucumber samples (unwashed, washed, peeled), the residue of 18 organophosphates pesticides (OPPs) was analyzed using gas chromatography-mass spectrometry (GC-MS) following the modified QuEChERS method (quick, easy, cheap, effective, rugged and safe). Chronic non-carcinogenic risk assessment from pesticide residues in the samples was also performed for age groups of adults (women and men) and children using the Monte Carlo Simulation (MCS). Amongst the eighteen studied pesticides, eight pesticides including dimethoate, diazinon, methyl parathion, fenitrothion, chlorpyrifos, profenofos, ethion, and azinphos-methyl were detected. Pesticide residues were detected in 100% of unwashed, washed and peeled samples in the range of 0.08 to 0.37 mg.kg-1, 0.03 to 0.17 mg.kg-1 and 0.01 to 0.08 mg.kg-1, respectively. The maximum and minimum values were found for diazinon pesticides with 0.37 mg.kg-1 and profenofos and fenitrothion with 0.01 mg.kg-1. 100 % of samples contained at least three pesticide residues (dimethoate, diazinon, and methyl parathion), while 87.5% of the samples contained more pesticides residues. The residues of dimethoate, diazinon, and methyl parathion were above Maximum Residue Limits (MRL) in 100%, 83.33%, and 66.66% of samples, respectively. The identified residues were more than the EU MRLs and the IR MRLs in 100% and 95.83% samples, respectively. The mean reduction of pesticide residues in the washed and peeled samples was in the range of 37.74 to 56.52% and 66.66 to 92.30%, respectively. According to the performed risk assessment, there is no significant non-carcinogenic health risk due to the consumption of cucumber for the age group of adults. Hence, there is a considerable non-carcinogenic health risk to children due to the consumption of unwashed (HI = 2.22) and water-washed (HI = 1.36) greenhouse cucumbers.

This study was conducted to monitor and evaluate the health risks of multiple organophosphorus pesticide residues in three characteristic fruits of Maragheh district, East Azerbaijan province. The Monte Carlo method was used to quantify the possible non-carcinogenic health risks associated with pesticide residues in adults and children. The residues of 17 pesticides in 36 samples were analysed using the QuEChERS extraction method coupled with gas chromatography-mass spectrometry (GC/MS). Residues of 13 pesticides (76.47%) were detected in grape samples and 15 pesticides (88.23%) in apricot and plum samples. The maximum level found in grape samples was due to chlorpyrifos with 1.2 mg/kg, and in apricot and plum samples to diazinon with 1.6 and 1.3 mg/kg, respectively. All grape, apricot and plum samples contained at least ten pesticides with levels exceeding the Iranian and EU Maximum Residue Limits (MRLs). The processing factor for washing treatment in grape, apricot and plum samples was less than 1, ranging from 0.53 to 0.69. Chlorpyrifos with values of 0.064 and 0.256 in the grape samples and diazinon with values of 0.0443 and 0.177 in the apricot samples and values of 0.0263 and 0.105 in the plum samples contain the highest hazard quotients (HQ) for adults and children, respectively. The cumulative risk assessment due to exposure to several pesticide residues suggests that there is no significant health risk for adults (HI < 1). However, consumption of unwashed grapes may cause adverse effects in children (HI = 1.48). However, for further research, a comprehensive longitudinal study is suggested to assess the long-term effects of exposure to pesticides especially for children.

Influence of On-farm Pesticide Practices and Processing Methods on Pesticide Residue Levels in Potato Tubers (Solanum tuberosum L.) in Nyandarua County, Kenya.

Three green leafy vegetable samples of pumpkin leaves, spinach leaves, and sorrel leaves were collected from three different locations in a farm in Akwanga and were tested for the presence of organophosphorus (OP) compounds. The concentrations of all the pesticide residues in the vegetable samples were determined using gas chromatography with mass spectrometry (GC-MS). The organophosphorus pesticides detected include carbaryl (0.052 mg/kg) in pumpkin, this is below European maximum residues limit (EU MRL) of 0.1 mg/kg, Dimethoate was found in pumpkin (0.165 mg/kg), spinach (0.103 mg/kg) and sorrel (0.250 mg/kg) all above the EU MRL of 0.05 mg/kg. Dichlofenthion was detected in pumpkin (0.308 mg/kg), pirimiphos methyl was detected in pumpkin and spinach (0.428 mg/kg and 0.149 mg/kg respectively), all these were below the EU MRL of 0.5 mg/kg. Chlorpyrifos was found in spinach (0.230 mg/kg) and sorrel (0.192 mg/kg) only spinach was above the EU MRL of 0.2 mg/kg. The pesticide residue Bromophosethyl was detected in all vegetables, pumpkin leaves (0.501 mg/kg), sorrel (1.571 mg/kg) and spinach (7.981 mg/kg) all above the EU MRL of 0.5 mg/kg. The remaining pesticides detected were all below their EU MRL value; these are Ethion found in spinach (0.167 mg/kg), Methyl Parathion in spinach (0.103 mg/kg) and sorrel (0.335 mg/kg). The levels of some of the organophosphorus pesticide residues found in vegetables were above the maximum residue limits (MRLs) set by the European Union. This calls for laws to regulate the use and circulation of such chemicals. Based on the observation made in these studies, it is proposed that more extensive monitoring investigation covering all vegetables part in Akwanga Nasarawa state be carried out to find the exact position of pesticide residues.

Description of the subject. The real-time management of residues of plant protection products is a general issue for food producers and/or exporters. Authorized pesticides under European Regulation (EC) No 1107/2009 (Reg. 1107/2009) are granted a maximum residue limit (MRL) defined by the European Chemicals Agency (ECHA). These maximum residue limits are managed by the European Commission and listed in EC Regulation No 396/2005. MRLs for newly approved substances are set for pesticide residues present in products or groups of products covered by Annex I with a default value of 0.01 mg·kg-1, unless they have been considered, elaborated upon on approval and affected in one of the six other Annexes (II to VII). Substances listed in Annex IV are favoured in the selection of substances to be used by producers as it is for substances with very low potential impacts (low-risk substances [Art. 22 of Reg. 1107/2009] which therefore require no MRL; basic substances [Art. 23 of Reg. 1107/2009]; and microorganisms). The number of substances affected by this lack of an MRL (without residues survey requirement) has been steadily increasing since the publication of the SANCO/11188/2013 Guideline. Many biocontrol agents are listed in Annex IV, including microbial insecticides (e.g. Bacillus thuringiensis, Cydia pomonella granulosis virus), semiochemicals used in traps (e.g. ammonium acetate, putrescine) and some natural substances (e.g. sulphur) as well as all the currently listed basic substances. Objectives. To show that plant protection may be achieved with less concern or control (auto + external) than with certain agrochemical pesticides, including those without maximum residue limits (MRL). Method. Analysis of EU Pesticide Database and EU Regulation (EU) No 540/2011. Results. All approved pesticide active substances with no MRL included in Annex IV of Regulation (EC) No 396/2005, listed by substance status type (active, low-risk or basic) and category (microorganism, semiochemical or natural). Conclusions. These results may be used to help achieve plant protection with much less risk of contaminations, while noting the necessity for controls, analytical issues, positive controls, as well as the possibility of downgrading and withdrawal of approval from the market.

Indole-3-acetic acid (IAA) is a natural plant hormone which can also be used as a plant growth regulator. However, its usage on crops is not permitted in the EU, with a maximum residue limit (MRL) currently set at 0.1 mg kg−1 for all food commodities. As available data on the occurrence of IAA in food commodities are limited, this work aims at evaluating the amount of IAA in important food commodities such as coffee and cereals, but also selected processed ingredients such as cocoa and malt. In total, 133 samples representing 18 different food commodities were analysed for the occurrence of free IAA using a liquid chromatography high resolution mass spectrometry method. IAA was detected in all samples except malt powders and tomatoes. The analysed crops were either grown under conventional, organic, or strictly controlled (i.e. excluding the use of IAA as pesticide/plant growth regulator) farming conditions. No significant differences in the amounts of IAA were found in crops grown under the three different farming conditions. A high percentage of the samples (63%) showed levels of free IAA above the EU MRL. We therefore conclude that the natural abundance of IAA was not properly assessed prior to the establishment of some current EU MRLs. Based on the natural occurrence of IAA in a wide range of foods; we question the need for an MRL for IAA in plant-based foods.

An optimised version of the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for simultaneous determination of 14 organochlorine pesticides in carrots was developed using gas chromatography coupled with electron-capture detector (GC-ECD) and confirmation by gas chromatography tandem mass spectrometry (GC-MS/MS). A citrate-buffered version of QuEChERS was applied for the extraction of the organochlorine pesticides, and for the extract clean-up, primary secondary amine, octadecyl-bonded silica (C18), magnesium sulphate (MgSO4) and graphitized carbon black were used as sorbents. The GC-ECD determination of the target compounds was achieved in less than 20 min. The limits of detection were below the EU maximum residue limits (MRLs) for carrots, 10–50 μg kg−1, while the limit of quantification did exceed 10 μg kg−1 for hexachlorobenzene (HCB). The introduction of a sonication step was shown to improve the recoveries. The overall average recoveries in carrots, at the four tested levels (60, 80, 100 and 140 μg kg−1), ranged from 66 to 111 % with relative standard deviations in the range of 2–15 % (n = 3) for all analytes, with the exception of HCB. The method has been applied to the analysis of 21 carrot samples from different Portuguese regions, and β-HCH was the pesticide most frequently found, with concentrations oscillating between less than the limit of quantification to 14.6 μg kg−1. Only one sample had a pesticide residue (β-HCH) above the MRL, 14.6 μg kg−1. This methodology combines the advantages of both QuEChERS and GC-ECD, producing a very rapid, sensitive and reliable procedure which can be applied in routine analytical laboratories.

An LC-MS/MS method was developed for determination and confirmation of tilmicosin in bovine, swine, chicken, and turkey tissues (liver, kidney, muscle, and skin/fat) and bovine milk. The method was subjected to single-laboratory validation to establish method performance parameters. Animal tissues and bovine milk were fortified at four concentrations ranging from 0.5 times the lowest maximum residue limit (MRL) or tolerance to 2 times the highest MRL or tolerance considering the Codex and EU MRLs and the US tolerances in the various tissues and milk studied. Incurred tissues were analyzed to verify the precision of the method. The data demonstrated linearity of matrix-matched calibration curves using a weighted (1/×) regression. Recoveries varied from 83.3 to 107.1%. Repeatability precision (RSDr) ranged from 0.465 to 13.4% and intermediate precision (RSDi) ranged from 2.24 to 14.7% in fortified tissue. Repeatability of the method was verified in incurred tissues, ranging from 3.41 to 16.0%. The limits of detection and quantitation of the method are presented and vary by matrix. One confirmatory transition ion was examined across all matrixes and met US and EU criteria for mass spectrometry confirmation. The method was shown to be robust when small changes in method parameters were made, and stability of the analyte in fortified tissues, extracts, standard solutions, and matrix-matched standards was estimated. The data satisfy the requirements of the AOAC Stakeholder Panel for Veterinary Drug Residue Methods for single-laboratory validation studies and the U.S. Food and Drug Administration Center for Veterinary Medicine Guidance for Industry #208 (VICH GL49). The LC-MS/MS method was demonstrated to be suitable for determination and confirmation of tilmicosin residues in bovine, swine, chicken, and turkey tissues and bovine milk based on Codex and EU MRLs and US tolerances.

Contamination levels of organophosphorus and synthetic pyrethroid pesticides in vegetables marketed in Accra, Ghana

This study analyzed 5731 Egyptian onion samples collected from 2021 to 2024 to detect 430 pesticide residues and evaluate occurrence patterns, EU Maximum Residue Limits (MRLs) compliance, multiple residue prevalence, and consumer health implications. The analysis revealed temporal fluctuations in contamination, with residue-free samples ranging from 51.19% (2023) to 75.59% (2022) and MRL exceedances varying from 1.34% (2022) to 8.33% (2023). Throughout 2021–2024, fungicides dominated pesticide residues, declining from 70% to 50%, while insecticides increased from 30% to 40%. Pesticide detection patterns shifted significantly over the study period, with carbendazim decreasing from 20.99% to 2.35%, azoxystrobin fluctuating between 3.86% and 18.78%, and dimethomorph rising to 16.67%, reflecting evolving agricultural practices. Multiple residue occurrence fluctuated dramatically, from 9.76% (2022) to a peak of 30.82% (2023), while single residue occurrence remained more stable, ranging between 14.06% and 22.90%. Several pesticides exceeded EU MRLs, including imazalil, chlorpropham, chlorpyrifos, imidacloprid, and profenofos. Despite these violations, the EFSA PRIMo 3.1 model’s chronic risk assessment showed that exposure levels for all population groups remained well below Acceptable Daily Intake (ADI) thresholds, with a maximum %ADI of 2.27% for chlorpyrifos in high-consumption regions.

An improved microbiological screening assay is reported for the detection of quinolone residues in poultry muscle and eggs. The method was validated using fortified tissue samples and is the first microbial assay to effectively detect enrofloxacin, difloxacin, danofloxacin, as well as flumequine and oxolinic acid, at or below their EU maximum residue limits (MRL). The accuracy of the assay was shown by analysing incurred tissue samples containing residue levels around the MRL. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) quantification of the quinolone concentration in these samples showed that the test plate can be used semi-quantitatively, allowing the definition of an “action level” as an inhibition zone above which a sample can be considered “suspect”. The presented assay is a useful improvement or addition to existing screening systems.

The development of an analytical method for the determination of four selected pyrethroid insecticides at residue level in beef meat is presented. Acetone and petroleum ether at 40-60 degrees C were chosen as extraction solvents. A two-step clean-up was performed using an Extrelut NT3-C(18) system followed by a Florisil column, with disposable, ready-to-use cartridges. Instrumental analysis was carried out on a gas chromatograph equipped with an electron capture detector (GC-ECD), using matrix-matched and internal standard calibration techniques. Confirmatory analysis by GC-MS was performed. Recoveries at the EU Maximum Residue Limit (MRL), 0.5 x MRL and 1.5 x MRL levels and the repeatabilities were widely satisfactory. The main advantage of the method was the reduction of analysis time as compared with previously published works. The applicability of the method to different matrices and pesticide classes will be investigated.

Analysis of pesticide residues in bananas harvested in the Canary Islands (Spain)

A multiresidue method without cleanup step was validated for simultaneous determination of multiclass pesticide residues in rice. The extracted incurred residues of pesticides were separated on a reversed-phase column and quantified by tandem mass spectrometry (MS/MS). The method accuracy was in the range of 71–108%, and the precision was in the range of 4–20% for 25 out of 28 selected pesticides. The method quantification limits for 25 selected pesticides were below Codex and EU maximum residue limits (MRL). The selected 25 pesticides met the EU-SANTE and FAO/WHO Codex Alimentarius Commission method validation guidelines. The interday repeatability of the optimized method was between 4 and 18% (n = 6). The expanded uncertainty calculated for the optimized method ranged from 22 to 48%. The results obtained demonstrated the method's suitability for routine analysis. In total, 35 samples were analyzed of which, 22 samples (62%) were found to be contaminated with pesticides concentrations ranging from 0.010 to 0.297 mgkg−1.

This study investigated the prevalence of 430 pesticide residues in 9963 samples representing 20 types of medicinal and aromatic plants (MAPs) from Egyptian markets using GC-MS/MS and LC-MS/MS. Pesticide-free samples ranged from a high of 68.33% in rosemary and 64.52% in hibiscus to a low of 9.70% in sage and 9.43% in calendula. Compliance with EU maximum residue limits (MRLs) was highest in calendula (84.18%), thyme (81.09%), and oregano (79.23%), but lowest in rosemary (31.38%) and hibiscus (34.66%). Exceedances of MRLs were most notable in sage (10.97%), moringa (8.57%), and cumin (7.80%). Chlorpyrifos dominated as the most frequently detected pesticide across all plants, with detection rates of 16–88%, followed by metalaxyl (detected in 14 plants with detection rates from 1.84% to 36.55%) and pendimethalin (found in 13 plants with detection rates from 2.27% to 19.91%). Single residue prevalence was highest in calendula (59.93%), camomile (57.05%) and dill (52.30%), whereas multiple residues were more common in oregano (50.77%), marjoram (49.52%) and sage (48.95%). The most common co-occurring pesticide combinations were chlorpyrifos with profenofos (16 out of 20 plant types), metalaxyl (15 out of 20 plant types) or atrazine (11 out of 20 plant types). These findings underscore the need for stricter pesticide monitoring, regulation, and sustainable agricultural practices to ensure the safety of these widely consumed plants.