Contamination of drinking water by neonicotinoid insecticides in China: Human exposure potential through drinking water consumption and percutaneous penetration

Pharmacotherapeutic potential of malvidin to cure imidacloprid induced hepatotoxicity via regulating PI3K/AKT, Nrf-2/Keap-1 and NF-κB pathway

Imidacloprid (IMI) is one of the top-notch insecticides that adversely affects the body organs including the liver. Malvidin (MAL) is a natural flavonoid which exhibits a wide range of pharmacological properties. This research was designed to evaluate the protective ability of MAL to counteract IMI instigated liver toxicity in rats. Thirty-two rats were divided into four groups including control, IMI (5mg/kg), IMI (5mg/kg) + MAL (10mg/kg) and MAL (10mg/kg) alone treated group. The recommended dosages were administrated through oral gavage for 4 weeks. It was revealed that IMI intoxication disrupted the PI3K/AKT and Nrf-2/Keap-1 pathway. Furthermore, the activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), heme-oxygenase-1 (OH-1) and glutathione reductase (GSR) were reduced while upregulating reactive oxygen species (ROS) and malondialdehyde (MDA) levels after IMI treatment. Moreover, IMI poisoning increased the levels of ALT (Alanine aminotransferase), AST (Aspartate transaminase), and ALP (Alkaline phosphatase) while reducing the levels of total proteins and albumin in hepatic tissues of rats. Besides, IMI administration escalated the expressions of Bcl-2-associated protein x (Bax) and cysteine-aspartic acid protease-3 (Caspase-3) while downregulating the expressions of B-cell lymphoma 2 (Bcl-2). Similarly, IMI intoxication, increased the levels of Interleukin-6 (IL-6), Nuclear factor kappa-B (NF-κB), Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and the activity of cyclooxygenase-2 (COX-2). Furthermore, IMI disrupted the normal architecture of hepatic tissues. However, MAL treatment remarkably protected the liver tissues via regulating abovementioned disruptions.

An integrated approach to assess human health risk of neonicotinoid insecticides in surface water of the Yangtze River Basin, China

Neonicotinoids are widely used insecticides that have raised considerable concerns for both environmental and human health. However, there lack of comprehensive evaluation of their accumulation in surface water ecosystems and exposure to various human groups. Additionally, there's a distinct lack of scientific evidence describing the carcinogenic and non-carcinogenic impacts of neonicotinoids from surface water. Using an integrated approach employing the Relative Potency Factor (RPF), Hazard Index (HI), and Monte Carlo Simulation (MCS), the study assessed neonicotinoid exposure and risk to four demographic groups via dermal contact and mistaken oral intake pathways in the Yangtze River Basin (YRB), China. Neonicotinoid concentrations range from 0.1 to 408.12 ng/L, indicating potential risk (10-3 to 10-1) across the studied demographic groups. The Incremental Lifetime Cancer Risk (ILCR) for dermal contact was within a moderate range of 2.00 × 10-3 to 1.67 × 10-2, while the mistaken oral intake was also within a moderate range of 3.07 × 10-3 to 7.05 × 10-3. The Hazard Index (HI) for dermal exposure ranged from 1.49 × 10-2 to 0.125, while for mistaken oral intake, it varied between 2.69 × 10-2 and 0.14. The findings highlight the importance of implementing specific interventions to address neonicotinoid exposure, especially among demographic groups that are more susceptible. This research underscores the urgent need for targeted strategies to address neonicotinoid risks to vulnerable populations within the YRB while contributing to insights for effective policies to mitigate neonicotinoid exposure in surface water ecosystems globally.

Neonicotinoid insecticides and metabolites levels in neonatal first urine from southern China: Exploring links to preterm birth

Neonicotinoids (NEOs) have indeed become the most widely used insecticides worldwide. Concerns have been raised about their potential impact on newborns due to maternal exposure and their unique neurotoxic mode of action. However, it is still poorly understood whether in utero exposure of pregnant women to environmental NEOs and their metabolites can cause carryover effects on vulnerable newborns and subsequent health consequences. In this study, we determined the concentrations of 13 NEOs and their metabolites in the first urine collected from 92 newborns, both preterm and full-term, in southern China during 2020 and 2021. NEOs and their metabolites were identified in 91 urine samples, with over 93% of samples containing a cocktail of these compounds, confirming their maternal-fetal transfer. N-desmethyl-acetamiprid, imidaclothiz, clothianidin and flonicamid were the most commonly detected analytes, with detection frequencies of 59-87% and medians of 0.024-0.291 ng/mL in the urine. The relative abundance of imidaclothiz was significantly higher in preterm newborns, those with head circumferences below 33 cm, birth lengths less than 47 cm, and weights below 2500 g (p < 0.05). When comparing newborns in the 2nd quartile of imidaclothiz concentrations with those in the 1st quartile, we observed a significant increase in the odds of preterm outcomes in the unadjusted model (odds ratio = 3.24, 95% confidence interval = 1.02-10.3). These results suggest that exposure to elevated concentrations of imidaclothiz may be associated with preterm birth.

Integrated Electrochemical Oxidation and Biodegradation for Remediation of a Neonicotinoid Insecticide Pollutant

A novel integrated electrochemical oxidation (EO) and bacterial degradation (BD) technique was employed for the remediation of the chloropyridinyl and chlorothiazolyl classes of neonicotinoid (NEO) insecticides in the environment. Imidacloprid (IM), clothianidin (CL), acetamiprid (AC), and thiamethoxam (TH) were chosen as the target NEOs. Pseudomonas oleovorans SA2, identified through 16S rRNA gene analysis, exhibited the potential for BD. In EO, for the selected NEOs, the total percentage of chemical oxygen demand (COD) was noted in a range of 58-69%, respectively. Subsequently, in the biodegradation of EO-treated NEOs (BEO) phase, a higher percentage (80%) of total organic carbon removal was achieved. The optimum concentration of NEOs was found to be 200 ppm (62%) for EO, while for BEO, the COD efficiency was increased up to 79%. Fourier-transform infrared spectroscopy confirms that the heterocyclic group and aromatic ring were degraded in the EO and further utilized by SA2. Gas chromatography-mass spectroscopy indicated up to 96% degradation of IM and other NEOs in BD (BEO) compared to that of EO (73%). New intermediate molecules such as silanediamine, 1,1-dimethyl-n,n'-diphenyl produced during the EO process served as carbon sources for bacterial growth and further mineralized. As a result, BEO enhanced the removal of NEOs with a higher efficiency of COD and a lower consumption of energy. The removal efficiency of the NEOs by the integrated approach was achieved in the order of AC > CL > IM > TH. This synergistic EO and BD approach holds promise for the efficient detoxification of NEOs from polluted environments.

Microbial degradation mechanism and pathway of the insecticide thiamethoxam by isolated Bacillus Cereus from activated sludge

The high water solubility and ecotoxicity of thiamethoxam (TMX) is a potential hazard to ecosystems and human health. Here, a strain of Bacillus cereus with high TMX degradation activity was isolated from the sediment of the A2O process in the wastewater treatment plant and was able to utilize TMX as its sole carbon source. Under different environmental conditions, the degradation efficiency of TMX by Bacillus cereus-S1 (strain S1) ranged from 41.0% to 68.9% after 216 h. The optimum degradation conditions were DO = 3.5 mg/L and pH 9.0. The addition of an appropriate carbon-to-nitrogen ratio could accelerate the degradation of TMX. A plausible biodegradation pathway has been proposed based on the identified metabolites and their corresponding degradation pathways. TMX can be directly converted into Clothianidin (CLO), TMX-dm-hydroxyl and TMX-Urea by a series of reactions such as demethylation, oxadiazine ring cleavage and C=N substitution by hydroxy group. The main products were TMX-dm-hydroxyl and TMX-Urea, the amount of CLO production is relatively small. This study aims to provide a new approach for efficient degradation of TMX; furthermore, strain S1 is a promising biological source for in situ remediation of TMX contamination.

Associations between maternal serum neonicotinoid pesticide exposure during pregnancy and newborn telomere length: Effect modification by sampling season

BACKGROUND

An increasing amount of evidence suggests that telomere length (TL) at birth can predict lifespan and is associated with chronic diseases later in life, but newborn TL may be affected by environmental pollutants. Neonicotinoids (NEOs) are widely used worldwide, and despite an increasing number of studies showing that they may have adverse effects on birth in mammals and even humans, few studies have examined the effect of NEO exposure on newborn TLs.

OBJECTIVE

To investigate the effects of prenatal exposure to NEOs and the interactions between NEOs and sampling season on newborn TL.

METHODS

We conducted a prospective cohort study of 500 mother-newborn pairs from the Guangxi Zhuang Birth Cohort. Ultraperformance liquid chromatographymass spectrometry was used to detect ten NEOs in maternal serum, and fluorescence quantitative PCR was used to estimate the newborn TL. A generalized linear model (GLM) was used to evaluate the relationships between individual NEO exposures and TLs , and quantile g-computation (Qgcomp) model and Bayesian kernel machine regression (BKMR) model were used to evaluate the combined effect of mixtures of components.

RESULTS

The results of the GLM showed that compared with maternal TMX levels < LOD, maternal TMX levels < median were negatively correlated with newborn TL (-6.93%, 95% CI%: -11.92%, -1.66%), and the decrease in newborn TL was more pronounced in girls (-9.60%, 95% CI: -16.84%, -1.72%). Moreover, different kinds of maternal NEO exposure had different effects on newborn TL in different sampling seasons, and the effect was statistically significant in all seasons except in autumn. Mixed exposure analysis revealed a potential positive trend between NEOs and newborn TL, but the association was not statistically significant.

CONCLUSION

Prenatal exposure to TMX may shorten newborn TL, and this effect is more pronounced among female newborns. Furthermore, the relationship between NEO exposure and TL may be modified by the sampling season.

Assessing neonicotinoid accumulation and ecological risks in the aquatic environment of Yangtze River Basin, China

Neonicotinoids (NNIs) constitute commonly used pesticides across various regions, however, the lack of research and data on its long-term effects and threshold levels within specific ecosystems have left an important knowledge gap. This study aimed to comprehensively examine NNI concentrations and their potential impacts on human health and aquatic organisms in the region of the Yangtze River Basin (YRB). The study employed datasets on seven commonly applied NNIs across 244 surface water samples collected from 12 distinct geographic sites within the YRB. The relative potency factor was used to evaluate human exposure risks, while the species sensitivity distribution could estimate acute and chronic hazardous concentrations for 5% of species (HC5) for NNIs impacting aquatic organisms. Analysis revealed varying NNI concentrations across the sampled sites, with thiacloprid recording the lowest concentration at 0.1 ng L-1, and dinotefuran recording a high concentration of 408 ng L-1. The observation indicated NNI concentration declined at sampling sites downstream of the YRB. Infants were identified as the most vulnerable to NNI exposure, with an estimated daily intake of 40.8 ng kg-1 bw d-1. The acute HC5 was determined at 946 ng L-1 and a chronic HC5 at 338 ng L-1, to NNI hazards. These findings highlight the urgent need for a more comprehensive understanding of the ecological implications and hazards posed by NNIs within the YRB. Variations in NNI concentrations across sites, potential risks to human health, and increased vulnerability of aquatic organisms from this study underscore the necessity for further research and concerted efforts to mitigate these ecological threats in the region.

Health risks of neonicotinoids chronic exposure and its association with glucose metabolism: A case-control study in rural China

Since neonicotinoids (NNIs) are widely used around the world, they are extensively distributed in the environment and frequently occurred in humans. This study was conducted to assess the risk of NNIs residues in vegetables and fruits in Henan province, and evaluate the associations of NNIs single and mixed exposure with glucose metabolism, and further explore whether testosterone mediated these relationships in Henan rural population. The data of vegetables and fruits were collected from Henan Province in 2020-2021, and participants were drawn from the Henan Rural Cohort study. Hazard quotient (HQ) and hazard index (HI) were used to assess the risk of exposure to the individual and combined NNIs through vegetables or fruits intake. Relative potency factor (RPF) method was utilized to normalize each NNIs to imidacloprid (IMIRPF). Generalized linear models were used to explore the effects of each NNIs and IMIRPF on glucose metabolism. Weight quartile sum (WQS) regression and Bayesian kernel machine regression (BKMR) model were applied to estimate the effect of NNIs mixtures on glucose metabolism. Mediation analysis was employed to explore whether testosterone mediated these relationships. The HQs and HI in both vegetables and fruits were much lower than 1, which indicated that NNIs in vegetables and fruits were not expected to cause significant adverse effects. However, plasma natural logarithm nitenpyram (Ln_NIT), Ln_thiacloprid-amid (Ln_THD-A), and Ln_IMIeq were positively associated with type 2 diabetes mellitus (T2DM) (odds ratio (OR) (95% confidence interval (CI)): 1.12 (1.05, 1.19), 1.21 (1.10, 1.32), and 1.48 (1.22, 1.80)). Both WQS regression and BKMR models observed significantly positive associations between NNIs mixture exposure and T2DM. Testosterone partially mediated these associations among women (PE = 6.67%). These findings suggest that human NNIs exposure may impair glucose metabolism and could contribute to rising rates of T2DM, and it's necessary to regulate the use of pesticides in rural areas.

Accurate multi-objective prediction of CO2 emission performance indexes and industrial structure optimization using multihead attention-based convolutional neural network

The establishment of specific targets for the global carbon peaking and neutrality raises urgent requirements for prediction of CO₂ emission performance indexes (CEPIs) and industrial structure optimization. However, accurate multi-objective prediction of CEPIs is still a knotty problem. In the present study, multihead attention-based convolutional neural network (MHA-CNN) model was proposed for accurate prediction of 4 CEPIs and further provided the rational suggestions for further industrial structure optimization. The proposed MHA-CNN model introduces deep learning mechanism with efficient resolution strategies for training model overfitting, feature extraction, and self-supervised learning to acquire the adaptability for CEPIs. Multihead attention (MHA) mechanism plays important roles in influence weight interpretation of variables to facilitate the prediction performance of CNN on CEPIs. The MHA-CNN model presented its overwhelmingly superior performance to CNN model and long short-term memory (LSTM) model, two frequently-used models, in multi-objective prediction of CEPIs using 8 influence variables, which highlighted advantages of MHA module in multi-dimensional feature extraction. Additionally, contributions of influence variables to CEPIs based on MHA analyses presented relatively high consistency with the geographical distribution analyses, indicating the excellent capacity of the MHA module in variable weights identification and contribution dissection. Based on the more accurate prediction results by MHA-CNN than those by CNN and LSTM model, the increase in the tertiary industry and the decreases in the first and secondary industries are conducive to improvement of total-factor carbon emission efficiency and further enhancement of effective energy utilization in regions with inefficient carbon emissions. This study provides insights towards the critical roles of the proposed MHA-CNN model in accurate multi-objective prediction of CEPIs and further industrial structure optimization for improvement of total-factor carbon emission efficiency.

Rapid determination and health risk assessment of neonicotinoids in source water and tap water of the tropical Hainan Island, China

Neonicotinoids (NEOs) pesticides are widely used around the world, especially in the tropics with greater frequency and intensity. However, little is known about NEOs residue in drinking water of tropics. In this study, a highly efficient method using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established for determining eight NEOs in source water and tap water of Hainan Island, China. The method adopted a high-throughput direct aqueous injection without sample concentration steps, with a rapid analyzing period of 5.0 min, method detection limits (MDLs) in the range of 0.84-1.82 ng/L and the average recoveries ranged from 83% to 116%. NEOs were detected in all source water samples and at an upper level as compared with other parts of China. The most frequently detected NEO was imidacloprid with a detection frequency of 94%, followed by clothianidin (88%) and thiamethoxam (78%), with maximum concentrations of 86.4, 164, and 188 ng/L, respectively. Moreover, seasonal and spatial variations had remarkable impacts on NEO contamination in source water. Drinking water treatment processes removed approximately 20% of NEOs from surface water. However, 90% of tap water samples contained at least one NEO, With 3 samples' concentration of single NEO exceeding the acceptable value recommended by the European Union (100 ng/L). Therefore, the risk of human exposure through drinking water was evaluated for 4 age group and 2 genders. Young children aged 9 months to 3 years old were found to have the highest risk, with the median exposure up to 4 times greater than teenagers and adults. Next, water intake is likely only a small part of the daily intake of these individuals, thus the potential health problems caused by NEOs present in the tap water of Hainan should not be ignored.

Infantile Internal and External Exposure to Neonicotinoid Insecticides: A Comparison of Levels across Various Sources

Little is known about exposure of infants to neonicotinoid insecticides (NEOs). In this study, concentrations of six parent NEOs (p-NEOs) and N-desmethyl-acetamiprid (N-dm-ACE) were measured in urine and whole blood samples from infants, in addition to breast milk, infant formula, and tap water collected in South China. The p-NEO with the highest median concentration in urine (0.25 ng/mL) and blood (1.30) samples was dinotefuran (DIN), while imidacloprid (IMI) was abundant in breast milk (median: 0.27 ng/mL), infant formula (0.22), and tap water (0.028). The older infants (181-360 days) might face higher NEO and N-dm-ACE exposure than younger infants (0-180 days). Blood samples contained a significantly (p < 0.01) higher median concentration of ∑₆p-NEOs (2.03 ng/mL) than that of urine samples (0.41), similar to acetamiprid (ACE), IMI, thiacloprid (THD), DIN, and N-dm-ACE, suggesting that NEOs readily partition into blood. Furthermore, breast-fed infants tend to have higher exposure levels than formula-fed infants. Infant formula prepared with tap water augmented the daily intake of ∑NEOs. The external sources contributed 80% of the total dose to IMI and clothianidin (CLO) exposure, while other unknown sources contributed to ACE, THD, and DIN exposure in infants. To the best of our knowledge, this is the first study to assess levels and sources of infantile exposure to NEOs through internal and external exposure assessment.

First evidence of neonicotinoid insecticides in human bile and associated hepatotoxicity risk

Neonicotinoids (NEOs) are widely applied in agricultural lands and are widespread in different environments, accelerating threats to ecosystems and human health. A number of in vitro/in vivo studies have reported adverse effects of NEOs on mammalian health, but the link between NEO exposure and toxic effects on human liver remains unclear. We randomly recruited 201 participants and quantified eight commercialized NEOs in bile. High frequency and concentration of detection indicate low degradation of human liver on NEOs. The main NEOs are nitenpyram and dinotefuran, which contribute to about 86% of the total residual levels of eight NEOs, due to the highest solubility in bile and are not degraded easily in liver. In contrast, imidacloprid and thiacloprid are major compounds in human blood, according to previous studies, suggesting that individual NEOs behave differently in blood and bile distribution. There was no statistical difference in NEO residues between cancer and non-cancer participants and among the different participant demographics (e.g., age, gender, and body mass index). The serum hematological parameters -bile acid, total bilirubin, cholesterol and alkaline phosphatase -were positively correlated with individual NEO concentrations, suggesting that NEO exposure affects liver metabolism and even enterohepatic circulation. The study first examined the NEO residues in human bile and provided new insights into their bioavailability and hepatoxicity risk.

Neonicotinoid Insecticides and Their Metabolites Can Pass through the Human Placenta Unimpeded

Studies on neonicotinoid (NEO) exposure in pregnant women and fetuses are scarce, and transplacental transfer of these insecticides is unknown. In this study, parent NEOs (p-NEOs) and their metabolites (m-NEOs) were determined in 95 paired maternal (MS) and cord serum (CS) samples collected in southern China. Imidacloprid was the predominant p-NEO in both CS and MS samples, found at median concentrations of 1.84 and 0.79 ng/mL, respectively, whereas N-desmethyl-acetamiprid was the most abundant m-NEO in CS (median: 0.083 ng/mL) and MS (0.13 ng/mL). The median transplacental transfer efficiencies (TTEs) of p-NEOs and m-NEOs were high, ranging from 0.81 (thiamethoxam, THM) to 1.61 (olefin-imidacloprid, of-IMI), indicating efficient placental transfer of these insecticides. Moreover, transplacental transport of NEOs appears to be passive and structure-dependent: cyanoamidine NEOs such as acetamiprid and thiacloprid had higher TTE values than the nitroguanidine NEOs, namely, clothianidin and THM. Multilinear regression analysis revealed that the concentrations of several NEOs in MS were associated significantly with hematological parameters related to hepatotoxicity and renal toxicity. To our knowledge, this is the first analysis of the occurrence and distribution of NEOs in paired maternal-fetal serum samples.

Neonicotinoid insecticides promote breast cancer progression via G protein-coupled estrogen receptor: In vivo, in vitro and in silico studies

Neonicotinoid insecticides (NIs) have been widely detected in environmental media and human body with concentrations reaching hundreds of nanomolar to micromolar levels. However, the information about their human health toxicology and mechanism is deficient. Previous studies have implied that NIs might exert estrogenic disruption and promote breast cancer progression, but the molecular mechanism is unclear, especially the molecular initiating event. G protein-coupled estrogen receptor (GPER), as a candidate therapeutic target, plays vital roles in the development of breast cancer. This work aimed to reveal the potential mechanism through GPER pathway. Firstly, we screened the activities of seven most common NIs on GPER signal pathway by calcium mobilization assay. Clothianidin, acetamiprid (ACE), and dinotefuran activated GPER most potently and ACE displayed the highest agonistic activity with the lowest observed effective concentration (LOEC) of 1 μM. The molecular docking and dynamics simulation showed favored interaction trend between the NIs and GPER. The three NIs with GPER activity induced 4T1 breast cancer cells migration and ACE showed the highest potency with LOEC of 100 nM. ACE also induced 4T1 cells proliferation at high concentration of 50 μM and up-regulated GPER expression in a dose-dependent manner. We speculated that both the induction effects of ACE on 4T1 cells proliferation and migration might be owing to the activation and up-regulation of GPER. By using 4T1-Luc cells injected orthotopic tumor model, we found that ACE also promoted in-situ breast cancer growth and lung metastasis in normal mouse dependent on GPER. However, ACE only promoted in-situ breast cancer growth through GPER but not lung metastasis in ovariectomized mice, implying that the ACE-induced lung metastasis should be related to endogenous estrogen from ovary. Overall, we demonstrated that NIs promoted breast cancer progression via GPER pathway at human related exposure levels and their female health risks need urgent concerns.

Variability of urinary biomarkers of neonicotinoid insecticides in Chinese population: Implications for human exposure assessment

Neonicotinoids are a class of the most widely used insecticides worldwide with a short biological half-life. The levels of neonicotinoids and their metabolites in urine have been detected as biomarkers for human exposure assessment. To understand the reliability of a single measurement of urinary neonicotinoid biomarkers in representing a true longer-term average exposure, in this study we evaluated the temporal variability of 14 neonicotinoids and/or their metabolites over one year in 114 Chinese young adults. The detection rates of 14 neonicotinoid biomarkers ranged from 18% to 100%. The intraclass correlation coefficients (ICCs) of most neonicotinoid biomarkers indicated poor (ICC <0.4) reproducibility in spot urine samples during 1-week, 1-month, or 1-year periods, except for 5-hydroxy-imidacloprid (5-OH-IMI) within 1-week showing fair to good reproducibility (ICC = 0.40). Log-transformed 5-OH-IMI, dinotefuran, 1-methyl-3-(tetrahydro-3-furylmethyl) urea, N-desmethyl-acetamiprid, and N-desmethyl-thiamethoxam required a minimum of 2-4 spot urine samples over one year to obtain a reliable exposure evaluation. Using two or three spot urine samples to categorize the "true" exposure of the highest tertile indicated the higher specificities (0.60-1.00) than the sensitivities (0.24-0.93). We recommend that at least 2-4 spot urine samples are used to assess 1-year neonicotinoid exposure and seasonal variations should be considered when scheduling urine sample collection. This study provides a reference for appropriate sampling method and research design for the exposure assessment of neonicotinoids in biomonitoring and epidemiological studies.

Identification and quantitation of the novel insecticide sulfoxaflor and its metabolites in floral nectar from Salvia splendens Ker Gawl. (Lamiaceae)

Sulfoxaflor is a new systemic insecticide developed as a replacement for older neonicotinoids which are known to be toxic to pollinators. However, its metabolism in nectar and effect on nectar biosynthesis have not been investigated. After soil and foliar application, sulfoxaflor and its main metabolites in soil, leaf and Salvia splendens nectar, were measured by liquid chromatography coupled with triple quadrupole mass spectrometer (LC-MS/MS). The chemical composition between the clean and sulfoxaflor spiked nectar were also compared. The activities of two possible sulfoxaflor detoxifying enzymes in S. splendens nectar, nitrile hydratase and glutathione-s-transferase, were measured by LC-MS and spectrophotometry. S. splendens nectar proteome was investigated by high-resolution orbitrap-based MS/MS to screen for sulfoxaflor detoxifying relevant proteins. S. splendens could absorb sulfoxaflor through root or leaf surface and secrete a proportion of sulfoxaflor along with its metabolites into the nectar. After soil application, sulfoxaflor's low toxic metabolite X11719474 was dominant in the nectar and reached an average concentration of 8905 ppb. However, after foliar application, sulfoxaflor was dominant over its metabolites in the nectar. S. splendens nectar has no nitrile hydratase and glutathione-s-transferase activity and none of the 106 proteins identified in the nectar were predicted to function in detoxifying sulfoxaflor. Soil and foliar sulfoxaflor application can result in different profiles of sulfoxaflor and its metabolites presented in the nectar. However, sulfoxaflor had no effects on S. splendens nectar secretion and chemical composition and cannot be directly detoxified by components in the nectar.

Detection of Neonicotinoids in agriculture soil and degradation of thiacloprid through photo degradation, biodegradation and photo-biodegradation

The social and ecological influence of Neonicotinoids (NEOs) usage in agriculture sector is progressively higher. There are seven NEOs insecticides widely used for the insects control. Among the NEOs, thiacloprid (THD) was extensively used for insect control during crop cultivation. This study targets to analyse the contamination levels of NEOs in agricultural soil and identify photo-biodegradation of THD degradation using pure isolates and mixed consortium. The photo degradation (PD), biodegradation (BD) and photo-biodegradation (PBD) of THD were compared. The corn field agricultural soils were polluted by four NEOs, among them THD had greater contamination level (surface soil: 3901.2 ± 0.04 μg/g) and (sub-surface soil: 3988.6 ± 0.05 μg/g). Three soil free enriched bacterial strains following Bacillus atrophaeus (PB-2), Priestia megaterium (PB-3) (formerly known as Bacillus megaterium), and Peribacillus simplex (PB-4) (formerly known as Bacillus simplex) were identified by microbiological and molecular 16s rRNA gene sequencing. The PD, BD and PBD of THD were conducted and degradation rate was detected by instrument UPLC-MS-MS. The PBD process with blue-LEDs showed better THD degradation efficiency than PD and BD, where the specific THD degradation rate was 85 ± 0.2%, 87 ± 0.5%, and 89 ± 0.3%, respectively for PB-2, PB-3 and PB-4. Then, the photo-biodegradation performance is greater at 150, 175, 200 rpm, pH 7.0-9.0, and temperature 30-35 °C. After the PBD system deliver four intermediate metabolites, the THD degradation process maybe through nitro reduction, hydroxylation and oxidative cleavage pathway.

Widespread pesticide contamination of drinking water and impact on cancer risk in Brazil

Pesticides, which are associated with endocrine dysfunction, immunological dysregulation, and cancer, are widespread sources of drinking water contamination. The state of Paraná has a population of 11 million, is the second largest grain producer in Brazil and is a leading consumer of pesticides. In this study, we analyzed the extent of drinking water contamination from 11 proven, probable, or potentially carcinogenic pesticides (alachlor, aldrin-dieldrin, atrazine, chlordane, DDT-DDD-DDE, diuron, glyphosate-AMPA, lindane-γ-HCH, mancozeb-ETU, molinate, and trifluralin) in 127 grain-producing municipalities in the state of Paraná. Extensive contamination of drinking water was found, including legacy pesticides such as aldrin-dieldrin (mean 0.047 ppb), DDT-DDD-DDE (mean: 0.07), chlordane (mean: 0.181), and lindane-HCH (mean: 2.17). Most of the municipalities were significantly above the maximum limits for each one of the currently allowed pesticides (67% for alachlor, 9.44% for atrazine, 96.85% for diuron, 100% for glyphosate-AMPA, 80.31% for mancozeb-ETU, 91.33% for molinate, and 12.6% for trifluralin). Ninety-seven percent of municipalities presented a sum of all pesticides at levels significantly above (189.84 ppb) the European Union preconized limits (<0.5 ppb). Using the mean pesticide concentration in water (ppb), the exposed population for each municipality, and the benchmark cancer risk for pesticides, we estimated the minimum number of cancer cases attributable to pesticide-contaminated drinking water during the period (total of 542 cases). More than 80% were attributed to mancozeb-ETU and diuron. Glyphosate-AMPA and diuron-attributable cases strongly correlated with the total cancer cases in the same period (R = 0.8117 and 0.8138, respectively) as well as with breast cancer cases (R = 0.7695 and 0.7551, respectively). Water contamination was significantly correlated with the sum of the estimated cancer cases for all 11 pesticides detected in each city (R = 0.58 and p < 0.0001). These findings reveal extensive contamination of drinking water in the state of Paraná and suggest that contamination may increase the risk of cancer in this region.

Inference of emission history of neonicotinoid pesticides from marine sediment cores impacted by riverine runoff of a developed agricultural region: The Pearl River Basin, China

Neonicotinoids (NEOs), as the most-consumed pesticides on a global scale, have posed a serious threat to human health and ecological environment. Information regarding the emission history of NEOs is of great importance to improve the prediction of their environmental loading and biological risk potential. In the present study, contamination levels and compositions of 12 NEOs were identified in 8 sediment cores from the Lingdingyang Estuary, which was impacted by agricultural emissions in riverine runoff of the Pearl River Basin for centuries. The total concentration of 12 target NEOs (∑₁₂NEOs) ranged from 0.02 to 69.5 ng/g dw along the sediment core profile, with a mean of 12.9 ± 15.9 ng/g dw. Net deposition fluxes and concentrations of 5 parent NEOs experienced a remarkable exponential increase in the vertical profile of sediment cores, except for imidacloprid (IMI). Despite the similar exponential growth before 2012, subsequent decreased levels of IMI in historical sediment indicated its gradual replacement by other NEOs. IMI was the NEO with the highest frequency of 80.3% and the highest mean concentration of 7.66 ± 8.76 ng/g dw. The ecological risk assessment of NEOs suggests that 65.1% of sediment samples exceeded the chronic threshold for aqueous organisms using equilibrium partitioning approach. Since downward diffusion of NEOs in the Lingdingyang Estuary was rectified by their rapid desorption, the sedimentary record probably provided an accurate illustration of agricultural NEO emissions in the Pearl River Basin, China. The recent NEO inventory in the adjacent waters of core sites was estimated with a mean of 76.8 tons/yr. This study provides insights into the role of agricultural emission in riverine runoff in the environmental loads of NEOs in the historical sediment.

Designing NAZO@BC electrodes for enhanced elimination of hydrophilic organic pollutants in heterogeneous electro-Fenton system: Insights into the detoxification mediated by 1O2 and •OH

Hydrophilic organic pollutants (HLOPs) in effluents of wastewater treatment plants are more prevalent than hydrophobic counterparts, therefore development of upstream processes that can effectively enhance the removal of HLOPs can substantially enhance overall treatment performance. To bridge this gap, 3D electrodes made of biochar-supported Al-ZnO nanoparticles (NAZO@BC) applied in heterogeneous electro-Fenton (EF) system, abbreviated as NBE-EF system, is rationally designed for enhanced elimination of HLOPs in wastewater. Our analysis indicates the NBE-EF system results in an efficient THM elimination, 42.4 times greater than that of conventional EF system. MoS₂ as an efficient cocatalyst plays an important role in the conversion from Fe(III) to Fe(II). Singlet oxygen (¹O₂) and hydroxyl radical (•OH) are identified as the primary reactive oxygen species (ROS) in the NBE-EF system. NAZO@BC electrodes could concentrate HLOPs on their surface and degrade it effectively, achieving also a self-cleaning effect. Effective elimination of four HLOPs, i.e., thiamethoxam (THM), dinotefuran (DIN), nitenpyram (NIT), and acetamiprid (ACE), demonstrated the high degradation performance of the NBE-EF system, even at neutral and alkaline conditions. This study provides a new approach for enhanced elimination of HLOPs in wastewater treatment and mechanical insights into degradation pathways and toxicity attenuation.

On-site rapid and simultaneous detection of acetamiprid and fipronil using a dual-fluorescence lab-on-fiber biosensor

A dual-fluorescence lab-on-fiber biosensor was developed for the rapid and simultaneous on-site determination of acetamiprid and fipronil, based on time-resolved effect and indirect competitive immunoassay principle. The optical fiber modified with two hapten-protein conjugates serves as a bifunctional bio-probe. The dual-color fluorescent reporters were prepared via labeling acetamiprid and fipronil antibodies with Cy5.5 and Alexa Fluor 555, which were excited at 635-nm and 520-nm laser wavelengths, respectively. In the presence of targets, the binding sites of corresponding antibodies were occupied and less antibodies were connected to the probe surface, resulting in the reduction of fluorescence signal. The concentration of acetamiprid and fipronil was determined by measuring the fluorescence signals at 568 nm and 702 nm (emission wavelengths), respectively. Under optimal conditions, the linear response range was 14.2-225.4 ng/L for acetamiprid and 25.1-162.8 ng/L for fipronil, and the limit of detection was 6.51 ng/L and 17.8 ng/L for acetamiprid and fipronil, respectively. The method was successfully applied to the simultaneous detection of acetamiprid and fipronil in three environmental samples, and the recoveries were between 90 and 128%. The dual-fluorescence lab-on-fiber biosensor provides a feasible platform for simultaneous and rapid detection of multiple pesticide residues. A dual-fluorescence lab-on-fiber biosensor was developed for the rapid and simultaneous on-site determination of acetamiprid and fipronil. A bifunctional bio-probe was prepared from the optical fiber modified with two hapten-protein conjugates. Acetamiprid and fipronil antibodies were labeled with different fluorophores and used as dual-color fluorescent reporters.

Construction of hydrophilic hypercrosslinked polymer based on natural kaempferol for highly effective extraction of 5-nitroimidazoles in environmental water, honey and fish samples

A series of novel hydroxyl-functional hypercrosslinked polymers (named as HCPs-Kae) were fabricated using natural and environmentally benign kaempferol as monomer via one-step Friedel-Crafts reaction. The prepared HCP-Kae1-24 h exhibited large surface area, good hydrophilicity and excellent adsorption performance to 5-nitroimidazoles (5-NDZs). Thus, by applying HCP-Kae1-24 h as a solid-phase extraction adsorbent, a sensitive method was developed for enrichment of 5-NDZs including metronidazole, ronidazole, secnidazole, dimetridazole and ornidazole prior to high performance liquid chromatography analysis. Under the optimum conditions, good linearities were achieved in the range of 0.10-100.0 ng mL^-1 for water, 1.3-500.0 ng g^-1 for honey, and 1.7-100.0 ng g^-1 for fish meat. The detection limits of the method were 0.03-0.05 ng mL^-1, 0.4-1.0 ng g^-1, 0.5-1.0 ng g^-1 for water, honey and fish meat, respectively. High method recovery was obtained in the range of 84-118% with relative standard deviations lower than 8.9%. The established method was successfully applied to the detection of 5-NDZs in environmental water, honey and fish samples. This work provides a new strategy for constructing hydroxyl-functional HCPs by using natural resource as robust adsorbent for adsorption/extraction applications.

Neonicotinoids: mechanisms of systemic toxicity based on oxidative stress-mitochondrial damage

Neonicotinoids are the most widely used pesticides in the world. However, research studies have shown that it can affect the cognitive abilities and health of non-target bees and other wild pollinators by inducing DNA damage, apoptosis and mitochondrial damage, injure to its central nervous system, and it is even developmentally neurotoxic to mammals and humans, with mitochondria being an important target of neonicotinoids. Therefore, this article reviews the role of mitochondrial morphology, calcium ions (Ca²⁺) homeostasis, respiratory function, apoptosis, and DNA damage in neonicotinoids-induced systemic toxicity. Additionally, it evaluates the protective effects of various active substances including vitamin C, N-acetylcysteine (NAC), curcumin (CUR), glutathione reduced (GSH), caffeic acid phenethyl ester (CAPE), resveratrol, and thymoquinone (TQ) on neonicotinoids-induced toxicity. This review manuscript found that mitochondria are important targets to neonicotinoids. Neonicotinoids can cause DNA damage, apoptosis, protein oxidation, and lipid peroxidation in non-target organisms by altering mitochondrial Ca²⁺ homeostasis, inhibiting mitochondrial respiration, and inducing reactive oxygen species (ROS) production. Several active substances (vitamin C, NAC, CUR, GSH, resveratrol, CAPE, and TQ) play a protective role against neonicotinoid-induced systemic toxicity by inhibiting ROS signaling pathways, apoptosis, and lipid peroxidation. This review manuscript emphasizes the importance and urgency of the development of neonicotinoid antidotes, emphasizes the prospect of the application of targeted mitochondrial antidotes, and prospects the development of neonicotinoid antidotes in order to provide some strategies for the prevention of neonicotinoid toxicity.

Suspect, non-target and target screening of pharmaceuticals and personal care products (PPCPs) in a drinking water system

Drinking water quality and safety are very important in protecting human health. Chemical contaminants in drinking water system have become an increasing concern. Our knowledge about what chemicals are present in drinking water is still limited. Here we screened chemicals of emerging concern in a conventional drinking water system based on suspect, non-target screening and target analysis, and assessed their variations in different seasons and different treatment units. Overall, 720 chemicals were identified with HRMS databases from the suspect and non-target screening and 48 chemicals in five categories were further confirmed with the high confidence level, with predominance of pharmaceuticals and personal care products (PPCPs) and pesticides. Four compounds are newly found in aquatic environment with no literature or chemical occurrence data record. Temporal variations and variable removals were observed for these chemicals in the system. Target analysis of 110 PPCPs showed detection of 21, 19 and 22 compounds in the drinking water treatment plant with a concentration range of 0.11-844 ng/L in the three seasons, but only 8, 9 and 15 compounds detected in tap water (0.16-32.5 ng/L). The variations of the detected chemicals were less obvious in tap water, with most having concentrations below 2 ng/L. The results indicated efficient removal for most PPCPs in the drinking water system. The findings from this study demonstrated the strong capability of combined non-target screening and target analysis in identifying and assessing various organic chemicals in drinking water system.

Accurate prediction and further dissection of neonicotinoid elimination in the water treatment by CTS@AgBC using multihead attention-based convolutional neural network combined with the time-dependent Cox regression model

Imidacloprid (IMI), as the most widely used neonicotinoid insecticide, poses a serious threat to the water ecosystem due to the inefficient elimination in the traditional water treatment. Chitosan (CTS)-stabilized biochar (BC)-supported Ag nanoparticles (CTS@AgBC) are applied to eliminate the IMI in the water treatment effectively. Batch experiments depict that the modification of BC by CTS and Ag nanoparticles remarkably improve its adsorption performance. The pseudo-second-order and Elovich models have good performance in simulating the adsorption processes of CTS@AgBC and BC. This indicates that the chemical adsorption on real surfaces plays the dominant role in the adsorption of IMI by CTS@AgBC and BC. In addition, the multihead attention (MHA)-based convolutional neural network (CNN) combined with the time-dependent Cox regression model are initially applied to predict and dissect the adsorption elimination processes of IMI by CTS@AgBC. The proposed MHA-CNN model achieves more accurate concentration prediction of IMI than traditional models. According to influence weights by MHA module, biochar category, pH, and treatment temperature are considered the three dominant environmental variables to determine the IMI elimination processes. This study provides insights into roles of environmental variables in the elimination of IMI by CTS@AgBC and the accurate prediction of IMI concentration.

Target and Suspect Screening of Urinary Biomarkers for Current-use Pesticides: Application of a Simple Extraction Method

Pesticide residues pose a great threat to human health. Biomonitoring with urine samples has often been used to assess pesticide exposure to humans, and identifying appropriate biomarkers is a premise of success. Current-use pesticides (CUPs) including neonicotinoids tend to be transformed in an organism, and thus the biomonitoring studies focusing on parent compounds alone may underestimate their risk. It is imperative to develop effective methods to analyze CUPs and their metabolites simultaneously and to identify viable metabolites as urinary biomarkers. For analyzing xenobiotics in urine, we optimized CH₃ COCH₃ -MgSO₄ extraction coupled with a high-performance liquid chromatography-tandem mass spectrometry detection method. The method had sensitive method detection limits (0.11-1.39 ng/ml), low matrix effects, and satisfactory recovery and precision (49.4% ± 7.2%-99.8% ± 17.8%) for neonicotinoids and their metabolites. Application of the method for real samples showed that children living in rural areas in South China were ubiquitously exposed to CUPs, including neonicotinoids, fipronil, and chlorpyrifos, and urinary residues were mainly in the form of metabolites. Suitable biomarkers were identified for individual neonicotinoids, including imidacloprid-olefin and imidacloprid-guanidine for imidacloprid, acetamiprid-N-desmethyl for acetamiprid, thiacloprid-amide for thiacloprid, and N-desmethyl-thiamethoxam and thiamethoxam for thiamethoxam. Three metabolites were mainly reported in urine samples, including imidacloprid-urea, thiacloprid-amide, and N-desmethyl-thiamethoxam. In addition, the method was also applied for suspect screening, and an additional metabolite (clothianidin-desmethyl-nitrosoguanidine) was identified, showing its potential application in suspect analysis. Environ Toxicol Chem 2022;41:73-80. © 2021 SETAC.

Pollution status, influencing factors and environmental risks of neonicotinoids, fipronil and its metabolites in a typical semi-closed bay in China

The occurrence, spatiotemporal variations, influence factors and environmental risks of eight common neonicotinoids (NEOs), fipronil, and three fipronil metabolites (fipronil and its metabolites are collectively referred to as FIPs) in different seasons from the estuary to the inner area of Jiaozhou Bay, China were comprehensively investigated. First- and second-generation NEOs were found to be the predominant pesticides in this area. The average contents of ∑NEOs and ∑FIPs from the estuary to the inner bay decreased from 12.99 ng/L to 0.82 ng/L and from 1.10 ng/L to 0.17 ng/L, respectively. NEO and FIP concentrations were higher in summer and autumn. High ∑NEO content is distributed in main inflow rivers, such as Dagu River and Licun River, which are influenced by pesticide application. NEO concentrations in all rivers were high upstream and low downstream because of the influence of heavy rainfall and seawater dilution in summer. NEO concentrations were high along the coast and low at the mouth and center of Jiaozhou Bay in summer and autumn and evenly distributed in winter and spring. Temperature has a great influence on most NEOs and FIPs owing to its effect on their degradation. Nitrogen-containing nutrients have an important influence on the distribution of fipronil and acetamiprid, which may be due to the activity of nitrogen-containing functional groups in their structure. Only Licun River, Dagu River and Haibo river sewage treatment plant in summer posed a certain risk of chronic toxicity for NEOs using the new threshold established by the species sensitive distribution (SSD) method for Chinese native aquatic lives. These findings should arouse people's attention.

Selected transformation products of neonicotinoid insecticides (other than imidacloprid) in drinking water

Several transformation products (or metabolites) of neonicotinoid insecticides (NNIs) have been detected in drinking water, such as desnitro-imidacloprid and imidacloprid-urea. However, data on the occurrences of the metabolites of NNIs (mNNIs) in drinking water are mainly limited to the imidacloprid metabolites. To identify whether the potential metabolites of other widely used NNIs (such as acetamiprid, clothianidin, and thiamethoxam) occur in drinking water and to characterize their distribution profiles, twelve selected (mainly urea and desnitro/decyano) metabolites of NNIs were measured in drinking water samples (n = 884, including n = 789 for tap water, and n = 95 for shallow groundwater) that were collected from 32 provinces in mainland China and Hong Kong. Nearly 90% of the drinking water samples contained the detected mNNI residues. Among the selected mNNIs, thiamethoxam-urea (THM-urea: 76%) and decyano-acetamiprid (decyano-ACE: 73%) were frequently detected (median: 0.94 and 0.25 ng/L, respectively), which were followed by clothianidin-urea (CLO-urea: 45%), desnitro-thiamethoxam (DN-THM: 38%), and other mNNIs (detected in less than 30% of the water samples). Surface-water-sourced tap water had an approximately 8-10 times higher median cumulative concentration (ng/L) of the selected mNNIs (ΣmNNIs: 3.88) than the deep groundwater-sourced tap water (0.53) and groundwater that was directly used as drinking water (0.38). Higher ratios of THM-urea accounted for ΣTHM in north and northwest China than in south China could be partly explained by the decreasing soil pH values from north to south in China. The higher ratios of decyano-ACE accounted for ΣACE in south China than in north and northwest China could be attributable to the lower soil pH levels, higher temperatures, and greater light intensities in south China. The THM-urea, decyano-ACE, and ΣmNNIs levels in cities were found to be significantly higher than those in nonurban areas. The THM-urea levels in seven drinking water samples from Guangxi and Henan Provinces exceeded the guideline limit (100 ng/L) of the European Union. This is the first study to identify THM-urea, decyano-ACE, CLO-urea, and DN-THM in drinking water. To better assess the mass loadings of NNIs in drinking water, mNNIs should be considered in further studies.

Crucial roles of 3D-MoO2-PBC cocatalytic electrodes in the enhanced degradation of imidacloprid in heterogeneous electro-Fenton system: Degradation mechanisms and toxicity attenuation

Imidacloprid (IMI), as the most-consumed pesticide, has posed a severe threat to the water ecosystem due to its recalcitrance and inefficient elimination in the traditional wastewater treatment. Herein, a heterogeneous electro-Fenton (EF) system coupled with 3D-MoO₂-porous biochar (PBC) cocatalytic electrodes, abbreviated as 3D-MPE-EF, is initially applied to promote the elimination of IMI in the agrochemical wastewater from pesticide production. The elimination rate of IMI by 3D-MPE-EF system is 18.15 times higher than that by traditional EF system at pH 7.0. The utilization of 3D-MoO₂-PBC electrodes sufficiently compensates for inherent deficiencies of traditional EF system. The circular utilization of Fe is also addressed by 3D-MoO₂-PBC cocatalytic electrodes to reduce the consumption of Fe²⁺ and the deposition of iron mud. Through comparison, MoO₂ is considered the most appropriate cocatalyst in terms of the reutilization of Fe and degradation of IMI. Eight mechanisms are identified in the degradation pathways of IMI by UPLC-Q-TOF-MS. The ecotoxicities of IMI are remarkably attenuated in the 3D-MPE-EF system. This study provides insights into the roles of 3D-MoO₂-PBC cocatalytic electrodes in the enhanced elimination of IMI in heterogeneous EF system.

Photo-biodegradation of imidacloprid under blue light-emitting diodes with bacteria and co-metabolic regulation

Imidacloprid (IMI) is existence in the soil environment with a half-life habitually more than hundred days. This study targets to determine, identify and characterize photo-biodegradation bacteria from neonicotinoids (NEOs) contaminated agricultural field soils. The sub-surface soil had a higher level contamination of NEOs, in specifically greater concentration of IMI (3445.2 ± 0.09 μg/g) and thiacloprid (4084.4 ± 0.09 μg/g) has been found. Three bacteria Ralstonia pickettii (PBMS-2), Bacillus cereus (PBMS-3) and Shinella zoogloeoides (PBMS-4) was identified from soil-free stable enrichment cultures. The biodegradability of IMI (50 mg L^-1) by three bacteria under different colors of light-emitting diodes (LEDs) with a constant 12 V power supply was tested and found that the blue-LEDs had greatest efficiency in supporting biodegradation of IMI which is called photo-biodegradation. In specific, the rate of photo-biodegradation of IMI by Ralstonia pickettii (87%), Bacillus cereus (80%) and Shinella zoogloeoides (80%) was measured. Besides this study also tested the effect of aeration (rpm), pH, and temperature on photo-biodegradation of IMI. There were seven intermediate metabolites were measured as biodegradation products of IMI under photo-biodegradation conditions and they are; IMI-urea, IMI-desnitro, 6-chloronicotinic acid, 6-hydroxy nicotinic acid, IMI- aminoguanidine, IMI-nitrosoguanidine and 4,5-hydroxy IMI, these metabolites are may non-toxic to the environment.