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Background When previous studies were examined, it was reported that a wide variety of pesticide residues were detected in lettuce (Bakırcı et al. in Food Chem 160:379–392, 2014; Balkan and Yılmaz in Food Chem 384:132516, 2022; Qin et al. in Food Res Int 72:161–167, 2015; Selim et al. in Res J Environ Sci 5:248–258, 2011). In addition, pesticide-contaminated lettuce poses a risk to consumers as it is a fresh food that is eaten raw. Therefore, pesticide removal processes must be applied before consumption. Some pesticide removal process, such as storage and heat treatment cannot be applied to lettuce because of unshelled, no long shelf life and consuming as fresh. Different practical methods are needed for the removal of pesticides process. The recommendations of suitable methods for cleaning salad materials in ready-to-eat sector, hotels, restaurants and homes are very important. It is important to reduce pesticide residues in vegetables and fruits that are consumed raw by washing them with non-toxic solutions. These approaches aim to protect public health. The study conducted in 2021 determined the effect of various washing treatments. For this purpose, before the washing trials, QuEChERS method was validated for determination of 7 pesticides in lettuce, by liquid chromatography–tandem mass spectrometry (LC–MS/MS). Lettuce plants were grown in the greenhouse for the study. Lettuces were brought to the laboratory 24 h after pesticides were applied in the greenhouse. The samples were kept in 2 L washing solution for pesticide analysis. Results The processing factor values of all washing applications were found below 1. This result shows that the residue level was reduced by washing solutions. Among the washing solution treatments, the rice vinegar washing solution was found to be most effective in reducing the pesticide residues which was due to the high degree in the pesticide degradation. Washing with filtered rice water also exhibited equivalent reduction capability similar to rice vinegar. Conclusions The effectiveness of washing solutions was different for boscalid, deltamethrin, fluopcolide, fluopyram, pyrimethanil, pyraclostrobin and sulfoxaflor. However, when the average removal of these pesticides was evaluated, the most effective solutions were rice vinegar, filtered rice water, carbonated water, NaCl + grape vinegar, hot tap water (40 °C), grape vinegar (6% acetic acid), grape vinegar + water, cold tap water (20 °C), lemon juice, baking soda water, grape vinegar (8% acetic acid), filtered mint water and grape vinegar (4% acetic acid), respectively. It was concluded that some of the solutions used in this study can significantly reduce exposure to pesticides for consumers.

Insecticide, acaricide, nematicide and metabolite residues were assayed in 104 potato samples collected from local markets in Tokat, Türkiye in 2022 and the potential health risk for consumers assessed. Analytical method verification was performed for 135 pesticide active substances in potato matrices by liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry. Matrix-matched calibration curves were constructed and good linearity was obtained with a coefficient of determination between 0.990 and 0.999. Average recoveries varied from 73.2 to 119.6%. Repeatability and intra-laboratory reproducibility conditions of the method expressed as %RSD were less than 20%. These figures were within the SANTE/11312/2021 recovery limits (70-120%) and the values specified for the repeatability (RSD ≤ 20%). The limits of quantification were lower than the maximum residue limits set by the European Union for the potato. No pesticide residues were found at detectable limits in 93 samples. Two samples contained residues below the maximum residue limit (MRL), while nine samples contained residues above the MRLs. Clothianidin and thiamethoxam residues detected in one sample, while acetamiprid were detected in nine samples. The health risk assessment study indicated that potato consumption was safe for consumers.

The degradation of some pesticides (acetamiprid, boscalid, deltamethrin, kresoxim-methyl, pyraclostrobin and pyridaben) by Enterobacter cloacae (plant growth-promoting bacteria) was investigated in vitro. In this study, firstly the effective substances used initially did not have a negative effect on E. cloacae, and the bacteria showed the same growth as the control group in the nutrient agar medium. Secondly, application doses of pesticides were added to erlenmeyer with nutrient broth, and 1 ml of 1×109 cells/ml of E. cloacae solution was inoculated and incubated in a shaker at room temperature (24°C) for 7 days. After the nutrient broth medium was extracted, pesticides were measured by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). When the results were compared with the control group, there was no degradation in acetamiprid, but 98.9% in pyraclostrobin, 98.6% in boscalid, 94.1% in kresoxim-methyl, 73.5% in pyridaben and 57.3% in deltamethrin. It is thought that the results of this study and the information obtained on the degradation of boscalid, deltamethrin, kresoxim-methyl, pyraclostrobin and pyridaben will shed light on future studies.