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.

Determination of fungicide residues in soil using QuEChERS coupled with LC-MS/MS, and environmental risk assessment.

Fungicide residues of soil samples taken from Batak Plain of Çanakkale province of Türkiye were assessed. Fungicide residue analyses were performed with the use of QuEChERS method and LC-MS/MS device. Blank samples were spiked at two different limit of quantification (LOQ) levels for method verification. Overall recovery was identified as 85.69% with an RSD of 12.36% (n=360; SD=10.59). A total of 110 soil samples were taken in November 2020. Present analyses revealed that 59.09% of samples contained fungicide residues at different concentrations. Propiconazole had the highest concentration (1736.06 µg/kg) in one sample, taken from the edge of the field where pesticide wastes were found and 26 fungicides were found at different concentrations in the same sample. Azoxystrobin was encountered in majority of the samples (29 samples). The most frequent fungicides were ordered as; boscalid and tebuconazole (22 samples) > metalaxyl (17 samples) > fluopyram (15 samples). Thirteen triazole fungicides were found in soil samples, mostly at moderately hazardous level (Class II). Risk assessments revealed that hazard levels of fungicides for adults and children were low with a hazard quotient (HQ) and hazard index (HI) of <1. Despite the safe nature of fungicides in soil samples, the greatest HQ values were identified for propiconazole (326.52E-08 for adults and 2449.00E-08 for children). The sum of hazard quotients for all fungicides was 86.31E-08 8 for adult and 647.35E-08 for children. In terms of soil pollution, it is important for farmers to apply fungicides with low HQ levels.

Monitoring and environmental risk assessment of agricultural fungicide and insecticides in water, sediment from Kumkale Plain, Çanakkale-Turkey.

This study was conducted to assess pesticide residues in 34 water and sediment samples taken from Kumkale Plain of Çanakkale-Turkey. Residue analyses were performed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure. For method verification, blank sediment and water samples were spiked at two limits of quantification (LOQ) levels of the pesticides. Overall recovery was 81.66% for sediment and 91.50% for water samples. In sediment samples, chlorpyrifos-M had the highest concentration, pyridaben was encountered in the majority of the samples (15 samples) and the highest number of pesticides (35) was seen in sample no. s13. In water samples, methoxyfenozide had the greatest concentration, metalaxyl was encountered in the highest number of samples (three samples) and the highest number of pesticide (8) was seen in sample no.w13. Sample no. s13 and w13 were taken from around the fountain basin. Pyraclostrobin and chlorantraniliprole residues exceeded the national limits set for water. In terms of hazard quotient (HQ), pesticides in sediment and waters were found to be safe. Despite the safe nature of pesticide on samples, greater attention has been paid on toxicity of the residues. It was concluded that authorities should put strict regulations on agrochemicals to reduce health risks of these chemicals.

Determination of chlorpyrifos-methyl, lambda-cyhalothrin and tebuconazole residues in Sultana seedless grapes sprayed with pesticides under farmer's conditions.

The aim of this study was to investigate pesticide residues on Sultana Seedless Grapes harvested at different times and consequently evaluate the risk. Analyses were performed with the Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure. Pesticide-free grapes were spiked at 3 levels. Chlorpyrifos-methyl, lambda-cyhalothrin and tebuconazole detection limits were 20, 10 and 1 µg kg-1, respectively. These values were below maximum residue levels (MRL) of 1000, 80 and 500 µg kg-1, respectively. The overall recovery of the method was 108.60%. Present values were within acceptable recovery (60-140%) and repeatability (≤20%) ranges set by the Directorate-General for Health and Food Safety (SANTE). The vineyards were sprayed 4 times. Grapes were harvested in the 1st, 3rd, 5th, 7th and 14th days from the last spray. The residues in the samples taken from 5 vine stock groups were determined. MRL-exceeding chlorpyrifos-methyl residue of 1140.09 µg kg-1 was detected in the 1st day. The MRL-exceeding lambda-cyhalothrin (381.15 and 307.39 µg kg-1) and tebuconazole residues (650.58 and 570.85 µg kg-1) were detected in the 1st and 3rd days, respectively. The residues of 7th and 14th day samples were significantly different from the others. Excessive pesticide concentrations did not pose any health risks on consumers.

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.

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

The effects of washing treatments on removal rates of some pesticides residues (acetamiprid, chlorpyrifos and formetanate hydrochloride) on pepper were investigated. Method verification was conducted through spiking pepper samples at 0.1, 1.0 and 10.0 × MRL. QuEChERS method produced average recovery of 104.91% with relative standard deviation (RSD) of 13.41%. LOQ values of acetamiprid, chlorpyrifos and formetanate hydrochloride were estimated as 2, 10 and 5 µg/kg, respectively. Capia peppers grown in open fields were sprayed three times with pesticides. Peppers were harvested after 1st, 2nd and 3rd day of the treatments. Then the peppers were subjected to tap water, acetic acid and citric acid washing and ultrasonic cleaning treatments (for 2 and 5 min). Based on three different harvest times and two different washing durations, processing factors (PFs) and reduction rates were calculated for each washing treatment. The residues gradually decreased during washing treatments with increasing process duration. Similarly, a gradual reduction was noted with the progress of harvest times. This in turn corresponded to an increase in PF. Ultrasonic cleaning and citric acid (9%) washing were more effective than the others. Non-systemic pesticides (chlorpyrifos) were more readily removed than the systemic ones (acetamiprid). Similarly, highly soluble pesticides exhibited higher reduction.

Determination of some pesticide residues in conventional-grown and IPM-grown tomato by using QuEChERS method.

The present study was conducted to determine pesticide (emamectin-benzoate, penconazole and imidacloprid) residues over tomatoes by using QuEChERS method. The method was validated by spiking tomato matrix at 0.1, 1.0, and 10.0 MRL levels of the pesticides. Tomatoes were harvested from two conventional and two Integrated Pest Management-grown fields. Laboratory samples were taken from the bulk samples. Analyses of spiked and real-field tomatoes were performed with QuEChERS procedure. Experimental samples were subjected to LC-MS/MS analysis. As indicated in "CAC/GL 40-1993," representative sample matrix (apple) calibration was used for quantification. The overall recovery was 107.12% with a relative standard deviation of 17.96% (n = 162). Present values were within the specified recovery ranges (60-140%) and repeatability value of (RSD ≤20%) of SANCO. Analysis of field experiment samples showed that both conventional tomato plots had trace levels (less than MRL) of emamectin-benzoate and imidacloprid, whereas there were not any pesticide residues in both IPM tomato plots.

Validation of QuEChERS method for the determination of some pesticide residues in two apple varieties.

This study was undertaken to validate the "quick, easy, cheap, effective, rugged and safe" (QuEChERS) method using Golden Delicious and Starking Delicious apple matrices spiked at 0.1 maximum residue limit (MRL), 1.0 MRL and 10 MRL levels of the four pesticides (chlorpyrifos, dimethoate, indoxacarb and imidacloprid). For the extraction and cleanup, original QuEChERS method was followed, then the samples were subjected to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) for chromatographic analyses. According to t test, matrix effect was not significant for chlorpyrifos in both sample matrices, but it was significant for dimethoate, indoxacarb and imidacloprid in both sample matrices. Thus, matrix-matched calibration (MC) was used to compensate matrix effect and quantifications were carried out by using MC. The overall recovery of the method was 90.15% with a relative standard deviation of 13.27% (n = 330). Estimated method detection limit of analytes blew the MRLs. Some other parameters of the method validation, such as recovery, precision, accuracy and linearity were found to be within the required ranges.

Testing the stability of pesticides during sample processing for the chlorpyrifos and malathion residue analysis in cucumber, including matrix effects.

This article describes the procedure of the testing the stability of compounds during sample processing for the pesticide residue analysis in cucumber, including matrix matched assessment. To find out significant differences, one-tailed t test was applied to the data at 95% confidence level. Our results showed that the calculated value was bigger than the critical value (t ( calc ) > t ( crit )), which means the pesticides were decomposed under our processing conditions.

Biodegradation of trifluralin in Harran soil.

Degradation of trifluralin (alpha, alpha, alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) was investigated in soils taken from three different locations at Harran region of Turkey under laboratory conditions. Surface (0-10 cm) soils, which were taken from a pesticide untreated field Gürgelen, Harran-1 and Ikizce regions in the Harran Plain. were incubated in biometer flasks for 350 days at 25 degrees C. Ring-UL-14C-trifluralin was applied at the rate of 2 microg g(-1) with 78.7 kBq radioactivity per 100 g soil flask. Evolved (14)CO2 was monitored in KOH traps throughout the experiment. Periodically, soil sub-samples were removed and extracted by supercritical fluid extraction (SFE). Unextractable soil-bound 14C residues were determined by combustion. During the 350 days incubation period 6.6, 5.4, and 3.3/' of the applied radiocarbon was evolved as (14)CO2 from the Harran-1, Gürgelen, and Ikizce soil, respectively. At the end of 350 days the SFE-extractable and bound 14C-trifluralin residues were 39.0 and 29.2% of the initially applied herbicide in Gürgelen soil. The corresponding values for Harran-1 and Ikizce soils were 36.2, 28.4% and 41.6, 18.5% respectively.