Environmental Science and Pollution Research最新文献

Indoor air pollution caused by fine particulate matter (PM_2.5) can be mitigated by indoor ornamental plants, however phytoremediation efficiency is limited by stress-induced declines in plant function. Biogenic volatile organic compounds (BVOCs) are known to mediate plant-plant communication and induce stress resistance, but their role in PM_2.5 tolerance remains unexplored. Here, we investigated whether BVOCs enhance plant tolerance and PM_2.5 removal efficiency from cigarette smoke in Episcia cupreata (Gesneriaceae). Plants exposed to PM_2.5 exhibited reduced photosynthetic pigments and elevated malondialdehyde (MDA), indicating oxidative stress. PM_2.5-stressed plants emitted distinct BVOCs profiles particularly monoterpenes, with limonene increasing 6.1-fold and eucalyptol 1.7-fold. Exogenous application of these volatiles demonstrated dose-dependent effects: optimal concentrations (25 ppm) significantly accelerated PM_2.5 removal, mitigated oxidative damage, and maintained chlorophyll and carotenoid levels compared to non-primed controls. Metabolomics revealed that volatile monoterpenes priming upregulated zeatin biosynthesis, arginine and proline metabolism, supporting cytokinin and osmoprotectants biosynthesis to prepare for PM_2.5 stress. Together, these findings demonstrate that, in E. cupreata, limonene and eucalyptol act as airborne chemical signals that enhance PM_2.5 phytoremediation capacity under cigarette smoke conditions by mitigating oxidative stress and promoting osmoprotection. This study provides the first evidence of BVOC-mediated enhancement of PM_2.5 removal by plants, suggesting that volatile monoterpenes priming is a promising strategy for improving indoor PM_2.5 pollution mitigation using plant-based systems.

This study investigates the fresh properties of self-compacting concrete (SCC) developed using recycled concrete aggregates (RCA) as coarse aggregate replacement and ground granulated blast-furnace slag (GGBS) as cement replacement. This study employs an integrated statistical framework to simultaneously analyze, interpret, and optimize multiple SCC fresh performance parameters. SCC mixes were prepared with 15% to 45% GGBS and 20% to 100% RCA, and their fresh properties were evaluated through slump flow, T₅₀₀, J-ring, V-funnel, L-box, and U-box tests. Microstructural and chemical characterization of the raw materials was conducted using scanning electron microscopy (SEM) and X-ray fluorescence (XRF) to assess morphology and compositional compatibility before evaluating the fresh properties of SCC. Results showed that workability decreased with increasing RCA but improved with GGBS by up to 30% due to enhanced paste volume and reduced internal friction. Regression analyses revealed strong correlations between key fresh property parameters, such as slump flow and T₅₀₀ (R² = 0.971), J-ring and V-funnel (R² = 0.880), and L-box and U-box (R² = 0.947). A two-way ANOVA confirmed that GGBS and RCA have a statistically significant effect on fresh properties (p < 0.001). Furthermore, response surface methodology (RSM) to identify optimal mix proportions and principal component analysis (PCA) to explore the underlying structure of the test methods were also performed. The results indicate that a mix with 30% GGBS and 60% RCA provides optimal fresh properties, confirmed by PCA and regression analyses. These findings provide a practical framework for designing sustainable SCC mixtures using construction and industrial waste materials, enabling engineers to balance workability, passing ability, and sustainability requirements in real-world construction applications.

Male factor subfertility is a significant public health issue and contributes substantially to the overall burden of infertility. The present study evaluated environmental and lifestyle exposures among male partners of infertile couples across India, estimated the proportion of male factor subfertility, and examined associated semen parameter abnormalities. This multicentric, cross-sectional study involved male partners of infertile couples presenting to 17 tertiary centres across India. Socio-demographic, occupational, lifestyle, and clinical data were collected using structured questionnaires and clinical examinations. Semen analysis was performed according to the WHO-2021 guidelines. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors. Among 2414 infertile couples, 77.5% had primary infertility and 22.5% secondary infertility. Male factor subfertility accounted for 27.3% of cases, female factor 36.9%, combined factors 9.7%, and unexplained infertility for 26.1%. Asthenozoospermia (23.4%) was the most common semen abnormality. Multivariate analysis identified urban residence (p = 0.02), semiskilled occupation (p = 0.009), lower socioeconomic status (p = 0.013), heat exposure (p = 0.002), over-the-counter drug use (p = 0.03), previous genital tract surgery (p = 0.011), and COVID-19 infection (p = 0.014) as independent predictors of abnormal semen parameters. Varicocele and congenital genital tract anomalies demonstrated increased odds of abnormal parameters but did not reach statistical significance (p = 0.067; p = 0.056, respectively). However, the increasing severity of varicocele showed a significant negative correlation with sperm concentration per mL (p = 0.001) and percentage of morphologically normal sperm (p = 0.040). Male factor subfertility in India is multifactorial, strongly influenced by modifiable environmental, lifestyle, and clinical factors.

Exposure to cleaning products may harm the lungs, mainly through inhalation of irritants and sensitising chemicals, which can induce airway inflammation and bronchial hyperresponsiveness. Given increased use of multiple cleaning products at work and home, understanding the impacts of their interplay, rather than individual exposures, is critical but has not been investigated to date. We aim to investigate the cross-sectional association between exposure to cleaning products at home and/or in the workplace and respiratory health. We conducted a cross-sectional analysis of 318 adults from the Melbourne arm of the European Community Respiratory Health Survey (ECRHS) III. Cleaning product exposure was assessed through questionnaires, categorising participant exposure into seven product groups. Latent class analysis was used to identify exposure classes. Adjusted multivariable regression modelled associations between cleaning product classes and respiratory outcomes. We identified four classes of exposure to cleaning products: "minimal users", "light users", "moderate users", "heavy users". The most exposed "heavy user group" characterised people using many different cleaning products on a weekly basis (especially bleach, sprays, polish, solvents, acids). This class was associated with increased risks of current asthma (OR, 3.24; 95% CI 1.19-8.77), and lower post-bronchodilator FEV₁ (z-score, -0.47) and FVC (-0.46) compared with "minimal users". This work used a data-driven latent class approach to capture real-world cleaning product use patterns and relate them to respiratory health. We found that frequent use of multiple cleaning products was linked to more asthma and lower lung function, suggesting potential combined effects. These findings highlight the need for cleaning product standards and asthma care guidelines to mitigate risks associated with cleaning products.

The South Eastern Arabian Sea (SEAS) along the west coast of India often shows intense aerosol build-up during the pre-monsoon season, marked by brief Aerosol Optical Depth (AOD) surges. As such events are found crucial to regional weather, this study examines the causes and effects of these events, integrating data from MODIS, CALIPSO, and INSAT-3D satellites, MERRA-2 reanalysis, and back-trajectory analysis for the period 2015-2017. High AOD events over the SEAS are linked to elevated aerosol layers between 1 and 4 km, mainly polluted dust and smoke, with pure dust in most of the cases. These events are found to be fuelled by pronounced shifts in wind circulation, increased convergence, strong updrafts, and higher humidity above ~ 1.5 km, aiding aerosol transport from upwind biomass-burning and industrial regions. Absorbing aerosols like black carbon (BC) and organic carbon (OC) strongly correlate with sulphates (SU), suggesting common origin and mixed aerosol type, pointing towards higher absorption effects. This together with the amplifying influence of underlying clouds increases the positive Atmospheric Radiative Forcing (ARF_ATM) from 4 to 6 W m⁻² on normal days to 8-12 W m⁻² during high-pollution events. This increased radiative forcing heats the lower atmosphere (0.3-2.5 km) by about 1-2 K, as seen in temperature profiles, and its changes closely follow the observed temperature variations. These exciting observational results highlight the strong role of absorbing aerosols in high pollution events modifying the atmospheric thermal structure, with probable implications on aerosol-cloud-precipitation interactions and weather patterns along the west coast of India.

This study presents a transformative zero-waste paradigm for up-cycling steel slag (SS) which is an abundant industrial waste, by strategically deconstructing it into two valuable products. The established process involves the targeted sulfuric acid leaching of SS to separate its major components: iron ions and calcium. The iron-rich leachate serves as a precursor for the plant-mediated synthesis of α-Fe₂O₃/SiO₂ nanocomposites using Gingko biloba leaf extract, while the solid residue is transformed into gypsum (CaSO₄·2H₂O), a huge applicable material in construction and agriculture. Optimization of methylene blue (MB) adsorption using the Taguchi method achieved an experimental equilibrium capacity of 37.03 mg/g under the investigated conditions. The adsorption behavior was best described by the pseudo-second-order kinetic model and the Freundlich isotherm model, indicating dominant chemisorption on a heterogeneous surface. The Freundlich constants (K_F = 75.5 (mg/g)(L/mg)^1/n and n = 2.04) confirmed strong adsorption affinity and favorable adsorption characteristics. A Langmuir monolayer capacity of 102.04 mg/g was estimated from model fitting. Density functional theory (DFT) and molecular mechanics simulations provided atomistic-level confirmation of a strong, exothermic interaction between methylene blue (MB) and the Fe₂O₃ surface, albeit moderated in an aqueous environment. Furthermore, the nanocomposite showed remarkable stability, retaining over 70% of its removal efficiency after five consecutive adsorption-desorption cycles. This study establishes a comprehensive "waste-to-wealth" pipeline beyond simple waste modification and demonstrates a viable circular economy model simultaneously designed to control the solid waste management and water pollution.

Membrane-based approach is a very effective method for water purification, but fouling is still a major obstacle that limits its performance. In this study, a self-cleaning GO/g-C₃N₄/ZnO composite membrane was developed to improve the fouling resistance by utilizing the structural stability of g-C₃N₄ and the photocatalytic properties of ZnO (band gap 3.2 eV). GO was synthesized via a modified Hummer method, while g-C₃N₄ was obtained via a calcination process. The membranes were prepared using vacuum filtration on nylon support with varying ZnO concentrations (5-25%) and maleic anhydride as a cross-linker to enhance the membrane stability. FTIR, XRD, UV-Vis DRS, PL, and SEM-EDX characterizations confirmed the successful synthesis of the composite with homogeneous distribution of C, O, N, and Zn on the membrane surface. The naphthol blue black filtration test showed the separation efficiency up to 99.9%. The GO/g-C₃N₄/17.5.ZnO membrane exhibited the highest permeability in the first cycle at 70.6 L m^-2·h^-1·bar^-1, while the GO/g-C₃N₄/15.ZnO membrane demonstrated the best stability, maintaining a 93% rejection efficiency after four usage cycles. Long-term cross-flow filtration under periodic UV light irradiation further confirmed stable rejection (~ 99%) over 20 h, highlighting the effective self-cleaning capability of the membrane. These results demonstrate that the GO/g-C₃N₄/ZnO composite membrane is a promising candidate for durable, self-cleaning water filtration applications.