Analysis of exposure to pesticide residues from Traditional Chinese Medicine

Advances in sample preparation methods for pesticide residue analysis in medicinal plants: A focus on Nepal

Medicinal plant safety is a rising challenge worldwide due to the continued overuse of pesticides to their maximum residue limits. Due to the high demand for medicinal plants, their production is being increased and sometimes protected by pesticide use. The analysis of these residues requires robust analytical methods to ensure the safety and quality of medicinal plants. Developing effective sample preparation for detecting pesticides is challenging, due to their diverse natures, classes, and physico-chemical characteristics. Hence, existing techniques and strategies are needed to improve the reliability of the results. The review discusses the current state of sample preparation techniques, analytical methods, and instrumental technologies employed in pesticide residue analysis in medicinal plants. It highlights the challenges, limitations, and advancements in the field, providing insights into the analytical strategies used to detect and quantify pesticide residues. Reliable, accessible, affordable, and high-resolution analytical procedures are essential to ensure that pesticide levels in medicinal plants are effectively regulated. By understanding the complexities of pesticide residue analysis in medicinal plants, this review article aims to support the conservation of medicinal plant resources, promote public health, and contribute to the development of sustainable strategies for ensuring the safety and quality of medicinal plants in Nepal. The findings of this review will benefit researchers, policymakers, and stakeholders involved in the conservation of medicinal plant resources and the promotion of public health.

Exploring the Potential of Biochar Derived from Chinese Herbal Medicine Residue for Efficient Removal of Norfloxacin

One-step carbonization was explored to prepare biochar using the residue of a traditional Chinese herbal medicine, Atropa belladonna L. (ABL), as the raw material. The resulting biochar, known as ABLB4, was evaluated for its potential as a sustainable material for norfloxacin (NOR) adsorption in water. Subsequently, a comprehensive analysis of adsorption isotherms, kinetics, and thermodynamics was conducted through batch adsorption experiments. The maximum calculated NOR adsorption capacity was 252.0 mg/g at 298 K, and the spontaneous and exothermic adsorption of NOR on ABLB4 could be better suited to a pseudo-first-order kinetic model and Langmuir model. The adsorption process observed is influenced by pore diffusion, π-π interaction, electrostatic interaction, and hydrogen bonding between ABLB4 and NOR molecules. Moreover, the utilization of response surface modeling (RSM) facilitated the optimization of the removal efficiency of NOR, yielding a maximum removal rate of 97.4% at a temperature of 304.8 K, an initial concentration of 67.1 mg/L, and a pH of 7.4. Furthermore, the biochar demonstrated favorable economic advantages, with a payback of 852.5 USD/t. More importantly, even after undergoing five cycles, ABLB4 exhibited a consistently high NOR removal rate, indicating its significant potential for application in NOR adsorption.

Quality and production enhancement of fish mint, Houttuynia cordata Thunb., cultivated in a hydroponic planting system with designed plant growth-promoting additives

Fish mint, Houttuynia cordata Thunb. (HCT) is an edible vegetable that has also been used in traditional folk medicines. As both a medicinal herb and a dietary source, HCT has been clinically proven to be a pivotal ingredient in formulas administered to alleviate COVID-19 symptoms. With the increasing market demand for imported materials, ensuring the quality consistency of HCT becomes a significant concern. In this study, the growing time for hydroponically-cultivated HCT with seaweed extract and amino acids added (HCTW) reduced by half compared to conventional soil-cultivated HCT (HCTS). Key quantified components in HCTW, flavonoid glycosides and caffeoylquinic acid derivatives, exhibited a 143% increase over HCTS. These crucial constituents were responsible for possessing antioxidant activity (IC50 < 25 μg/mL) and anti-nitrite oxide production (IC50 < 20 μg/mL). An economically-designed hydroponic system with appropriate additives is proposed to replace HCTS with improvements of growth time, overall production yields, and bioactive qualities.

Transport and interaction mechanism of four pesticide residues from Chaenomeles speciosa across Caco-2 cells

The presence of multiple pesticide residues in agricultural production highlights the need for studying mixture interaction during transepithelial transport. This study applied the Caco-2 cell model to investigate the interaction of four pesticide residues (carbendazim, epoxiconazole, phoxim, and chlorpyrifos) in Chaenomeles speciosa during transepithelial transport. Results demonstrated that co-treatment with pesticide mixtures generally increased the cumulative transport amount of carbendazim and epoxiconazole by 0.32-1.60 times and 0.32-0.98 times, respectively, compared to individual treatments. Notably, the combination of carbendazim and epoxiconazole displayed a significant synergistic effect. The use of transporter inhibitors and molecular docking analysis provided insights into the interaction mechanism, suggesting that the competitive inhibition of MRP2 and/or BCRP binding via π-bonds contributed to the inhibition of BL-to-AP efflux and a significant increase in AP-to-BL influx of carbendazim and epoxiconazole. The results are of great theoretical significance and practical value for risk assessment of multiple pesticide residues in agricultural products.

Multi-residue monitoring and dietary risk assessment of 17 pesticides and 3 related metabolites in rice and rice flour from markets in China

Pesticide residues in rice have attracted widespread public attention in recent years. This research aimed to monitor the residues of 17 pesticides and their 3 metabolites in 120 samples of rice and rice flour collected from markets in China using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) pretreatment method combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The monitoring results showed that isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in the rice samples, with detection frequencies of 33.3%, 17.5%, 8.3%, and 2.5%, and concentrations ranging from 0.02 to 0.1 mg/kg (median = 0.04), 0.01 to 0.17 mg/kg (median = 0.14), 0.04 to 0.06 mg/kg (median = 0.05), and 0.01 to 0.02 mg/kg (median = 0.01), respectively. The residues of these four pesticides were all below their corresponding maximum residue levels (MRLs) set by China. Additionally, isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in rice flour samples, with detection frequencies of 74.2%, 55.0%, 5.0%, and 2.5%, and concentrations ranging from 0.01 to 0.1 mg/kg (median = 0.04), 0.01 to 0.04 mg/kg (median = 0.02), 0.01 to 0.06 mg/kg (median = 0.03), and 0.02 to 0.04 mg/kg (median = 0.03), respectively. Furthermore, the chronic dietary intake risk (HQc), the acute dietary intake risk (HQa), and cumulative dietary risk (HI) for all the detected pesticides were evaluated and found well below 100%, indicating that the dietary intake risks would not pose potential health risks.

Neonicotinoids in tea leaves and infusions from China: Implications for human exposure

The ingestion of contaminated tea involves the risk of human exposure to residues of neonicotinoids (NEOs). Nevertheless, there is little empirical research about this topic; to bridge the current knowledge gap, we collected 220 samples of various tea products from four geographical areas in China, including unfermented green tea, semi-fermented white tea and oolong tea, completely fermented black tea, and post-fermented dark tea. A total of six NEOs were detected from the tea leaves and infusions, namely, dinotefuran (DIN), thiamethoxam (THM), clothianidin (CLO), imidacloprid (IMI), acetamiprid (ACE), and thiacloprid (THI). The detection frequencies (DFs) and concentrations of all target NEOs were relatively high across the investigated tea samples, and the DIN, IMI and ACE residues measured in some samples exceeded the maximum residue level (MRL) standards for the European Union. Samples representing the Jiangnan area exhibited greater levels of total target NEOs (∑6NEOs) than samples representing the Jiangbei area (p < 0.001). Moreover, dark tea samples were found to have far higher levels of NEO residues than green (p < 0.001), white (p < 0.05), or oolong (p < 0.001) samples. The health risks associated with exposure to NEO residues via tea were small for both children and adults in terms of acute, chronic, and cumulative dietary exposure risk assessments. The transfer rates (TRs) of NEOs observed in white, black, and dark tea infusions gradually decreased after the third brewing time. As such, it is recommended to only consume tea that has been brewed at least three times. The presented results not only describe the extent of NEO contamination in Chinese tea leaves and infusions, but also provide tea drinking guidelines for consumers.

Residue Analysis and Dietary Risk Assessment of Pymetrozine in Potato (Solanum tuberosum L.) and Chrysanthemum morifolium (Ramat)

Pymetrozine is used on potato (S. tuberosum) and Chrysanthemum morifolium (C. morifolium) to obtain greater yield and quality. However, pesticide use carries the potential for residues to remain and be detected on harvested crops. Therefore, the aim of this study was to estimate pesticide residues in S. tuberosum and C. morifolium products that are commercially available for human consumption and to assess the associated dietary risks. For this study, a total of 340 samples (200 S. tuberosum samples and 140 C. morifolium samples) were collected randomly from supermarkets and farmer's markets. Residues of pymetrozine in S. tuberosum and C. morifolium were detected by using an established and validated QuECHERS-HPLC-MS / MS method, while a dietary risk assessment of pymetrozine in S. tuberosum and C. morifolium was performed using these data. The detection rates of pymetrozine in S. tuberosum and C. morifolium samples were 92.31% and 98.17%, respectively, with residues not more than 0.036 and 0.024 mg/kg, respectively. Based on these results, the dietary risk assessment indicated that the intake of pymetrozine residues in S. tuberosum and C. morifolium does not pose a health risk. This work improved our understanding of the potential exposure risk of pymetrozine in S. tuberosum and C. morifolium.

Risk assessment of honeybee larvae exposure to pyrethroid insecticides in beebread and honey

Honeybee is an essential pollinator to crops, evaluation to the risk assessment of honeybee larvae exposure to pesticides residue in the bee bread and honey is an important strategy to protect the bee colony due to the mixture of these two matrices is main food for 3-day-old honeybee larvae. In this study, a continuous survey to the residue of five pyrethroid insecticides in bee bread and honey between 2018 and 2020 from 17 major cultivation provinces which can be determined as Northeast, Northwest, Eastern, Central, Southwest, and Southern of China, there was at least one type II pyrethroid insecticide was detected in 54.7 % of the bee bread samples and 43.4 % of the honey. Then, we assayed the acute toxicity of type II pyrethroid insecticides based on the detection results, the LD50 value was 0.2201 μg/larva (beta-cyhalothrin), 0.4507 μg/larva (bifenthrin), 2.0840 μg/larva (fenvalerate), 0.0530 μg/larva (deltamethrin), and 0.1640 μg/larva (beta-cypermethrin), respectively. Finally, the hazard quotient was calculated as larval oral ranged from 0.046 × 10-3 to 2.128 × 10-3. Together, these empirical findings provide further insight into the accurate contamination of honey bee colonies caused by chemical pesticides, which can be used as a valuable guidance for the beekeeping industry and pesticide regulation.

Multiple pesticide residues and risk assessment of Dendrobium officinale Kimura et Migo: a three-year investigation

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicine homologous to food, and its safety has attracted considerable attention. Pesticide residues are critical indicators for evaluating the safety of D. officinale. This study investigated the levels of 130 pesticides in 137 stem samples and 82 leaf samples from five main production areas of D. officinale in Zhejiang Province, along with the associated risk of dietary exposure for the population between 2019 and 2021. Forty-five pesticides were detected in 171 samples, of which pyraclostrobin had the highest detection frequency. Multiple residues were detected in 52.56% of the stem samples and 54.88% of the leaf samples, and one stem sample contained up to 18 pesticides. Here, the level of difenoconazole in three samples (two stem samples and one leaf sample) was higher than the maximum residue limit (MRL) in China. Considering the possible health risks related to pesticide residues, a risk assessment of human exposure to pesticides via the intake of D. officinale stems and leaves was evaluated, indicating negligible short-term, long-term, and cumulative risks to human health. However, considering the high detection rate of unregistered pesticides, the supplementation of pesticide registration information on D. officinale should be expedited, and MRLs should be established to ensure food and drug safety.

Dissipation Behavior and Dietary Risk Assessment of Thiamethoxam, Pyraclostrobin, and Their Metabolites in Home-Style Pickled Cowpea

In this study, the fate of two pesticides commonly used on cowpeas, thiamethoxam and pyraclostrobin, during the preparation of home-made pickled cowpeas was investigated using an improved QuEChERS method combined with UHPLC-MS/MS. Although pesticide residues were primarily distributed on cowpea samples, some were transferred to brine. The dissipation half-life of thiamethoxam on cowpea samples was significantly shorter than that of pyraclostrobin due to thiamethoxam's higher water solubility. Thiamethoxam demonstrated a half-life of 5.12 ± 0.66 days, whereas pyraclostrobin exhibited a longer half-life of 71.46 ± 7.87 days. In addition, the degradation half-lives of these two pesticides in the whole system (cowpea and brine) were 45.01 ± 4.99 and 70.51 ± 5.91 days, respectively. This result indicates that the pickling did not effectively promote the degradation of thiamethoxam and pyraclostrobin. The metabolite clothianidin of thiamethoxam was not produced throughout the pickling process, but the metabolite BF 500-3 of pyraclostrobin was detected in cowpea samples. The detection rates for thiamethoxam, pyraclostrobin, and BF 500-3 in the 20 market samples were 10%, 70%, and 45%, respectively. However, the risk quotient analysis indicated that the risk of dietary intake of thiamethoxam and pyraclostrobin in pickled cowpeas by Chinese consumers was negligible.

The interaction effects of pesticides with Saccharomyces cerevisiae and their fate during wine-making process

Pesticide residues in grapes could be transferred to fermentation system during the wine-making process, which may interfere the normal proliferation of Saccharomyces cerevisiae and subsequently affect the safety and quality of wine products. However, the interaction between pesticides and Saccharomyces cerevisiae is still poorly understood. Herein, the fate, distribution and interaction effect with Saccharomyces cerevisiae of five commonly-used pesticides during the wine-making process were evaluated. The five pesticides exerted varied inhibition on the proliferation of Saccharomyces cerevisiae, and the order of inhibition intensity was difenoconazole > tebuconazole > pyraclostrobin > azoxystrobin > thiamethoxam. Compared with the other three pesticides, triazole fungicides difenoconazole and tebuconazole showed stronger inhibition and played a major role in binary exposure. The mode of action, lipophilicity and exposure concentration were important factors in the inhibition of pesticides. Saccharomyces cerevisiae had no obvious impacts on the degradation of target pesticides in the simulated fermentation experiment. However, the levels of target pesticides and their metabolite were significantly reduced during the wine-making process, with the processing factors ranged from 0.030 to 0.236 (or 0.032 to 0.257) during spontaneous (or inoculated) wine-making process. As a result, these pesticides were significantly enriched in the pomace and lees, and showed a positive correlation (R² ≥ 0.536, n = 12, P < 0.05) between the hydrophobicity of pesticides and distribution coefficients in the solid-liquid distribution system. The findings provide important information for rational selection of pesticides on wine grapes and facilitate more accurate risk assessments of pesticides for grape processing products.

Toxicological effects, residue levels and risks of endocrine-disrupting chemicals in Chinese medicine: a review

Traditional Chinese medicine (TCM) that is used worldwide possesses the satisfactory function of disease prevention, treatment and health care, and this natural medicine seems to be favored due to its low side effects. Endocrine disrupting chemicals (EDCs), which exist in all aspects of our lives, may interfere with the synthesis, action and metabolism of human sex steroid hormones, resulting in the development and fertility problems as well as obesity and the disturbance of energy homeostasis. From planting to processing, TCM may be polluted by various EDCs. Many studies pay attention to this problem, but there are still few reviews on the residues and toxicity risks of EDCs in TCM. In this paper, researches related to EDCs in TCM were screened. The possible contamination sources of TCM from planting to processing and its toxic effects were introduced. Moreover, the residues of metals, pesticides and other EDCs in TCM as well as the health risks of human exposure to EDCs through ingestion of TCM materials were reviewed.

Dietary exposure risk assessment of pyrethroids in fruits and vegetables: a national scale investigation

The pyrethroids (PYRs) were extensively used to increase agriculture outputs. However, the cumulative exposures of PYRs would bring about potential risks through food intake. It is an urgent requirement to explore the cumulative exposures on the fruits and vegetables. In this study, a total of 1720 samples incorporating eight primary fruits and vegetables collected around China were investigated to assess the health risk for adults and children from eight PYRs. The relative potency factor (RPF) method was employed to reveal both chronic and acute cumulative exposure. As a result, the hazard index (HI) were 0.004 ~ 0.200% and 11.85 ~ 99.19% for chronic and acute cumulative dietary exposure, respectively. The national wide investigation indicated the cumulative assessments were not hazardous. Besides, the acute intake of pear, grape, and lettuce should be paid on more attention, particularly. This study provides compelling evidence to develop relative policy and regulation to improve the food quality and safety.

Simultaneous determination of residues of multiple pesticides and their metabolites in citrus and orange juice from markets in China: residue levels and dietary risk assessment

Consumers are becoming more concerned about pesticide residues in food. Since citrus represent a significant portion of the diet, it is appropriate to monitor the pesticide residues in citrus. In this paper, we modified a QuEChERS method combined with HPLC-MS/MS to investigate residue levels of 15 pesticides and 3 metabolites in citrus (whole fruit and pulp) and orange juice from the markets in China. And the dietary exposure risks were evaluated by using the hazard quotient (HQ) and hazard index (HI) methods based on deterministic and probabilistic models. The recoveries of the modified method ranged from 70 to 112% at three spike levels of 0.005-0.5 mg/kg with relative standard deviations of 1.0-18.1%. Pesticide residues were detected in 85.84% of the whole citrus and 40.00% of pulp, with concentrations ranging from 0.005 to 0.47 mg/kg, which did not exceed their maximum residue limits (MRLs) in China. The HQ (0.01-11.41%) and HI (0.07-16.2%) were both less than 100%, demonstrating that chronic, acute, and cumulative dietary risks were acceptable. Notably, the risk for children (1-6 years old, 1.96-16.2%) was higher than that for the general population (0.76-6.25%). The results of our study can provide a valuable reference for regular monitoring to protect public health and ensure pesticide management.

Occurrence of pesticide residues in honey from apiaries with incidents of honeybee poisoning in East China and a corresponding risk assessment for honeybees and Chinese consumers

We investigated the occurrence of 80 pesticide residues in 96 honey samples from apiaries with honeybee poisoning incidences by liquid chromatography-tandem mass spectrometry and subsequently conducted risk assessments of exposure for in-hive honeybees and Chinese consumers. Six pesticides were detected with residue concentrations ranging from 0.5 to 130.9 µg/kg. The mean concentrations of acetamiprid, dinotefuran, hexythiazox, propargite, semiamitraz, and carbendazim in positive samples were 7.9 ± 9.1, 5.9 ± 1.7, 3.0 ± 1.6, 44.2 ± 50.0, 9.0 ± 9.4, and 5.5 ± 4.1 µg/kg, respectively. Carbendazim, semiamitraz, and acetamiprid were the major contaminants in honey, with incidences of 99.0%, 93.8%, and 49.0%, respectively. The cooccurrence of pesticides (≥2 pesticides) was detected in 95.9% of the samples, with up to six residual pesticides found in one sample. The HQ (hazard quotient) values of the six pesticides to in-hive honeybees were from 4.7 × 10^-8 to 0.021, less than 1, indicating their acceptable exposure risk to honeybees. In terms of the representative-case and worst-case scenarios, the sum of separate HQs of each pesticide yielding an HI (hazard index) ranged from 0.012 to 0.016 for in-hive worker honeybees and from 0.015 to 0.021 for in-hive larva honeybees, indicating an overall acceptable potential cumulative risk of multiple pesticides to in-hive honeybees. Both the %ARfD (acute reference dose) value (0.0001-0.075) and %ADI (acceptable daily intake) value (0.00002-0.0046) of risky pesticides were much less than 100, revealing acceptable risk exposure to risky pesticides via honey consumption for human health. Thus, our results showed that multipesticide residual honey from apiaries with honeybee poisoning incidents in East China was safe for humans and in-hive honeybees. PRACTICAL APPLICATION: This analytical approach will be used in detecting multiple pesticide residues in honey and risk assessment for dietary exposure to pesticide residues. It can support various surveillance programs about honey safety and in-hive honeybee health evaluation.

CFD-based pesticide selection for a nozzle used in a six-rotor UAV in hover mode for tea spraying

BACKGROUND

A key challenge for unmanned aerial vehicle (UAV) spraying sometimes used in tea plantations is the downwash flow structure there stronger than in crops. In addition, the UAV spray is affected by the relationship between the nozzle design and the pesticide. However, there is little current research on this aspect. As a preliminary step this study focuses on the most appropriate pesticide for a designated nozzle in a six-rotor UAV according to the nozzle-pesticide relationship using a three-dimensional computational fluid dynamics model. This model considers the downwash flow structure effect and nozzle spray performance in hover. Nozzle FVP110-02, widely used in six-rotor UAVs, is used as a representative nozzle and bifenthrin and tea saponin water, commonly used in tea plantations, are used as the pesticides.

RESULTS

The downwash flow structure of the six-rotor UAV in hover was conveniently controlled by the flight height and rotational speed, thereby causing the turbulence to be more stable. For nozzle FVP110-02, bifenthrin was more appropriate than tea saponin water at the same concentration, whilst bifenthrin and tea saponin water at a concentration of 1:1000 showed the best performance under identical working conditions.

CONCLUSION

The numerical model developed here was shown to be effective for investigating the relationship between nozzle and pesticide. Our findings will help to not only improve UAV spraying for tea cultivation but also provide guidelines for pesticide selection in crops. Further work will address the comparison of the rigorous qualification of the numerical simulations with the measurements by the field test. © 2023 Society of Chemical Industry.

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.

Chromatographic Method for Monitoring of Pesticide Residues and Risk Assessment for Herbal Decoctions Used in Traditional Korean Medicine Clinics

The presence of pesticide residues in herbs and the herbal products derived from them raises serious health concerns. This study was conducted to investigate the residual pesticide concentrations and assess potential human health risks from herbal medicines used in traditional Korean medicine clinics. A total of 40 samples of herbal decoctions were collected from 10 external herbal dispensaries. The pesticide residues were analyzed by the multiresidue method for 320 different pesticides using liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography tandem mass spectrometry (GC-MS/MS). As a result of the monitoring, carbendazim was detected at 0.01 and 0.03 μg/g in eight samples and no pesticide was detected in the other herbal decoctions. Carbendazim was set for each individual item as less than 0.05 μg/g in Paeoniae radix, less than 0.05 μg/g in Cassiae semen, less than 2.0 μg/g in Lycii fructus, and less than 10 μg/g in Schisandrae fructus (dried). Therefore, the results of this study suggested that the detected pesticide residues in herbal decoctions could not be considered as posing a serious health risk.

Enrichment and health risks associated with trace elements in medicine food homology teas

Owing to the irreplaceable role of traditional Chinese medicine in the history of human resistance to diseases, medicine food homology teas (MFHTs) have emerged as a widely-consumed daily drink, although they may contain toxic or excessive trace elements. This study aims to determine the total and infused concentrations of nine trace elements (Fe, Mn, Zn, Cd, Cr, Cu, As, Pb, and Ni) in 12 MFHTs collected from 18 provinces in China, to evaluate their potential risks to human health, and to explore the factors affecting the trace element enrichment in traditional MFHTs. The exceedances of Cr (82%) and Ni (100%) in 12 MFHTs were higher than those of Cu (32%), Cd (23%), Pb (12%), and As (10%). The high values of the Nemerow integrated pollution index of dandelions and Flos sophorae (25.96 and 9.06, respectively) indicate severe trace metal pollution. The health risk assessment results showed that As, Cr, and Mn in the 12 types of MFHTs posed high non-carcinogenic risk. Honeysuckle and dandelion teas may be hazardous to human health through trace element exposure when consumed daily. The enrichment of Cr, Fe, Ni, Cu, Zn, Mn, and Pb in MFHTs is influenced by the MFHT type and producing area, whereas As and Cd are mainly controlled by the MFHT type. Environmental factors such as soil background values, rainfall, and temperature also affect the enrichment of trace elements in MFHTs collected from different producing areas.

Migration behavior and dietary exposure risk assessment of pesticides residues in honeysuckle (Lonicera japonica Thunb.) based on modified QuEChERS method coupled with tandem mass spectrometry

The honeysuckle was widely appreciated as tea beverage owing to the biological activities and the unique aroma and flavor. It is in urgent requirement to explore the migration behavior and dietary exposure as the pesticide residues would bring about potential risks through honeysuckle intake. The optimized QuEChERS procedure coupled with the HPLC-MS/MS and GC-MS/MS methods were employed to determine 93 pesticide residues of seven classifications including carbamates, pyrethroid, triazoles, neonicotinoids, organophosphorus, organochlorine, and others for 93 honeysuckle samples from four primary production bases. As a result, 86.02% of the samples were contaminated by at least one pesticide. Unexpectedly, the banned pesticide of carbofuran was also identified. The migration behavior of metolcarb was the highest, whereas thiabendazole contributed less risk to the infusion with relative lower transfer rate. Both the chronic and acute exposure yielded low risk for human health with five high risk pesticides of dichlorvos, cyhalothrin, carbofuran, ethomyl, and pyridaben. Besides, this study provides foundation of dietary exposure risk assessment for honeysuckle and other likewise products.

Advances of non-thermal plasma discharge technology in degrading recalcitrant wastewater pollutants. A comprehensive review

With development and urbanization, the amount of wastewater generated due to human activities drastically increases yearly, causing water pollution and intensifying the already worsened water crisis. Although convenient, conventional wastewater treatment methods such as activated sludge, stabilization ponds, and adsorption techniques cannot fully eradicate the complex and recalcitrant contaminants leading to toxic byproducts generation. Recent advancements in wastewater treatment techniques, specifically non-thermal plasma technology, have been extensively investigated for the degradation of complex pollutants in wastewater. Non-thermal plasma is an effective alternative for degrading and augmenting the biodegradability of recalcitrant pollutants due to its ability to generate reactive species in situ. This article critically reviews the non-thermal plasma technology, considering the plasma discharge configuration and reactor types. Furthermore, the influence of operational parameters on the efficiency of the plasma systems and the reactive species generated by the system during discharge has gained significant interest and hence been discussed. Also, the application of non-thermal plasma technology for the degradation of pharmaceuticals, pesticides, and dyes and the inactivation of microbial activities are outlined in this review article. Additionally, optimistic applications involving the combination of non-thermal plasma and catalysts and pilot and industrial-scale projects utilizing non-thermal plasma technology have been addressed. Concluding perceptions on the challenges and future perspectives of the non-thermal technology on wastewater treatment are accentuated. Overall, this review outlines a comprehensive understanding of the non-thermal plasma technology for recalcitrant pollutant degradation from a scientific perspective providing detailed instances for reference.

Quantification of insecticides in commercial seafood sold in East Asian markets: risk assessment for consumers

The extraction of 21 insecticides and 5 metabolites was performed using an optimized and validated QuEChERS protocol that was further used for the quantification (GC-MS/MS) in several seafood matrices (crustaceans, bivalves, and fish-mudskippers). Seven species, acquired from Hong Kong and Macao wet markets (a region so far poorly monitored), were selected based on their commercial importance in the Indo-Pacific region, market abundance, and affordable price. Among them, mussels from Hong Kong, together with mudskippers from Macao, presented the highest insecticide concentrations (median values of 30.33 and 23.90 ng/g WW, respectively). Residual levels of fenobucarb, DDTs, HCHs, and heptachlors were above the established threshold (10 ng/g WW) for human consumption according to the European and Chinese legislations: for example, in fish-mudskippers, DDTs, fenobucarb, and heptachlors (5-, 20- and tenfold, respectively), and in bivalves, HCHs (fourfold) had higher levels than the threshold. Risk assessment revealed potential human health effects (e.g., neurotoxicity), especially through fish and bivalve consumption (non-carcinogenic risk; ΣHQ_LT > 1), and a potential concern of lifetime cancer risk development through the consumption of fish, bivalves, and crustaceans collected from these markets (carcinogenic risk; ΣTCR > 10^-4). Since these results indicate polluted regions, where the seafood is collected/produced, a strict monitoring framework should be implemented in those areas to improve food quality and safety of seafood products.

Biochar Derived from Chinese Herb Medicine Residues for Rhodamine B Dye Adsorption

In this study, one well-known CHM residue (Atropa belladonna L., ABL) was used to prepare biochar capable of adsorbing rhodamine B (RhB) with an ultrahigh surface area for the first time. Three micropore-rich ABL biochars including ABL@ZnCl₂ (1866 m²/g), ABL@H₃PO₄ (1488 m²/g), and ABL@KOH (590 m²/g) were obtained using the one-step carbonization method with activation agents (ZnCl₂, H₃PO₄, and KOH) via chemical activation and carbonization at 500 °C, and their adsorption performance for RhB was systematically studied with adsorption kinetics, isotherms, and thermodynamics. Through pore diffusion, π-π interaction, and hydrogen bonding, ABL biochar had excellent adsorption performance for RhB. Moreover, when C ₀ was 200 mg/L, biochar dosage was 1 g/L, and the contact time was 120 min; the maximum RhB adsorption capacity and removal efficiency on ABL@ZnCl₂ and ABL@H₃PO₄ were 190.63 mg/g, 95% and 184.70 mg/g, 92%, respectively, indicating that it was feasible to prepare biochar from the ABL residue for RhB adsorption. The theoretical maximum adsorption capacities of ABL@ZnCl₂ and ABL@H₃PO₄ for RhB were 263.19 mg/g and 309.11 mg/g at 25 °C, respectively. Furthermore, the prepared biochar showed good economic applicability, with pay back of USD 972/t (ABL@ZnCl₂) and USD 987/t (ABL@H₃PO₄), respectively. More importantly, even after five cycles, ABL@H₃PO₄ biochar still showed great RhB removal efficiency, suggesting that it had a good application prospect and provided a new method for the resource utilization of traditional CHM residues. Additionally, pore diffusion, π-π interactions, and hydrogen bonding all play roles in the physical adsorption of RhB on ABL biochar. π-π interactions dominated in the early stage of RhB adsorption on ABL@H₃PO₄, while pore diffusion played a crucial role in the whole adsorption process on both adsorbents.

Assessment of health risks associated with pesticide and heavy metal contents in Fritillaria thunbergii Miq. (Zhe Beimu)

Fritillaria thunbergii Miq. (Zhe Beimu, F. thunbergii) is widely cultivated in China's Zhejiang province, and pesticides and heavy metals are two major factors affecting its quality and safety. A total of 106 F. thunbergii samples from six main production areas were analyzed for 76 pesticides and four heavy metal content (As, Cd, Hg, and Pb). The pesticide detection rate of the samples was 66.98%; overall, the pesticide residues were very low, and residue levels ranged from 0.010 to 0.231 mg kg^-1. The detection rates of As, Cd, Hg, and Pb were 95.3%, 100%, 76.4%, and 100%, respectively. A risk assessment of human exposure to pesticides and heavy metals via intake of F. thunbergii was performed, and the results revealed that the pesticide residues and heavy metal content detected in F. thunbergii does not pose a potential risk to human health, either in the long or short term. The exposure assessment showed that the levels of pesticides and heavy metals in F. thunbergii were safe for human consumption. These results provide useful information on F. thunbergii consumption.

The sulfoximine insecticide sulfoxaflor exposure reduces the survival status and disrupts the intestinal metabolism of the honeybee Apis mellifera

Honeybees (Apis mellifera) are indispensable pollinators in agricultural production, biodiversity conservation, and nutrients provision. The abundance and diversity of honeybees have been rapidly diminishing, possibly related to the extensive use of insecticides in ecosystems. Sulfoxaflor is a novel sulfoximine insecticide that, like neonicotinoids, acts as a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects. However, few studies have addressed the negative effects of sulfoxaflor on honeybees at environmentally relevant concentrations. In the present study, adult workers were fed a 50% (w/v) of sugar solution containing different concentrations (0, 0.05, 0.5 and 2.0 mg/L) of sulfoxaflor for two weeks consecutively. The survival rates, food intake, and body weight of the honeybees significantly decreased after continuous exposure at higher doses (0.5 and 2.0 mg/L) of sulfoxaflor when compared with the control. The change in the metabolites in the honeybee gut was determined using high-throughput non-targeted metabolomics on day 14 after sulfoxaflor treatment. The results revealed that 24 and 105 metabolites changed after exposure to 0.5 and 2.0 mg/L sulfoxaflor, respectively, compared with that of the control groups. A total of 12 changed compounds including pregenolone and glutathione were detected as potential biomarkers, which were eventually found to be enriched in pathways of the steroid hormone biosynthesis (p = 0.0001) and glutathione metabolism (p = 0.021). These findings provide a new perspective on the physiological influence of sulfoxaflor stress in honeybees.

MRTCM: A comprehensive dataset for probabilistic risk assessment of metals and metalloids in traditional Chinese medicine

Traditional Chinese medicine (TCM) is still considered a global complementary or alternative medical system, but exogenous hazardous contaminants remain in TCM even after decocting. Besides, it is time-consuming to conduct a risk assessment of trace elements in TCMs with a non-automatic approach due to the wide variety of TCMs. Here, we present MRTCM, a cloud-computing infrastructure for automating the probabilistic risk assessment of metals and metalloids in TCM. MRTCM includes a consumption database and a pollutant database involving forty million rows of consumption data and fourteen types of TCM potentially toxic elements concentrations. The algorithm of probabilistic risk assessment was also packaged in MRTCM to assess the risks of eight elements with Monte Carlo simulation. The results demonstrated that 96.64% and 99.46% had no non-carcinogenic risk (hazard indices (HI) were < 1.0) for animal and herbal medicines consumers, respectively. After twenty years of exposure, less than 1% of the total carcinogenic risk (CR_t) was > 10^-4 for TCM consumers, indicating that they are at potential risk for carcinogenicity. Sensitivity analysis revealed that annual consumption and concentration were the main variables affecting the assessment results. Ultimately, a priority management list of TCMs was also generated, indicating that more attention should be paid to the non-carcinogenic risks of As, Mn, and Hg and the carcinogenic risks of As and Cr in Pheretima and Cr in Arcae Conch. In general, MRTCM could significantly enhance the efficiency of risk assessment in TCM and provide reasonable guidance for policymakers to optimize risk management.

The safety of Chinese medicine: A systematic review of endogenous substances and exogenous residues

BACKGROUND

Safety and toxicity have become major challenges in the internationalization of Chinese medicine. Inspite of its wide application, security problems of Chinese medicine still occur from time to time, raising widespread concerns about its safety. Most of the studies either only partially discussed the intrinsic toxicities or extrinsic harmful residues in Chinese medicine, or briefly described detoxification and attenuation methods. It is necessary to systematically discuss Chinese medicine's extrinsic and intrinsic toxic components and corresponding toxicity detoxification or detection methods as a whole.

PURPOSE

This review comprehensively summarizes various toxic components in Chinese medicine from intrinsic and extrinsic. Then the corresponding methods for detoxification or detection of toxicity are highlighted. It is expected to provide a reference for safeguards for developing and using Chinese medicine.

METHODS

A literature search was conducted in the databases, including PubMed, Web of Science,Wan-fang database, and the China National Knowledge Infrastructure (CNKI). Keywords used were safety, toxicity, intrinsic toxicities, extrinsic harmful residues, alkaloids, terpene and macrolides, saponins, toxic proteins, toxic crystals, minerals, heavy metals, pesticides, mycotoxins, sulfur dioxide, detoxification, detection, processing (Paozhi), compatibility (Peiwu), Chinese medicine, etc., and combinations of these keywords. All selected articles were from 2006 to 2022, and each was assessed critically for our exclusion criteria. Studies describe the classification of toxic components of Chinese medicine, the toxic effects and mechanisms of Chinese medicine, and the corresponding methods for detoxification or detection of toxicity.

RESULTS

The toxic components of Chinese medicines can be classified as intrinsic toxicities and extrinsic harmful residues. Firstly, we summarized the intrinsic toxicities of Chinese medicine, the adverse effects and toxicity mechanisms caused by these components. Next, we focused on the detoxification or attenuation methods for intrinsic toxicities of Chinese medicine. The other main part discussed the latest progress in analytical strategies for exogenous hazardous substances, including heavy metals, pesticides, and mycotoxins. Beyond reviewing mainstream instrumental methods, we also introduced the emerging biochip, biosensor and immuno-based techniques.

CONCLUSION

In this review, we provide an overall assessment of the recent progress in endogenous toxins and exogenous hazardous substances concerning Chinese medicine, which is expected to render deeper insights into the safety of Chinese medicine.

Occurrence, distribution, and driving factors of current-use pesticides in commonly cultivated crops and their potential risks to non-target organisms: A case study in Hainan, China

Multiple pesticides are heavily applied in crops grown in China's tropics due to the prevalence of diseases and pests, thus posing potential risks to nontarget organisms (e.g., honeybees, lacewings, ladybugs, and humans). However, there is little information on this topic. This study is the first assessment of the occurrence, driving factors, and ecological/human health risks of 32 current-use pesticides (CUPs) in 10 frequently-planted crops collected from practicing rice-vegetable rotation systems in Hainan, China. Of the 132 whole crop samples, 44 (33.3 %) residues from ≥8 pesticides were detected in 9.09 % of crop samples with concentrations ≥0.5 mg kg-1. Six pesticide residues, namely carbendazim, pyraclostrobin, acetamiprid, thiophanate methyl, phoxim, and imidacloprid, were detected in 72.7 % of samples, with concentrations ranging from 0.0021 to 13.5 (median = 0.032) mg kg-1. Among them, carbendazim, pyraclostrobin, and acetamiprid were the most common, contributions from 10.2 to 25.5 % and a detection frequency ranging from 25.6 to 56.1 %. The order of total concentration of 32 CUPs (∑32 CUP) concentrations during the year was January > May > November > August and vegetables > rice, being highly related with pesticides usage pattern, crop type, plant accumulation/dissipation and plant lipid contents. The ecological risk quotients (RQs) to four beneficial terrestrial organisms showed that 9.6-39.1 % of samples posed a potential medium or high ecological risk, with 13.6-65.9 % of samples at ∑RQ > 1 being highly affected by the residues of neonicotinoids and emamectin benzoate. Emamectin benzoate (8.9 %) and acetamiprid (5.6 %) exceeded the individual Maximum Residue Levels based on Chinese legislation (GB2763-2021). Moreover, cumulative dietary exposure presented a higher risk to humans in 11.0 and 22.0 % of the cases for acute and chronic, mainly originating from the higher concentration contributors of systemic pesticides in edible crops. Therefore, the regulation and monitoring of CUP residues is imperative for rice-vegetable rotation systems in tropical China to avoid negative effects on nontarget organisms.

Residual levels and dietary exposure risk assessment of banned pesticides in fruits and vegetables from Chinese market based on long-term nontargeted screening by HPLC-Q-TOF/MS

The negative impact of banned pesticides is of special importance for their high toxicity. In this study, nationwide screening of banned pesticides in 37462 fruit and vegetable samples was carried out from 2012 to 2018 using a self-developed HPLC-Q-TOF/MS technique. The dietary exposure risks associated with the banned pesticides were assessed. The results showed that 66.62 % of the samples were detected at least one pesticide. Among the pesticide-positive samples, a total of 18 banned pesticides were detected in 1798 samples for 1896 times. The risk assessment revealed that 11.71 % of the positive detections exceeded the safety limits and posed an unacceptable risk, while 37.29 % of the positive detections posed acceptable risks. According to the screening and assessment results, two national maps were presented to show the total detection ratios of the banned pesticides and the unacceptable risks of dietary exposure. It should be noted that omethoate had higher residual concentration, unacceptable risk frequency and unacceptable risk proportion. This is the first nationwide comprehensive report on screening and risk assessment banned pesticides.

A fluorescent aptasensor based on gold nanoparticles quenching the fluorescence of rhodamine B to detect acetamiprid

Pesticide residue detection is one of the main safety issues in the utilization of medicinal plants. In this work, a highly selective and sensitive aptasensor for acetamiprid determination was designed. The mechanism of the proposed method is based on the fluorescence resonance energy transfer (FRET) between gold nanoparticles (AuNPs) and rhodamine B (RB). Aptamers protect AuNPs from salt-induced aggregation, which causes fluorescence quenching of RB by the AuNPs via surface energy transfer. In the absence of acetamiprid, AuNPs were coated with aptamers on the surface and dispersed in NaCl solution. At this time, the dispersed AuNPs could perfectly quench the fluorescence intensity of RB. In contrast, in the presence of acetamiprid, aptamers specifically combine with acetamiprid to form a complex. With a high salt concentration, AuNPs would be aggregated without aptamer protection, weakening the RB quenching effect. Therefore, the concentration of acetamiprid could be obtained from the change in fluorescence intensity in the system. A fluorescent sensing method was established with a linear range from 0.1 to 3 μg mL^-1, and the LOD was 0.0285 μg mL^-1. The recoveries of acetamiprid in traditional Chinese medicine (TCM) samples were 96.23-105.75%. This method has great application value for the detection of acetamiprid in a complex sample matrix.

Medicinal herbs and multiple sclerosis: Overview on the hard balance between new therapeutic strategy and occupational health risk

Multiple sclerosis (MS) is an autoimmune disease characterized by demyelination and axonal loss of the central nervous system (CNS). Despite its spread throughout the world, the mechanisms that determine its onset are still to be defined. Immunological, genetic, viral, and environmental factors and exposure to chemicals may trigger MS. Many studies have highlighted the anti-inflammatory and anti-oxidant effects of medicinal herbs, which make them a natural and complementary treatment for neurodegenerative diseases. A severe reduction of several MS symptoms occurs with herbal therapy. Thus, the request for medicinal plants with potential beneficial effects, for MS patients, is constantly increasing. Consequently, a production increase needs. Unfortunately, many medicinal herbs were untested and their action mechanism, possible adverse effects, contraindications, or interactions with other drugs, are poorly or not investigated. Keeping in mind the pathological mechanisms of MS and the oxidative damages and mitochondrial dysfunctions induced by pesticides, it is important to understand if pesticides used to increase agricultural productivity and their residues in medicinal plants, may increase the risk of developing MS in both workers and consumers. Studies providing some indication about the relationship between environmental exposure to pesticides and MS disease incidence are few, fragmentary, and discordant. The aim of this article is to provide a glance at the therapeutic potential of medicinal plants and at the risk for MS onset of pesticides used by medicinal plant growers and present in medicinal herbs.

Dietary exposure and risk assessment of chlorinated paraffins in roots and rhizomes of traditional Chinese medicine herbs

Traditional Chinese medicine (TCM) provides therapeutic and health care effects through dietary intake. Owing to the susceptibility of plants to contaminations, a risk assessment system is urgently needed to ensure the safe use of TCMs. In this study, the contamination levels and risks associated with the dietary intake of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were investigated in six kinds of frequently-used TCM herbs. The concentrations varied from 144.4 to 1527.8 ng·g-1 dw for SCCPs and non-detect to 1214.1 ng·g-1 dw for MCCPs, with mean values of 551.5 and 259.8 ng·g-1 dw, respectively. A geographic distribution analysis indicated that the concentrations of CPs in TCMs were mainly associated with their levels of contamination in the ambient environment. Carbon atom-chlorine congener profiles of CPs were dominated by C10Cl7-8 and C14Cl7-8 congeners, accounting for 20.1% and 32.4% of the total SCCP and MCCP concentrations, respectively. Principal component analysis indicated that the TCM species might be the main factor influencing the accumulation of SCCPs congeners. Finally, a risk assessment reveals that the estimated daily intake and margin of exposure were far below levels that might pose a health risk, indicating an acceptable dietary intake of SCCPs and MCCPs in the studied TCMs. This is the first report of CPs in the TCM herbs and the obtained results are expected to aid in future evaluation of the quality of TCMs and ensuring diet and drug safety.

Residue and distribution of drip irrigation and spray application of two diamide pesticides in corn and dietary risk assessment for different consumer groups

BACKGROUND

As the use of diamide insecticides on corn continues to increase, there is growing concern about their residue levels on corn and dietary risks to populations. In this study, the distribution, dispersion and transfer efficiency of two diamide insecticides (tetrachlorantraniliprole (TCAP) and cyantraniliprole (CNAP)) in different parts of corn and soil were investigated in a 1-year field trial in Guangzhou and Lanzhou using two different application methods - spray and drip irrigation, respectively - and the dietary risk of the insecticides to different consumer populations was assessed under the two application methods.

RESULTS

The results showed that drip irrigation had a longer persistence period than spraying, and there was a hysteresis in the absorption distribution of the agent in different parts of corn, which was gradually transferred to the leaves after absorption from the roots. The average TE₁ (transfer efficiency) and TE₂ were 0.230-0.261 and 1.749-1.851 for TCAP and 0.168-0.187 and 2.363-2.815 for CNAP, respectively. At corn harvest, both TCAP and CNAP were below detectable levels in soil and corn. For different consumer populations, hazard quotients ranged from 0.001 to 0.066 for TCAP and from 0.003 to 0.568 for CNAP - both well below 100%.

CONCLUSION

This study indicates that TCAP and CNAP applied by spray or drip irrigation are safe for long-term risk of human intake and also provides guidance for the use of both insecticides in agricultural production to control corn pests, especially in arid and semi-arid areas. © 2022 Society of Chemical Industry.

Toxic effects of detected pyrethroid pesticides on honeybee (Apis mellifera ligustica Spin and Apis cerana cerana Fabricius)

To obtain the presence of environmental contaminants in honeybee and compare the toxicity of the detected pesticides to Apis mellifera ligustica Spin and Apis cerana cerana Fabricius. In this work, 214 honeybee samples were collected to simultaneous monitoring 66 pesticides between 2016 and 2017 in China. A modified QuEChERS extraction method coupled with multi-residue analytical methods by Ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and Gas chromatography-mass spectrum (GC–MS). Among, four pyrethroid pesticides were selected to test and compare the acute oral toxicities of two honeybees. And the survival risk of beta-cypermethrin was analyzed to them. Using this method, 21 compounds were detected, including 3 neonicotinoids, 5 pyrethroids, 5 organophosphorus and 8 others. Importantly, detected frequencies of pyrethroid pesticides were accounted for 53.3%. Among, acute toxicity values (LD₅₀) of four pyrethroid pesticides to the A.m. ligustica were higher than of that the A.c. cerana. When they were exposed to the same concentration of beta-cypermethrin (0.2906 mg/L), the survival rate of the A.m. ligustica (40.0%) was higher than the A.c. cerana (18.9%). Our work is valuable to analyze multiple pesticide residues of honeybees and evaluate the survival risk of two honeybee species, which also provides a basis for the risk assessment.

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.

Rapid screening of imidacloprid residue in grains and medicinal herbs: A newly designed hapten and monoclonal antibody

Three different imidacloprid hapten structures were designed to conjugate with proteins (bovine serum albumin, BSA; ovalbumin, OVA; keyhole limpet hemocyanin, KLH) for screening the optimal immunogen and coating antigen. Among these, an unreported antigen (hapten 6-KLH) was selected as the optimal immunogen and coating antigen. In addition, an imidacloprid-specific and high titer monoclonal antibody (IMIB7C3) was obtained by using the above-selected immunogen. A sensitive ic-ELISA (indirect competitive enzyme-linked immunosorbent assay) with a half-maximal inhibitory concentration (IC₅₀) of 1.3 ng mL^-1 was established by using the IMIB7C3 antibody (only 1.2 ng per well) to detect the residues of imidacloprid in grains (wheat and maize) and different herbs (Notoginseng radix et rhizoma, Dioscoreae rhizoma, Lonicerae japonicae flos, Astragali radix, Jujubae fructus). The detection results of real samples by the developed immunoassay were confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), which proved the accuracy and reliability of the established ic-ELISA. These results indicate that the proposed ic-ELISA method is suitable for rapid and high-throughput detection of imidacloprid residues in agricultural products and medicinal herbs. Furthermore, a quantitative risk assessment was conducted for Lonicerae japonicae flos based on the detection results, which indicates an acceptable risk to human health after the intake of Lonicerae japonicae flos polluted by imidacloprid.

A mechanistic approach for toxicity and risk assessment of heavy metals, hydroquinone and microorganisms in cosmetic creams

The demand and importance of fairness creams as a major cosmetic have increased significantly in recent years. However, some of these cosmetics contain heavy metals, hydroquinone and microorganism that can cause various health problems. Therefore, the aim of this study is to determine and examine the concentration of metals (i.e. Cd, Pb, Cr, Ni, Zn, Hg), hydroquinone and microorganisms in nine different fairness creams produced by local and international brands. The health risk assessment of the tested substances for consumers was accessed through systemic exposure dosage (SED), margin of safety (MoS), lifetime cancer risk (LCR), hazard quotient (HQ) and hazard index (HI). The concentration of Zn and Hg were found the highest and measured in the range of 17.82-138.06 mg.kg^-1 and 2.3-141 mg.kg^-1, respectively. The concentrations of other metals were determined as 0.06-0.67 mg.kg^-1 of Cd, 0.43-1.55 mg.kg^-1 of Cr, 0.14-1.43 mg.kg^-1 of Ni and 0.3-1.34 mg.kg^-1 of Pb. HPLC results showed a significant presence of hydroquinone in the range of 0.12-7.2%. The total viable counts of cosmetic samples showed the substantial presence of microorganisms, and 44% of the collected samples surpassed the permissible limit of 100 cfu/g recommended by European Union. Many of the collected samples exceeded the MoS, HQ and HI tolerance limits. However, the LCR value in all samples was significantly higher than the acceptable limit. Therefore, it is advised to avoid overuse of these products in order to ensure human safety and reduce the risks to skin health.

Dissipation and dietary exposure risk assessment of pyraclostrobin, fluxapyroxad, difenoconazole, and azoxystrobin in the Fritillaria field ecosystem

Fritillaria (Beimu in Chinese) is a well-known traditional Chinese medicinal herbal and valuable health food, which has attracted more and more attention. In this study, an efficient method was developed to determine pyraclostrobin, fluxapyroxad, difenoconazole, and azoxystrobin in plants, fresh Fritillaria, dry Fritillaria, and soil via liquid chromatography-tandem mass spectrometry. The average recoveries of the method were 78.9-109.7% with relative standard deviations of 0.94-11.1%. The dissipation half-lives of the four fungicides were 4.4-7.7 days in the Fritillaria plant and 11.6-18.2 days in the soil. The terminal residues of four fungicides were 0.033-0.13 mg/kg in fresh Fritillaria, 0.096-0.42 mg/kg in dry Fritillaria, and 0.12-0.74 mg/kg in soil. In the risk assessment of dietary exposure, all the chronic hazard quotient and acute hazard quotient index values were far below 100%, which were both acceptable to consumers. Accordingly, 7 days was recommended as the pre-harvest interval for the four fungicides in Fritillaria. This work could guide the safe use of these fungicides in Fritillaria and also give a reference for the Chinese government to establish the maximum residue limits (MRLs).

Dissipative behavior, residual pattern, and risk assessment of four pesticides and their metabolites during tea cultivation, processing and infusion

BACKGROUND

In recent years, metabolic products of pesticides have gained much attention due to their substantial characteristics as organic pollutants. So far, the behavior and metabolite levels of pesticide metabolites in crops have not been characterized well. In the present study, four registered pesticides (imidacloprid, diafenthiuron, malathion and chlorothalonil) were applied on tea plants in Fujian and Sichuan to characterize their metabolites residue pattern and dietary risk.

RESULTS

Four pesticides dissipated first-order kinetics in the fresh tea leaves with the half-lives of 1.4-3.8 days. Nine metabolites were detected in the fresh tea leaves and green tea after processing. The metabolites residues showed an increasing trend first and then declined after treatment, and reached the maximum near the half-lives of pesticide. Compared with the parent pesticide, the total residue and acute risk (included the metabolites) increased by 1.7-105.2 times. Some metabolites, especially those whose parent pesticides have high water solubility and low Log Kow, will be more easily transferred to tea infusion.

CONCLUSION

Pesticides were metabolized rapidly on tea plants after application, but the production of metabolites increased the health risk of tea consumption. These results could provide insights to use the pesticides in tea gardens and risk monitoring after application. © 2022 Society of Chemical Industry.

The dissipation, processing factors, metabolites, and risk assessment of pesticides in honeysuckle from field to table

Globally, honeysuckle is consumed as a food and administered as a medicinal agent. However, pesticide residues in honeysuckle limit its application and development of the honeysuckle industry, affecting food safety and endangering human health. Here, the degradation kinetics of 11 typical pesticides, including insecticides, fungicides, and an acaricide, in honeysuckle were investigated. The half-lives of pesticides in Henan and Liaoning fields were 1.90-4.33 and 2.05-4.62 d, respectively. The processing factors (PFs) of these pesticides after oven, sun, and shade drying ranged from 3.52 to 11.2. After decocting, the PFs of the pesticides were <1. Twenty degradation products were identified using ultra high performance liquid chromatography-quadrupole time-of-flight mass spectrometry, and pathways were proposed based on drying and decoction. The ecotoxicities of the degradation products were evaluated using the Toxicity Estimation Software Tool. Finally, the acute hazard indices of these pesticides, as determined via dietary exposure assessment combined with the PFs, were 0.227 and 0.911 for adults and children, respectively. Thus, special populations, such as children, require particularly careful risk control in terms of dietary exposure.

Monitoring and dietary exposure assessment of pesticide residues in strawberry in Beijing, China

In this study, 142 pesticide residues in 245 strawberry samples, gathered from farmers markets or supermarkets in Beijing from June 2017 to May 2018, were investigated. The samples were analysed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). According to the validation data, including linearity, recovery, precision and measurement uncertainty, the method performed well in monitoring pesticide residues and complied with the requirements of the European Guideline SANTE/11813/2017. Among the strawberry samples, 26.0% contained at least one pesticide residue, four of which contained pesticide residues that exceeded the maximum residue limit of China. Carbendazim, pyrimethanil and azoxystrobin were the most frequently detected pesticides in the strawberry samples. Lower bound, middle bound and upper bound values were used to replace left-censored results. In the worst-case scenario, the hazard index (HI) for adults and children was 0.91% and 3.62%, respectively. Carbofuran, bifenazate and pyraclostrobin were identified as the top three contributors to HI.

Exposure of Larvae to Sublethal Thiacloprid Delays Bee Development and Affects Transcriptional Responses of Newly Emerged Honey Bees

Understanding the cause of honey bee (Apis mellifera) population decline has attracted immense attention worldwide in recent years. Exposure to neonicotinoid pesticides is considered one of the most probable factors due to the physiological and behavioral damage they cause to honey bees. However, the influence of thiacloprid, a relatively less toxic cyanogen-substituted form of neonicotinoid, on honey bee (Apis mellifera L.) development is not well studied. The toxicity of sublethal thiacloprid to larvae, pupae, and emerging honey bees was assessed under laboratory conditions. We found that thiacloprid reduced the survival rate of larvae and pupae, and delayed the development of bees which led to lower bodyweight and size. Furthermore, we identified differentially expressed genes involved in metabolism and immunity though RNA-sequencing of newly-emerged adult bees. GO enrichment analysis identified genes involved in metabolism, catalytic activity, and transporter activity. KEGG pathway analysis indicated that thiacloprid induced up-regulation of genes related to glutathione metabolism and Toll-like receptor signaling pathway. Overall, our results suggest that chronic sublethal thiacloprid can affect honey bee colonies by reducing survival and delaying bee development.

Levels and Health Risk of Pesticide Residues in Chinese Herbal Medicines

In the present study, 168 pesticides in 1,017 samples of 10 Chinese herbal medicines (CHMs) were simultaneously determined by high-performance liquid (HPLC-MS/MS) and gas (GC-MS/MS) chromatography–tandem mass spectrometry. A total of 89.2% of the samples encompassed one or multiple pesticide residues, and the residue concentrations in 60.5% of samples were less than 0.02 mg kg⁻¹, revealing the relatively low residue levels. The hazard quotient and hazard index methods were used to estimate the health risk for consumers. For a more accurate risk assessment, the exposure frequency and exposure duration of CHMs were involved into the exposure assessment, which was obtained from a questionnaire data of 20,917 volunteers. The results of chronic, acute, and cumulative risk assessment indicated that consumption of CHMs is unlikely to pose a health risk to consumers. Ranking the risk of detected pesticides revealed that phorate, BHC, triazophos, methidathion, terbufos, and omethoate posed the highest risk. Our results also showed that pollution of the aboveground medicinal part was more serious. Although exposure to pesticides in tested CHMs was below dangerous levels, more strict controlled management should be carried out for banned pesticides due to the high detection rate and illegal use in the actual planting practice.

Ultrasensitive electrochemiluminescence sensor based on perovskite quantum dots coated with molecularly imprinted polymer for prometryn determination

A highly effective molecularly imprinted electrochemiluminescence sensor was constructed for prometryn determination in environmental and biological samples by using perovskite quantum dots coated with a molecularly imprinted silica layer (MIP/CsPbBr₃-QDs) as the recognition and response element. MIP/CsPbBr₃-QDs were immobilized on a glassy carbon electrode (GCE) through electropolymerization, and the electrochemiluminescence (ECL) response of MIP/CsPbBr₃-QDs could be motivated under the condition of H₂O₂ as co-reactant. ECL signal was selectively quenched with prometryn by hindering electron transfer and directly proportional to the logarithm of prometryn concentration (0.10-500.0 μg/L) with a correlation coefficient of 0.9960. Limits of detection in fish and seawater samples were 0.010 μg/kg and 0.050 μg/L, respectively. Excellent recoveries of 88.0%-106.0% were acquired for fish and seawater samples with a relative standard deviation below 4.2%. The constructed MIECL sensor based on MIP/CsPbBr₃-QDs showed good stability, accuracy, and precision for sensitive detection of prometryn in aquaculture products and environmental samples.

Detection and Risk Assessments of Multi-Pesticides in Traditional Chinese Medicine Chuanxiong Rhizoma by LC/MS-MS and GC/MS-MS

With the internationalization of traditional Chinese medicines (TCMs) and the increasing use of herbal medicines around the world, there are concerns over their safety. In recent years, there have been some sporadic reports of pesticide residues in Chuanxiong Rhizoma (CX), although the lack of systematic and comprehensive analyses of pesticide residues and evaluations of toxicological risks in human health has increased the uncertainty of the potential effects of pesticides exposure in humans. This study aimed to clarify the status of pesticide residues and to determine the health risks of pesticide residues in CX. The findings of this study revealed that 99 batches of CX samples contained pesticide residues ranging from 0.05 to 3013.17 μg/kg. Here, 6–22 kinds of pesticides were detected in each sample. Prometryn, carbendazim, dimethomorph, chlorpyrifos, chlorantraniliprole, pyraclostrobin, and paclobutrazol were the most frequently detected pesticides, with detection rates of 68.69–100%. Insecticides and fungicides accounted for 43.23% and 37.84% of the total pesticides detected, respectively. Here, 86.87% of the pesticide content levels were lower than 50 μg/kg, and a small number of samples contained carbofuran, dimethoate, and isofenphos-methyl exceeding the maximum residue levels (MRLs). A risk assessment based on the hazard quotient/hazard index (HQ/HI) approach revealed that the short-term, long-term, and cumulative risks of pesticide residues in CX are well below the levels that may pose a health risk. Worryingly, six banned pesticides (carbofuran, phorate sulfone, phorate-sulfoxide, isofenphos-methyl, terbufos-sulfone, and terbufoxon sulfoxide) were detected. This study has improved our understanding of the potential exposure risk of pesticide multi-residues in CX. The results of the study will have a positive impact on improving the quality and safety of CX and the development of MRLs for pesticide residues.

Regioselective hydroxylation of carbendazim by mammalian cytochrome P450: A combined experimental and computational study

Carbendazim (CBZ), a broad-spectrum pesticide frequently detected in fruits and vegetables, could trigger potential toxic risks to mammals. To facilitate the assessment of health risks, this study aimed to characterize the cytochrome P450 (CYPs)-mediated metabolism profiles of CBZ by a combined experimental and computational study. Our results demonstrated that CYPs-mediated region-selective hydroxylation was a major metabolism pathway for CBZ in liver microsomes from various species including rat, mouse, minipig, dog, rabbit, guinea pig, monkey, cow and human, and the metabolite was biosynthesized and well-characterized as 6-OH-CBZ. CYP1A displayed a predominant role in the region-selective hydroxylation of CBZ that could attenuate its toxicity through converting it into a less toxic metabolite. Meanwhile, five other common pesticides including chlorpyrifos-methyl, prochloraz, chlorfenapyr, chlorpyrifos, and chlorothalonil could significantly inhibit the region-selective hydroxylation of CBZ, and consequently remarkably increased CBZ exposure in vivo. Furthermore, computational study clarified the important contribution of the key amino acid residues Ser122, and Asp313 in CYP1A1, as well as Asp320 in CYP1A2 to the hydroxylation of CBZ through hydrogen bonds. These results would provide some useful information for the metabolic profiles of CBZ by mammalian CYPs, and shed new insights into CYP1A-mediated metabolic detoxification of CBZ and its health risk assessment.