Ecotoxicology and Environmental Safety最新文献

Indole-3-acetic acid (IAA) can regulate plant growth and thus modulate the accumulation of polycyclic aromatic hydrocarbons (PAHs). However, the effect of endogenous IAA on PAHs accumulation and its influencing factors remains unclear. To unravel this, two different IAA expression genotypes of Arabidopsis thaliana, i.e., IAA-underproducing yucca1D [YUC1] mutant and wild type [WT]) were selected and treated with different fluoranthene (Flu) concentrations (0 mg/L [CK], 5 mg/L [Flu5], and 20 mg/L [Flu20]) to reveal the impact mechanism of endogenous IAA on Flu uptake by plants. The results indicated that under Flu5 treatment, the bioconcentration factors (BCF) and translocation factors (TF) of Flu in WT were 41.4 % and 14.3 % higher than those in YUC1. Similarly, under Flu20 treatment, the BCF and TF of Flu in WT were also 42.2 % and 8.2 % higher than those in YUC1. In addition, the BCF and TF were 72.5 % and 35.8 % higher under Flu5 treatment compared to Flu20 treatment for WT, and 73.4 % and 28.6 % higher respectively for YUC1. Moreover, WT exhibited higher plant growth (biomass, root morphology indicators [root length, root area and number of tips]) and IAA content compared to YUC1 under identical Flu treatments. Plant growth and IAA content declined with the increase of Flu concentration in both YUC1 and WT leaves compared with CK treatment. Conversely, in WT roots, root biomass and morphology indicators promoted followed by a decrease as the concentration of Flu increased. Additionally, the antioxidant enzyme activities (SOD, POD, and CAT) of WT were 11.1 %, 16.7 %, and 28.9 % higher than those of YUC1 under Flu5 treatment, and 13.6 %, 12.9 %, and 26.5 % higher under Flu20 treatment. Compared with CK treatment, SOD and POD activities promoted with increasing Flu concentration, whereas CAT activities decreased. Variability separation analysis revealed that level of IAA primarily influenced Flu accumulation in WT or under Flu5 treatments, whereas antioxidant enzyme activity primarily affected Flu accumulation in YUC1 or under Flu20 treatments. Exploring the relationship between the IAA synthesis gene YUCCA and IAA levels, alongside Flu accumulation, could yield novel insights into the regulation of PAH accumulation in plants.

The submerged plant Vallisneria natans plays an important role in the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated sediments. In this study, V. natans and sediments were collected from different V. natans natural vegetation zones, and sediment mesocosms were set up for phytoremediation tests. In addition, commercial-grade V. natans were obtained from the Fish-Bird-Flower market for comparison with phytoremediation. Phytoremediation using V. natans from natural growth significantly increased the degradation of PAHs in Dashui Harbor (0.0148±0.0015 d⁻¹) and Taihu Lake bay sediments (0.0082±0.0010 d⁻¹) but not in commercial-grade V. natans. Transplanted V. natans from natural growth had a significant (p=0.002) effect on PAH degradation, especially in highly PAH-contaminated sedimentary environments. The distinct bacterial communities were strongly affected by sediment type and V. natans type, which contributed to different phytoremediation patterns. Less complex but more stable microbial co-occurrence networks play key roles in improving PAH phytoremediation potential. In addition, V. natans from natural growth in highly PAH-contaminated sediment could adapt to PAH stress by exuding tryptophan metabolites to assemble health-promoting microbiomes. This study provides novel evidence that initial microbial and physicochemical characteristics of sediment and submerged plant types should be considered in the use of bioremediation management strategies for organic pollutant-contaminated sediments.

The severity of soil molybdenum (Mo) pollution is increasing, and effective management of contaminated soil is essential for the sustainable development of soil. To investigate this, a pot experiment was carried out to assess the impact of different rates of humic acid (HA) and fulvic acid (FA) on the mobility of Mo in soil solution and its uptake by alfalfa, wheat and green bristlegrass. The concentration of Mo in Plants and soil was determined using an Atomic Absorption Spectrophotometer. The findings revealed that the application of HA led to an increase in Mo accumulation in the shoot and root of green bristlegrass and wheat, ranging from 10.56 % to 28.73 % and 62.15–115.79 % (shoot), and 17.52–46.53 % and 6.29-81.25 % (root), respectively. Nonetheless, the use of HA resulted in a slight inhibition of plant Mo uptake, leading to reduced Mo accumulation in alfalfa roots compared to the control treatment (from 3284.49 mg/kg to 2140.78–2813.54 mg/kg). On the other hand, the application of FA decreased Mo accumulation in the wheat shoot (from 909.92 mg/kg to 338.54–837.45 mg/kg). Furthermore, the bioavailability of green bristlegrass (with HA) and wheat (with FA) decreased, and the percentage of residual fraction of Mo increased (from 0.39 % to 0.78–0.96 %, from 3.95 % to 3.97∼ 4.34 %). This study aims to elucidate the ternary interaction among Mo, humic substances, and plants (alfalfa, wheat, and green bristlegrass), to enhance both the activation and hyperaccumulation of Mo simultaneously.

A new and highly sensitive voltammetric technique was described in this study for the concurrent detection of endocrine disruptors bisphenol A (BPA) and bisphenol AF (BPAF) based on carbon nanocages (CNCs) and copper oxide nanochains (CuONCs). The CNCs was prepared by the solvothermal method and characterized using various techniques. Utilizing the nanocomposite of CNCs and CuONCs, the voltammetric sensor demonstrated outstanding performance in detecting BPA and BPAF simultaneously with distinct oxidation peaks and increased current peaks. The voltammetric signals have linear relationships with the two bisphenols ranging from 0.500 μM to 100 μM with a detection limit of 0.16 µM for BPA and 0.14 µM for BPAF. The newly designed sensor showed reliable consistency, long-term durability and anti-interference ability, and performed well in analyzing real water samples, indicating great potential for environmental monitoring.

Background

Mold exposure is a common environmental issue that can adversely affect health, particularly among older adults. The impact of mold exposure on anxiety symptoms in this population has not been extensively studied.

Objective

This study aims to examine the relationship between mold exposure and anxiety symptoms in older adults, considering the mediating role of cognitive function and the moderating effects of open window ventilation and multivitamin supplementation.

Methods

Data from the eighth wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) was utilized, including 11,021 participants aged 65 and older. Logistic regression models and moderated mediation analysis were employed to explore these relationships.

Results

Mold exposure was significantly associated with increased anxiety symptoms (OR=1.831, 95 % CI=1.588–2.110). Cognitive impairment partially mediated this relationship. Open window ventilation (B=-0.040, P<0.001) and multivitamin supplementation (B=-0.197, P<0.001) served as protective factors. Subgroup analysis indicated higher vulnerability among females (OR=1.72, P<0.001), those aged 65–79 (OR=1.86, P<0.001), urban residents (OR=2.50, P<0.001), individuals not living with family members (OR=1.89, P<0.001), those with higher education (OR=2.01, P<0.001), married individuals (OR=1.80, P<0.001), and those in very good health (OR=2.11, P=0.026).

Conclusion

Mold exposure contributes to anxiety symptoms in older adults, with cognitive decline playing a mediating role. Effective interventions, including improved ventilation and multivitamin supplementation, can mitigate these effects. These findings highlight the need for targeted public health strategies to enhance the well-being of older adults.

Isobutyronitrile finds extensive application in organic synthesis for the production of the insecticide diazinon. Apart from occupational exposure, cigarette smoking may also expose the general population to isobutyronitrile. However, to date, the association between isobutyronitrile and female infertility has not been explored in a population-based study. Hence, we analysed data from 1254 women, aged 18–44, with blood isobutyronitrile results and infertility questionnaires, from National Health and Nutrition Examination Survey (NHANES) 2015–2016 and NHANES 2017-March 2020. To compare differences, weighted chi-square tests were conducted for categorical variables and weighted regression models were performed for continuous variables. Logistic regression and generalized linear models were applied to examine the associations. Each standard deviation increment (SD=0.026) of isobutyronitrile increased the risk of infertility by 24 % after adjusting for potential confounders in logistic regression model (aOR=1.24; 95 % CI: 1.06–1.46). In women who had been pregnant and gave birth, the results exhibited a consistent linear relationship. The participants were classified into two groups, namely positive and negative, using an isobutyronitrile cut-off value that exceeded 0.040 ng/mL. The positive group did not demonstrate a statistically significant correlation (aOR=1.55; 95 % CI: 0.66–3.65). According to smooth curve fitting, isobutyronitrile and infertility was linearly related across the entire range, and no threshold effect was found. Particularly, non-Hispanic Black women had a significantly stronger association with isobutyronitrile exposure and infertility (aOR=4.27; 95 % CI: 1.32–13.83). In conclusion, our study was the first report of an independent association of isobutyronitrile with infertility, especially in non-Hispanic Black women. Additional fundamental research on nonhuman primates, along with comprehensive clinical studies, are necessary to fully elucidate the intricate mechanisms underlying isobutyronitrile activity.

Fine particulate matter (PM2.5) exposure has been extensively linked to reproductive and developmental dysfunctions, yet the underlying mechanisms remain elusive. This study employed single-cell RNA sequencing (scRNA-seq) to investigate PM2.5-induced changes in uterine cell populations and gene expression profiles in mice during estrus and early pregnancy. Methodologically, we intranasally inoculated mice with 20 μL of 4.0 mg/mL PM2.5 suspension during their estrus and early pregnancy periods. Utilizing scRNA-seq analysis, we revealed significant alterations in cell type composition following PM2.5 exposure. Notably, we observed a marked decrease in the proportion of natural killer (NK) cells in PM2.5-exposed mice (2.00 % vs. 8.97 % in controls). Further functional enrichment analysis identified suppression of the IL-17 signaling pathway in NK cells as a key mechanism of PM2.5-induced toxicity. GSEA analysis showed in-depth details of the downregulated genes in this pathway, including Fosb, S100a8, Tnfaip3, IL-17a, and S100a9. PM2.5 exposure also disrupted intercellular communication within the uterine microenvironment, with the number of cell interactions decreasing from 483 to 315 and interaction strength reducing from 12.43 to 6.78 compared to controls. Histological examination revealed that PM2.5 exposure led to thinning of the endometrium and less prominent main branches in uterine tissues, and immunofluorescence assays corroborated the altered expression of IL-17 pathway components, showing enhanced Hsp90ab1 expression and reduced FOSB, S100A8, and S100A9 expression in PM2.5-exposed uterine tissues. These findings provide novel insights into the cellular mechanisms of PM2.5-induced reproductive toxicity, highlighting the IL-17 signaling pathway in uterine NK cells as a potential target for therapeutic interventions. Our results underscore the need for air quality regulations and open new avenues for developing biomarkers and targeted therapies to mitigate the reproductive risks associated with PM2.5 exposure.