Effects of Neonicotinoid Pesticides on Promoter-Specific Aromatase (CYP19) Expression in Hs578t Breast Cancer Cells and the Role of the VEGF Pathway

Occurrence and risk assessment of current-use pesticides in a tropical drinking water source reservoir in Hainan Province, China

The agricultural sector plays a pivotal role in Hainan Province, China; therefore, the utilization of pesticides is indispensable. The current ban on traditional pesticides and ongoing replacement of current-use pesticides (CUPs) have not been accompanied by extensive research on the presence of CUPs in reservoirs, which are vital centralized sources of drinking water. In this study, 26 CUPs was investigated in a drinking water source reservoir, the surrounding watershed, and the surrounding agricultural and domestic discharge water in Hainan Province. The predominant detected CUPs in the study area were clothianidin (CLO), thiamethoxam (THM), acetamiprid (ACE), imidacloprid (IMI), and dichlorvos (DCH). Neonicotinoids (NNIs) were the primary type of pesticide contamination in the study area, with a concentration ranging from not detected (n.d.) to 755 ng L-1 (median of 71.0 ng L-1). The upstream watersheds of the reservoir were primarily contaminated due to agricultural activities, and the highest concentration of individual CUPs, ranging from 102 to 821 ng L-1 (median of 468 ng L-1), was found in agricultural source water. Source identification analysis revealed that the presence of CUPs in the reservoir primarily stemmed from three types of activities: the cultivation of fruit trees around the reservoir, the daily activities of residents, and the agricultural practices in the upstream watershed basin. Risk assessment indicated that DCH, IMI, and THM posed moderate or high risks to aquatic organisms, with an emphasis on the effects of NNIs. The chronic cumulative risk assessment of NNIs was conducted by the relative potency factor approach, and it indicated that infants and young children were the most vulnerable groups and exhibited heightened susceptibility. The potential exposure to NNIs through drinking water was below the recommended relative chronic reference dose, thereby posing no discernible health risks. The results of this study will support the regulation of CUPs in drinking water sources.

Imidacloprid-induced lung injury in mice: Activation of the PI3K/AKT/NF-κB signaling pathway via TLR4 receptor engagement

Significant impairment of pulmonary function has been demonstrated through long-term exposure to neonicotinoid insecticides, such as imidacloprid (IMI). However, the underlying mechanisms of lung injury induced by IMI remain unclear. In this study, a mouse model of IMI-induced pulmonary injury was established, and the toxicity and lung damage were assessed through mouse body weight, organ index, hematological parameters, and histopathological analysis of lung tissues. Furthermore, metabolomics and transcriptomics techniques were employed to explore the mechanistic aspects. Results from the toxicity assessments indicated that mouse body weight was significantly reduced by IMI, organ index was disturbed, and hematological parameters were disrupted, resulting in pulmonary injury. The mechanistic experimental results indicate that the differences in metabolites and gene expression in mouse lungs could be altered by IMI. Validation of the results through combined analysis of metabolomics and transcriptomics revealed that the mechanism by which IMI induces lung injury in mice might be associated with the activation of the TLR4 receptor, thereby activating the PI3K/AKT/NF-κB signaling pathway to induce inflammation in mouse lungs. This study provided valuable insights into the mechanisms underlying IMI-induced pulmonary damage, potentially contributing to the development of safer pest control strategies. The knowledge gained served as a robust scientific foundation for the prevention and treatment of IMI-related pulmonary injuries.

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.

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.

Typical neonicotinoids and organophosphate esters, but not their metabolites, adversely impact early human development by activating BMP4 signaling

Recent studies have highlighted the presence of potentially harmful chemicals, such as neonicotinoids (NEOs) and organophosphate esters (OPEs), in everyday items. Despite their potential threats to human health, these dangers are often overlooked. In a previous study, we discovered that NEOs and OPEs can negatively impact development, but liver metabolism can help mitigate their harmful effects. In our current research, our objective was to investigate the toxicity mechanisms associated with NEOs, OPEs, and their liver metabolites using a human embryonic stem cell-based differentiation model that mimics early embryonic development. Our transcriptomics data revealed that NEOs and OPEs significantly influenced the expression of hundreds of genes, disrupted around 100 biological processes, and affected two signaling pathways. Notably, the BMP4 signaling pathway emerged as a key player in the disruption caused by exposure to these pollutants. Both NEOs and OPEs activated BMP4 signaling, potentially impacting early embryonic development. Interestingly, we observed that treatment with a human liver S9 fraction, which mimics liver metabolism, effectively reduced the toxic effects of these pollutants. Most importantly, it reversed the adverse effects dependent on the BMP4 pathway. These findings suggest that normal liver function plays a crucial role in detoxifying environmental pollutants and provides valuable experimental insights for addressing this issue.

Molecular Docking Analysis at the Human α7-nAChR and Proliferative and Evoked-Calcium Changes in SH-SY5Y Cells by Imidacloprid and Acetamiprid Insecticides

Acetamiprid (ACE) and Imidacloprid (IMI) are widely-used neonicotinoid insecticides (NNIs) with functional activity at human acetylcholine nicotinic receptors and, therefore, with putative toxic effects. The objective of this study was the evaluation of the interactions between NNIs and α7-nAChR, as this receptor keeps intracellular Ca2+ ([Ca2+]i) to an optimum for an adequate neuronal functioning. Possible interactions between NNIs and the cryo-EM structure of the human α-7 nAChR were identified by molecular docking. Additionally, NNI effects were analyzed in neuroblastoma SH-SY5Y cells, as they naturally express α-7 nAChRs. Functional studies included proliferative/cytotoxic effects (MTT test) in undifferentiated SH-SY-5Y cells and indirect measurements of [Ca2+]i transients in retinoic acid-differentiated SH-SY-5Y cells loaded with Fluo-4 AM. Docking analysis showed that the binding of IMI and ACE occurred at the same aromatic cage that the specific α-7 nAChR agonist EVP-6124. IMI showed a better docking strength than ACE. According to the MTT assays, low doses (10-50 µM) of IMI better than ACE stimulated neuroblastoma cell proliferation. At higher doses (250-500 µM), IMI also prevailed over ACE and dose-dependently triggered more abrupt fluorescence changes due to [Ca2+]i mobilization in differentiated SH-SY5Y neurons. Indeed, only IMI blunted nicotine-evoked intracellular fluorescence stimulation (i.e., nicotine cross-desensitization). Summarizing, IMI demonstrated a superior docking strength and more robust cellular responses compared to ACE, which were likely associated with a stronger activity at α-7nAChRs. Through the interaction with α-7nAChRs, IMI would demonstrate its high neurotoxic potential for humans. More research is needed for investigating the proliferative effects of IMI in neuroblastoma cells.

Source and health risk of urinary neonicotinoids in Tibetan pregnant women

High altitude could influence the level of exposure to neonicotinoids, but relevant data remain limited for people living in Tibet. We investigated 476 Tibetan pregnant women from Lhasa of Tibet, China in 2021 and measured eight neonicotinoids and four metabolites in urine. Food consumption was investigated by a food frequency questionnaire. Health risk was assessed by using hazard quotient (HQ) and hazard index (HI) based on acceptable daily dose or chronic reference dose. Neonicotinoids and metabolites were overall detected in 56.5% of urine samples with a median concentration being 0.73 μg g-1 creatinine. Four neonicotinoids or metabolites were detected in more than 10% of urine samples, including N-desmethyl-acetamiprid (47.5%), clothianidin (15.5%), thiamethoxam (16.0%), and imidacloprid (10.5%). Annual household income, family smoking, and pre-pregnancy body mass index were associated with the detection frequencies of neonicotinoids. Pregnant women with a higher consumption frequency of wheat, rice, fresh vegetable, fresh fruit, beef and mutton, fresh milk, yoghourt, candy and chocolate, or carbonated drinks had a higher detection frequency of neonicotinoids. Both HQ and HI were less than one. There was an evident exposure to neonicotinoids in Tibetan pregnant women with both plant- and animal-derived food items as exposure sources, but a low health risk was found based on current safety thresholds.

An updated status of currently used pesticides in India: Human dietary exposure from an Indian food basket

Currently used pesticides (CUPs) were introduced to have lower persistence and bioaccumulation, and lesser bioavailability towards non-target species. Nevertheless, CUPs still represent a concern for both human health and the environment. India is an important agricultural country experiencing a conversion from the use of obsolete organochlorine pesticides to a newer generation of phytosanitary products. As for other developing countries, very little is known about the transfer of CUPs to the human diet in India, where systematic monitoring is not in place. In this study, we analyzed ninety four CUPs and detected thirty CUPs in several food products belonging to five types: cereals and pulses, vegetables, fruits, animal-based foods, and water. Samples were taken from markets in Delhi (aggregating food produced all over India) and in the periurban area of Dehradun (northern India) (representing food produced locally and through more traditional practices). Overall, chlorpyrifos and chlorpropham were the most detected CUPs with a detection frequency of 33% and 25%, respectively. Except for vegetables and fruits, the levels of CUPs in all other food types were significantly higher in samples from Delhi (p < 0.05). Exposure dosage of CUPs through different food matrices was calculated, and chlorpropham detected in potatoes had the maximum exposure dosage to humans (2.46 × 10-6 mg/kg/day). Risk analysis based on the hazard quotient technique indicated that chlorpyrifos in rice (2.76 × 10-2) can be a concern.

Urinary neonicotinoids and metabolites are associated with obesity risk in Chinese school children

BACKGROUND

Neonicotinoids are the most widely used insecticides. Laboratory studies have suggested that neonicotinoids are one potential obesogen, but relevant data are limited in human.

OBJECTIVE

To examine the association between exposure to neonicotinoids and childhood obesity.

METHODS

We investigated 442 children in Shanghai, East China and measured eight neonicotinoids (thiamethoxam, clothianidin, acetamiprid, imidacloprid, thiacloprid, nitenpyram, dinotefuran, and imidaclothiz) and four metabolites (N-desmethyl-thiamethoxam, N-desmethyl-clothianidin, N-desmethyl-acetamiprid, and 5-OH-imidacloprid) in urine. Body mass index (BMI) and waist circumference (WC) were used to identify general overweight/obesity and central obesity, respectively. Linear and logistic regression models based on generalized estimating equations were used to investigate the associations of urinary neonicotinoids and metabolites with BMI z-score, WC z-score, general overweight/obesity, and central obesity.

RESULTS

Children with a positive detection of clothianidin and its metabolite had a marginally higher BMI z-score (regression coefficient (β): 0.08, 95% confidence interval (95% CI): 0.01, 0.14) after adjusted for relevant covariates. After creatinine-adjusted concentration was trichotomized, compared to children with a negative detection, children in the high urinary concentration of acetamiprid and its metabolite had a low BMI z-score (β: -0.19, 95%CI: -0.30, -0.08), children in the medium urinary concentration of neonicotinoids and metabolites other than thiamethoxam, clothianidin, acetamiprid, and their metabolites had a marginally higher BMI z-score (β: 0.25, 95%CI: 0.03, 0.46), a higher WC z-score (β: 0.24, 95%CI: 0.14, 0.33), and a higher odds of central obesity (odds ratio (OR): 2.16, 95% CI: 1.28, 3.63), and children in the medium urinary concentration of all neonicotinoids and metabolites had a higher odds of central obesity (OR: 1.55, 95%CI: 1.04, 2.33). Some associations showed sex- and age- related differences.

CONCLUSION

Urinary neonicotinoids and metabolites were found to be differently associated with obesity-related indexes, which suggested that exposure to neonicotinoids might have a mixed effect on childhood obesity.

Waterborne Tebuconazole Exposure Induces Male-Biased Sex Differentiation in Zebrafish (Danio rerio) Larvae via Aromatase Inhibition

Tebuconazole is a widely used fungicide for various crops that targets sterol 14-α-demethylase (CYP51) in fungi. However, attention has shifted to aromatase (CYP19) due to limited research indicating its reproductive impact on aquatic organisms. Herein, zebrafish were exposed to 0.5 mg/L tebuconazole at different developmental stages. The proportion of males increased significantly after long-term exposure during the sex differentiation phase (0-60, 5-60, and 19-60 days postfertilization (dpf)). Testosterone levels increased and 17β-estradiol and cyp19a1a expression levels decreased during the 5-60 dpf exposure, while the sex ratio was equally distributed on coexposure with 50 ng/L 17β-estradiol. Chemically activated luciferase gene expression bioassays determined that the male-biased sex differentiation was not caused by tebuconazole directly binding to sex hormone receptors. Protein expression and phosphorylation levels were specifically altered in the vascular endothelial growth factor signaling pathway despite excluding the possibility of tebuconazole directly interacting with kinases. Aromatase was selected for potential target analysis. Molecular docking and aromatase activity assays demonstrated the interactions between tebuconazole and aromatase, highlighting that tebuconazole poses a threat to fish populations by inducing a gender imbalance.

Characterization of Environmental Levels of Pesticide Residues in Household Air and Dust Samples near a Bioenergy Plant Using Treated Seed as Feedstock

Exposure to neonicotinoid insecticides is associated with adverse human health outcomes. There is environmental contamination in Saunders County, Nebraska, due to the accumulation of fungicides and insecticides from a now-closed ethanol plant using seed corn as stock. A pilot study quantified environmental contamination in nearby houses from residual pesticides by measuring dust and air (indoor/outdoor) concentrations of neonicotinoids and fungicides at the study site (households within two miles of the plant) and control towns (20-30 miles away). Air (SASS® 2300 Wetted-Wall Air Sampler) and surface dust (GHOST wipes with 4 × 4-inch template) samples were collected from eleven study households and six controls. Targeted analysis quantified 13 neonicotinoids, their transformation products and seven fungicides. Sample extracts were concentrated using solid phase extraction (SPE) cartridges, eluted with methanol and evaporated. Residues were re-dissolved in methanol-water (1:4) prior to analysis, with an Acquity H-Class ultraperformance liquid chromatograph (UPLC) and a Xevo triple quadrupole mass spectrometer. We compared differences across chemicals in air and surface dust samples at the study and control sites by dichotomizing concentrations above or below the detection limit, using Fisher's exact test. A relatively higher detection frequency was observed for clothianidin and thiamethoxam at the study site for the surface dust samples, similarly for thiamethoxam in the air samples. Our results suggest airborne contamination (neonicotinoids and fungicides) from the ethanol facility at houses near the pesticide contamination.

Proteomic responses in the human dopaminergic LUHMES cell line to imidacloprid and its metabolites imidacloprid-olefin and desnitro-imidacloprid

Neonicotinoids (neonics) are amongst the most commonly used class of pesticides globally. In the United States, imidacloprid (IMI) is extensively used for agriculture and in other common applications such as house-hold pest control. Regular exposure to IMI, and several of its known metabolites including IMI-olefin and desnitro-imidacloprid (DN-IMI), has been shown to be harmful to many organisms including mammals, birds, and fish. Studies show that neonics bind human nicotinicacetylcholine receptors (nAChRs) and cause cellular toxicity. In the dopaminergic Lund human mesencephalic (LUHMES) cell line, IMI and other neonics (10-100 μM) have been recently shown to activate intracellular calcium signaling through nAChRs. Thus, we examined proteomic responses of LUHMES cells to a 48-h treatment with 50 μM IMI, IMI-olefin, or DN-IMI. Our findings show differential effects of these neonics on cellular protein expression. Bioinformatic analysis of significantly altered proteins indicates an effect of IMI, IMI-olefin, and DN-IMI on protein synthesis and ribosomal function. These findings suggest a role for protein synthesis and transcriptional regulation in neonic-mediated dopaminergic neurotoxicity.

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.

Urinary neonicotinoid insecticides and adiposity measures among 7-year-old children in northern China: A cross-sectional study

BACKGROUND

Neonicotinoid insecticides (NEOs) are emerging synthetic insecticides used in various pest management regimens worldwide. Toxicology studies have indicated the obesogenic potential of NEOs, but their associations with adiposity measures are largely unknown.

OBJECTIVES

We aimed to assess urinary levels of NEOs/metabolites and their associations with children's adiposity measures, and to further investigate the potential role of oxidative stress.

METHODS

This study included 380 children who participated in the 7th year's follow-up of the Laizhou Wan Birth Cohort in northern China. Urinary levels of seven NEOs and two metabolites and a biomarker of lipid peroxidation named 8-iso-prostaglandin-F2α (8-iso-PGF2α) were detected. A total of nine indicators of adiposity were measured. Body mass index (BMI) z-score ≥85th percentile was defined as overweight/obesity, and waist-to-height ratio (WHtR) ≥0.5 was considered as abdominal obesity. Multiple linear regression, binary logistic regression and mediation analysis were performed.

RESULTS

Six NEOs [imidacloprid (IMI, 99.7%), clothianidin (CLO, 98.9%), dinotefuran (DIN, 97.6%), thiamethoxam (THM, 95.5%), acetamiprid (ACE, 82.9%), thiacloprid (THD, 77.6%)] and two metabolites [N-desmethyl-acetamiprid (N-DMA, 100.0%), 6-chloronicotinic acid (6-CINA, 97.9%)] exhibited high detection rates. Multiple linear regressions showed positive associations of waist circumference with urinary levels of IMI and THM, of WHtR with IMI and THM levels, and of body fat percentage with 6-CINA levels. In contrast, exposure to N-DMA was negatively associated with body fat percentage and fat mass index. Binary logistic regressions further revealed that higher IMI levels were associated with overweight/obesity (OR = 1.556, 95% CI: 1.100, 2.201) and abdominal obesity (OR = 1.478, 95% CI: 1.078, 2.026) in children. 8-iso-PGF2α demonstrated 27.92%, 69.52% and 35.37% mediating effects in the positive associations of IMI, THD and THM with WHtR, respectively. Sex modified the associations of DIN with body fat mass (p_int = 0.032), body fat percentage (p_int = 0.009), fat mass index (p_int = 0.037) and the overweight/obesity rate (p_int = 0.046), with negative associations in girls and nonsignificant positive associations in boys.

CONCLUSIONS

School-age children in northern China were widely exposed to NEOs/metabolites. Urinary levels of NEOs/metabolites were associated with adiposity measures through the mediating role of 8-iso-PGF2α. These associations were mixed, and a sex-specific effect might exist.

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.

Monitoring residues of pesticides in food in Brazil: A multiscale analysis of the main contaminants, dietary cancer risk estimative and mechanisms associated

Introduction

Pesticides pose a risk for cancer development and progression. People are continuously exposed to such substances by several routes, including daily intake of contaminated food and water, especially in countries that are highly pesticide consumers and have very permissive legislation about pesticide contamination as Brazil. This work investigated the relationship among pesticides, food contamination, and dietary cancer risk.

Methods

Analyzed two social reports from the Brazilian Government: the Program for Analysis of Residues of Pesticides in Food (PARA) and The National Program for Control of Waste and Contaminants (PNCRC).

Results and discussion

First, we characterized the main pesticide residues detected over the maximum limits allowed by legislation or those prohibited for use in food samples analyzed across the country. Based on this list, we estimated the dietary cancer risks for some of the selected pesticides. Finally, we searched for data about dietary cancer risks and carcinogenic mechanisms of each pesticide. We also provided a critical analysis concerning the pesticide scenario in Brazil, aiming to discuss the food contamination levels observed from a geographical, political, and public health perspective. Exposures to pesticides in Brazil violate a range of human rights when food and water for human consumption are contaminated.

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.

Cheminformatics analysis of chemicals that increase estrogen and progesterone synthesis for a breast cancer hazard assessment

Factors that increase estrogen or progesterone (P4) action are well-established as increasing breast cancer risk, and many first-line treatments to prevent breast cancer recurrence work by blocking estrogen synthesis or action. In previous work, using data from an in vitro steroidogenesis assay developed for the U.S. Environmental Protection Agency (EPA) ToxCast program, we identified 182 chemicals that increased estradiol (E2up) and 185 that increased progesterone (P4up) in human H295R adrenocortical carcinoma cells, an OECD validated assay for steroidogenesis. Chemicals known to induce mammary effects in vivo were very likely to increase E2 or P4 synthesis, further supporting the importance of these pathways for breast cancer. To identify additional chemical exposures that may increase breast cancer risk through E2 or P4 steroidogenesis, we developed a cheminformatics approach to identify structural features associated with these activities and to predict other E2 or P4 steroidogens from their chemical structures. First, we used molecular descriptors and physicochemical properties to cluster the 2,012 chemicals screened in the steroidogenesis assay using a self-organizing map (SOM). Structural features such as triazine, phenol, or more broadly benzene ramified with halide, amine or alcohol, are enriched for E2 or P4up chemicals. Among E2up chemicals, phenol and benzenone are found as significant substructures, along with nitrogen-containing biphenyls. For P4up chemicals, phenol and complex aromatic systems ramified with oxygen-based groups such as flavone or phenolphthalein are significant substructures. Chemicals that are active for both E2up and P4up are enriched with substructures such as dihydroxy phosphanedithione or are small chemicals that contain one benzene ramified with chlorine, alcohol, methyl or primary amine. These results are confirmed with a chemotype ToxPrint analysis. Then, we used machine learning and artificial intelligence algorithms to develop and validate predictive classification QSAR models for E2up and P4up chemicals. These models gave reasonable external prediction performances (balanced accuracy ~ 0.8 and Matthews Coefficient Correlation ~ 0.5) on an external validation. The QSAR models were enriched by adding a confidence score that considers the chemical applicability domain and a ToxPrint assessment of the chemical. This profiling and these models may be useful to direct future testing and risk assessments for chemicals related to breast cancer and other hormonally-mediated outcomes.

Neonicotinoids residues in the honey circulating in Chinese market and health risk on honey bees and human

China is the largest beekeeping and honey consumption country globally. Neonicotinoids in honey can pose adverse effects on honey bees and human, but data on neonicotinoids residues in honey and its health risk remain limited in China. A total of 94 honey samples were selected from Chinese market based on production region and sale volume in 2020. Eight neonicotinoids and four metabolites were determined by liquid chromatography coupled to mass spectrometry. Health risk of neonicotinoids in honey on honey bees and human was assessed by hazard quotient (HQ) and hazard index (HI). Neonicotinoids and their metabolites were overall detected in 97.9% of honey samples. Acetamiprid, thiamethoxam, and imidacloprid were top three dominant neonicotinoids in honey with the detection frequencies of 92.6%, 90.4%, and 73.4%, respectively. For honey bees, 78.7% of honey samples had a HI larger than one based on the safety threshold value of sublethal effects. Top three neonicotinoids with the highest percent proportion of HQ larger than one for honey bees were acetamiprid (43.6%), imidacloprid (31.9%), and thiamethoxam (24.5%) and their maximum HQs were 420, 210, and 41, respectively. Based on oral median lethal doses for honey bees, both HQ and HI were lower than one in all honey samples. For human, both HQ and HI were lower than one based on acceptable daily intakes in all honey samples. Neonicotinoids concentrations and detection frequencies in honey samples and its health risk varied with production region, commercial value of nectariferous plants, number of nectariferous plants, and sale price. The results suggested extensive residues of neonicotinoids in honey in Chinese market with a variation by the characteristics of honey. The residues were likely to affect the health of honey bees, but showed no detectable effect on human health.

Molecularly Imprinted Polymer-Modified Microneedle Sensor for the Detection of Imidacloprid Pesticides in Food Samples

A portable, molecularly imprinted polymer (MIP)-based microneedle (MN) sensor for the electrochemical detection of imidacloprid (IDP) has been demonstrated. The MN sensor was fabricated via layer-by-layer (LbL) in-tube coating using a carbon nanotube (CNT)/cellulose nanocrystal (CNC) composite, and an IDP-imprinted polyaniline layer co-polymerized with imidazole-functionalized CNCs (PANI-co-CNC-Im) as the biomimetic receptor film. The sensor, termed MIP@CNT/CNC MN, was analyzed using both cyclic voltammetry (CV) and differential pulse voltammetry (DPV) and showed excellent electrochemical performance for the detection of IDP. The CV detection range for IDP was 2.0-99 µM, with limits of detection (LOD) of 0.35 µM, while the DPV detection range was 0.20-92 µM with an LOD of 0.06 µM. Additionally, the MIP@CNT/CNC MN sensor showed excellent reusability and could be used up to nine times with a 1.4 % relative standard deviation (% RSD) between uses. Lastly, the MIP@CNT/CNC MN sensor successfully demonstrated the quantification of IDP in a honey sample.

Long-Term Exposure to Neonicotinoid Insecticide Acetamiprid at Environmentally Relevant Concentrations Impairs Endocrine Functions in Zebrafish: Bioaccumulation, Feminization, and Transgenerational Effects

Neonicotinoid insecticides have attracted worldwide attention due to their ubiquitous occurrence and detrimental effects on aquatic organisms, yet their impacts on fish reproduction during long-term exposure remain unknown. Here, zebrafish (F0) were exposed to a neonicotinoid, acetamiprid, at 0.19-1637 μg/L for 154 d. Accumulation and biotransformation of acetamiprid were observed in adult fish, and the parent compound and its metabolite (acetamiprid-N-desmethyl) were transferred to their offspring. Acetamiprid caused slight survival reduction and significant feminization in F0 fish even at the lowest concentration. Hormone levels in F0 fish were remarkedly altered, that is, gonad 17β-estradiol (E2) significantly increased, while androstenedione decreased. The corresponding transcription of steroidogenic genes (ar, cyp19b, fshβ, gnrh2, gnrh3, and lhβ) were significantly upregulated in the brain and gonad of the females but downregulated in the males. The vtg1 gene expression in the liver of male fish was also upregulated. In addition to F0 fish, parental exposure to acetamiprid decreased hatchability and enhanced malformation of F1 embryos. Chronic exposure to acetamiprid at environmentally relevant concentrations altered hormone production and the related gene expression of the hypothalamic-pituitary-gonad (HPG) axis in a sex-dependent way, caused feminization and reproductive dysfunction in zebrafish, and impaired production and development of their offspring.

Current status of pesticide effects on environment, human health and it's eco-friendly management as bioremediation: A comprehensive review

Pesticides are either natural or chemically synthesized compounds that are used to control a variety of pests. These chemical compounds are used in a variety of sectors like food, forestry, agriculture and aquaculture. Pesticides shows their toxicity into the living systems. The World Health Organization (WHO) categorizes them based on their detrimental effects, emphasizing the relevance of public health. The usage can be minimized to a least level by using them sparingly with a complete grasp of their categorization, which is beneficial to both human health and the environment. In this review, we have discussed pesticides with respect to their global scenarios, such as worldwide distribution and environmental impacts. Major literature focused on potential uses of pesticides, classification according to their properties and toxicity and their adverse effect on natural system (soil and aquatic), water, plants (growth, metabolism, genotypic and phenotypic changes and impact on plants defense system), human health (genetic alteration, cancer, allergies, and asthma), and preserve food products. We have also described eco-friendly management strategies for pesticides as a green solution, including bacterial degradation, myco-remediation, phytoremediation, and microalgae-based bioremediation. The microbes, using catabolic enzymes for degradation of pesticides and clean-up from the environment. This review shows the importance of finding potent microbes, novel genes, and biotechnological applications for pesticide waste management to create a sustainable environment.

Comparative study of neonicotinoid insecticides (NNIs) and NNI-Related substances (r-NNIs) in foodstuffs and indoor dust

Comparative studies of neonicotinoid insecticides (NNIs) and NNI-related substances (r-NNIs) in foodstuffs and indoor dust are rare. Herein, we investigated the feature fragmentations of nine NNIs in high-energy collision dissociation cells via high-resolution orbitrap mass spectrometry and observed that NNIs can consistently generate several feature fragments (e.g., C6H5NCl+, C4H3NSCl+, and C6H5NF3+). Consequently, NNIs and r-NNIs were comprehensively (targeted, suspect, and feature fragment-dependent) detected in 107 foodstuff and 49 indoor dust samples collected from Nanjing City (eastern China). We fully or tentatively identified 9 target NNIs and 5 r-NNIs in these samples. NNIs and r-NNIs were detected in 93.5% of the analyzed foodstuff samples, and high concentrations were detected in vegetables (mean: 409 ng/g wet weight [ww]) and fruits (127 ng/g ww). Regarding indoor dust, imidacloprid and acetamiprid exhibited extremely high detection frequencies and contamination levels, and the highest mean concentrations of NNIs and r-NNIs were detected in dormitory samples. Based on the NNI and r-NNI concentrations in the analyzed samples, the mean estimated daily intake values for Chinese adults and children via dietary intake and dust ingestion were 2080-8190 ng/kg bw/day and 378-2680 pg/kg bw/day, respectively.

Detection and Concentration of Neonicotinoids and Other Pesticides in Honey from Honey Bee Colonies Located in Regions That Differ in Agricultural Practices: Implications for Human and Bee Health

This is a preliminary study conducted to analyze the presence and concentration of pesticides in honey obtained from honey bee colonies located in two regions with managed ecosystems that differ in the intensity and technification of agricultural practices. Fourteen pesticides at variable concentrations were detected in 63% of the samples analyzed. The pesticides most frequently found at higher concentrations were insecticides (neonicotinoids, followed by organophosphates), herbicides, and fungicides. The number, frequency, and concentration of pesticides were higher in samples collected from hives located where intensive and highly-technified agriculture is practiced. Forty-three percent of the samples from that zone had residues of imidacloprid, compared with only 13% of the samples from the less-technified zone. Furthermore, 87.5% of those samples had imidacloprid concentrations that were above sublethal doses for honey bees (>0.25 ng/g) but that are not considered hazardous to human health by the European Commission. The results of this study suggest that honey can be used as a bioindicator of environmental contamination by pesticides, which highlights the need to continue monitoring contaminants in this product to determine the risks of pesticide impacts on pollinator health, on ecosystems, and on their potential implications to human health and other non-target organisms.

Long-Term Effects of Imidacloprid, Thiacloprid, and Clothianidin on the Growth and Development of Eisenia andrei

Recently, the high toxicity of neonicotinoids to the survival and reproduction of adult earthworms has become apparent in standard 56-day toxicity tests. The persistence of some neonicotinoids and/or their repeated application may lead to long-term exposure, possibly also affecting other parts of the life cycle of earthworms. The present study aimed at providing insight into the sublethal effects of imidacloprid, thiacloprid, and clothianidin on juvenile Eisenia andrei exposed for 16 weeks in Lufa 2.2 soil. Significant effects on growth and maturation were observed for all compounds. Exposure to 0.125 mg imidacloprid/kg dry soil and 0.03125 and 0.0625 mg thiacloprid/kg dry soil significantly affected the growth of the earthworms, while significant maturation effects were observed at 0.03125 mg/kg dry soil for imidacloprid and thiacloprid and 0.25 mg clothianidin/kg dry soil. The 16-week no-observed-effect concentrations (NOECs) found in the present study were lower than previously reported NOECs for effects on earthworm reproduction. Predicted environmental concentrations after a single application exceeded the observed NOECs for effects on earthworm maturation in the case of imidacloprid and thiacloprid and for effects on earthworm growth in the case of thiacloprid and clothianidin. Environ Toxicol Chem 2022;41:1686-1695. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Investigating children's chemical exposome - Description and possible determinants of exposure in the region of Luxembourg based on hair analysis

The specific physiology and behaviour of children makes them particularly vulnerable to chemical exposure. Specific studies must therefore be conducted to understand the impact of pollution on children's health. Human biomonitoring is a reliable approach for exposure assessment, and hair, allowing the detection of parent chemicals and metabolites, and covering wider time windows than urine and blood is particularly adapted to study chronic exposure. The present study aims at assessing chemical exposure and investigating possible determinants of exposure in children living in Luxembourg. Hair samples were collected from 256 children below 13 y/o and tested for 153 compounds (140 pesticides, 4 PCBs, 7 BDEs and 2 bisphenols). Moreover, anthropometric parameters, information on diet, residence, and presence of pets at home was collected through questionnaires. Correlations, regressions, t-tests, PLS-DA and MANOVAs, were used to investigate exposure patterns. Twenty-nine to 88 (median = 61) compounds were detected per sample. The highest median concentration was observed for BPA (133.6 pg/mg). Twenty-three biomarkers were detected in ≥ 95% of the samples, including 13 in all samples (11 pesticides, BPA and BPS). Exposure was higher at younger ages (R² = 0.57), and boys were more exposed to non-persistent pesticides than girls. Presence of persistent organic pollutants in most children suggests that exposure is still ongoing. Moreover, diet (e.g. imazalil: 0.33 pg/mg in organic, 1.15 pg/mg in conventional, p-value < 0.001), residence area (e.g. imidacloprid: 0.29 pg/mg in urban, 0.47 pg/mg in countryside, p-value = 0.03), and having pets (e.g. fipronil: 0.32 pg/mg in pets, 0.09 pg/mg in no pets, p-value < 0.001) were identified as determinants of exposure. The present study demonstrates that children are simultaneously exposed to multiple pollutants from different chemical classes, and confirms the suitability of hair to investigate exposure. These results set the basis for further investigations to better understand the determinants of chemical exposure in children.

High spatial resolved cropland coverage and cultivation category determine neonicotinoid distribution in agricultural soil at the provincial scale

Croplands are experiencing increasing neonicotinoid pollution and ecological health problems, which are especially widely applied in China. However, the large regional scale distribution of neonicotinoids and the key factors have seldom been determined. We show that the total residual concentration of neonicotinoids ranged from 13.4 to 157 ng/g with an average level of 75.8 ng/g and imidacloprid which was the dominant compound ranged from 10.4 to 81.3 ng/g during 2017-2021 in the Yangtze River Delta, China. In comparison, the neonicotinoid residues detected here were mostly higher than those in other regions. We further show that the 1-km spatial resolution cropland coverage (78.0%) and crop type (18.1%) predominantly contributed to the large spatial variation of neonicotinoids after adjusting for the factors including temperature, soil pH, soil moisture, and precipitation via automatic linear regression modeling at the provincial scale. Additional analyses revealed that tea croplands had significantly lowest concentration and fruit fields had the highest level due to the different application methods. Our findings provide new insight into key factors quantifying the high spatial resolved distribution of neonicotinoids and urgently call for reasonable application methods against rapidly growing ecology threats from neonicotinoid pollution in China.

Exposure assessment of neonicotinoid insecticides and their metabolites in Chinese women during pregnancy: A longitudinal study

Neonicotinoid insecticides (NNIs) are the most widely used insecticides globally and ubiquitous in the environment, which has led to widespread human exposure. However, studies on internal exposure levels of NNIs and their metabolites in pregnant women are scarce. In this study, we measured nine parent NNIs and ten main metabolites in 1224 urine samples donated by 408 pregnant women at three trimesters. In the urine samples, the unadjusted vs. specific gravity (SG) adjusted median concentrations and detection frequencies (DFs) of desmethyl-acetamiprid (DM-ACE; 1.01 vs. 1.08 ng/mL; DF: 99.7%), 5-hydroxy-imidacloprid (5-hydroxy-IMI; 0.54 vs. 0.56 ng/mL; 98.5%), imidacloprid-olefin (IMI-olefin; 0.41 vs. 0.44 ng/mL; 99.3%), and desnitro-imidacloprid (DN-IMI; 0.12 vs. 0.12 ng/mL; 90.4%) were higher than their corresponding parent NNIs, acetamiprid (ACE; <0.01 vs. <0.01 ng/mL; 26.4%) and imidacloprid (IMI; 0.04 vs. 0.04 ng/mL; 69.9%). The unadjusted and SG-adjusted median concentrations of clothianidin (CLO), thiamethoxam (THM), and desmethyl-clothianidin (DM-CLO) were 0.05 vs. 0.07, 0.05 vs. 0.06, and 0.04 vs. 0.05 ng/mL, with the DFs of 61.0%, 57.5%, and 75.7%, respectively. The cumulative exposure level, imidacloprid-equivalent total NNIs (IMI_eq), was generated by the relative potency factor approach considering the toxic effects of NNIs and their metabolites. The unadjusted IMI_eq varied from 0.17 ng/mL (SG-adjusted: 0.20) to 1969 ng/mL (SG-adjusted: 1817) with a median of 14.1 ng/mL (SG-adjusted: 14.1). A decreased trend was observed in urinary NNIs and their metabolites throughout the three trimesters. Maternal age, educational level, and household income were related to the concentrations of NNIs and their metabolites. DM-ACE, 5-hydroxy-IMI, and IMI-olefin were significantly lower in winter than in autumn; DN-IMI, THM, CLO, and DM-CLO were significantly higher in both summer and autumn than in winter. The maximum estimated daily intake of IMI_eq [34.8 μg/kg-body weight (bw)/d] was lower than the chronic reference dose of IMI (57 μg/kg-bw/d) currently recommended by the United States Environmental Protection Agency. Human health risk of exposure to NNIs and their main metabolites warranted further studies.

Towards regulation of Endocrine Disrupting chemicals (EDCs) in water resources using bioassays - A guide to developing a testing strategy

Endocrine disrupting chemicals (EDCs) are found in every environmental medium and are chemically diverse. Their presence in water resources can negatively impact the health of both human and wildlife. Currently, there are no mandatory screening mandates or regulations for EDC levels in complex water samples globally. Bioassays, which allow quantifying in vivo or in vitro biological effects of chemicals are used commonly to assess acute toxicity in water. The existing OECD framework to identify single-compound EDCs offers a set of bioassays that are validated for the Estrogen-, Androgen-, and Thyroid hormones, and for Steroidogenesis pathways (EATS). In this review, we discussed bioassays that could be potentially used to screen EDCs in water resources, including in vivo and in vitro bioassays using invertebrates, fish, amphibians, and/or mammalians species. Strengths and weaknesses of samples preparation for complex water samples are discussed. We also review how to calculate the Effect-Based Trigger values, which could serve as thresholds to determine if a given water sample poses a risk based on existing quality standards. This work aims to assist governments and regulatory agencies in developing a testing strategy towards regulation of EDCs in water resources worldwide. The main recommendations include 1) opting for internationally validated cell reporter in vitro bioassays to reduce animal use & cost; 2) testing for cell viability (a critical parameter) when using in vitro bioassays; and 3) evaluating the recovery of the water sample preparation method selected. This review also highlights future research avenues for the EDC screening revolution (e.g., 3D tissue culture, transgenic animals, OMICs, and Adverse Outcome Pathways (AOPs)).

Neonicotinoid insecticide metabolites in seminal plasma: Associations with semen quality

Animal studies have revealed that exposure to neonicotinoid insecticides (NNIs) could compromise male reproductive function; however, related data on the occurrence of NNIs and their specific metabolites in human seminal plasma are scarce. To explore the potential effects of NNI exposure on male semen quality, we determined the concentrations of NNIs and some of their metabolites (collectively defined as mNNIs) in seminal plasma samples collected from men (n = 191) who visited a fertility clinic in Shijiazhuang, North China from 2018 to 2019. Associations between the mNNI concentrations and semen quality parameters were assessed using linear regression models, adjusting for important covariates. In the seminal plasma samples, desmethyl-acetamiprid (DM-ACE, detection frequency: 98.4%), imidacloprid-olefin (IMI-olefin, detection frequency: 86.5%), and desmethyl-clothianidin (DM-CLO, detection frequency: 70.8%) were frequently detected at median concentrations of 0.052, 0.003, and 0.007 ng/mL, respectively; meanwhile other compounds were detected at less than the method detection limits. In the single-mNNI models, the IMI-olefin concentration was associated with decreased progressive motility [IMI-olefin concentration: percent change (%Δ) = -17.0; 95% confidence interval (CI) = -30.3, -0.92; the highest tertile compared with the lowest tertile: %Δ = -21.1; 95% CI = -37.5, -0.23]. Similar results were found in the multiple-mNNIs models. No other inverse associations were found between the other mNNI concentrations and semen quality parameters. This is the first study to identify the occurrence of mNNIs in the seminal plasma and the potential associations of their concentrations with human semen quality parameters. These findings imply an inverse association between the IMI-olefin concentration and semen quality.

Microbial Technologies Employed for Biodegradation of Neonicotinoids in the Agroecosystem

Neonicotinoids are synthetic pesticides widely used for the control of various pests in agriculture throughout the world. They mainly attack the nicotinic acetylcholine receptors, generate nervous stimulation, receptor clot, paralysis and finally cause death. They are low volatile, highly soluble and have a long half-life in soil and water. Due to their extensive use, the environmental residues have immensely increased in the last two decades and caused many hazardous effects on non-target organisms, including humans. Hence, for the protection of the environment and diversity of living organism's the degradation of neonicotinoids has received widespread attention. Compared to the other methods, biological methods are considered cost-effective, eco-friendly and most efficient. In particular, the use of microbial species makes the degradation of xenobiotics more accessible fast and active due to their smaller size. Since this degradation also converts xenobiotics into less toxic substances, the various metabolic pathways for the microbial degradation of neonicotinoids have been systematically discussed. Additionally, different enzymes, genes, plasmids and proteins are also investigated here. At last, this review highlights the implementation of innovative tools, databases, multi-omics strategies and immobilization techniques of microbial cells to detect and degrade neonicotinoids in the environment.

Organochlorine pesticide dieldrin upregulate proximal promoter (PII) driven CYP19A1 gene expression and increases estrogen production in granulosa cells

Organochlorine pesticides are highly persistent environmental pollutants, generally shown to act through estrogen receptor alpha and alter estrogen biosynthesis. However, the molecular mechanism of regulation of estrogen biosynthesis by these pesticides is not clear. Estrogen is main female fertility hormone regulated by rate-limiting enzyme aromatase. It is encoded by the CYP19A1 gene, which is expressed using specific promoters. In the present study, the attempt has been made to elucidate the effect of dieldrin on the promoter-specific CYP19A1 gene expression and estrogen hormone production in buffalo granulosa cells. The buffalo granulosa cells were cultured and treated with dieldrin in a dose (100,150 and 200 ng/mL) and time (6, 12, and 24 h) dependent manner, followed by analysis of CYP19A1, promoter-specific CYP19A1 transcript expression, and estrogen production. Results showed that dieldrin significantly increased the expression of the CYP19A1 gene after 6 and 12 h while its expression was decreased after 24 h. To understand the upregulation of CYP19A1 gene, promoters' specific CYP19A1 transcript analysis was done. The finding showed that dieldrin significantly increased the proximal promoter specific CYP19A1 transcript while there was no effect on distal promoter specific CYP19A1 transcripts. This specific-promoter activity was quantified by chromatin immunoprecipitation assay (ChIP). Results confirmed the involvement of the proximal promoter in the overexpression of CYP19A1 gene. Furthermore, a significant increase in estradiol-17β level was also observed. Overall, the present study demonstrated the stimulatory effect of dieldrin on the CYP19A1 gene and will help to understand the toxicological role of dieldrin on the reproductive system.

Serum concentrations of neonicotinoids, and their associations with lipid molecules of the general residents in Wuxi City, Eastern China

Exposure to neonicotinoid insecticides (NNIs) was proven to be harmful to organisms, however, there is a dearth of information regarding their occurrence and adverse effects on the general residents. Here, n = 120 human serum samples were collected from the same area of Wuxi city, Eastern China, and these serum samples were further analyzed for nine NNIs and nine target lipid molecules by use of ultrahigh performance liquid chromatography-quadrupole orbitrap high-resolution mass spectrometer. We observed that four out of nine NNIs exhibited relatively high detection frequencies (DF), and these NNIs were imidacloprid (IMI; DF = 28.3%), clothianidin (CLO; 16.7%), thiacloprid (THI; 14.2%), and acetamiprid (ACE; 12.5%), respectively, with 95th concentrations ranging from 32.0 to 427 pg/mL. Median concentrations of imidacloprid-equivalent total neonicotinoids (IMI_eq) and ∑₇NNI were 46.6 pg/mL and 26 pg/mL, respectively. Five out of nine lipid molecules exhibited higher levels, that were docosahexaenoic acid [FA(22:6)], 18:0 phosphocholine [LysoPC(18:0)], 18:0 phosphoethanolamine [LysoPE(18:0)], D18:1-18:0 sphingomyelin [SM(d18:1/18:0)], and 18:1-18:1 diglycerol [DG(18:1/18:1)], respectively. More interestingly, we observed statistically significant correlations (student's t-test, one-way ANOVA, or Mann-Whitney test; p < 0.05) between NNI levels and population characteristics (i.e. age, smoking, and health status). Beyond that, we also observed statistically significant correlations between levels of selected NNIs (CLO, ACE, or THI) and lipid molecules [LysoPE(18:0), SM(d18:1/18:0), and DG(18:1/18:1)]. Collectively, for the first time, we provided the information on contamination levels of NNIs in serum samples of general residents in China and demonstrated the associations between concentrations of NNIs and levels of lipid molecular species.

Acute toxicity, accumulation and sublethal effects of four neonicotinoids on juvenile Black Tiger Shrimp (Penaeus monodon)

Neonicotinoid pesticides have been detected in aquatic habitats, and exposure may impact the health of aquatic organisms such as commercially-important crustaceans. Black Tiger Shrimp (Penaeus monodon) is a broadly distributed and high-value shrimp species that rely on estuaries for early life stages. Differences in the acute toxicity and accumulation of different neonicotinoids in tissues of commercial crustaceans have not been widely investigated. This study compared acute toxicity, uptake, and depuration of four neonicotinoids; thiamethoxam, clothianidin, acetamiprid, and imidacloprid, on juvenile P. monodon and their effects on enzyme biomarkers. Acute toxicity (48-h LC₅₀) was determined as 190 μg L^-1 (clothianidin), 390 μg L^-1 (thiamethoxam), 408 μg L^-1 (imidacloprid), and >500 μg L^-1(acetamiprid). To assess uptake and elimination, shrimp were exposed to a fixed 5 μg L^-1 water concentration for eight days (uptake) or four days of exposure followed by four days of depuration (elimination). Neonicotinoid water and tissue concentrations were measured by liquid chromatography-mass spectrometry following solid-phase extraction and QuEChER extraction respectively. The lower toxicity associated with acetamiprid could be associated with lower accumulation in the tissue, with concentrations remaining below 0.01 μg g^-1. The activity of acetylcholinesterase, catalase and glutathione S-transferase in abdominal tissues was determined by spectrophotometric assay, with significant sublethal effects detected for all four neonicotinoids. Depuration reduced the tissue concentration of the active ingredient and reduced the activity of oxidative stress enzymes. Given acetamiprid showed no acute toxicity and reduced impact on the enzymatic activity of P. monodon, it may be an appropriate alternative to other neonicotinoids in shrimp producing areas.

Pesticides: formulants, distribution pathways and effects on human health - a review

Pesticides are commonly used in agriculture to enhance crop production and control pests. Therefore, pesticide residues can persist in the environment and agricultural crops. Although modern formulations are relatively safe to non-target species, numerous theoretical and experimental data demonstrate that pesticide residues can produce long-term negative effects on the health of humans and animals and stability of ecosystems. Of particular interest are molecular mechanisms that mediate the start of a cascade of adverse effects. This is a review of the latest literature data on the effects and consequences of contamination of agricultural crops by pesticide residues. In addition, we address the issue of implicit risks associated with pesticide formulations. The effects of pesticides are considered in the context of the Adverse Outcome Pathway concept.

Measuring urinary concentrations of neonicotinoid insecticides by modified solid-phase extraction-ultrahigh performance liquid chromatography-tandem mass spectrometry: Application to human exposure and risk assessment

Neonicotinoid insecticides are the most widely used insecticides in the world. However, some experiments in vivo and vitro have shown association between neonicotinoids exposure and adverse effects in non-target mammals. The aims of this study were to 1) develop a robust method for simultaneous quantification of urinary neonicotinoids with a wide water solubility range by modified solid-phase extraction-ultrahigh performance liquid chromatography- tandem mass spectrometry and 2) quantify the concentrations of ten neonicotinoids in 386 adolescents in Chongqing of Southwest China by using the developed method and assess health risks of exposure to neonicotinoids. The introduction of extractive crystallization effectively removed interfering inorganic salts and improved the sensitivity of the method. The mean recoveries of all the analytes were satisfactory in the range of 89.1-104.8% and the limits of detection ranged from 0.001 to 0.02 ng/mL. The developed method was sensitive, accurate and suitable for trace detection and batch analysis in biomonitoring-based studies. Of the ten examined neonicotinoids, acetamiprid had the highest geometric mean concentration (49.43 μg/g creatinine), followed by clothianidin (5.01), imidacloprid (3.80), thiamethoxam (3.24), thiacloprid (2.25), nitenpyram (1.79), dinotefuran (1.76), sulfoxaflor (1.65), imidaclothiz (1.28) and flonicamid (1.01). High detection rates of neonicotinoids (79.3-100.0%) indicated a ubiquitous adolescents' exposure to neonicotinoids in urban areas of Chongqing. Nevertheless, hazard quotient and hazard index data exhibited a low health risk caused by the individual and cumulative exposure to neonicotinoids on the basis of the reference limit values recommended by the U.S. Environmental Protection Agency and the National Food Safety Standard of China.

Potential Environmental Health Risk Analysis of Neonicotinoids and a Synergist

The extensive use of neonicotinoid pesticides has led to their widespread presence in the environment, resulting in considerable safety risks to the ecosystem and human health. In this study, we investigated the biotransformation behavior of a cocktail of multiple neonicotinoids and piperonyl butoxide (PBO) synergist in vivo and their potential environmental health risk. It was found that neonicotinoids with a cyano group, such as acetamiprid and thiacloprid, tended to accumulate in liver and spleen tissues, while others with nitro groups (imidacloprid, thiamethoxam, clothianidin, dinotefuran, and nitenpyram) were mostly excreted in urine. In the presence of the synergist PBO, the metabolism of neonicotinoids in vivo changed, mainly through the nitro reduction pathway, while a low abundance of related metabolites was observed in the conventional hydroxylation and demethylation metabolic pathways, due to inhibition of CYP450 enzymes by the synergist. Furthermore, DNA methylation damage in vivo was exacerbated by the induction of hydroxylamine metabolites formed in the intermediate process of neonicotinoid metabolism with the synergistic effect of PBO, which resulted in a higher level of the O⁶-methyldeoxyguanosine (O⁶-medG) biomarker in the liver. Therefore, during the comprehensive evaluation of pesticide environmental risks, attention should be paid not only to the co-exposure mode under real environmental conditions but also to the potential risks of intermediate metabolism and related intermediate metabolites. This study provides a referential strategy and theoretical support for the health risk assessment of co-exposure of chemicals.

Partial Agonist Activity of Neonicotinoids on Rat Nicotinic Receptors: Consequences over Epinephrine Secretion and In Vivo Blood Pressure

Neonicotinoid insecticides are nicotine-derived molecules which exert acute neurotoxic effects over the insect central nervous system by activating nicotinic acetylcholine receptors (nAChRs). However, these receptors are also present in the mammalian central and peripheral nervous system, where the effects of neonicotinoids are faintly known. In mammals, cholinergic synapses are crucial for the control of vascular tone, blood pressure and skeletal muscle contraction. We therefore hypothesized that neonicotinoids could affect cholinergic networks in mammals and sought to highlight functional consequences of acute intoxication in rats with sub-lethal concentrations of the highly used acetamiprid (ACE) and clothianidin (CLO). In this view, we characterized their electrophysiological effects on rat α3β4 nAChRs, knowing that it is predominantly expressed in ganglia of the vegetative nervous system and the adrenal medulla, which initiates catecholamine secretion. Both molecules exhibited a weak agonist effect on α3β4 receptors. Accordingly, their influence on epinephrine secretion from rat adrenal glands was also weak at 100 μM, but it was stronger at 500 μM. Challenging ACE or CLO together with nicotine (NIC) ended up with paradoxical effects on secretion. In addition, we measured the rat arterial blood pressure (ABP) in vivo by arterial catheterization. As expected, NIC induced a significant increase in ABP. ACE and CLO did not affect the ABP in the same conditions. However, simultaneous exposure of rats to both NIC and ACE/CLO promoted an increase of ABP and induced a biphasic response. Modeling the interaction of ACE or CLO on α3β4 nAChR is consistent with a binding site located in the agonist pocket of the receptor. We present a transversal experimental approach of mammal intoxication with neonicotinoids at different scales, including in vitro, ex vivo, in vivo and in silico. It paves the way of the acute and chronic toxicity for this class of insecticides on mammalian organisms.

Effects of in utero and lactational exposure to the no-observed-adverse-effect level (NOAEL) dose of the neonicotinoid clothianidin on the reproductive organs of female mice

Recently, developmental exposure to clothianidin (CLO) has been shown to cause reproductive toxicity in male mice, but the effects in female mice remain to be clarified. Pregnant C57BL/6N mice were given a no-observed-adverse-effect-level (NOAEL) dose of CLO until weaning. We then examined ovaries of 3- or 10-week-old female offspring. In the CLO-administered group, morphological changes, a decrease in the immunoreactivity of the antioxidant enzyme glutathione peroxidase 4 (GPx4), and activation of genes in the steroid hormone biosynthesis pathway were observed in 3-week-old mice, and decreases of GPx4 immunoreactivity, 17OH-progesterone and corticosterone levels were observed in 10-week-old mice, along with high rates of infanticide and severe neglect, providing new evidence that developmental exposure to CLO affects juvenile and adult mice differently.

Joint toxicity of imidacloprid and azoxystrobin to Chironomus dilutus at organism, cell, and gene levels

Pesticides occur in the environment as mixtures, yet the joint toxicity of pesticide mixtures remains largely under-explored and is usually overlooked in ecological risk assessment. In the current study, joint toxicity of a neonicotinoid insecticide (imidacloprid, IMI) and a strobilurin fungicide (azoxystrobin, AZO) was investigated with Chironomus dilutus over a wide range of concentrations and at different effect levels (organism, cell, and gene levels). The two pesticides, both individually and in combination, were found to induce oxidative stress and cause lethality in C. dilutus. Median lethal concentrations for IMI and AZO were 3.98 ± 1.17 and 52.9 ± 1.1 μg/L, respectively. Mixtures of the two pesticides presented synergetic effects at environmentally relevant concentrations whilst antagonistic effects at high concentrations, showing concentration-dependent joint toxicity. Investigation on the expressions of 12 genes (cyt b, coi, cox1, cyp4, cyp12m1, cyp9au1, cyp6fv1, cyp315, gst, Zn/Cu-sod, Mn-sod, and cat) revealed that the two pesticides impaired mitochondrial respiration, detoxification, and antioxidant system of C. dilutus, and the joint effects of the two pesticides were likely due to an interplay between their respective influences on these physiological processes. Collectively, the synergistic effects of the two pesticides at environmentally relevant concentrations highlight the importance to incorporate combined toxicity studies into ecological risk assessment of pesticides.

Evaluation of FGFR1 as a diagnostic biomarker for ovarian cancer using TCGA and GEO datasets

Background

Malignant ovarian cancer is associated with the highest mortality of all gynecological tumors. Designing therapeutic targets that are specific to OC tissue is important for optimizing OC therapies. This study aims to identify different expression patterns of genes related to FGFR1 and the usefulness of FGFR1 as diagnostic biomarker for OC.

Methods

We collected data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. In the TCGA cohort we analyzed clinical information according to patient characteristics, including age, stage, grade, longest dimension of the tumor and the presence of a residual tumor. GEO data served as a validation set. We obtained data on differentially expressed genes (DEGs) from the two microarray datasets. We then used gene set enrichment analysis (GSEA) to analyze the DEG data in order to identify enriched pathways related to FGFR1.

Results

Differential expression analysis revealed that FGFR1 was significantly downregulated in OC specimens. 303 patients were included in the TCGA cohort. The GEO dataset confirmed these findings using information on 75 Asian patients. The GSE105437 and GSE12470 database highlighted the significant diagnostic value of FGFR1 in identifying OC (AUC = 1, p = 0.0009 and AUC = 0.8256, p = 0.0015 respectively).

Conclusions

Our study examined existing TCGA and GEO datasets for novel factors associated with OC and identified FGFR1 as a potential diagnostic factor. Further investigation is warranted to characterize the role played by FGFR1 in OC.

Regulation of aromatase in cancer

The regulation of aromatase, an enzyme involved in the biosynthesis of estrogen in normal and cancer cells, has been associated with growth factor signaling and immune response modulation. The tissue-specific regulatory roles of these factors are of particular importance as local aromatase expression is strongly linked to cancer development/progression and disease outcomes in patients. Therefore, aromatase has become a chemotherapeutic target and aromatase inhibitors (AIs) are used in the clinic for treating hormone-dependent cancers. Although AIs have shown promising results in the treatment of cancers, the emerging increase in AI-resistance necessitates the development of new and improved targeted therapies. This review discusses the role of tumor and stromal-derived growth factors and immune cell modulators in regulating aromatase. Current single-agent and combination therapies with or without AIs targeting growth factors and immune checkpoints are also discussed. This review highlights recent studies that show new connections between growth factors, mediators of immune response, and aromatase regulation.

A nationwide study of occurrence and exposure assessment of neonicotinoid insecticides and their metabolites in drinking water of China

Neonicotinoid insecticides (NNIs) are the most extensively used insecticides worldwide, threatening ecosystem and human health. However, nationwide studies of NNIs and their metabolites in drinking water are limited. In order to characterize the contamination status of NNIs in drinking water throughout China, we collected 884 drinking water samples including 789 tap water and 95 groundwater samples from 32 provinces (covering seven regions of mainland China: south, central, east, north, northeast, northwest, and southwest) and Hong Kong. Ten NNIs and six of their main metabolites were determined in the water samples. The relative potency factor method was used to assess the cumulative concentrations of NNIs and their metabolites (imidacloprid-equivalent total NNIs, IMI_eq) based on the chronic reference doses (cRfDs) of the NNIs or the toxic effects of the mataboilites. The IMI_eq varied among the studied regions, with a median concentration of 24.5 ng/L and a maximum concentration of 8,622 ng/L. The predominant NNIs in drinking water were acetamiprid (ACE) and imidacloprid (IMI). Compared with tap water derived from groundwater, much higher concentrations of IMI_eq and NNIs were found in tap water derived from surface water. Different concentrations and patterns of NNIs in drinking water were observed in different regions, provinces, and capital cities, mainly due to regional and provincial differences in crop types and volumes of pesticide usage. The concentrations of NNIs in the drinking water of provincial capitals and small/medium cities were higher than the concentrations in rural areas. The estimated daily intake (EDI) of IMI_eq was at least two orders of magnitude lower than the cRfD of IMI, while the NNIs in 16 drinking water samples exceeded the acceptable value (100 ng/L) recommended by the European Union. This study provided a nationwide profile of the occurrence of NNIs and their metabolites in the drinking water of China and the associated potential cumulative human health risks, taking into account of the toxicity differences between NNIs and their metabolites.

Exposure to Endocrine Disrupting Chemicals and Risk of Breast Cancer

Breast cancer (BC) is the second most common cancer and the fifth deadliest in the world. Exposure to endocrine disrupting pollutants has been suggested to contribute to the increase in disease incidence. Indeed, a growing number of researchershave investigated the effects of widely used environmental chemicals with endocrine disrupting properties on BC development in experimental (in vitro and animal models) and epidemiological studies. The complex effects of endocrine disrupting chemicals (EDCs) on hormonal pathways, involving carcinogenic effects and an increase in mammary gland susceptibility to carcinogenesis-together with the specific characteristics of the mammary gland evolving over the course of life and the multifactorial etiology of BC-make the evaluation of these compounds a complex issue. Among the many EDCs suspected of increasing the risk of BC, strong evidence has only been provided for few EDCs including diethylstilbestrol, dichlorodiphenyltrichloroethane, dioxins and bisphenol A. However, given the ubiquitous nature and massive use of EDCs, it is essential to continue to assess their long-term health effects, particularly on carcinogenesis, to eradicate the worst of them and to sensitize the population to minimize their use.

Nationwide Biomonitoring of Neonicotinoid Insecticides in Breast Milk and Health Risk Assessment to Nursing Infants in the Chinese Population

Presently, the potential health risks of neonicotinoid insecticides (neonics) are now receiving much attention, but no data regarding the exposure of infants to neonics via human breast milk intake have been reported. In this study, a nationwide survey was conducted during the period of 2017-2019, wherein 97 pooled breast milk samples were collected from 3570 lactating women of 23 provinces in China. Nationally, acetamiprid-N-desmethyl was the most predominant compound, accounting for 61.2% of the total amount of neonics, followed by imidacloprid (15.6%). The concentration of the sum of acetamiprid and its metabolite acetamiprid-N-desmethyl in breast milk was positively correlated with corresponding dietary exposure, while no statistically significant association between the other neonic levels in breast milk and dietary exposure was found. The cumulative daily intakes of neonics (9.40-249 ng kg^-1 of body weight day^-1) were estimated for breastfed infants, indicating a minuscule risk to Chinese infants from neonic exposure via breastfeeding.

Predictors, sources, and health risk of exposure to neonicotinoids in Chinese school children: A biomonitoring-based study

BACKGROUND

Recent studies have suggested an extensive exposure to neonicotinoids in human, but the information on predictors, sources, and health risk remains limited in children.

OBJECTIVE

To explore the predictors, sources, and health risk for exposure of Chinese school children to neonicotinoids by biomonitoring method.

METHODS

In 2019, 309 school children aged 7-11 years were selected from a dynamic cohort of children established in Shanghai, East China. Eight neonicotinoids and four metabolites were determined in first morning urine. After detailed information on demographic and socioeconomic indices, intake of drinking water, food consumption, and anthropometric measurements was collected, the predictors and sources of exposure to neonicotinoids were explored by binary and ordinal logistic regression models. Health risk was assessed by the hazard quotient (HQ) and hazard index (HI) based on estimated daily exposure dose.

RESULTS

Six neonicotinoids (thiamethoxam, clothianidin, imidacloprid, acetamiprid, nitenpyram, and dinotefuran) and three metabolites (N-desmethyl-thiamethoxam, N-desmethyl-clothianidin, and N-desmethyl-acetamiprid) were detected in 81.3% of urine samples. Children in nuclear family or girls had a higher detection frequency of thiamethoxam. N-desmethyl-acetamiprid was more likely to be detected in children who were older, physically active, or obese. Parents' occupation was heterogeneously associated with the detection of thiamethoxam and clothianidin. Thiamethoxam and clothianidin were more likely to be detected in children consuming more fresh vegetables in all or its specific items of cabbage, nori, and kelp. N-desmethyl-acetamiprid was more likely to be detected in children who drank more tap water. The maximum HQ and HI were 0.3522 and 0.5187, respectively, and 2.8% of children had a HI between 0.1 and 1.

CONCLUSION

Predictors for the exposure of children to neonicotinoids included demographic and socioeconomic factors, physical exercise, and relative body weight. Tap water and fresh vegetables were potential sources. A low risk was posed on children's health by the neonicotinoids.

Molecular Basis for Endocrine Disruption by Pesticides Targeting Aromatase and Estrogen Receptor

The intensive use of pesticides has led to their increasing presence in water, soil, and agricultural products. Mounting evidence indicates that some pesticides may be endocrine disrupting chemicals (EDCs), being therefore harmful for the human health and the environment. In this study, three pesticides, glyphosate, thiacloprid, and imidacloprid, were tested for their ability to interfere with estrogen biosynthesis and/or signaling, to evaluate their potential action as EDCs. Among the tested compounds, only glyphosate inhibited aromatase activity (up to 30%) via a non-competitive inhibition or a mixed inhibition mechanism depending on the concentration applied. Then, the ability of the three pesticides to induce an estrogenic activity was tested in MELN cells. When compared to 17β-estradiol, thiacloprid and imidacloprid induced an estrogenic activity at the highest concentrations tested with a relative potency of 5.4 × 10⁻¹⁰ and 3.7 × 10⁻⁹, respectively. Molecular dynamics and docking simulations predicted the potential binding sites and the binding mode of the three pesticides on the structure of the two key targets, providing a rational for their mechanism as EDCs. The results demonstrate that the three pesticides are potential EDCs as glyphosate acts as an aromatase inhibitor, whereas imidacloprid and thiacloprid can interfere with estrogen induced signaling.

Assessment of imidacloprid related exposure using imidacloprid-olefin and desnitro-imidacloprid: Neonicotinoid insecticides in human urine in Wuhan, China

While neonicotinoid insecticides (NNIs) have been widely used worldwide, limited studies have measured specific metabolites of imidacloprid (IMI, the most commonly used NNI) in human urine. To better understand human exposure to NNIs, 10 parent compounds, and 6 of their metabolites were analyzed in 408 urine samples collected from 129 healthy adults in Wuhan, Central China, during autumn and winter of 2018. These specimens included repeated urine samples taken in 3 d from 75 volunteers. The urinary concentrations of desnitro-imidacloprid (DN-IMI), imidacloprid-olefin (IMI-olefin), and desmethyl-acetamiprid (DM-ACE) were higher (4-40 times) than those of their parent compounds (IMI and acetamiprid, ACE). DN-IMI and IMI-olefin accounted for 92% of the urinary Σ₃IMI (the sum of IMI and its specific metabolites measured). Positive correlations (r) were observed between DN-IMI and IMI (0.50), IMI-olefin and IMI (0.75), and DM-ACE and ACE (0.53). Good to excellent inter-day reliabilities (unadjusted intraclass correlation coefficients) were observed for IMI-olefin (0.61) and DM-ACE (0.81), while moderate inter-day reliability was observed for DN-IMI (0.43). The urinary NNI concentrations were significantly higher in autumn than in winter, and higher in urban areas than in rural areas, while no significant gender or age-related differences were observed. To our knowledge, this is the first report on DN-IMI and IMI-olefin in human urine.