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Abstract Agricultural environment is often contaminated with various chemicals (e.g., pesticides, heavy metals) and microplastics due to the uses of plastic products. The effects of chemical contaminants or microplastics on terrestrial environment have been extensively studied, but the studies on the co-presence of chemical contaminants and microplastics are relatively limited. This study was set to investigate the effect of co-presence of microplastics (i.e., low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastic films) and chemical contaminants (i.e., cadmium (Cd) and procymidone (PCM)) in soil on the lettuce growth and Cd and PCM uptake by lettuce using pot tests. The lettuce leaf lengths were not affected by the presence of only Cd or PCM, but the rates of change in the lettuce leaf number were adversely affected by the presence of PCM. The presence of only LDPE or PVC in soil at the concentrations used in this study did not have significant impacts on the lettuce growth. But the co-presence of Cd and LDPE and the co-presence of PCM and PVC resulted in the negligible increases in the lettuce leaf length and leaf number with time, although the lettuce growths were statistically similar in the Cd- or PCM-contaminated soils regardless of the presence of microplastics. The results suggest that the adverse effects of Cd or PCM can be intensified by the co-presence of microplastics, and the effects can be different depending on the types of microplastics. The promoted adverse effects of chemical contaminants in the co-presence of microplastics can be supported by the tendency of the increased absorption of Cd or PCM by lettuce in the co-presence of microplastics. Overall, this study shows the need for management of both chemical contaminants and microplastics that may reside in the agricultural environment.

ObjectiveThis study aimed to prepare proficiency testing samples that are closer to the actual samples and have good homogeneity and stability， and the ability of national laboratories to detect procymidone， carbofuran， and parathion in vegetables was analyzed through proficiency testing.MethodsThe proficiency testing samples were prepared by adding the target standard solution to the vegetable juice that was sold in the market， and the uniformity and stability were tested. The assigned value and standard deviation of proficiency testing were obtained by robust statistics， and the z value was applied to evaluate the results submitted by the participating laboratories.ResultsThe prepared samples were tested for homogeneity and stability， and met the proficiency testing requirements. The samples were applied to proficiency testing， and 94 laboratories participated nationwide， of which the laboratory satisfaction rate in the procymidone project was 84.5%； the laboratory satisfaction rate in the carbofuran project was 83.3%； the laboratory satisfaction rate in the parathion project was 89.6%.ConclusionThe sample prepared by the preparation method in this study has favorable homogeneity and stability and can meet the requirements of the sample for proficiency testing. The statistical results of proficiency testing showed that the detection ability of procymidone， carbofuran， and parathion in vegetables used in participating laboratories was generally favorable. Through this capability verification activity， we gained an understanding of the testing level of laboratories in this field and achieved the expected results.

To explore the feasibility of applying nanobodies in colloidal gold immunochromatography assay (GICA) for small-molecule harmful substances, this study systematically investigated the effects of colloidal gold labeling parameters, colloidal gold working buffer and sample pretreatment methods on GICA using the pesticide procymidone as a model. The results showed that the size of colloidal gold particles, labeling pH and the amount of antibody used were the key factors to ensure the stability of the nanobody-gold-labeled probes. Under the optimal conditions, the limit of detection, half-maximal inhibitory concentration (IC50) and visual detection limit of GICA for procymidone were 0.44, 6.29 and 200 μg/L, respectively. The sensitivity was 5.1-fold higher than that of conventional monoclonal antibody-based GICA. The quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure was used for the pretreatment of Chinese leek, cucumber and tomato samples. Based on the excellent organic solvent tolerance of nanobodies, the organic solvent blow-drying procedure was omitted. The average recoveries of the spiked samples ranged from 80.1% to 109.6%, and the results for the actual samples were consistent with those of gas chromatography-mass spectrometry (GC-MS). This study showed that nanobodies are a potential alternative to conventional antibodies for immunoassays for the rapid detection of small molecules. The proposed nanobody-based GICA can be used for the rapid screening of procymidone in vegetables with the advantages of high sensitivity, high accuracy, rapidity and simplicity.

Objective: This study aimed to help with the scientific management of leek food safety in Hunan Province. Methods: 24 kinds of pesticides and 5 kinds of heavy metals in 690 leek samples from Hunan Province were detected. Results: ① Pesticide residues were detected in 23.19% of the 690 samples, and the top three pesticides were determined to be carbendazim, procymidone and cypermethrin. The exceeding rate of pesticide residues was 5.80%, and the highest exceeding rate was 2.61% of procymidone. ② The detection rate of heavy metal elements was 77.68%, and the exceeding rate was 3.62%. The highest detection rate and exceeding rate of heavy metal elements was Cd. Conclusion: High pesticide residues in leek were confirmed, and the detection rate of heavy metal elements in leeks is much higher than that of pesticide residues. Among them, pesticide procymidone and heavy metal Cd are the main over-standard items of leeks. It is suggested to strengthen the continuous monitoring of pesticide residues and heavy metal pollution in leeks.

ObjectiveTo prepare pesticide residues in fruit matrix samples that meet the requirements of homogeneity and stability for the proficiency test.MethodsThe pollution-free apple was selected as the main raw material to prepare the pesticide residue proficiency test samples of myclobutanil and procymidone， and to evaluate the homogeneity and stability. The results of the proficiency test were assessed using robust analysis and Ζ value.ResultsThe homogeneity and stability of the reference materials met the relevant requirements. Among 109 laboratories participated in the proficiency testing， 107 （98.2%） laboratories had satisfactory results. Suspicious test results were reported only in two laboratories， one laboratory for each of the two assessment items.ConclusionAn apple powder matrix sample with pesticide residues is successfully prepared for proficiency test， and could provide an evaluation tool for pesticide residue testing laboratories.

BackgroundProcymidone (PCM) exposure can cause damage to reproductive organs of male mice, but whether its mechanism is related to the retinoic acid (RA) signaling pathway is unclear.ObjectiveTo explore the possible mechanism of PCM-induced testes damage in adolescent mice.MethodsThree-week-old ICR mice (n=64) were randomly divided into a control group and three dose groups (low, medium, and high), with 16 mice in each group. PCM was administered orally at 0, 50, 100, and 200 mg·kg−1·d−1 for 21 consecutive days. Serum and bilateral testes in each mouse were collected to detect content of testosterone in serum and to observe histological changes in testis section after the mice were sacrificed one week after cessation of drug administration. Real-time fluorescence quantitative PCR and Western blotting were used to detect the mRNA expression abundances of genes related to the RA signaling pathway and apoptosis genes Casp9 and Casp12, and the protein expression levels of CYP26A1, ALDH2, and CASP9 respectively.ResultsCompared with the control group, there was no significant change in the overall appearance and testicular appearance of mice in each dose group after the PCM exposure. According to pathological section observation, the testicular seminiferous tubules of mice in the low-dose group showed slight atrophy and reduced sperm production; the testes of mice in the medium- and the high-dose groups showed obvious pathological damage (e.g. dilated lumen of seminiferous tubules, damaged spermatogenic epithelium, decreased number of spermatogonia, and partial absence of sertoli cells); as the concentration of PCM increased, the degree of spermatogenic epithelial damage in mice gradually increased and the number of spermatozoa in the seminiferous tubules decreased. There were no significant differences in the distance between the anus and the genitals, testicular mass, testicular volume, and testicular organ coefficient among the four groups of mice (P>0.05). The body weights of the mice in the low-, medium-, and high-dose groups were (34.91±1.89), (34.88±1.75), and (32.94±1.37) g respectively, and that in the high-dose group was lower than that in the control group, (35.93±1.99) g, (P

This study synthesized the NaGdF4@NaGdF4: Yb, Tm@NaGdF4: Yb, Nd upconversion nanoparticles (UCNPs), combined with another three-layer structure NaYF4@NaYF4: Yb, Er@NaYF4 UCNPs, with a core-shell-shell structure, effectively suppressing fluorescence quenching and significantly improving upconversion luminescence efficiency. Two types of modified UCNPs were coupled with antibodies against fenpropathrin and procymidone to form signal probes, and magnetic nanoparticles were coupled with antigens of fenpropathrin and procymidone to form capture probes. A rapid and sensitive fluorescence immunoassay for the simultaneous detection of fenpropathrin and procymidone was established based on the principle of specific binding of antigen and antibody and magnetic separation technology. Under the optimal competitive reaction conditions, different concentrations of fenpropathrin and procymidone standards were added to collect the capture probe-signal probe complex. The fluorescence values at 542 nm and 802 nm were measured using 980 nm excitation luminescence. The results showed that the detection limits of fenpropathrin and procymidone were 0.114 µg/kg and 0.082 µg/kg, respectively, with sensitivities of 8.15 µg/kg and 7.98 µg/kg, and they were applied to the detection of fenpropathrin and procymidone in tomatoes, cucumbers, and cabbage. The average recovery rates were 86.5~100.2% and 85.61~102.43%, respectively, with coefficients of variation less than 10%. The results showed good consistency with the detection results of high-performance liquid chromatography, proving that this method has good accuracy and is suitable for the rapid detection of fenpropathrin and procymidone in food.

Procymidone (PCM) is a fungicide commonly used to prevent and control plant diseases, and it is also an environmental endocrine disruptor that has a typical anti-androgen effect on the function and/or structure of the vertebrate reproductive system. The activation of the unfolded protein response (UPR) will fold the protein correctly to ensure the cell’s survival. PCM regulates GRP78 by affecting the level of hormones, and there is a regulatory relationship between the UPR, the circRNAs and the miRNAs. In vivo experiments, PCM (suspended in soybean oil) was orally administered to adolescent female mice for 21 days in 3 different doses of 50 mg kg–1 day–1 (low dose), 100 mg kg–1 day–1 (medium dose) and 200 mg kg–1 day–1 (high dose) to cause ovaries and uteruses damage, and in vitro experiments, various doses of PCM from 0.33 × 10−5 (low dose) to 1 × 10−5 (medium dose) then 3 × 10−5 M (high dose) were used to induce injury on the ovaries and uteri of the mice. We found out that both in vivo and in vitro, PCM caused dose-dependent damages to the ovaries and uteri, increased their circRNA Scar levels and decreased circZc3h4 abundance. Also, all UPR signaling pathways in the low-dose group and some in the middle-dose group were activated. It is speculated that UPR may antagonize the partial ovarian and uterine damage in adolescent mice induced by PCM at doses less than NOAEL via changes in circZc3h4 and circRNA Scar.

Procymidone is used as a preventive and curative fungicide to control fungal growth on edible crops and ornamental plants. It is one of the most frequently used pesticides and has a high detection rate, but its residue behaviors remain unclear in green onion and garlic plants (including garlic, garlic chive, and serpent garlic). In this study, the dissipation and terminal residues of procymidone in four matrices were investigated, along with the validation of the method and risk assessment. The analytical method for the target compound was developed using gas chromatography-tandem mass spectrometry (GC-MS/MS), which was preceded by a Florisil cleanup. The linearities of this proposed method for investigating procymidone in green onion, garlic, garlic chive, and serpent garlic were satisfied in the range from 0.010 to 2.5 mg/L with R2 > 0.9985. At the same time, the limits of quantification in the four matrices were 0.020 mg/kg, and the fortified recoveries of procymidone ranged from 86% to 104%, with relative standard deviations of 0.92% to 13%. The dissipation of procymidone in green onion and garlic chive followed first-order kinetics, while the half-lives were less than 8.35 days and 5.73 days, respectively. The terminal residue levels in garlic chive were much higher than those in green onion and serpent garlic because of morphological characteristics. The risk quotients of different Chinese consumer groups to procymidone in green onion, garlic chive, and serpent garlic were in the range from 5.79% to 25.07%, which is comparably acceptable. These data could provide valuable information on safe and reasonable use of procymidone in its increasing applications.

The purpose of this study was to analyze the impact of procymidone application in periurban horticultural greenhouses, especially on workers (applicators and assistants) and soil and plastic mulching, when mechanically pressurized application systems were employed. The mean Potential Dermal Exposure (PDE) was measured using the Whole Body Dosimetry technique. The PDE for the applicators was 188 mL h−1 ± 103 mL h−1, and 14.7 mL h−1 ± 6.3 mL h−1 for the assistants. In the first case, the most exposed body sections were the upper right and left (46.8 mL h−1 ± 23.4 mL h−1; 47.0 mL h−1 ± 23.5 mL h−1) and lower (20.8 mL h−1 ± 10.4 mL h−1; 17.3 mL h−1 ± 8.7 mL h−1) legs, while in the case of assistants, hands and legs were the most impacted limbs. Regarding the Margin of Safety (MOS) during the mix and load stage, two of three pesticide preparations resulted unsafe, while for the applicators, six of six spraying operations were unsafe. For the assistants, five of five operations were safe, but three of them were close to the safety limit.Procymidone distribution between drift (0.03% ± 0.07 %), applicator (0.20% ± 0.15 %), polyethylene mulching (8.5% ± 4.5 %) and soil (3.0% ± 1.1 %) was determined with respect to the total pesticide applied. Procymidone soil impact was also evaluated using Eisenia andrei behavioral tests, finding positive correlations between procymidone application and avoidance and reproduction tests.

Leafy vegetables are widely consumed in South Korea, especially in the form of kimchi and namul (seasoned vegetables) and are used for wrapping meat. Therefore, the management of pesticide residues in leafy vegetables is very important. A total of 17,977 samples (49 leafy vegetables) were mainly collected in the largest production area of leafy vegetables (Gwangju Metropolitan City and Chonnam Province) in South Korea. They were analyzed within the government’s monitoring programs (Gwangju Metropolitan City) of pesticide residues between 2005 and 2019. Pesticide residues were found in 2815 samples (15.7%), and 426 samples (2.4%) from among these exceeded the specified maximum residue limits (MRLs). Samples exceeding the MRLs were mostly detected in spinach, ssamchoo (brassica lee ssp. namai), crown daisy, lettuce, and perilla leaves. Azoxystrobin, dimethomorph, and procymidone were the most frequently detected pesticides. However, procymidone, diniconazole, and lufenuron were found to most frequently exceed the MRLs. The rate of MRLs exceeding has been managed below the average (2.4%) more recently than in the past in this area. Further, leafy vegetables with the most violations of the MRLs in our study in South Korea were not harmful to health by a risk assessment (the range of the hazard index was 0.001–7.6%).

Qualitative electrochemical characterization of procymidone (PRO) and tebuthiuron (TBH) was carried out by cyclic voltammetry using a carbon paste electrode. The studies suggest that analyte mass transfer is controlled by diffusion, and that oxidation of PRO and TBH occurs by means of irreversible electronic transfer of one electron. Oxidation of PRO and TBH occurs close to +0.820 V and +1.075 V (vs. Ag|AgCl, KCl 3.0 mol L-1), respectively, in a 0.1-M KOH solution as supporting electrolyte. Quantitative analyses were carried out by differential-pulse voltammetry, a technique which is more sensitive and selective. Detection and quantification limits were determined for PRO and TBH in the absence of matrix, in a potable-water matrix, and in a nonpotable-water matrix, for which the ranges of reproducibility, intermediate precision and recovery rates were (1.01 and 4.20 %), (4.08 and 9.56 %), and (90.6 and 115 %) for PRO, and (1.59 and 3.92 %), (4.84 and 7.46 %), and (91.3 and 119 %), for TBH, respectively. The results indicate that the new method is selective, simple and cheap to simultaneously quantify PRO and TBH in water samples.

Procymidone was chosen as the model compound and its phototransformation was followed under sunlight irradiation. The main photodegradation products on silica is 3,5-dichloroaniline and 3,5-diclorphenilisocyanate. The use of ammonium ferric citrate enhances the degradation of the procymidone.