Maternal serum neonicotinoids during early-mid pregnancy and congenital heart diseases in offspring: An exploratory study

The association between maternal exposure to ten neonicotinoid insecticides and preterm birth in Guangxi, China

Preterm birth (PTB) is a primary cause of mortality among newborns globally. Prenatal exposure to environmental pollutants has been suggested to increase the PTB risk. Studies have shown NEOs may be linked to adverse birth outcomes. However, the impact of maternal NEOs exposure on PTB remains unclear. Therefore, to examine the association between NEOs exposure and PTB risk, we performed a case-control analysis utilizing data from a birth cohort study in Guangxi, China. A total of 157 preterm infants and 471 full-term infants were included. Concentrations of 10 NEOs and their metabolites in maternal serum were quantified using liquid chromatography-tandem mass spectrometry. We employed logistic regression, quantile g-computation, and restricted cubic spline models to evaluate the effects of individual and mixed NEOs exposures. Subsequently, XGBoost machine learning, combined with SHAP, was employed to predict the implications of serum NEOs on PTB. Finally, for 1-standard deviation increment in ln-transformed concentrations of imidacloprid and dinotefuran, significant correlations with higher odds of PTB were observed, showing odds ratios of 1.17 (95 % CI: 1.02, 1.36) and 1.41 (95 % CI: 1.16, 1.72). Similar patterns and higher risks were observed in late preterm birth. In both mixed exposure and machine learning models, dinotefuran and imidacloprid were identified as major predictors of increased PTB risk. Exposure to n-desmethylacetamiprid, sulfoxaflor, thiacloprid, nitenpyram, and thiamethoxam was negatively associated with PTB. Our findings suggested dinotefuran and imidacloprid exposure during pregnancy were risk factors of PTB, particularly among late preterm births. Subsequent research is necessary to illuminate the underlying mechanisms involved.

Cardioprotective effects of Dendrobium officinale polysaccharides on thiacloprid-induced cardiac injury via modulating mitochondrial dynamics

Thiacloprid (THI), a widely used neonicotinoid pesticide, has been shown to induce cardiac injury, though the underlying mechanisms remain poorly understood. Dendrobium officinale polysaccharides (DOP), a bioactive compound with potent antioxidant properties, may offer protection against such toxicity. This study investigated the cardioprotective effects of DOP in THI-induced cardiac injury in quails, with a particular focus on the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. Network pharmacology analysis identified key targets of DOP, linking them to oxidative stress, mitochondrial dysfunction, and inflammatory pathways. Experimental results demonstrated that DOP significantly reversed THI-induced hematological and biochemical abnormalities, including the restoration of cardiac biomarkers and mitigation of myocardial structural damage. DOP treatment notably activated the Nrf2 pathway, leading to the upregulation of antioxidant enzymes such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1), which countered THI-induced oxidative stress. Additionally, DOP restored mitochondrial dynamics by balancing mitochondrial fission and fusion proteins. These findings highlight the central role of Nrf2 activation in the cardioprotective effects of DOP, suggesting that DOP may serve as a promising therapeutic agent for mitigating pesticide-induced cardiovascular toxicity.

6-Chloronicotinic Acid Induces Toxicity in Mouse Neural Stem Cells via the C3ar1 Signaling

Neural stem cells (NSCs) are essential for brain development due to their ability to proliferate and differentiate into various neural cell types. Neonicotinoid insecticides (NNIs), which have replaced traditional pesticides, are now widely used and frequently detected in environmental and biological samples. Prenatal exposure to NNIs has been associated with an increased risk of neurodevelopmental disorders in offspring, yet the causal relationship and the underpinning mechanism remain to be clarified. As one of the primary metabolites of chloropyridinyl neonicotinoids, 6-chloronicotinic acid (6-ClNA) has been identified as a potential neurotoxin, though its effects on NSCs have not been fully explored. Here, we demonstrate that 6-ClNA exposure significantly disrupted NSC proliferation and differentiation in vitro. Transcriptomic analyses revealed that 6-ClNA altered the expression of pathways related to proliferation, apoptosis, and inflammation, with notable activation of the C3ar1/C1qa signaling axis. Genetic ablation of C3ar1 using siRNA markedly restored NSC proliferation and neurosphere formation, as well as reduced apoptosis, suggesting a central role of C3ar1/C1qa in mediating 6-ClNA's neurotoxic effects. These findings imply that early-life exposure to NNIs may affect the fitness and function of NSCs, wherein the C3ar1 pathway plays an indispensable role.

Urinary neonicotinoid exposure and its association with hypertension and dyslipidemia among the elderly: A cross-sectional study in Shenzhen, China

In recent years, neonicotinoids (NEOs) as a new type of insecticide have been increasingly used worldwide, causing significant impacts on human health. This study collected urine samples from 1147 elderly individuals (including 714 in the control group and 433 in the hypertension group) in Shenzhen, China, and detected the concentrations of six types of NEOs and four metabolites of NEOs (mNEOs). The aim of this study is to investigate the association between NEOs exposure and hypertension and dyslipidemia. After measurement, we find that the lowest detection rate (DR) among NEOs is imidacloprid (IMI), at only 39.3%. The NEO with the highest urine median concentration is dinotefuran (DIN) (1.31 μg/L), while the mNEO with the highest median concentration is DM-ACE (2.74 μg/L). Through univariate analysis, we found that DM-THM may promote the development of hypertension, while logistic regression indicated that IMI-OF could be a risk factor for hypertension. As prototypes of these two metabolites, thiamethoxam (THM) and IMI may also be risk factors for hypertension. Linear regression analysis revealed a negative correlation between the concentration of thiamethoxam (THD) and low-density lipoprotein (LDL) level, while DIN was positively correlated with triglyceride (TG) level and negatively correlated with high-density lipoprotein (HDL) level. Mediation effect analysis showed that THD may influence the risk of hypertension in the elderly by affecting LDL level. Based on this study, we believe that exposure to NEOs may increase the risk of hypertension in the elderly population.

The impact of neonicotinoid pesticides on reproductive health

Neonicotinoids are some of the most widely used insecticides in the world because they broadly target chewing and sucking insects. Neonicotinoids are used in commercial agricultural systems, sold for use in home gardens, and found in veterinary pharmaceuticals in the form of flea and tick preventatives for companion animals. They are also used as crop seed treatments and spread throughout crops as they mature. As a result, humans, wildlife, livestock, and pets are routinely exposed to neonicotinoids through the consumption of contaminated food and water as well as through the use of some veterinary pharmaceuticals. Although several studies indicate that neonicotinoid exposure causes genotoxicity, neurotoxicity, hepatotoxicity, and immunotoxicity in some non-target species, the impact of neonicotinoid pesticides on the male and female reproductive systems in mammals is largely understudied. This review summarizes current insights on the impact of common neonicotinoid pesticides such as acetamiprid, clothianidin, imidacloprid, and thiacloprid on male and female reproductive health in mammals. The review also summarizes the impacts of exposure to mixtures of neonicotinoids on reproductive endpoints. In addition, this review highlights where gaps in research on neonicotinoid pesticides and reproductive health exist so that future studies can be designed to fill current gaps in knowledge.

The Relationship Between Maternal Exposure to Endocrine-Disrupting Chemicals and the Incidence of Congenital Heart Diseases: A Systematic Review and Meta-Analysis

BACKGROUND

Congenital heart diseases are among the most common birth defects, significantly impacting infant health. Recent evidence suggests that exposure to endocrine-disrupting chemicals may contribute to the incidence of congenital heart diseases. This study systematically reviews and analyzes the association between maternal endocrine-disrupting chemicals exposure and congenital heart diseases.

METHODOLOGY

This systematic review and meta-analysis followed the Cochrane Handbook and PRISMA guidelines. We included studies assessing the link between maternal exposure to various endocrine-disrupting chemicals and the incidence of congenital heart diseases without restricting the study design or exposure assessment methods. Data were extracted from four databases, including PubMed, Scopus, Web of Science, and Cochrane Library, up to June 2024. Quality assessment of observational studies was conducted using the Newcastle-Ottawa Scale. Statistical analysis was performed using RevMan software version 5.3, presenting results as odds ratios with 95% confidence intervals.

RESULTS

Fifty-nine studies were included in the meta-analysis. The pooled analysis revealed a significant association between maternal endocrine-disrupting chemical exposure and the incidence of congenital heart diseases when measured using human samples (odds ratio = 1.63, 95% confidence interval [1.35-1.97], p < 0.00001). Notably, exposure to heavy metals, polycyclic aromatic hydrocarbons, and perfluoroalkyl compounds was strongly associated with congenital heart diseases. However, non-sample-based methods showed no significant overall correlation (odds ratio = 1.08, 95% confidence interval [0.93-1.26], p = 0.30), except for housing renovation compounds, which were linked to a higher incidence of congenital heart diseases.

CONCLUSIONS

Maternal exposure to specific endocrine-disrupting chemicals, particularly heavy metals and polycyclic aromatic hydrocarbons, significantly increases the risk of congenital heart diseases. These findings underscore the need for preventive measures to reduce endocrine-disrupting chemicals exposure during pregnancy and further research to elucidate the underlying mechanisms.

Maternal pesticide exposure and risk of birth defects: a population-based cross-sectional study in China

Objective

This study aimed to examine the association between maternal pesticide exposure during the periconceptional period and birth defects in their offspring.

Methods

A survey was conducted among 29,204 women with infants born between 2010 and 2013 in Shaanxi Province, Northwest China. All cases of birth defects were diagnosed using the International Classification of Diseases, Tenth Revision (ICD-10). Given the multistage sampling design, the generalized estimating equation (GEE) binomial regression models with log link and exchangeable correlation structures were used to analyze the association between maternal pesticide exposures and birth defects.

Results

Among the 29,204 subjects, 562 mothers had children with birth defects, resulting in an incidence rate of 192.44 per 10,000 live births. The incidence of birth defects was higher in the pesticide-exposed group compared to the control group (737.46/10,000 vs. 186.04/10,000). After adjusting for baseline demographic characteristics, fertility status, nutritional factors, and environmental factors in the GEE model, the results indicated that the risk of birth defects and cardiovascular system defects in mothers exposed to pesticides during the periconceptional period was 2.39 times (95% CI: 1.84-3.10) and 3.14 times (95% CI: 1.73-5.71) higher, respectively, compared to the control group.

Conclusion

This study demonstrated that maternal exposure to pesticides during the periconceptional period was associated with an increased risk of birth defects, particularly cardiovascular system defects in offspring. Consequently, it would be beneficial to avoid pesticide exposure from three months before pregnancy through the first trimester to lower birth defects in infants.

Imidacloprid affects human cells through mitochondrial dysfunction and oxidative stress

Given their relatively low persistence and mammalian toxicity, neonicotinoid pesticides have been extensively used worldwide and are omnipresent in the environment. Recent studies have shown that neonicotinoids may pose adverse effects on non-target organisms other than the known neurotoxicity, raising emerging concerns that these insecticides might pose human health risk through additional toxicity pathways. In the present study, the mitochondria function, oxidative stress, DNA damages, and genes transcription levels were examined in the human neuroblastoma SH-SY5Y cells after 48-h exposure to imidacloprid at concentrations from 0.05 to 200 μmol/L. Results showed that imidacloprid induced mitochondrial dysfunction with the degradation of adenosine triphosphate (ATP) and mitochondrial membrane potential (MMP) levels. In addition, imidacloprid caused oxidative stress by stimulating the generation of reactive oxygen species (ROS) and hydrogen peroxide (H2O2) via the disruption of calcium ion level and mitochondrial function. Ultimately, the oxidative stress continued to produce DNA damage and apoptosis in SH-SY5Y cells at imidacloprid concentrations above 47.6 μmol/L. Among the evaluated endpoints, ATP was the most sensitive, with a median activity concentration of 0.74 μmol/L. The 5 % hazard concentration of imidacloprid was estimated to be 0.69 μmol/L, which can be used as a threshold for human health risk assessment for imidacloprid. Collectively, our results provide an important support for further research on potential toxicity of neonicotinoids related to mitochondrial toxicity in humans.

Imidacloprid unique and repeated treatment produces cholinergic transmission disruption and apoptotic cell death in SN56 cells

Imidacloprid (IMI), the most widely used worldwide neonicotinoid biocide, produces cognitive disorders after repeated and single treatment. However, little was studied about the possible mechanisms that produce this effect. Cholinergic neurotransmission regulates cognitive function. Most cholinergic neuronal bodies are present in the basal forebrain (BF), regulating memory and learning process, and their dysfunction or loss produces cognition decline. BF SN56 cholinergic wild-type or acetylcholinesterase (AChE), β-amyloid-precursor-protein (βAPP), Tau, glycogen-synthase-kinase-3-beta (GSK3β), beta-site-amyloid-precursor-protein-cleaving enzyme 1 (BACE1), and/or nuclear-factor-erythroid-2-related-factor-2 (NRF2) silenced cells were treated for 1 and 14 days with IMI (1 μM-800 μM) with or without recombinant heat-shock-protein-70 (rHSP70), recombinant proteasome 20S (rP20S) and with or without N-acetyl-cysteine (NAC) to determine the possible mechanisms that mediate this effect. IMI treatment for 1 and 14 days altered cholinergic transmission through AChE inhibition, and triggered cell death partially through oxidative stress generation, AChE-S overexpression, HSP70 downregulation, P20S inhibition, and Aβ and Tau peptides accumulation. IMI produced oxidative stress through reactive oxygen species production and antioxidant NRF2 pathway downregulation, and induced Aβ and Tau accumulation through BACE1, GSK3β, HSP70, and P20S dysfunction. These results may assist in determining the mechanisms that produce cognitive dysfunction observed following IMI exposure and provide new therapeutic tools.

Paralysis caused by dinotefuran at environmental concentration via interfering the Ca2+-ROS-mitochondria pathway in Chironomus kiiensis

Introduction

Dinotefuran as the third-generation of neonicotinoid insecticides is extensively used in agriculture worldwide, posing a potential toxic threat to non-target animals and humans. However, the chronic toxicity mechanism related to mitochondria damage of dinotefuran to non-target animals at environmental concentration is unclear.

Methods

In this study, the mitochondria damage and oxidative stress of dinotefuran on Chironomus kiiensis were investigated at environmental concentrations by long-term exposure. At the same time, relevant gene expressions of these toxicity indexes were measured as sensitive ecotoxicity biomarkers to reflect the toxic effects of dinotefuran on Chironomidae.

Results

Our present study showed that chronic exposure to environmental concentrations of dinotefuran resulted in behavioral inhibition in the larvae of Chironomidae. For burrowing inhibition of 10 days, the lowest observed-effect concentration (LOEC) and 50% inhibitory concentration (IC50) were 0.01 (0.01-0.04) and 0.60 (0.44-0.82) μg/L, respectively. Dinotefuran promoted the release of intracellular calcium ions (Ca2+) in Chironomidae via dysregulating the gene expressions of atp2b, camk ii, and calm. Subsequently, the disruption of the Ca2+ signaling pathway induced oxidative stress by raising reactive oxygen species (ROS), hydrogen peroxide (H2O2), and malonaldehyde (MDA) levels. Thus, the over-release of Ca2+ and ROS disordered the normal functioning of mitochondrial-related pathways by dysregulating the expressions of mitochondria-related genes of atpef0a, sdha, and cyt b.

Conclusion

Our findings showed that low environmental concentrations of dinotefuran caused paralysis of the midge via interfering the Ca2+-ROS-mitochondria pathway. These results provided data support for assessing the potential environmental risk of dinotefuran.

Exposure of pregnant women to neonicotinoids in Wenzhou City, East China: A biomonitoring study

BACKGROUND

China produces and consumes a large amount of neonicotinoids. A non-negligible exposure to neonicotinoids might occur for Chinese pregnant women, but relevant data remain limited.

OBJECTIVE

To investigate the exposure to neonicotinoids by urinary biomonitoring in pregnant women from Wenzhou City, East China.

METHODS

We selected 432 pregnant women in Wenzhou City in 2022. A total of eight parent neonicotinoids and four metabolites were determined in single spot urine by liquid chromatography coupled to mass spectrometry. Basic characteristics, physical activity, pre-pregnant body mass index, and intake of drinking water and food were investigated by the questionnaire. Health risk was assessed by hazard quotient (HQ) and hazard index (HI) based on human safety thresholds derived from different health endpoints.

RESULTS

Neonicotinoids and their metabolites in urine had a detection frequency between 0 % and 80.1 %. At least one neonicotinoid or metabolite was detected in 93.5 % of urine samples. Except for clothianidin (51.2 %) and N-desmethyl-acetamiprid (80.1 %), the detection frequencies of other neonicotinoids and metabolites ranged from 0 % to 43.8 %. The summed concentrations of all neonicotinoids and their metabolites ranged from < LOD to 222.83 μg/g creatinine with the median concentration of 2.58 μg/g creatinine. Maternal age, educational level, occupation, household income, screen time, and pre-pregnant body mass index were associated with detection frequencies or concentrations of neonicotinoids and their metabolites. Pregnant women with higher consumption frequencies of wheat, fresh vegetable, shellfish, fresh milk, and powdered milk had higher detection frequencies of neonicotinoids and their metabolites. Both HQ and HI were less than one.

CONCLUSIONS

Overall, pregnant women in Wenzhou City showed a notable frequency of exposure to at least one neonicotinoid, although the exposure frequency for each specific neonicotinoid was generally low. Several food items derived from plants and animals were potential exposure sources. A low health risk was found based on current safety thresholds.