Environmental Research最新文献

The electrocatalytic reduction of nitrate to ammonia (NRA) technology not only achieves the effective removal of nitrates in the environment but also produces value-added products-NH₃. In recent years, copper-based materials have shown tremendous application prospects in this field due to their excellent conductivity, moderate cost, and their proximity of d orbital energy levels to the LUMO π∗ molecular orbitals of nitrate. This review starts with copper-based catalysts to elucidate the reaction mechanisms of NRA and its influencing factors, while summarizing and analyzing the principles and pros and cons of various modification strategies. Then, we will explore the impact of different modification strategies on improving NRA performance and the underlying theoretical mechanisms. Finally, this review proposes the current challenges and prospects of copper-based materials, aiming to provide a reference for the further development and industrial application of copper-based catalysts.

The widespread use of personal care products (PCPs) and subsequent exposure to their volatile methylsiloxane (VMS) content are often overlooked worldwide. Moreover, regulatory measures addressing VMS levels are sparse, and research on VMS levels in PCPs is limited. Therefore in this study, 141 PCPs from Korea, one of the biggest PCP markets in the world, were extracted and analyzed for seven VMSs using gas chromatography-mass spectrometry. Overall, cyclic VMS (cVMS) compounds were found at higher concentrations than linear VMS (lVMS) compounds, accounting for more than 93% of the total VMS concentration. The highest VMS content in PCPs was observed for octamethylcyclotetrasiloxane (D4) and hexamethylcyclotrisiloxane (D3), at approximately 130,000 and 110,000 μg g^-1, respectively. Additionally, the total VMS (∑VMS) concentration were in the order of face > hair > body products. PCPs were classified as non-rinse or rinse products based on their retention time on the body of the consumer. Non-rinse body products had more than twelve times the ∑VMS content of rinse body products (341 and 26.8 μg g^-1). Rinse hair products are three times the ∑VMS content of non-rinse hair products (576 and 191 μg g^-1). Furthermore, the principal component analysis suggested that PCPs can be grouped according to their cVMS content, with D3 and decamethylcyclopenatsiloxane (D5), D4, and D5 co-occurring. Notably, daily dermal exposure to VMSs in PCPs was largely determined by the retention time of the PCP on the body, followed by the VMS concentration. Although exposures to cVMS compounds were generally higher, exposure to the lVMS content of some PCPs was higher depending on the product type. Therefore, it is crucial to consider the significance of all VMS compounds, not solely cVMS, in exposure calculation and regulations. This study provides a database for regulatory bodies to implement in their exposure and toxicity studies.

Microalgae-bacterial granular sludge (MBGS) process has great potential in achieving carbon neutrality and energy neutrality, but rapidly cultivating MBGS remains challenging. To address this challenge, this study proposes a new strategy to develop MBGS systems using pre-made granules from microalgae and dewatered sludge. The results indicate that using pre-made microalgae-dewatered sludge granules (M-DSG) as inoculants can directly develop MBGS system, with M-DSG maintaining a relatively stable granular structure, and ultimately achieving pollutant removal efficiencies of 94.0% for chemical oxygen demand (COD), 99.7% for ammonium nitrogen (NH₄⁺-N), and 86.0% for total inorganic nitrogen (TIN). Extracellular polymeric substances (EPS) play a dominant role in maintaining the structure of granules, while filamentous bacteria/algae provide additional reinforcement. The adhesion of microalgae to granules possibly relies on polysaccharides in tightly bound extracellular polymeric substances (TB-EPS) and proteins in loosely bound extracellular polymeric substances (LB-EPS). Microbial community analysis reveals that the target algae (Chlorella) remain the primary algae, and heterotrophic nitrifying bacteria (HNB) and denitrifying bacteria are enriched.

Background & aim: Understanding local vulnerability to heat and cold is crucial for public health planning, yet few studies have provided a nationwide analysis of temperature-related mortality across diverse communities. This study analyses the association between ambient air temperature and non-accidental mortality across mainland Norway, using a constrained hierarchical clustering algorithm to group municipalities with similar geographic, environmental, socioeconomic, and demographic patterns.

Methods: This study analysed the association between ambient air temperature and non-accidental mortality across 356 Norwegian municipalities, using daily data from 1996 to 2018. We applied a case time series design with distributed lag non-linear models. A downscaling procedure assessed the effect of 21 vulnerability factors on temperature-related mortality risks, using Principal Components Analysis to explore heterogeneity across clusters.

Findings: Cold temperatures contributed to an estimated 3879 deaths per year (95% CI 3718-4130), while heat was associated with 44 deaths annually (95%CI: 29-58). The highest heat-related mortality risk occurred in the South-East, and the highest cold-related risk in the Central-East. Greater heat-related mortality correlated with medium-to sparsely-populated areas, while higher education levels were linked to reduced vulnerability to both heat and cold.

Interpretation: By providing the first comprehensive assessment of temperature-related excess mortality and associated risk factors in Norway, our findings underscore the need for targeted, equitable health policies that integrate environmental and socioeconomic factors. These insights are essential to guide climate adaptation strategies, prioritising vulnerable rural communities and socioeconomically disadvantaged groups to mitigate future climate-related health impacts.

The toxic dyeing wastewater containing both carcinogenic Cr(VI) and refractory dyes poses serious threats to ecological safety and human health. Herein, a novel composite photocatalytic material e-LDH/t-BiOCl/Bi₂S₃ with an ultrathin sandwich structure constructed achieves removal rate constants of 0.044 and 0.019 min^-1 for Cr(VI) and reactive red 2 by adsorption-photocatalysis synergistic mechanism in full-spectrum illumination. This structure employs the interface conditions and built-in electric field to form multilevel short-range charge migration channel, achieving the targeted reduction and oxidation of Cr(VI) and azoxy dyes by electrons (e^-) and holes (h⁺). Besides facilitating the reduction of Cr(VI), e^- can also enhance the effective utilization of h⁺ and mediate the formation of other reactive oxygen species that target RR2 degradation. The degradation mechanism, pathway, and biological toxicity of RR2 single and Cr(VI)/RR2 coexistence reaction system were discussed by DFT calculation, LC-MS characterization, and T.E.S.T. evaluation. Moreover, we further investigated the photocatalytic activity and cost-effectiveness of the e-LDH/t-BiOCl/Bi₂S₃ system under continuous flow and real water settings, and determined the primary water quality parameters that influence photocatalytic performance. This work establishes a new concept for the rational design of robust ternary heterostructure photocatalysts with desirable morphology and competitive performance for photocatalytic applications.

Habitat discontinuity of aquatic environments is a serious problem that might hamper the different activities performed by organisms. When combined with contamination, the consequences for the population's dynamics might be exacerbated, particularly regarding foraging activity. Therefore, the aim of this study was to evaluate the combined effects of habitat discontinuity and contamination on the foraging behavior by zebrafish (Danio rerio) and on their ability to explore heterogeneous landscapes. The organisms were exposed to three different scenarios of contamination (0, 0.5 and 25 μg L^-1 of Cu) and habitat discontinuity (zero, low and high), using the Heterogeneous Multi-Habitat Assay System (HeMHAS). Generalized Bayesian linear models were used to analyze the data and evidence ratios (ER) were used to test the hypotheses. As results, both high levels of contamination and habitat discontinuity had significant effects on the probability of organisms to reach food (ER = 111.8 and > 1,000, respectively), the time taken to reach food (ER = 532.22 and > 1000, respectively) and the time spent in each compartment (ER = 614.4 and > 1000 for contamination and the number of connections available, respectively). As conclusion, the habitat fragmentation as a consequence of contamination and discontinuity affected the probability of fish to reach food and the time spent to reach it. This could lead to additional energy budget with serious consequences for population dynamics. Also, the HeMHAS demonstrated its suitability to assess the role of the contamination and habitat connectivity stressors in the spatial distribution and habitat selection response.

Contaminants released into the atmosphere that undergo regional and long-range transport can deposit back to Earth through snowfall. When snow melts, these contaminants re-enter the environment, sometimes far from their original emission sources. Here we present the first comprehensive characterization of organic contaminants in snow from North America. Fresh snowfall samples were collected in the central United States over a three-year period and measured by liquid chromatography high-resolution mass spectrometry for suspect screening and non-targeted analysis. The resulting data set was screened against experimental MS/MS libraries and underwent supplemental in silico MS/MS analysis. In total, 91 possible compounds were tentatively identified in snow, and 17 were successfully confirmed and semi-quantified with reference standards. These contaminants were mostly anthropogenic in origin and included six herbicides, three insect repellants, one insecticide metabolite, and one fungicide. The most prominent compounds present in all samples were N-cyclohexylformamide (known contaminant in tire leachate), DEET (insect repellent), and dimethyl phthalate (plasticizer), with median deposition fluxes of 4032, 284, and 262 ng m^-2, respectively. Three additional compounds were detected in 100% of samples: coumarin (phytochemical and fragrance additive), 5-methylbenzotriazole (antifreeze component), and quinoline (heterocyclic aromatic). The Peto-Peto test revealed statistically significant differences in deposition fluxes for these six contaminants (p < 0.05), with weak but statistically significant positive associations between coumarin and DEET and between coumarin and quinoline according to a Kendall's tau correlation analysis. These findings demonstrate the utility of in silico analysis to complement MS/MS matching with experimental databases. Even so, thousands of unidentified features remained in the data set, highlighting the limitations of current strategies in non-targeted analysis of environmental samples.

The development of adsorbent and/or photocatalysts based on covalent triazine frameworks (CTF) is fascinating research due to their structural properties, functional groups, and active sites. Herein, a CTF-TiO₂ heterojunction was synthesized by modifying CTF sheets with TiO₂ particles through wet impregnation technique and adsorptive and photocatalytic activities determined for ciprofloxacin (CIP) removal. Comprehensive characterisation of the composites revealed suitable properties of the composites, such as sandwich-like CTF-TiO₂ morphology, improved thermal stability, and better heteroatom effect (HAE). The adsorption capacity of CTF-TiO₂-1 (CT-1) and CTF-TiO₂-2 (CT-2) reached 30.30 mg g^-1 and 13.61 mg g^-1, respectively. Meanwhile, the CT-2/H₂O₂ system, compared to all other materials, achieved a better degradation efficiency of 90.7 % within 40 min compared to 77.5 % observed in using only CT-2 for 120 min. In addition, scavenging results suggested that e^- and h⁺ was crucial for the effective degradation of CIP. Identification of the degradation product of CIP suggests hydroxylation, decarboxylation, and opening of the quinolone and piperazine ring as possible degradation pathways. The mineralization of CIP was 90.93 % for the CT-2/H₂O₂ system and its stability maintained for four cycles. The outstanding performance of CT-2 is attributed to its enhanced band gap energy of 2.86 eV, and reduced recombination rate of photogenerated electrons and holes. These results prove these materials are efficient adsorbent/photocatalyst in CIP removal from solution.

The ecological security of lakes in arid areas is crucial for the sustainable development of regional society and the economy. The threat of dry lake-bottom dust and degradation of vegetation around lakes has become increasingly significant. This study proposes the maintenance of an optimal water surface area to ensure the ecological safety goals of Ebinur Lake. The study also conducts a scenario analysis of the amount of water entering the lake. Utilizing a Systeme Hydrologique Europeen (MIKE SHE) watershed model with four different inflow scenarios, the study simulated the Ebinur Lake's area changes under various water replenishment scenarios. Replenishment scenarios that meet the ecological security goals were selected for this study. The results indicate that maintaining a lake surface area of 710 km² or more during warm season can prevent wind and sand fixation, while a lake surface area of no less than 500 km² during dry season may help maintain ecological security. To ensure ecological security during dry years, the Kuitun River should annually replenish the Ebinur Lake with 1.75 × 10⁸ m³. These findings provide valuable insights a practical tool for the ecological restoration and management of lakes in arid areas.

Ionizing radiation (IR) represents a significant risk to human health and societal stability. To effectively analyze the mechanisms of IR and enhance protective strategies, the development of more sophisticated animal models is imperative. The zebrafish, with its high degree of genomic homology to humans and the capacity for whole-body optical visualization and high-throughput screening, represents an invaluable model for the study of IR. This review examines the benefits of utilizing zebrafish as a model organism for research on IR, emphasizing recent advancements and applications. It presents a comprehensive overview of the methodologies for establishing IR models in zebrafish, addresses current challenges, and discusses future development trends. This paper provide theoretical support for elucidating the mechanisms of IR injury and developing effective treatment strategies.