Carbendazim residues in vegetables in China between 2014 and 2016 and a chronic carbendazim exposure risk assessment

Food supply toxicants and additives alter the gut microbiota and risk of metabolic disease

Metabolic disease is rising along with both global industrialization and the use of new commercial, agricultural, and industrial chemicals and food additives. Exposure to these compounds may contribute to aspects of metabolic diseases such as obesity, diabetes, and fatty liver disease. Ingesting compounds in the food supply is a key route of human exposure, resulting in the interaction between toxicants or additives and the intestinal microbiota. Toxicants can influence the composition and function of the gut microbiota, and these microbes can metabolize and transform toxicants and food additives. Microbe-toxicant interactions in the intestine can alter host mucosal barrier function, immunity, and metabolism, which may contribute to the risk or severity of metabolic disease development. Targeting the connection between toxicants, food, and immunity in the gut using strategies such as fermentable fiber (i.e., inulin) may mitigate some of the effects of these compounds on host metabolism. Understanding causative factors in the microbe-host relationship that promote toxicant-induced dysmetabolism is an important goal. This review highlights the role of common toxicants (i.e., persistent organic pollutants, pesticides, and fungicides) and food additives (emulsifiers and artificial sweeteners) found in our food supply that alter the gut microbiota and promote metabolic disease development.

Quality and Safety in Asparagus Cultivation: A Three-Year Case Study Comparing Standardized Agricultural Bases and Small-Scale Farmers

To investigate the quality and safety difference between agricultural standardization bases and small-scale farmers, we carried out a three-year investigation of asparagus from seven production sites of different sizes in Pinghu city, Zhejiang Province, China, from 2021 to 2023. We documented trace elements (Fe, Zn, Mn, and Cu), quality indicators (vitamin B1, vitamin B2, vitamin C, total sugar, and proteins), and pesticide residues. The evaluation indicated that the quality of asparagus in standardization bases 1-4 was higher than that in small farmer sites 5-7. The detection rate of pesticides in asparagus was 23.81% (15/63), with a low concentration range of 0.001-0.130 mg mL-1. Low pesticide levels reflect Pinghu's effective green pest control measures. Results showed that the quality and safety of asparagus at the standardization bases are superior to those at small-scale farmer sites, and our findings may inform better management practices for both large-scale and small-scale asparagus farmers.

Microbial degradation of the benzimidazole fungicide carbendazim by Bacillus velezensis HY-3479

Carbendazim (methyl benzimidazol-2-ylcarbamate: MBC) is a fungicide of the benzimidazole group that is widely used in the cultivation of pepper, ginseng, and many other crops. To remove the remnant carbendazim, many rhizobacteria are used as biodegradation agents. A bacterial strain of soil-isolated Bacillus velezensis HY-3479 was found to be capable of degrading MBC in M9 minimal medium supplemented with 250 mg/L carbendazim. The strain had a significantly higher degradation efficiency compared to the control strain Bacillus subtilis KACC 15590 in high-performance liquid chromatography (HPLC) analysis, and HY-3479 had the best degradation efficiency of 76.99% at 48 h. In gene expression analysis, upregulation of carbendazim-degrading genes (mheI, hdx) was observed in the strain. HY-3479 was able to use MBC as the sole source of carbon and nitrogen, but the addition of 12.5 mM NH4NO3 significantly increased the degradation efficiency. HPLC analysis showed that the degradation efficiency increased to 87.19% when NH4NO3 was added. Relative gene expression of mheI and hdx also increased for samples with NH4NO3 supplementation. The enzyme activity of the carbendazim-degrading enzyme and the 2-aminobenzimidazole-degrading enzyme was found to be highly present in the HY-3479 strain. It is the first reported B. velezensis strain to biodegrade carbendazim (MBC). The biodegradation activity of strain HY-3479 may be developed as a useful means for bioremediation and used as a potential microbial agent in sustainable agriculture.

Transcriptomic profile in carbendazim-induced developmental defects in zebrafish (Danio rerio) embryos/larvae

Carbendazim is a widely used fungicide to protect agricultural and horticultural crops against a wide array of fungal species. Published reports have shown that the wide usage of carbendazim resulted in reprotoxicity, carcinogenicity, immunotoxicity, and developmental toxicity in mammalian models. However, studies related to the developmental toxicity of carbendazim in aquatic organisms are not clear. To address this gap, an attempt was made by exposing zebrafish embryos to carbendazim (800 μg/L) and assessing the phenotypic and transcriptomic profile at different developmental stages [24 hour post fertilization (hpf), 48 hpf, 72 hpf and 96 hpf). At 48 hpf, phenotypic abnormalities such as delay in hatching rate, deformed spinal axial curvature, and pericardial edema were observed in zebrafish larvae over its respective controls. At 72 hpf, exposure of zebrafish embryos exposed to carbendazim resulted in scoliosis; however, unexposed larvae did not exhibit signs of scoliosis. Interestingly, the transcriptomic analysis revealed a total of 1253 DEGs were observed at selected time points, while unique genes at 24 hpf, 48 hpf, 72 hpf and 96 hpf was found to be 76.54 %, 61.14 %, 92.98 %, and 68.28 %, respectively. Functional profiling of downregulated genes revealed altered transcriptomic markers associated with phototransduction (24 hpf and 72 hpf), immune system (48 hpf), and SNARE interactions in the vesicular pathway (96 hpf). Whereas functional profiling of upregulated genes revealed altered transcriptomic markers associated with riboflavin metabolism (24 hpf), basal transcription factors (48 hpf), insulin signaling pathway (72 hpf), and primary bile acid biosynthesis (96 hpf). Taken together, carbendazim-induced developmental toxicity could be ascribed to pleiotropic responses at the molecular level, which in turn might reflect phenotypic abnormalities.

Residue levels, processing factors and risk assessment of pesticides in ginger from market to table

Ginger is consumed as a spice and medicine globally. However, pesticide residues in ginger and their residue changes during processing remain poorly understood. Our results demonstrate that clothianidin, carbendazim and imidacloprid were the top detected pesticides in 152 ginger samples with detection rates of 17.11-27.63%, and these pesticides had higher average residues of 44.07-97.63 μg/kg. Although most samples contained low levels of pesticides, 66.45% of the samples were detected with pesticides, and 38.82% were contaminated with 2-5 pesticides. Peeling, washing, boiling and pickling removed different amounts of pesticides from ginger (processing factor range: 0.06-1.56, most <1). By contrast, pesticide residues were concentrated by stir-frying and drying (0.50-6.45, most >1). Pesticide residues were influenced by pesticide physico-chemical parameters involving molecular weight, melting point, degradation point and octanol-water partition coefficient by different ginger processing methods. Chronic and acute dietary risk assessments suggest that dietary exposure to pesticides from ginger consumption was within acceptable levels for the general population. This study sheds light on pesticide residues in ginger from market to processing and is of theoretical and practical value for ensuring ginger quality and safety.

Potato glycoside alkaloids exhibit antifungal activity by regulating the tricarboxylic acid cycle pathway of Fusarium solani

Fusarium solani is a pathogenic fungus that causes significant harm, leading to crop yield reduction, fruit quality reduction, postharvest decay, and other diseases. This study used potato glycoside alkaloids (PGA) as inhibitors to investigate their effects on the mitochondrial structure and tricarboxylic acid (TCA) cycle pathway of F. solani. The results showed that PGA could inhibit the colony growth of F. solani (54.49%), resulting in the disappearance of the mitochondrial membrane and the loss of contents. PGA significantly decreased the activities of aconitase (ACO), isocitrate dehydrogenase (IDH), α-ketoglutarate dehydrogenase (α-KGDH), succinate dehydrogenase (SDH), fumarase (FH), malate dehydrogenase (MDH), succinyl-CoA synthetase (SCS), and increased the activity of citrate synthase (CS) in F. solani. After PGA treatment, the contents of acetyl coenzyme A (CoA), citric acid (CA), malic acid (L-MA), and α-ketoglutaric acid (α-KG) in F. solani were significantly decreased. The contents of isocitric acid (ICA), succinyl coenzyme A (S-CoA), succinic acid (SA), fumaric acid (FA), and oxaloacetic acid (OA) were significantly increased. Transcriptomic analysis showed that PGA could significantly affect the expression levels of 19 genes related to TCA cycle in F. solani. RT-qPCR results showed that the expression levels of ACO, IDH, α-KGDH, and MDH-related genes were significantly down-regulated, and the expression levels of SDH and FH-related genes were significantly up-regulated, which was consistent with the results of transcriptomics. In summary, PGA can achieve antifungal effects by reducing the tricarboxylic acid cycle's flow and regulating key genes' expression levels. This study reveals the antifungal mechanism of PGA from the perspective of TCA cycle, and provides a theoretical basis for the development and application of PGA as a biopesticide.

Metal-Organic Framework-Enabled Sustainable Agrotechnologies: An Overview of Fundamentals and Agricultural Applications

With aggravated abiotic and biotic stresses from increasing climate change, metal-organic frameworks (MOFs) have emerged as versatile toolboxes for developing environmentally friendly agrotechnologies aligned with agricultural practices and safety. Herein, we have explored MOF-based agrotechnologies, focusing on their intrinsic properties, such as structural and catalytic characteristics. Briefly, MOFs possess a sponge-like porous structure that can be easily stimulated by the external environment, facilitating the controlled release of agrochemicals, thus enabling precise delivery of agrochemicals. Additionally, MOFs offer the ability to remove or degrade certain pollutants by capturing them within their pores, facilitating the development of MOF-based remediation technologies for agricultural environments. Furthermore, the metal-organic hybrid nature of MOFs grants them abundant catalytic activities, encompassing photocatalysis, enzyme-mimicking catalysis, and electrocatalysis, allowing for the integration of MOFs into degradation and sensing agrotechnologies. Finally, the future challenges that MOFs face in agrotechnologies were proposed to promote the development of sustainable agriculture practices.

Infection of postharvest pear by Penicillium expansum is facilitated by the glycoside hydrolase (eglB) gene

The primary reason for postharvest loss is blue mold disease which is mainly caused by Penicillium expansum. Strategies for disease control greatly depend on the understanding of mechanisms of pathogen-fruit interaction. A member of the glycoside hydrolase family, β-glucosidase 1b (eglB), in P. expansum was significantly upregulated during postharvest pear infection. Glycoside hydrolases are a large group of enzymes that can degrade plant cell wall polymers. High homology was found between the glycoside hydrolase superfamily in P. expansum. Functional characterization and analysis of eglB were performed via gene knockout and complementation analysis. Although eglB deletion had no notable effect on P. expansum colony shape or microscopic morphology, it did reduce the production of fungal hyphae, thereby reducing P. expansum's sporulation and patulin (PAT) accumulation. Moreover, the deletion of eglB (ΔeglB) reduced P. expansum pathogenicity in pears. The growth, conidia production, PAT accumulation, and pathogenicity abilities of ΔeglB were restored to that of wild-type P. expansum by complementation of eglB (ΔeglB-C). These findings indicate that eglB contributes to P. expansum's development and pathogenicity. This research is a contribution to the identification of key effectors of fungal pathogenicity for use as targets in fruit safety strategies.

Carbendazim residue in plant-based foods in China: Consecutive surveys from 2011 to 2020

Carbendazim, a widely used fungicide in China, has been found to have reproductive toxicity and mutagenic effects. However, information on the spatial-temporal variations of carbendazim residues in food in China is limited. Here, we investigated the presence of carbendazim in China's plant-based foods from 2011 to 2020, evaluated the spatial-temporal characteristics, and assessed the associated exposure risks in the Chinese diet. The results revealed a high detection frequency of carbendazim in fruits (26.4%) and high concentrations in vegetables (∼110 mg kg-1), indicating widespread misuse of the fungicide. The acute risks of consuming certain vegetables and cereals exceeded the recommended limits by up to 12 and 5 times, respectively. Although there has been a decline in carbendazim residue levels in food since the implementation of the Chinese government's action plan for zero growth of pesticide use in 2015, some provinces still exhibited high levels of carbendazim in multiple food categories, which were positively correlated with annual pesticide application. We highlight that carbendazim contamination reflects the broader issue of pesticide use in China. It emphasizes the need for committed and targeted national policies to reduce carbendazim residues in food and suggests that such measures could also regulate the use of other pesticides, given that pesticide abuse in China is not limited to specific types. We call for the re-evaluation of maximum residue limits of carbendazim, particularly in highly consumed foods such as cereals.

Bimetallic CoCu nanoparticles anchored on COF/SWCNT for electrochemical detection of carbendazim

Carbendazim (CBZ) is a widespread fungicide used in crop protection, but the CBZ residues in drinking water, fruits, and vegetables can also cause adverse impacts on public health due to direct exposure. In this paper, a ternary synergistic composite of bimetallic CoCu nanoparticles anchored on covalent organic framework/single-walled carbon nanotube (CoCu/COF/SWCNT) was prepared and further applied as an electrochemical sensing platform for detecting CBZ. The sensor showed a sensitive response performance toward CBZ oxidation, as a result of the enhanced charge transfer ability, large electrochemically active surface area, and high electro-catalytic activity from the rational integration of the ternary components in CoCu/COF/SWCNT. Under the optimal conditions, the proposed sensor exhibited a detection range of 0.001 to 10 μM and a limit detection of 0.65 nM for CBZ detection. In addition, the sensor displayed practical feasibility for the determination of CBZ in water and pear samples with a recovery of 96.1 % to 102.1 %.

Linking Carbendazim Accumulation with Soil and Endophytic Microbial Community Diversities, Compositions, Functions, and Assemblies: Effects of Urea-hydrogen Peroxide and Nitrification Inhibitors

Fungicide carbendazim accumulation in soils and plants is a wide concern. Nitrogen (N) is a substantial nutrient limiting crop growth and affecting soil microbial activity and the community in degrading fungicides. We investigated the effects of urea-hydrogen peroxide (UHP) and nitrification inhibitors Dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP) on carbendazim accumulation and soil and endophytic microbial communities. The UHP application had negligible influences on soil and plant carbendazim accumulation, but the combined UHP and DCD decreased soil carbendazim accumulation by 5.31% and the combined UHP and DMPP decreased plant carbendazim accumulation by 44.36%. The combined UHP and nitrification inhibitor significantly decreased the ratios of soil Firmicutes and endophytic Ascomycota. Soil microbial community assembly was governed by the stochastic process, while the stochastic and deterministic processes governed the endophyte. Our findings could provide considerable methods to reduce fungicide accumulation in soil-plant systems with agricultural N management strategies.

A fast multi-residue analysis of twenty-four classes of pesticide in sesame (Sesamum indicum L.) and their migration into processed products

Sesame is widely used as a nutritional supplement or condiment because of its nutritious properties and palatable flavor. However, the extensive use of pesticides in sesame fields has paradoxically decreased the nutritional vantage. The current study used QuEChERS with a low-temperature freezing method to develop a multi-residue analytical approach to detect target analytes (pesticides) in sesame seed, sesame oil, sesame paste, and sesame meal. The migration ability of target pesticides during oil processing was investigated using HPLC-MS/MS and GC-MS: 35% of pesticides decreased, with processing factors (PFs) lower than 0.98, whereas 65% migrated from the seed to the oil during processing. The migration success of methoxyfenozide was the highest, while clothianidin and pymetrozine demonstrated a significantly lower rate of transfer. The results provide insight into the types of pesticides that should be used in farming practices of sesame to decrease the impact on human health.

Colletotrichum siamense, a Novel Causal Agent of Viburnum odoratissimum Leaf Blotch and Its Sensitivity to Fungicides

Viburnum odoratissimum Ker-Gawl is native to Asia and is usually used as a garden ornamental. In September 2022, a leaf blotch on V. odoratissimum was observed in Nanjing, Jiangsu, China. The disease causes the leaves of the plants to curl and dry up and defoliate early. It not only seriously affects the growth of the plants but also greatly reduces the ornamental value. The pathogenic fungus was isolated from the diseased leaves, and the fungus was identified to be Colletotrichum siamense based on morphological features and multilocus phylogenetic analyses of the internal transcribed spacer (ITS) region, actin (ACT), calmodulin (CAL), beta-tubulin 2 (TUB2), chitin synthase (CHS-1), Apn2-Mat1-2 intergenic spacer and partial mating type (ApMat), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes. Pathogenicity tests were performed by inoculating healthy leaves with conidia. C. siamense can grow at 15-35 °C, with an optimal growth temperature at 25-30 °C. The results of sensitivity to nine fungicides showed that C. siamense was the most sensitive to prochloraz in the concentration range of 0.01 μg/mL to 100 μg/mL. Therefore, spraying prochloraz before the optimum growth temperature of pathogenic fungus can achieve effective control. It provided useful information for future studies on the prevention and treatment strategies of C. siamense. This is the first report of leaf blotch caused by C. siamense on V. odoratissimum in China and worldwide.

Biotransformation of carbendazim in cowpea pickling process

Carbendazim, a systemic fungicide, is one of the most commonly detected pesticides in cowpeas. Pickled cowpea is a fermented vegetable product with unique flavor favored in China. The dissipation and degradation of carbendazim were investigated in the pickled process. The degradation rate constant of carbendazim in pickled cowpeas was 0.9945 and the half-life of the carbendazim was 14.06 ± 0.82 d. Seven transformation products (TPs) were identified in the pickled process. Furthermore, the toxicity of some TPs show more harmful to three aquatic organisms (TP134) and rats (all the identified TPs) than carbendazim. And most of the TPs posed more development toxicity and mutagenicity than carbendazim. 4 out of 7 TPs were discovered in the real pickled cowpea samples. These results shed light on the degradation and biotransformation of the carbendazim in the pickled process, to better understand the potential health risk of pickled food and evaluate the environmental pollution.

Mitigation of Hepatotoxicity via Boosting Antioxidants and Reducing Oxidative Stress and Inflammation in Carbendazim-Treated Rats Using Adiantum Capillus-Veneris L. Extract

Exposure to food contaminants continues to be a substantial source of human health risks all over the world, particularly in developing countries. Carbendazim (CBZ) is a chemical fungicide used to control the spread of various fungi and other pathogens in the agriculture and veterinary sectors. The hazardous effects of CBZ on human health occur due to the accumulation of its residues in agricultural food products. In this study, the possible hepatoprotective effects of Adiantum capillus-veneris L. (ACVL) extract were evaluated in CBZ-treated rats. A GC-MS analysis revealed that ACVL extract contained several bioactive hydrocarbon components and fatty acids, and that the components exerted hepatic protection by mitigating oxidative stress via upregulating antioxidant agents and neutralizing nitrogen and oxygen free radicals. Moreover, ACVL extracts relieved hepatic inflammation via decreasing NO, NF-κB, and pro-inflammatory cytokines (TNF-a, IL-6) in the liver of CBZ-treated rats, both at protein and mRNA levels. In addition, the protective effect of ACVL has appeared in the histopathological figures and function markers in the livers of CBZ-treated rats. According to the present results, ACVL extract can protect the hepatic tissue and restore its functions to a control level in CBZ-treated rats; this effect may be attributed to its antioxidant and anti-inflammatory activities.

Insights into enhanced toxic effects by the binary mixture of carbendazim and procymidone on hepatic lipid metabolism in mice

Carbendazim (CBZ) and procymidone (PRO) are two widely used fungicides in agriculture. However, there are still gaps in knowledge regarding about the potential hazards of joint exposure to CBZ and PRO in animals. Here, 6-week-old ICR mice were exposed to CBZ, PRO and CBZ + PRO for 30 days, and metabolomics were performed to discover the mechanism by which the mixture enhanced the effects on lipid metabolism. Co-exposure to CBZ + PRO elevated the body weights, relative liver weights and relative epididymis fat weights, but not in the single exposure groups. Molecular docking analysis suggested that CBZ and PRO combined with peroxisome proliferator-activated receptor (PPARγ) at the same amino acid site as the agonist rosiglitazone. The RT-qPCR and WB results demonstrated that the levels of PPARγ were higher in the co-exposure group than in the single exposure groups. In addition, hundreds of differential metabolites were discovered by metabolomics and enriched in different pathways, such as pentose phosphate pathway and purine metabolism. A unique effect, a decrease in glucose-6-phosphate (G6P) that promoted more NADPH production, was observed in the CBZ + PRO group. These results demonstrated that exposure to CBZ + PRO caused more serious lipid metabolism disorder in the liver than exposure to a single fungicide, which could provide some new insight for the toxic effects after fungicides joint exposure.

Antifungal Activity of Perillaldehyde on Fusarium solani and Its Control Effect on Postharvest Decay of Sweet Potatoes

Root rot caused by Fusarium solani is one of the major postharvest diseases limiting sweet potato production. Here, antifungal activity and the action mode of perillaldehyde (PAE) against F. solani were investigated. A PAE concentration of 0.15 mL/L in air (mL/L air) markedly inhibited the mycelial growth, spore reproduction and spore viability of F. solani. A PAE vapor of 0.25 mL/L in air could control the F. solani development in sweet potatoes during storage for 9 days at 28 °C. Moreover, the results of a flow cytometer demonstrated that PAE drove an increase in cell membrane permeability, reduction of mitochondrial membrane potential (MMP) and accumulation of reactive oxygen species (ROS) in F. solani spores. Subsequently, a fluorescence microscopy assay demonstrated that PAE caused serious damage to the cell nuclei in F. solani by inducing chromatin condensation. Further, the spread plate method showed that the spore survival rate was negatively correlated with the level of ROS and nuclear damage, of which the results indicated that PAE-driven ROS accumulation plays a critical role in contributing to cell death in F. solani. In all, the results revealed a specific antifungal mechanism of PAE against F. solani, and suggest that PAE could be a useful fumigant for controlling the postharvest diseases of sweet potatoes.

Carbendazim: Ecological risks, toxicities, degradation pathways and potential risks to human health

Carbendazim is a highly effective benzimidazole fungicide and is widely used throughout the world. The effects of carbendazim contamination on the biology and environment should be paid more attention. We reviewed the published papers to evaluate the biological and environmental risks of carbendazim residues. The carbendazim has been frequently detected in the soil, water, air, and food samples and disrupted the soil and water ecosystem balances and functions. The carbendazim could induce embryonic, reproductive, developmental and hematological toxicities to different model animals. The carbendazim contamination can be remediated by photodegradation and chemical and microbial degradation. The carbendazim could enter into human body through food, drinking water and skin contact. Most of the existing studies were completed in the laboratory, and further studies should be conducted to reveal the effects of successive carbendazim applications in the field.

Different dissipation potential and dietary risk assessment of tristyrylphenol ethoxylates in cowpea ecosystem in China

Tristyrylphenol ethoxylates (TSPEOn) are widely used as inert ingredients in pesticide formulations in the world. However, the information on the dissipation behavior of different homologs TSPEOn in agro-products is lacking. To investigate the dissipation behavior of TSPEOn, a cowpea field experiment treated with TSPEOn at different doses was carried out in Guangdong province, China. Different 24 TSPEO homologs were all detected in cowpea from the field terminal residue experiments, and the total concentrations of TSPEO homologs in cowpea were 40.0–1,374 μg/kg. The dissipation half-lives of 24 TSPEO homologs in soil were 1.51–2.35 times longer than those in cowpea. The long-chain homologs TSPEOn were dissipated faster than the short-chain homologs TSPEOn, suggesting a homolog-specific degradation of the TSPEOn in the cowpea ecosystem. The characteristic bimodal profiles of TSPEOn (n = 6–29) differing from that of the commercial TSPEOn were observed in the cowpea terminal residues experiment, indicating that the long-chain TSPEOn would degrade to short-chain TSPEOn in cowpea and soil. The acute and chronic dietary exposure risks of ΣTSPEOn in cowpea are within acceptable margins for human consumption across different ages and genders. But the health risks to children should be noticed in future.

Carbendazim toxicity in different cell lines and mammalian tissues

The extensive production and use of harmful pesticides in agriculture to improve crop yield has raised concerns about their potential threat to living components of the environment. Pesticides cause serious environmental and health problems both to humans and animals. Carbendazim (CBZ) is a broad spectrum fungicide that is used to control or effectively kill pathogenic microorganisms. CBZ is a significant contaminant found in food, soil and water. It exerts immediate and delayed harmful effects on humans, invertebrates, aquatic animals and soil microbes when used extensively and repeatedly. CBZ is a teratogenic, mutagenic and aneugenic agent that imparts its toxicity by enhancing generation of reactive oxygen species generation. It elevates the oxidation of thiols, proteins and lipids and decreases the activities of antioxidant enzymes. CBZ is cytotoxic causing hematological abnormalities, mitotic spindle deformity, inhibits mitosis and alters cell cycle events which lead to apoptosis. CBZ is known to cause endocrine-disruption, embryo toxicity, infertility, hepatic dysfunction and has been reported to be one of the leading causes of neurodegenerative disorders. CBZ is dangerous to human health, the most common side effects upon chronic exposure are thyroid gland dysfunction and oxidative hepato-nephrotoxicity. In mammals, CBZ has been shown to disrupt the antioxidant defense system. In this review, CBZ-induced toxicity in different cells, tissues and organisms, under in vitro and in vivo conditions, has been systematically discussed.

Profiling of pesticides and pesticide transformation products in Chinese herbal teas

Herbal teas have potential health benefits, but they also contain a variety of pesticides and pesticide transformation products (PTPs) that might brings health risks. Our study maps the pesticides and PTPs in two herbal teas (chrysanthemum and Lusterleaf Holly) from two main producing areas in China. Almost all 122 samples contain pesticides, with concentration ranging from 0.0005 to 10.305 mg/kg. Nearly 40% carbendazim and imidacloprid in chrysanthemum teas and λ-cyhalothrin in Lusterleaf Holly have higher concentration levels than the values permitted in EC Regulation No. 396/2005. Distinct distributions of pesticides were found in different teas and production areas. Eight PTPs were identified along with their parents, and were confirmed using a biosynthetic strategy. Acute, chronic and cumulative health risk assessments of pesticides revealed acceptable results. Our study uncovers the profile of pesticides in herbal teas, and provides new insight into discovering the potential environmental pollution and food contaminants.

DFT insights into the degradation mechanism of carbendazim by hydroxyl radicals in aqueous solution

Advanced oxidation of carbendazim by OH radicals is a central step in its wastewater remediation. However, the understanding of the degradation mechanism of carbendazim has always been a challenge. In this paper, the degradation mechanism of carbendazim by •OH in aqueous solution has been explored using density functional theory (DFT) calculations. On account of the structural and electronic characteristics analysis, the nucleophilic aromatic substitution, dehydrogenation oxidation, and decarboxylation degradation pathways were mainly investigated. These degradation reactions may produce hydroxyl substitution products, oxidized aldehyde and carboxyl products, and decarboxylated carbamic acid products. Computational studies demonstrated that these possible degradation reactions are facile to take place kinetically and have large thermodynamic driving forces, indicating the feasibility of the relevant degradation pathways. Additionally, the ecological risk of carbendazim and its possible degradation products was evaluated, showing that the acute toxicity of degradation products decreases in varying degrees compared with that of carbendazim. The comprehensive mechanistic studies open an avenue for the understanding on the degradation of organic pollutants such as benzimidazole pollutants on molecular level.

Metabolic Activation and Cytotoxicity of Fungicide Carbendazim Mediated by CYP1A2

Carbendazim (CBZ) is a broad-spectrum fungicide widely used in many nations for foliar spray as well as seed and soil treatment. The resulting contamination and environmental pollution have been drawing public attention. In particular, CBZ was reported to cause liver damage in rats and zebrafish, and the mechanisms of its toxicity have not been clarified. The purposes of this study were to investigate the metabolic activation of CBZ and to determine a possible role of the reactive metabolites in CBZ-induced liver injury reported. One oxidative metabolite (M1), one glutathione conjugate (M2), and one N-acetyl cysteine conjugate (M3) were detected in human and rat liver microsomal incubations fortified with glutathione or N-acetyl cysteine after exposure to CBZ. CYP1A2 was the major enzyme responsible for the metabolic activation of CBZ. Biliary M2 and urinary M3 were detected in rats treated with CBZ. CBZ-derived protein adduction was found in cultured rat primary hepatocytes treated with CBZ. The increase of administration concentration intensified not only the cytotoxicity but also protein adduction induced by CBZ, suggesting a correlation of the cytotoxicity with the observed protein modification. The findings facilitate the understanding of the mechanisms of toxic action of CBZ.

Dissipation behaviour, residue analysis, and dietary safety evaluation of chlorfenapyr on various vegetables in China

Chlorfenapyr has been widely used in recent years to control a variety of pests on fruit and vegetables. Cabbage, leek, asparagus, and chive are four of the most common green foods consumed word wide; their pesticide residue issues have also received more attention. Therefore, studies on the residue analysis, degradation evaluation and dietary risk assessment based on the complete residue definition of chlorfenapyr on these four vegetables were essential and urgently needed. A reliable analytical method was developed and applied to simultaneously determine the content of chlorfenapyr and its metabolite tralopyril residues on the four vegetables. Recoveries were satisfactory (84%-110% for chlorfenapyr; 83%-106% for tralopyril) at a spiked level of 0.01-1 mg/kg, with intraday precision (n = 5) and interday precision (n = 15) ranging from 1.6% to 8.9% and from 2.4% to 9.1%, respectively. The limits of quantification (LOQs) were all 0.01 mg/kg. On the basis of supervised field trials, the degradation half-lives of chlorfenapyr were 1.2-9.8 days. Chlorfenapyr rapidly degraded on asparagus, but persisted much longer on chive. The terminal concentration of chlorfenapyr residues varied from <0.01 to 0.84 mg/kg. Additionally, the risk quotients (RQs) ranged from 4.7% to 13.8%, suggesting that chlorfenapyr had a negligible risk for chronic dietary intake of these crops. This study was thus significant in evaluating the degradation rate and quality safety of chlorfenapyr on various vegetables and promoted the development of maximum residue limits.

Dissipation and dietary risk assessment of carbendazim and epoxiconazole in citrus fruits in China

BACKGROUND

Carbendazim and epoxiconazole are widely applied to control anthracnose and sand bark fungal diseases in citrus. The residues of these two fungicides in citrus and their potential risk to consumers have generated much public concern. We therefore sought to investigate the dissipation, residue, and dietary risk assessment of carbendazim and epoxiconazole in citrus.

RESULTS

The dissipation kinetics and residue levels of carbendazim and epoxiconazole in citrus under field conditions were measured using dispersive solid-phase extraction and ultra-high-performance liquid chromatography-tandem mass spectrometry. The citrus samples were extracted with acetonitrile and purified by primary secondary amine sorbent. The mean recoveries of carbendazim and epoxiconazole ranged from 86.2 to 105.6% and relative standard deviations were ≤9.8%. The half-lives of carbendazim and epoxiconazole in whole citrus ranged from 2.0 to 18.0 days. Hazard quotient (HQ) and risk quotient (RQ) models were applied to whole citrus for dietary exposure risk assessment based on the terminal residue test. Hazard quotients ranged from 0.066 to 0.134% and RQs from 18.48 to 82.12%.

CONCLUSION

Carbendazim and epoxiconazole in citrus degraded rapidly following first-order kinetics models. The dietary risk of exposure to both carbendazim and epoxiconazole through citrus, based on HQ and RQ, was acceptable for human consumption. This study indicates scientifically validated maximum residue limits in citrus, which are currently lacking for epoxiconazole in China. © 2021 Society of Chemical Industry.

Degradation of Carbendazim by Molecular Hydrogen on Leaf Models

Although molecular hydrogen can alleviate herbicide paraquat and Fusarium mycotoxins toxicity in plants and animals, whether or how molecular hydrogen influences pesticide residues in plants is not clear. Here, pot experiments in greenhouse revealed that degradation of carbendazim (a benzimidazole pesticide) in leaves could be positively stimulated by molecular hydrogen, either exogenously applied or with genetic manipulation. Pharmacological and genetic increased hydrogen gas could increase glutathione metabolism and thereafter carbendazim degradation, both of which were abolished by the removal of endogenous glutathione with its synthetic inhibitor, in both tomato and in transgenic Arabidopsis when overexpressing the hydrogenase 1 gene from Chlamydomonas reinhardtii. Importantly, the antifungal effect of carbendazim in tomato plants was not obviously altered regardless of molecular hydrogen addition. The contribution of glutathione-related detoxification mechanism achieved by molecular hydrogen was confirmed. Our results might not only illustrate a previously undescribed function of molecular hydrogen in plants, but also provide an environmental-friendly approach for the effective elimination or reduction of pesticides residues in crops when grown in pesticides-overused environmental conditions.

Application, advancement and green aspects of magnetic molecularly imprinted polymers in pesticide residue detection

Molecularly imprinted polymers (MIPs) have added a vital contribution to food quality and safety with the effective extraction of pesticide residues due to their unique properties. Magnetic molecularly imprinted polymers (MMIPs) are a superior approach to overcome stereotypical limitations due to their unique core-shell and novel composite structure, including high chemothermal stability, rapid extraction, and high selectivity. Over the past two decades, different MMIPs have been developed for pesticide extraction in actual food samples with a complex matrix. Nevertheless, such developments are desirable, yet the synthesis and mode of application of MMIP have great potential as a green chemistry approach that can significantly reduce environmental pollution and minimize resource utilization. In this review, the MMIP application for single or multipesticide detection has been summarized by critiquing each method's uniqueness and efficiency in real sample analysis and providing a possible green chemistry exploration procedure for MMIP synthesis and application for escalated food and environmental safety.

Wearable sensors made with solution-blow spinning poly(lactic acid) for non-enzymatic pesticide detection in agriculture and food safety

On-site monitoring the presence of pesticides on crops and food samples is essential for precision and post-harvest agriculture, which demands nondestructive analytical methods for rapid, low-cost detection that is not achievable with gold standard methods. The synergy between eco-friendly substrates and printed devices may lead to wearable sensors for decentralized analysis of pesticides in precision agriculture. In this paper we report on a wearable non-enzymatic electrochemical sensor capable of detecting carbamate and bipyridinium pesticides on the surface of agricultural and food samples. The low-cost devices (<US$ 0.08 per unit) contained three-electrode systems deposited via screen-printing technology (SPE) on solution-blow spinning mats of poly (lactic acid) (PLA). The flexible PLA/SPE sensors can be used on flat, curved and irregular surfaces of leaves, vegetables and fruits. Detection was performed using differential pulse voltammetry and square wave voltammetry with detection limits of 43 and 57 nM for carbendazim and diquat, respectively. The wearable non-enzymatic sensor can discriminate and quantify carbendazim and diquat on apple and cabbage skins with no interference from other pesticides. The use of such wearable sensors may be extended to other agrochemicals, including with incorporation of active bio (sensing) layers for online monitoring of any type of agricultural products and foods.

Antagonistic Effects of Enrofloxacin on Carbendazim-Induced Developmental Toxicity in Zebrafish Embryos

Carbendazim (CAR) and enrofloxacin (ENF) are frequently detected in fruits and meat products, respectively. Since most people consume fruits, vegetables, and meat products, combined exposure is possible, necessitating further evaluation of toxic interactions. In this study, the developmental toxicity of separate and combined exposure was examined in zebrafish embryos. Carbendazim exposure at 0.79 mg/L and above significantly affected developmental parameters, while enrofloxacin alone had no substantial effects on these developmental parameters within the selected concentration range (0.10-0.40 mg/L). Surprisingly, ENF antagonized the CAR-evoked reduction in the 48 hpf (hours post-fertilization) hatching rate and the increases in the 96 hpf malformation and lethality rates. The results revealed that the antagonism might be associated with reciprocal effects of these compounds on metabolism-related genes, such as cyp7a1 and apoa1a. These results reveal a complex interaction between ENF and CAR on metabolic regulation during development and highlight the importance of combined assessment for agents with the potential for simultaneous exposure.

Individual and synergistic toxic effects of carbendazim and chlorpyrifos on zebrafish embryonic development

The fungicide carbendazim and the insecticide chlorpyrifos are frequently used together to protect various fruit and vegetable crops in China. At high doses, carbendazim is a known carcinogen while chlorpyrifos has neurotoxic potential, but the combined toxicity of these two compounds has not been systematically investigated. In this study, we examined the separate and combined effects of these compounds on zebrafish embryonic development. The LC₅₀ values for carbendazim and chlorpyrifos at 96 h post-fertilization (hpf) were 0.89 mg/L and 3.83 mg/L, respectively. Carbendazim dose-dependently increased the spontaneous tail-wagging frequency of 24 hpf embryos, the hatching rate of 48 hpf embryos, and the mortality and deformity rate of 96 hpf embryos, while chlorpyrifos increased the heart rate of 48 hpf embryos as well as the mortality and deformity rate of 96 hpf embryos. Mixed exposure at an equipotent concentration ratio (Mix1) and at the ratio of maximum residue limits for typical fruits (apples) (Mix2) revealed significant synergistic effects on lethality at 96 hpf within the 0%-90% effect levels range. In contrast, there was an antagonistic effect of the equipotent concentration ratio on lethality in the 90%-100% concentration range, while the ratio at the maximum residue limits still showed a synergistic effect. Mix1 exhibited antagonism on hatching rate in the 0%-35% range and synergy in the 40%-100% range, while Mix2 had a synergistic effect on hatching rate in the 0%-35% range, an additive effect at 40%, and an antagonistic effect at >40%. Both mixtures had a synergistic effect on deformity rate over all concentration ranges. Carbendazim and chlorpyrifos demonstrate synergistic developmental toxicity, indicating that health and environmental risk assessments should be conducted for various combinations of these agents.

Chromatographic Methods for Detection and Quantification of Carbendazim in Food

Carbendazim (CBZ), which is a fungicide widely used for the management of plant diseases, has been detected in a number of food products. The negative effects of CBZ to human health have stimulated the reduction of the maximum residue limits (MRLs), and subsequently the development of reliable and sensitive detection methods. Here, we are reviewing for the first time all reported chromatographic methods for the detection and quantification of CBZ in food. Several techniques, including liquid chromatography (LC), thin layer chromatography (TLC), micellar electrokinetic chromatography (MEKC), and supercritical fluid chromatography (SFC), were used for the separation and detection of CBZ, showing diverse characteristics and sensitivity. Some methods allowed the specific determination of CBZ, whereas other methods were successfully applied for the simultaneous quantification of a huge number of pesticides. Most reported methods showed limits of detection (LOD) and quantification (LOQ) lower than the MRLs. Relevant efforts in the field have been directed toward the simplification and optimization of the extraction steps prior to the chromatographic separation to increase the recovery and reduce the matrix effects. In this Review, the matrices, extraction procedures, and separation and detection parameters are detailed and compared in order to provide new insights on the development of new reliable methods for the detection of CBZ in food.

Sub-chronic carbendazim exposure induces hepatic glycolipid metabolism disorder accompanied by gut microbiota dysbiosis in adult zebrafish (Daino rerio)

Carbendazim (CBZ) as a broad spectrum fungicide is widely used in the whole world to contorl plant diseases. With the application of CBZ in the agriculture, it has been detected in vegetables and fruits. Nowadays, it even has been detected in the watercourse and indoor dust. However, the toxic effects of CBZ on aquatic organisms have received limited attention. In this study, male adult zebrafish were exposed at 0, 30 and 100 μg/L CBZ for 21 days to assess its effects on hepatic glycolipid metabolism. After exposure, the body weight and length decreased, but the condition factor increased significantly. Some hepatic biochemical parameters including the levels of glucose, pyruvate, low density lipoprotein (LDL) and triglyceride (TG) decreased significantly in the liver of zebrafish after exposure with CBZ. Two transaminases alanine transaminase (ALT) and aspartate transaminase (AST) also increased significantly, indicating that subchronic CBZ exposure influenced the liver function. Moreover, the relative mRNA levels of some key genes related to the glycolysis and lipid metabolism in the liver also changed significantly. Furthermore, the transcriptome analysis showed that the carbon metabolism, lipid metabolism and detoxification metabolism were also affected in the liver of CBZ exposed zebrafish. Interestingly, we also found the amounts of the Firmicutes, Bacteroidetes, Actinobacteria, α-Proteobacteria, γ-Proteobacteria and Verrucomicrobia at phylum level significantly decreased in the gut. Sequencing V3-V4 region of 16S rRNA also demonstrated gut microbiota composition changed significantly according to weighted UniFrac distance analysis. Consequently, subchronic CBZ exposure induced hepatic metabolic disorder accompanied by gut microbiota dysbiosis in adult male zebrafish.

Occurrence of pesticides residues in French beans, tomatoes, and kale in Kenya, and their human health risk indicators

Residue levels of seven commonly used pesticides were determined in random samples of tomatoes, French beans, and kale collected from horticultural farms in Buuri, Imenti North, and Imenti South sub-counties in Meru, Kenya, just before delivery to the consumers. QuEChERS method for extraction followed by LC-MS/MS was used to determine the concentrations. The concentrations (μg kg^-1 wet weight) in French beans, kale, and tomatoes ranged from below detection limit (BDL): BDL-48.65 (carbendazim), BDL-290.76 (imidacloprid), BDL-2.81 (acetamiprid), BDL-25.76 (azoxystrobin), BDL-105.18 (metalaxyl), BDL-0.15 (diazinon), and BDL-0.17(chlorpyrifos). The maximum residue levels determined in the horticultural produce from the three regions were 290 μg kg^-1 for imidacloprid in tomatoes from Buuri and 25.76 μg kg^-1for azoxystrobin in French beans from Imenti South. The pesticide residue levels generally were extremely low and met the MRLs set by EU and other countries, except for carbendazim and metalaxyl in French beans, and posed no concern to human health. The estimated daily intakes (EDI) (mg kg^-1 BW/day) for the population of Meru County were very low ranging from 1.685 × 10^-8 (acetamiprid) to 2.381 × 10^-5 (imidacloprid) in tomatoes, 2.849 × 10^-9 (metalaxyl) to 3.633 × 10^-7 (azoxystrobin) in French beans, and 1.392 × 10^-8 (diazinon) in kale, respectively. The health risk indices were subsequently extremely low for the detectable pesticide residues, ranging from 6.74 × 10^-7 (acetamiprid) to 3.97 × 10^-4 (imidacloprid) in tomatoes, 3.56 × 10^-8 (metalaxyl) to 5.52 × 10^-5 (chlorpyrifos) in French beans, and 6.96 × 10^-5 (diazinon) in kale, respectively, indicating no health risk in the population, but their presence in these vegetables cannot be ignored as long-term exposure can still cause health risks.

Effects of carbendazim on catalase activity and related mechanism

The different techniques like spectroscopy and fluorescence quenching were used to study the interactive effect of carbendazim (CARB) and catalase (CAT) at the molecular level. The results showed that conditions were beneficial to the quenching mechanism at 25.0 °C, pH 7.0, while the binding constant k was 1.92 × 10⁵ L mol^-1 and the number of binding site was 1.0385. The thermodynamic parameters indicated that CARB could interact spontaneously with CAT to form a complex mainly by van der Waals' interactions and hydrogen bonds. The interaction mechanism between CARB and CAT was that the effects of CARB on CAT in soil were activated and then restore stability. However, the effects of CARB on simple CAT were activated and then inhibited.

Distribution of residual agricultural pesticides and their impact assessment on the survival of an endangered species

This study aimed to assess the distribution of spent pesticides in an agro-farming area and to evaluate their impact on the ecological risk for an endangered species combing the health risk assessment concept with the modelling algorithm proposed by European Food Safety Authority (EFSA). An agricultural area in western Taiwan was chosen to investigate the ecological risk on Prionailurus bengalensis. Their ecological stability was evaluated in the context of the residuals' distribution of the spent pesticides in the investigated area. The pesticide residues accumulated and correlated highly to the adverse health impact on the leopard cat. In the present study, 67 pesticides were detected from 79 collected soil samples. The hazard index (HI) was found related to land use patterns and the HI values in Yuanli and Zhuolan were significantly higher than those in the other areas, increasing poisoning probability of the leopard cat. The locations of agro-chemical utilization were highly overlapped with leopard cats' activity zone, supporting the hypothesis that pesticide residues posed a potential threat to the leopard cats' health. The proposed risk assessment framework was capable of estimating the risk caused by pesticide residues and no similar study has been reported before.