Assessing washing methods for reduction of pesticide residues in Capia pepper with LC-MS/MS

Occurrence, dissipation and processing factors of multi-pesticides in goji berry

As medicine and food homology substance, goji berry is consumed worldwide in the form of fresh, dried and juice; however, pesticide residues have become one of the problems that essentially threaten its quality during cultivation and processing. In this study, a total of 75 dried goji berries were sampled from markets across China, and for the determination of 62 analytes, 28 pesticides were identified. Nine pesticides with high detectable rates and residual levels were selected for folia spraying, and their half-lives were found to range from 1.04 to 2.21 d. The processing factors (PFs) of juice were between 0.25 and 1.02, and this was mainly related with their octanol-water partition coefficient (logKow values). Washing could reduce pesticides residues to varying degrees with the removal rates between 17.00% and 74.05%. Sun drying with higher PF values in the range of 0.61-5.91 exhibited more obvious enrichment effect compared to oven drying. Commercial goji berry had cumulative chronic dietary risks with the hazard index (HI) values of 1.61%-4.97%. Its acute risk quotients (HQas) for consumers were 543.32%-585.92% and were mainly due to insecticides. These results provide important references for rationalizing pesticide application during goji berry cultivation and for the improvement of process to ensure food safety.

Occurrence and health risk estimate of organochlorine pesticides in fruits and vegetables matrices

Occurrence of 20 organochlorine pesticides (OCPs) in 60 organic and non-organic fruits and vegetables matrices was undertaken using QuEChERS Method EN 15662 for sample preparation analyzed by gas chromatography-mass spectrometry (GC-MS/MS). The procedural method was validated by spiking the OCP standard solutions at three fortified levels at 10, 50, and 100 µg/kg wet weight (ww) to the real matrix of fruit and vegetable with good recovery ranging from 75 to 108% with relative standard deviation (RSD) ≤ 11%, and the limits of detection and quantification (LODs and LOQs) were 0.002-0.02 μg/kg and 0.004-0.1 μg/kg ww, respectively. The assessment of health risks associated with pesticide residues through consumption of vegetables and fruits and the effect of washing and peeling on concentration of various pesticides were also studied. The results showed that the concentration levels of 60% of samples were lower than the LOQs, while the rest was contaminated by OCP residues. Organic fruits and vegetables showed the absence of OCPs, while several of the studied compounds were detected from conventional agriculture. Skin removal (peeling) was the most effective strategy to eliminate or decrease pesticide residues, and should be one of the solutions to reduce the health impact of pesticides in fruits and vegetables. The analysis of health risk assessment was based on the use of the estimated average daily intake (EDI), hazard index (HI), and hazard ratio (HR) for individuals in two weight categories: children (weighing 16.7 kg) and adults (weighing 60 kg). The HI values were less than 1 suggesting that there was no probable non-carcinogenic health effect, except for heptachlor for children (HI of 1.285). However, the values of HR revealed that children were more susceptible to the carcinogenic health effect associated with consuming contaminated vegetables.

Determination of pesticide residues in varieties of pepper sold at different periods and provinces in Turkey and investigation of their adverse effects on human health and the environment

Pesticides are dangerous chemicals that can harm to people and the environment when applied inappropriately or in excess. In this research, various pesticide residues were investigated in 48 pepper samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples were collected randomly in two periods of time (September and December) from markets and greengrocers in four provinces (Siirt, Mardin, Diyarbakir, and Batman). Considering the means of the first and second periods, diclofop-methyl had the highest concentration of 29.4 ± 7.7 µg kg-1, and diazinon had the lowest of 21.1 ± 4.6 µg kg-1. Based on the maximum residue limits (MRLs) of pesticides specified in the Turkish Food Codex, pyrimethanil, bupirimate, and diclofop-methyl were found to be below the maximum acceptable residue limit, while pyridaphention, dinoseb, diazinon, and pirimiphos-methyl were found to be above the limit. Thus, the current study demonstrated the potential of LC-MS/MS as a crucial technique for accurate measurements and confirmations of pesticides in different pepper varieties.

Herbicide contamination of Batak plain agricultural soils and risk assessment

Herbicide residue levels were analyzed in agricultural soils of Batak plain and health risk assessments were made for relevant pesticides. Herbicide contamination levels were analyzed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure. Herbicide-free soil samples were spiked at two different levels. Overall recovery of the method was 87.32%. Present findings were parallel to SANTE recovery limits. About 50% of collected samples from the study sites contained herbicides at different concentrations. Totally, eight herbicides were detected, and herbicide concentrations ranged between 1.085 and 1724.23 μg kg-1. Metolachlor had the highest concentration (1724.23 μg kg-1) in a sample taken close to the pesticide waste disposal area. Six herbicides were detected at different concentrations in the same sample. Persistent herbicides (terbuthylazine and pendimethalin) were detected in 35 samples. Risk assessments revealed that hazard index (HI) and hazard quotient (HQ) were less than 1. The greatest HQ values were identified for terbuthylazine as 2772.48 × 10-7 and 20793.61 × 10-7 for adults and children, respectively. The HI for all herbicides were 3916.05 × 10-7 for adult and 29370.39 × 10-7 for children.

Residue behaviors of six pesticides during apple juice production and storage

The residue behaviors of carbendazim, thiamethoxam, imidacloprid, acetamiprid, prochloraz, and difenoconazole during the production and accelerated storage of apple clear and cloudy juice was systemically evaluated. The pesticides were determined by liquid chromatography-mass spectrometry (LC-MS/MS) after each processing step and at different storage times. The results indicated that the different processing steps in the apple clear and cloudy juices production have different effects on the reduction of pesticide residues. The pre-processing steps including washing and pressing reduced the pesticide residues significantly by 36.8 % to 67.9 % and 32.9 % to 89.8 %, respectively, mainly due to the water solubility and log Kow of pesticides. The enzymation step in clear juice production slightly reduced six pesticide residues from 1.9 % to 31.6 %, and the filtration step after clarification and purification decreased the pesticide residues from 14.0 % to 87.5 % with no significance, while prochloraz was not detected. The centrifugation step in cloudy juice production reduced the pesticide residues from 6.3 % to 88.9 %. The pasteurization step in clear and cloudy juice production lowered the pesticide residues slightly on account of the short heating time of 30 s. The accelerated storage of clear and cloudy juices was effective in the reduction of pesticide residue levels. The processing factors (PFs) in the whole process of clear and cloudy juice production were equal to or lower than 0.2, especially for prochloraz and difenoconazole, illustrating that apple juice production could decrease the pesticide residues greatly. The results will provide important references to predict the levels of pesticide residues in apple juice during processing and storage. Meanwhile, the PFs identified in the study could be helpful in the risk assessment of pesticides in apple juice.

Evaluation of convolutional neural network for non-destructive detection of imidacloprid and acetamiprid residues in chili pepper (Capsicum frutescens L.) based on visible near-infrared spectroscopy

Consumption of agricultural products with pesticide residue is risky and can negatively affect health. This study proposed a nondestructive method of detecting pesticide residues in chili pepper based on the combination of visible and near-infrared (VIS/NIR) spectroscopy (400-2498 nm) and deep learning modeling. The obtained spectra of chili peppers with two types of pesticide residues (acetamiprid and imidacloprid) were analyzed using a one-dimensional convolutional neural network (1D-CNN). Compared with the commonly used partial least squares regression model, the 1D-CNN approach yielded higher prediction accuracy, with a root mean square error of calibration of 0.23 and 0.28 mg/kg and a root mean square error of prediction of 0.55 and 0.49 mg/kg for the acetamiprid and imidacloprid data sets, respectively. Overall, the results indicate that the combination of the 1D-CNN model and VIS/NIR spectroscopy is a promising nondestructive method of identifying pesticide residues in chili pepper.

Dissipation of Four Typical Insecticides on Strawberries and Effects of Different Household Washing Methods

The dissipation patterns of chlorfenapyr, cyenopyrafen, indoxacarb, and spirotetramat on strawberries and the effects of different household washing methods were investigated. A risk assessment was also conducted by monitoring the insecticide residues detected. The concentrations ranged from 0.011 to 0.27 mg/kg for chlorfenapyr, 0.064 to 0.99 mg/kg for cyenopyrafen, 0.042 to 0.53 mg/kg for indoxacarb, and from 0.25 to 1.3 mg/kg for spirotetramat, which were all below the maximum residue limits (MRLs) reported. Soaking the fruit in solution and then rinsing with running water (B) led to better residue removal (40.9 ± 23.7%) than only soaking in solution (A) (24.7 ± 22.5%). However, neither method decreased chlorfenapyr concentrations, suggesting that the physical–chemical properties of chlorfenapyr could also affect its removal on strawberries. Regarding the different washing solutions in method B, 3% vinegar (removal efficiency: 48.7%) and 3% salt (45.7%) were the most efficient, followed by 3% green tea (38.9%), and tap water only (24.6%). Additionally, the estimated risk quotients (RQs) for strawberry consumption for women were about 1.5 times higher than those observed for men, but both were lower than 1, suggesting minimal risk to humans.

Removal of pesticide residues from apple and tomato cuticle

Pesticide residues are always an unsolved problem in the world despite all kinds of prevention measures. The present research work is based on a scientific hypothesis, i.e., "The removal of average pesticide residue is inversely proportional to the thickness of cuticle." The effects of boron-containing products and plant-based surfactants were tested for the removal of five pesticides (lambda-cyhalothrin, chlorpyrifos, diflubenzuron, metaflumizone, acetamiprid) on tomatoes and apples. Boron-containing products were able to remove the pesticide residues on average between 58.0 and 72.6% in tomatoes and 33.2-58.8% in an apple. While plant-based surfactants removed residues on average between 58.5 and 66.6% in tomatoes and 41.0-53.2% in an apple. The highest removal rate was 72% with etidot at 1%. The solution of 1% C8-C10 provided 66.6% average removal for tomatoes. Less removal was achieved in apples. For an apple, Log K_ow and molecular mass (independent variables) were significant with p < 0.01, and the coefficient of determination (R²) was > 0.87. However, the multiple linear regression analysis for ground colemanite was significant with R² of 0.96. In tomatoes, neither Log K_ow nor molecular mass as significant. The correlation was found between the physical and chemical properties of pesticides, but it is estimated that the thickness of the cuticle is effective in removing pesticides.

Pesticide Residues and Effect of Household Processing in Commonly Consumed Vegetables in Jimma Zone, Southwest Ethiopia

The long-term and indiscriminate use of pesticides has resulted in serious health effects. Aside from that, developing countries do not have any monitoring systems in place to prevent the consumption of high levels of pesticides in foods. Therefore, this study aimed to determine pesticide residues and the effect of processing in commonly consumed vegetables in the southwestern part of Ethiopia. In total, 12 samples of 1 kg of each type of vegetable were collected from selected markets. Moreover, as a solution to pesticide residue problems in vegetables, the effect of different processing methods such as washing, peeling, boiling, and their cumulative effect was studied. In the analytical procedure, the modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction with florisil as a cleanup sorbent was used and the identification of pesticides was done by using gas chromatography with an electron capture detector (GC-ECD). The parent p,p'-DDT was detected at a concentration of 0.015 mg/kg in potato samples from the Serbo market and a concentration of 0.516, 0.232, 0.174, and 1.512 mg/kg in Merkato, Kochi, Serbo, and Shebe onion samples, respectively. P`p-DDT is detected at a high concentration compared to its metabolites (p,p'-DDE and p,p'-DDD), which is an indication of recent use. DDT and its metabolites, other organochlorines (lindane, γ-chlordane, dimethachlor, and heptachlor), and pyrethroids (cypermethrin and deltamethrin) exceeded the recommended limits by FAO and WHO in multiple samples of potato, onion, and cabbage. The processing result showed that washing, boiling, and the combination of the two revealed a 100% reduction in o,p'-DDT, and p,p'-DDT pesticides detected in cabbage. In conclusion, multiple residues were detected in the three vegetables studied, indicating that pesticides were applied intensively. Pesticide levels were reduced by home processing procedures, which is important for consumer safety.

The Effect of Household Food Processing on Pesticide Residues in Oranges (Citrus sinensis)

In this study, the effect of various household food-processing methods (washing, peeling, processing into jam and fruit juice, freezing, storage) on pesticide residues (abamectin, buprofezin, ethoxazole, imazalil, and thiophanate-methyl) in oranges was investigated. Residue analyses were performed by quick-easy-cheap-efficient-rugged-safe (QuEChERS) extraction and liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS) analysis. The limit of quantification of the method for each pesticide was 10 µg/kg. Physicochemical properties of the pesticides and the type of the food process had a considerable effect on the fate of pesticide residue. Pesticide residues were mostly dispersed on orange peels and washing with tap water decreased the residue levels by 26-84%. The amount of residue in oranges was reduced by 63-100% during fruit juice processing, while residues were removed by 90-100% after jam processing. Pesticides with a high octanol-water coefficient were absorbed by the wax of the orange peel, therefore they remained on the peel and could not easily be removed by washing. Moreover, pesticides with lower water solubility did not diffuse easily through the fruit juices from the pulp section of the fruit. The processing factor was greater than 1 for the separation of the orange peel and less than 1 for the washing step and jam and fruit juice productions.

Effects of Household Processing on Residues of the Chiral Fungicide Mandipropamid in Four Common Vegetables

The study aimed to detect the content of mandipropamid enantiomers in unprocessed and processed tomato, cucumber, Chinese cabbage, and cowpea samples and assess the health risks to Chinese consumers. Data showed that washing and soaking with an acidic solution reduced the mandipropamid residue from vegetable samples by 54.1-82.2%. The pickling process resulted in a 6.2-65.2% loss of mandipropamid from cucumber, Chinese cabbage, and cowpea samples. Peeling and juicing were the best removing techniques for mandipropamid residues in tomato and cucumber (removal rate (RR) value > 91%), and cooking for 5 min could effectively reduce the levels of mandipropamid in Chinese cabbage and cowpea (RR values of 81.4-99.7%). The values of processing factor for the processed vegetable samples are all less than one. No significant enantioselectivity of mandipropamid was found in the vegetables during processing. Health risk data showed that samples of four types of mandipropamid-contaminated vegetables were safe for consumption after processing.

Monitoring of pesticide residues in peppers from Çanakkale (Turkey) public market using QuEChERS method and LC-MS/MS and GC-MS/MS detection

Residue analyses were conducted for 283 pesticide active ingredients on pepper samples collected from the local markets (between April and November) of Çanakkale province of Turkey by using QuEChERS method and LC-MS/MS and GC-MS/MS devices. In present pepper samples, 35 different pesticide residues were detected. About 25.0% (27 samples) of present samples had single residue and 43.5% (47 samples) had multiple residues. Of the detected pesticides, acetamiprid, triadimenol, imidacloprid, boscalid, pirimiphos-methyl, tebuconazole, and metalaxyl were the most common ones, while carbendazim/benomyl, fenpropathrin, and thiram were the banned ones. Moreover, 24 of the pesticide residues detected were above the MRL values, 19 pesticides were in the "moderately hazardous (II)," and two pesticides were in the "extremely hazardous (Ib)" class (WHO). Present findings revealed that consumer health may be in danger despite all legal measures by the Ministry of Agriculture and Forestry of Turkey, thus greater emphasis should be put on monitoring of pesticide use and residues.

Investigation of pesticide residues in peach and nectarine sampled from Çanakkale, Turkey, and consumer dietary risk assessment

The present study was conducted to investigate pesticide residues on peach and nectarine. For method verification, samples were spiked at 0.1, 1.0, and 10.0 times of maximum residue limit (MRL) for each pesticide. The Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry detection revealed that limit of quantifications (LOQs) of pesticides were below the MRL. The overall recovery was 113.51% with relative standard deviation (RSD) of 17.33% for peach and 113.61% with RSD of 11.44% for nectarine. These figures were within the Directorate-General for Health and Food Safety (SANTE) recovery limits (60-140%) and the values specified for the repeatability (RSD ≤ 20%). Samples were collected from 5 different stands at Çanakkale open markets for 12 weeks. None of the residues was not ≥ MRL in any samples. Maximum levels of 567.80 and 322.10 μg/kg boscalid were detected in peach and nectarine, respectively, corresponding approximately 1/10 and 1/15 of the MRL. Maximum levels for tebuconazole were about 1/12 and 1/10 of the MRL for peach (47.53 μg/kg) and nectarine (56.90 μg/kg), respectively. Chlorpyrifos residues of all samples were below LOQ. According to our findings and the World Health Organisation Guideline, chronic exposure levels of pesticides were low and there is no risk to human health in terms of 3 pesticides.

Screening of multiclass pesticide residues in maca and Moringa oleifera by a modified QuEChERS sample preparation procedure and UPLC-ESI-MS/MS analysis

In the present study, a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method was proposed for the simultaneous analysis of 75 pesticides in maca and Moringa oleifera with ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS). The developed method was validated in accordance with linearity, linear range, limit of detection, limit of quantification, accuracy, precision, and matrix effect. Each analyte had good linearity (R² > 0.99) in the corresponding concentration range. The method LOD and LOQ values of all the analytes ranged from 0.01 μg kg⁻¹ to 303.35 μg kg⁻¹ and 0.03 μg kg⁻¹ to 1011.15 μg kg⁻¹, respectively. The recoveries (n = 6) of the analyzed pesticides were in the range of 75.92–113.43%. The RSDs of precision were between 0.60% and 7.36%. All matrix effect values ranged from 81.79% to 118.71% and 80.36% to 119.64% in maca and Moringa oleifera, respectively. The analysis of 103 samples showed the presence of isofenphos-methyl in some of them. The method had a good application prospect and could be used as a general approach for the quantitative determination of pesticide residues in food.

In the present study, a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method was proposed for the simultaneous analysis of 75 pesticides in maca and Moringa oleifera with UPLC-ESI-MS/MS.