Environmental Research最新文献

The pollution of micro- and mesoplastic (MMP) in the Eastern Indian Ocean (EIO) remains poorly understood. The present study revealed that MMP abundance in nekton from EIO in 2022 (mean: 2.30 ± 0.39 items individual^-1 and 1.81 ± 0.54 items g^-1) was significantly higher than that in 2021 (mean: 1.60 ± 0.22 items individual^-1 and 0.80 ± 0.13 items g^-1). In contrast, MMP abundance in surface water varied insignificantly between 2021 (mean: 0.04 ± 0.01 items m^-3) and 2022 (mean: 0.05 ± 0.02 items m^-3). The rise in predominant polymers-polypropylene (PP), rayon (RA), and polyester (PES)-in nekton from 2021 to 2022 may suggest increased pollution from face masks and home textiles along coastal regions. Notable spatial variation in PP and RA between the northeastern and southeastern regions was observed only in nekton, suggesting they are better indicators of MMP spatiotemporal variation than surface water. Shadow driftfish ingested more MMPs than purpleback flying squid and mackerel scad, likely due to its deeper habitat. By simultaneously considering color, composition, and shape, integrated MMP analysis showed insignificant correlation between MMP pollution in surface water and nekton, suggesting that nekton may ingest MMPs through multiple pathways beyond surface water. Risk indices for surface water and nekton reached moderate to upper levels globally, emphasizing the need for continued monitoring in the EIO. Epoxy resin, rubber, and PP + acrylic were identified as the most hazardous polymers, providing a valuable basis for developing effective strategies to mitigate plastic pollution.

Bisphenol A (BPA) is being phased out owing to its endocrine-disrupting effects and is increasingly being replaced by its substitute compounds such as bisphenol AF (BPAF). This study aims to explore the potential adverse outcomes of prenatal BPAF exposure combined with postnatal cross-fostering on the development and long-term health effects of the mammary gland in offspring. The results suggested that prenatal BPAF exposure accelerates the puberty, and induces duct dilatations, angiogenesis, lobular hyperplasia, and enhanced inflammatory cell infiltration in the mammary gland of female offspring. Differentially expressed genes exhibiting time series patterns induced by BPAF exposure were enriched in biological processes related to mammary gland development, epithelial cell proliferation and so on. Notably, 13 breast cancer-related biomarkers including Pgr, Gata3, Egfr and Areg were screened, showing a time-dependent increase in expression. After human homologous gene transformation, TCGA analysis suggested that the human homologues of genes differentially expressed in BPAF-treated mice were associated with increased tumor stages in female patients with breast cancer. Furthermore, postnatal cross-fostering did not completely restore the adverse effects of prenatal BPAF exposure and even showed a reverse tendency. These results imply that prenatal BPAF exposure in utero and postnatally nursing by BPAF exposed dams, have long-term effects on the mammary glands health of female offspring.

Efficient removal of ammonia nitrogen and sulfamethoxazole (SMX) from wastewater has become increasingly critical due to their detrimental effects on aquatic ecosystems and public health. This study aimed to investigate the nitrogen transformation and SMX removal in a membrane aerated biofilm reactor (MABR) under different SMX concentrations (0-200 μg L^-1) with a nitrifying membrane bioreactor (MBR) as a control. Results suggested that SMX removal in MABR was better than that of MBR with SMX addition (50-200 μg L^-1). Membrane aerated biofilms tended to secrete more extracellular polymeric substances (EPS) and generate less antioxidant enzymes in response to SMX stress when compared with nitrifying sludge in MBR. Metagenomic analysis indicated that distinct succession of microbial community was observed in both systems after SMX addition, and the relative abundance of nitrifying bacteria (Nitrosomonas, Nitrospira, and Nitrobacter) evidently decreased under SMX concentration of 200 μg L^-1. The proliferation of predominant antibiotic resistance gene (ARG) sul2 was suppressed more obviously in MABR than that in MBR. Thus, this study provided extensive insights into the advantages of nitrifying MABR in simultaneous removal of ammonium and antibiotics with less risk of associated ARGs spread.

The increasing role of environmental pollutants and nutrients in the development of myopia. Further longitudinal evidence is needed to elucidate the effects of early-life environmental pollutants on myopia and nutrients to protect against pollutant-induced myopia. We used mother-child dyads from the Ma'anshan Birth Cohort (n = 2028) to explore the modifying effects of maternal vitamin D status of prenatal and childhood arsenic exposure with refractive parameters and myopia. We measured serum or plasma arsenic concentrations during three trimesters, in cord blood, in childhood (5-year-old), and performed cycloplegic refraction in children aged 7-9 years (n = 1616). Primary outcomes were myopia and refractive parameters including axial length (AL), corneal radius of curvature, and spherical equivalent refraction error. Linear regression, logistic regression, and multiple informant models were performed for the association of prenatal and childhood arsenic exposure with vision health. Sex- and vitamin D status stratification analyses were also conducted. Cord serum arsenic was positively associated with AL (β = 0.15, 95%CI: 0.01, 0.29) and the risk of developing myopia (OR = 1.72, 95%CI: 1.07,， 2.75). Among boys, a 1 ng/L increase in cord serum log₁₀-transformed arsenic resulted in larger AL and a higher risk of myopia. In the vitamin D deficient group (<20 ng/mL), cord serum arsenic showed positive associations with AL (0.26 [0.06, 0.46]) and the risk of myopia (1.99 [1.01, 3.90]). Late pregnancy arsenic exposure likely affects offspring development of myopia, especially in boys. Maternal sufficient vitamin D may confer protective effects against the development of myopia.

The intensification of human activities has led to flow reduction and cut-off in most global rivers, seriously affecting riverine organisms and the biogeochemical processes. As key indicators of river ecosystems' structure and function, benthic biofilms play a critical role in driving primary production and material cycling in rivers. This research aimed to investigate the characteristics of microbial communities' complexity and stability during river flow reduction. Benthic biofilms were grown in artificial channels and subjected to eight gradients of flow reduction (represented by flow velocity from 0.4 to 110 cm/s). Biofilms' biodiversity, ecological networks and community assembly of bacteria, fungi and algae were investigated by high-throughput sequencing. Results showed significant differences in community composition and structure under different flow conditions. The eight flow gradients' microbial communities were divided into three groups: low, medium and high flows. The flow reduction led to significant decreases in bacterial and fungal communities' Chao1 index. Low flow conditions enriched the bacterial phyla Oxyphotobacteria, Alphaproteobacteria and Mollicutes, but significantly decreased the fungal phylum Chytridiomycota. Lowering flow reduced the fungal network's number of nodes and increased the algal network's number of edges. Cross-domain interactions network analysis showed a gradual increase in node and edge numbers with decreasing flow, while decreasing average path length. The neutral model predicted stochastic processes primarily drove biofilm community assembly, and that model's explanations decreased as the flow gradient decreased. The null model analysis revealed diffusion limitation as the most common stochastic ecological process for bacterial and algal communities, with reduced flow reducing heterogeneous selection and increasing diffusion-limited processes. This study provides an in-depth analysis of flow reduction's effects on biofilm communities' ecological networks and community assembly.

With the rapid progression of industrialization, the application and release of endocrine disruptors (EDCs), including bisphenol A (BPA), octylphenol and nonylphenol have significantly increased, presenting substantial health hazards. Conventional analytical techniques, such as high-performance liquid chromatography and gas chromatography-mass spectrometry, are highly sophisticated but suffer from complex procedures and high costs. To overcome these limitations, this study introduces an innovative spectral methodology for the simultaneous detection of multiple aquatic multicomponent EDCs. By leveraging chemical machine vision, specifically with convolutional neural network (CNN) models, we employed a long-path holographic spectrometer for rapid, cost-effective identification of BPA, 4-tert-octylphenol, and 4-nonylphenol in aqueous samples. The CNN, refined with the ResNet-50 architecture, demonstrated superior predictive performance, achieving detection limits as low as 3.34, 3.71 and 4.36 μg/L, respectively. The sensitivity and quantification capability of our approach were confirmed through the analysis of spectral image Euclidean distances, while its universality and resistance properties were validated by assessments of environmental samples. This technology offers significantly advantages over conventional techniques in terms of efficiency and cost, offering a novel solution for EDC monitoring in aquatic environments. The implications of this research extend beyond improved detection speed and cost reduction, presenting new methodologies for analyzing complex chemical systems and contributing to environmental protection and public health.

A notable greening and warming of the Arctic and Subarctic due to climate change has uncertain implications for the global cycling of mercury (Hg). Snowpacks are dynamic reservoirs for Hg susceptible to solar radiation and wind pumping, with vegetative cover potentially altering Hg photochemistry. However, the impact of northern greening on the transformation of major Hg species and on Hg stocks remain poorly understood. Temporal surface snow and snowpit sampling was conducted under tree canopies and open tundra sites at the boreal-tundra ecotone in Nunavik, Canada. Maximum (mean) concentrations of 69.1 ng/L (8.8 ng/L) total mercury (HgT) and 46.9 ng/L (5.5 ng/L) reactive mercury (HgR) were measured in forest surface snow, with maximums attributed to rapid atmospheric oxidation events. Significant post-depositional reductions were recorded in the bay, tundra, and forest (67-99% HgR) and suggested greater Hg sequestration may occur under tree canopies. Increasing methylmercury (MeHg), HgT, and dissolved organic carbon (DOC) concentrations were detected across a vegetation gradient shifting towards humic-like organic matter. Notably, springtime depth profiles presented an approximate 12-fold greater accumulation of HgT under tree canopies compared to open tundra (p < 0.01), with up to 16-times higher stocks (HgT, MeHg, DOC) at elevated vegetation density (p < 0.05). In the North, increasing vegetation cover and surface warming may favor Hg accumulation and methylation in snowpacks, facilitated by interactions with organic matter, and further enriched by the reduced wind and solar exposure experienced under forest canopies.

Agricultural organic wastes can leach dissolved organic matter (DOM) into surrounding water bodies, establishing them as significant sources of aquatic DOM. Given the importance of DOM in biogeochemical cycling of mercury (Hg), this DOM may mediate divalent Hg (Hg(II)) reduction, a process that remains poorly understood. This study investigated Hg(II) reduction using DOM derived from six representative agricultural wastes, categorized into livestock manure (chicken, pig, cow) and crop straw (rice, corn, rapeseed), with systematic considerations of the kinetics of reduction processes and the involvement of key free radicals. Results revealed that photoreduction was the primary pathway for Hg(II) reduction, with pig manure DOM exhibiting the highest efficiency at 36%. Key DOM quality parameters, such as protein-like components, have been identified as critical determinants of Hg(II) photoreduction capacity. Furthermore, free radicals induced by DOM could either enhance or inhibit Hg(II) reduction capacities. Specifically, in livestock manure, the superoxide anion (O₂^•-)·was identified as the primary radical promoting Hg(II) photoreduction of pig manure DOM. In crop straw, hydroxyl radicals (·OH) were found to inhibit Hg(II) photoreduction, whereas O₂^•- promoted the Hg(II) photoreduction of rice straw DOM. These findings provide valuable insights into the role of agricultural organic wastes in biogeochemical cycling of Hg within aquatic ecosystems.

Char materials (e.g., hydrochar) can enhance carbon sequestration, improve soil quality and modulate soil microbial communities to recuperate soil health. However, little is known about the soil organic carbon (SOC) content, as well as the microbial communities and co-occurrence networks in response to hydrochar amendment in an inshore saline soil. Here, the effect of Sesbania cannabina (a halophyte) straw derived hydrochar (SHC) amendment on SOC and labile organic carbon (LOC) fractions and the potential associations among SOC content change, soil C-cycling enzyme activities and microbial communities were illustrated using a pot experiment. SHC effectively improved the contents of SOC and LOC, particularly particulate organic carbon (POC), and stimulated the activities of C-cycling enzymes. Furthermore, SHC induced shift in microbial community compositions and co-occurrence networks, result in decrease in relative abundance of Actinobacteriota and its corresponding ecological cluster, which may favor SOC accumulation. Functional annotation of prokaryotic taxa (FAPROTAX) analysis also revealed a decrease in microbial ecological function related to carbon degradation. These findings provided a deeper insight about the hydrochar-induced SOC enhancement and suggested an efficient approach to improve C sequestration and improve soil health in the coastal salt-affected soil.

Integrating photocatalysis with electrocatalysis may represent a synergistic approach to address environmental and energy challenges. In this context, we explored synthesizing a series of nanocomposite materials using a solid-state approach involving simple grinding and subsequent thermal treatment for the photocatalytic purification of dinoseb and electrocatalytic oxygen evolution (OER). Interestingly, among the series of synthesized materials, 40 wt percentage of 3D/2D/1D:ZnFe₂O₄/NiAl-LDH/MWCNTs ternary nanocomposite (40-NZM) showed highly improved dinoseb detoxification and OER efficiencies compared to those of pure materials. Importantly, approximately 98% detoxification of dinoseb was observed within 75 min of irradiation time under a visible light source. Remarkably, the 40-NZM nanocomposite exhibited the highest rate constant value (k = 4.1 × 10^-2 min^-1) with a favorable R² (0.98) parameter. Furthermore, 40-NZM showed promising electrocatalytic OER performance, requiring only 217 mV of overpotential to achieve 10 mAcm^-2 of current density with a smaller Tafel slope of 66.6 mVdec^-1. Additionally, long-term stability was tested by recording 2000 cyclic voltammetry (CV) cycles. The results revealed that 40-NZM could maintain its catalytic activity for a longer duration as it required only 227 mV to attain 10 mAcm^-2 even after 2000 CV cycles. Consequently, these outstanding characteristics of 40-NZM nanocomposite underscore the significant potential for catalytic water purification and sustainable energy conversion.