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With the continuous application of new agricultural chemicals in agricultural systems, it is imperative to study the environmental fate and potential transformation products (TPs) of these chemicals to better assess their ecological and health risks, as well as guide scientific application. The dissipation of fluchloraminopyr was firstly evaluated under aerobic/anaerobic condition in four representative soils, with Dissipation Time 50 (DT50) values ranging from 0.107 to 4.76 days. Eight TPs generated by soil degradation were identified via Ultra-High Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Mass Spectrometry (UHPLC-QTOF/MS) and Density Functional Theory (DFT) calculations. The predominant transformation reactions of fluchloraminopyr in soil include oxidation, dechlorination, hydroxylation, and acetylation. The predictions from toxicological software indicated that the acute and chronic toxicity of TPs to aquatic organisms was significantly lower than that of fluchloraminopyr. Moreover, both M267 and M221 exhibited higher acute oral toxicity to terrestrial organisms compared to the parent compound. Consequently, these findings offer essential ecological risk evaluation data for the judicious application of fluchloraminopyr.

Organophosphorus and organochlorine pesticides, historically or currently widely used in agriculture, are prevalent in the environment and pose significant risks to public health and ecosystems. This study aimed to develop a robust analytical method for quantifying these pesticides in soil and water. By optimizing solid-phase extraction (SPE) and Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) procedures, and utilizing comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOF-MS), we achieved sensitive detection levels of all organophosphorus and organochlorine pesticides at 10 μg/kg for soil and 0.1 μg/kg for water samples. The mean recoveries were in the range of 74.2–118.3 % and 72.3–106.9 % at fortified concentration levels in soil and water, respectively. The method exhibited good linearity (R² ≥ 0.9874) and precision (relative standard deviations from 0.1 % to 29.9 %), providing a reliable approach for environmental monitoring and advancing the capabilities in pesticide residue analysis.

This study evaluated the residue behavior and dissipation dynamics of a new imidacloprid FS 600 seed treatment in potato cultivation systems in Shandong and Jilin, China. Sensitive and accurate UPLC-MS/MS methods were established to quantify imidacloprid residues in potatoes, potato plants, and soil. Results showed that imidacloprid dissipation followed a first-order kinetic model, with half-lives ranging from 6.9 to 26.7 days in plants and 19.8 to 28.9 days in soil. At harvest, the highest average residues in potatoes and soil were 0.778 mg/kg and 0.149 mg/kg, respectively. The dietary risk assessment indicated a chronic risk quotient (CRQ) of 39.73% for adults, indicating minimal risk to human consumers, while the ecological risk quotient (ERQ) and ecotoxicity exposure ratio (TER) revealed low to moderate toxicity to earthworms, warranting caution in the use of this formulation. This research provides valuable data for assessing the safety of imidacloprid FS seed treatment in potato cultivation.

A fast and sensitive analytical method based on UHPLC coupled with tandem mass spectrometry was established to investigate the dissipation and final residual amounts of mefentrifluconazole in rice, and dietary risk to consumers was evaluated. The method provided good linearity (R2 ≥ 0.9979), accuracy (recovery range, 79.0–101.5%), precision (relative standard deviation range, 1.3–13.9%), and sensitivity (limit of quantification, 0.005 mg/kg). The dissipation dynamics of mefentrifluconazole in rice followed first-order kinetics, with half-lives of 2.8–16.6 days. The final residues of mefentrifluconazole in various samples of harvested brown rice ranged from less than the limit of quantification to 0.092 mg/kg, the latter value being higher than the maximum residue limit recommended by the European Union. Comparative dietary exposure of mefentrifluconazole was assessed using field data and Chinese dietary patterns for different genders, regions, and age data. Although the results showed acceptable levels of risk for both acute exposure (the percentage of the acute reference dose ≤ 0.7483%) and chronic dietary intake (the percentage of acceptable daily intake ≤ 31.8516%), more studies of children are needed because they are at higher risk than other groups. This work provides the necessary data for registering and establishing the maximum residue limit for mefentrifluconazole in rice in China and reveals the potential risks to different groups of long-term application of mefentrifluconazole to rice and other crops.

As new agrochemicals are continuously introduced into agricultural systems, it is essential to investigate their uptake and metabolism by plants to better evaluate their fate and accumulation in crops and the subsequent risks to human exposure. In this study, the uptake and elimination kinetics and transformation of a novel insecticide, cyetpyrafen, in two model crops (lettuce and rice) were first evaluated by hydroponic experiments. Cyetpyrafen was rapidly taken up by plant roots and reached a steady state within 24 h, and it was preferentially accumulated in root parts with root concentration factors up to 2670 mL/g. An uptake mechanism study suggested that root uptake of cyetpyrafen was likely to be dominated by passive diffusion and was difficult to transport via xylem and phloem. Ten phase I and three phase II metabolites of cyetpyrafen were tentatively identified in the hydroponic-plant system through a nontarget screening strategy. The structures of two main metabolites (M-309 and M-391) were confirmed by synthesized standards. The metabolic pathways were proposed including hydroxylation, hydrolysis, dehydrogenation, dehydration and conjugation, which were assumed to be regulated by cytochrome P450, carboxylesterase, glycosyltransferase, glutathione S-transferases and peroxidase. Cyetpyrafen and its main metabolites (M-409, M-309 and M-391) were estimated to be harmful/toxic toward nontarget organisms by theoretical calculation. The high bioaccumulation and extensive transformation of cyetpyrafen highlighted the necessity for systematically assessing the crop uptake and metabolism of new agrochemicals.

A 3-month experiment was designed to research the impact of trifluralin (TFL) on soil microbial communities and functions under the condition of greenhouse. In this work, silty loam from Langfang was treated with three doses of TFL (1,260, 12,600, and 126,000 g ha−1) and incubated for 90 days. The half-lives of TFL were 15–23 days in all cases. The bacterial and fungal diversities and community structures were impacted by TFL. The bacterial functions of chemoheterotrophy and sulfur oxidation were decreased shortly, but the hydrocarbon degradation ability was significantly increased in the results of functional annotation of prokaryotic taxa (FAPROTAX). For the predicted results of Tax4Fun, amino acid (arginine and proline) metabolism and ABC transporter were decreased significantly, while nitrogen metabolism and ribosome translation were significantly increased. In conclusion, this work aids us to understand the risk of TFL in soil more comprehensively.

The analysis of pesticide residues in aquatic products is challenging due to low residue levels and the complex matrix interference. In this study, we developed a simple, fast method for the trace analysis of 90 pesticides and metabolites in aquatic products. The analytes covered a wide polarity range with log Kow (log octanol-water partition coefficient) ranging from −1.2 to 6.37. Grass carp (Ctenopharyngodon idellus) and prawn (Penaeus chinensis) samples were chosen to validate the quantification method. The samples were extracted by 0.2% formic-acetonitrile, cleaned by solid-phase extraction (PRiME HLB), and analyzed by high performance liquid chromatography−tandem mass spectrometry. The results showed good linearities for the analytes and were observed in the range of 0.05–50 μg/L. The recoveries of the method were within 50.4–118.6%, with the relative standard deviations being lower than 20%. The limits of quantifications (LOQs) of the method were in the range of 0.05–5.0 μg/kg, which were superior to values compared with other research. The developed method was applied to detect pesticide residues in prawn samples from eastern coastal areas of China. Three herbicide residues of diuron, prometryn, and atrazine were detected in prawn samples. The method was sensitive and efficient, which is of significance in expanding the screening scope and improving the quantitative analysis efficiency in aquatic products.

Given the key role of bees as indicators for environmental assessment, residues in bees and bee products have attracted great interest. In this regard, an improved, highly sensitive method for quantifying the insecticide pyriproxyfen and its four metabolites (4′-OH-Pyr, DPH-Pyr, 2-OH-PY, 4′-OH-POP) in honeybees, larvae, and bee products (honey, pollen, royal jelly and wax) should be established. For this purpose, we used ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry for rapid quantification (≤5 min). Recoveries for various matrices ranged from 73.77% to 114.97%, with satisfactory intra-day and inter-day precision (relative standard deviations of 0.03–8.61% and 0.10–7.25%, respectively). The results demonstrated excellent linearity (R2 > 0.9903) with a limit of quantification of 1 μg/kg for six different matrices. We collected and analyzed 597 samples (honey, bees and wax) from four major beekeeping areas in China. Only 47 of these samples contained residues of pyriproxyfen and two of its metabolites (2-OH-PY, 4′-OH-Pyr), and high levels of contamination were found in bee samples (2–739 μg/kg), with substantive accumulation in wax (levels were 9.49% higher than in other samples). The result demonstrate that the method provides a reliable and convenient means of monitoring pyriproxyfen and its metabolites in bee products for better product quality, human health, and international commercial competition and also lays a foundation for risk assessment of potential pyriproxyfen contamination in China.

In 2018, we conducted a cross-sectional study to investigate azole resistance in environmental Aspergillus fumigatus isolates obtained from different agricultural fields in China. Using 63 soil cores, we cultured for azole-resistant A. fumigatus and characterized isolates by their cyp51A gene type, short tandem repeat genotype, and mating type. Of 206 A. fumigatus isolates, 21 (10.2%) were azole resistant. Nineteen of 21 had mutations in their cyp51A gene (5 TR34/L98H, 8 TR34/L98H/S297T/F495I, 6 TR46/Y121F/T289A). Eighteen were cultured from soil samples acquired from strawberry fields, suggesting this soil type is a potential hotspot for azole resistance selection. Twenty resistant isolates were mating type MAT1-1, suggesting asexual sporulation contributed to their evolution. Prochloraz, difenoconazole, and tebuconazole were the most frequently detected fungicides in soil samples with azole-resistant fungus. Our study results suggest that managing the fungicides used in agriculture will help contain the problem of antifungal drug resistance in clinics.

Neonicotinoid pesticide residues are ubiquitous in various foodstuffs and may adversely affect human health. We performed a nationwide survey of neonicotinoid residues in foodstuffs collected from Chinese markets and evaluated the risks of chronic and acute exposure in 1–6-year-old children and the general population. Among the 3406 samples of 13 commodities, 62.21% contained neonicotinoids with concentrations ranging from 0.1 to 1471.43 μg/kg, and 37.58% were simultaneously contaminated with 2–7 neonicotinoids. Acetamiprid, thiamethoxam, and imidacloprid were the top three detected neonicotinoids (22.14–34.32% of samples). Chronic and acute cumulative risk assessment using the relative potency factor method revealed that exposure to neonicotinoids was within established safety limits (below 1); however, the acute risk was much greater than the chronic risk (chronic hazard index range, 1.40 × 10−6–2.33 × 10−3; acute hazard index range, 1.75 × 10−6–0.15). A relatively greater acute cumulative risk was found for children with respect to consumption of grapes, mandarins, and cowpeas (acute hazard index range, 0.11–0.15). Despite the low health risk, the potential health hazards of neonicotinoids should be continuously assessed, given their ubiquity and cumulative effects.

Abstract In this study, the residues of beta-cypermethrin, pyriproxyfen, avermectin, diflubenzuron and chlorothalonil in button mushrooms were investigated. The dietary risks of ingesting button mushrooms that have had these pesticides applied by two different methods under normal plant conditions were evaluated. The dissipation of these pesticides into the soil was also studied. According to the maximum residue limits (MRLs) and acceptable daily intakes (ADIs), the final residues of beta-cypermethrin, pyriproxyfen, avermectin, diflubenzuron, and chlorothalonil were safe for human consumption after these pesticides were applied by spraying 2 times at the dosages of 900, 750, 540, 562.5, and 540 g a.i.ha−1. The dissipation experiment results demonstrated that these pesticides dissipated rapidly after spraying, and there were no residues that could be detected at harvest time when the pesticides were mixed with substrates. According to this work, the application methods of spraying and incorporation with these pesticides at 1 and 1.5 times of the recommended dosage are safe and proper in cultivating button mushrooms.

Imidacloprid (IMI) is a typical neonicotinoid with the largest usage in agricultural orchards in China. The long-term repeated use and the lack of proper protective measures may result in rural farmers and people living near orchards to be inevitably exposed to IMI. Excessive exposure may cause potential adverse effects on human health. To explore the characteristics of human exposure to IMI in urine, different groups of people, including pesticide applicators and their family members, and kindergarten children near IMI-applied orchards were investigated. The IMI and metabolite, 6-chloronicotinic acid (6-CNA), concentrations in urine were creatinine-adjusted to compensate for a possible dilution effect. Target analytes were detected in 100% of 1926 urine samples. The results showed that the IMI concentration in the 1-d urine from the rural residents significantly increased after a spraying event (p 0.05). Females had higher exposure concentrations than that of males. People from different villages demonstrated diverse exposure levels with Geomean differences of 1.13–3.28 fold. For 3–6 years-old children, urinary concentrations from the rural group (Geomean: 3.73 μg/g creatinine for IMI; 3.95 μg/g creatinine for 6-CNA) were significantly higher than that of the urban group (Geomean: 1.13 μg/g creatinine for IMI; 0.88 μg/g creatinine for 6-CNA) (p = 0.00001), and the younger children tended to have higher exposure risk. Our findings showed that people in the Henan orchard areas were likely exposed to IMI to varying degrees. Further research on the health risk evaluation of IMI and controlling the exposure risks is needed. Keywords: Neonicotinoids, Imidacloprid, Metabolite, 6-Chloronicotinic acid, Urine, Human exposure

In last decade, there has been a concerted effort to reduce the potential threats of honeybees' population due to exposure to neonicotinoid pesticides. A new perspective was put forward to reduce the potential ecological toxicity of neonicotinoid dinotefuran to honeybee in terms of an enantiomeric level in the study. Toxicity of dinotefuran was enantioselective, and S-dinotefuran was 41.1- to 128.4-fold more toxic than R-dinotefuran to honeybee Apis mellifera (Apis mellifera Linnaeus), whereas R-dinotefuran exhibited comparative insecticidal activities (1.7–2.4 times) to typical sucking pests Aphis gossypii and Apolygus lucorum compared to racemic mixtures. Our data suggested that use of R-dinotefuran could have a good efficacy in controlling target pests while minimizing hazard to honeybees. The mechanism for chiral specific toxicity to honeybee was further characterized by electrophysiological studies and molecular docking. S-dinotefuran appears to be more toxic by binding to α8 subunit of nAChR of Apis mellifera. The α8 also have a more stable, functional binding cavity to S-dinotefuran with a higher binding score of 7.15, primarily due to an extensive hydrogen bond network. Therefore, new chiral products with a high proportion of or an enantiomeric pure R-dinotefuran are recommended to achieve effective pests control reducing hazard to honeybee populations. Keywords: Chiral neonicotinoid, Toxicity reduction, Dinotefuran enantiomers, Enantioselective toxicology, Honeybee

A simple residue analytical method based on the QuEChERS approach and high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection was developed for the analysis of fipronil and its three metabolites in cottonseed, cotton plant and soil. The average recoveries of four test compounds from all three matrices were 78.6-108.9% at the level of 0.005 to 0.5 mg/kg, with an RSD in the range of 0.6 to 13.7%. The limit of quantification (LOQ) of the four test compounds ranged from 0.005 to 0.01 mg/kg. The results of the residual dynamics experiments showed that fipronil dissipated rapidly in cotton plants and soil and that oxidation and photolysis were the main degradation pathways. Moreover, the bi-exponential models demonstrated a good fit of the measured data for fipronil in cotton plants and soil, with R2 in the range of 0.8989 to 0.9989. Furthermore, a total of 40 samples of cottonseed from Shandong Province were analyzed, and all of the samples were free from the four test compound residues.

Exhaustive hydro-distillation of Descurainia sophia (L.) Webb ex Prantl (flixweed) collected from two different locations (Cangzhou city-Sample 1 and Beijing city-Sample 2) gave in both cases yellowish colored oils in 0.31 and 0.26% yield, respectively. Detailed chemical composition of the essential oils was analyzed by GC and GC/MS, and forty and thirty-eight compounds were identified. The results indicated that the most abundant component of Sample 1were cis-β-ocimene (20.1%), menthol (11.27%), neoisomenthyl acetate (3.5%), alloaromadendrene (2.28%) and longicyclene (2.25%). Compared with the constituents of Sample 1, several chemical compounds such as 1,8-cineole, α-eudesmol, cis, trans-farnesol and β-pinene were not detected in Sample 2 although it was similarly dominated by cis-β-ocimene (17.12%), menthol (10.7%) and neoisomenthyl acetate (2.96%). Final analysis of the chemical constituents in the essential oils of the two samples showed similarity in their chemical composition, but the relative content of all shared chemical constituents in Sample 2 was lower than that in Sample 1.