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Naphthols (NAPs), commonly used phenolic compounds, have significant impact on environmental risk and human health, necessitating advanced treatment methods for their degradation. In this study, a Ti 4 O 7 reactive electrochemical membrane (REM) was developed for the electrochemical oxidation of NAPs. The Ti 4 O 7 REM presented a porosity of 42.18 ± 2.3% and a median pore diameter of 1.21 µm. High permeability (846 LMH bar−1) was achieved at relatively low transmembrane pressure and resulted in a convection-enhanced rate constant for Fe (CN) 6 4- oxidation of 1.7 × 10−4 m/s. The increase in current density and decrease in plate spacing had a positive influence on NAPs degradation. The TOC removal efficiencies of 1-naphthol (1-NAP) and 2-naphthol (2-NAP) were 68.6% and 63.5%, respectively at the current density of 6 mA/cm2 and plate spacing of 10 mm. Additionally, quantum chemical calculation using density functional theory (DFT) was employed to identify the active sites of NAPs through atom charge and frontier electron density (FED) calculations. Results showed that C14 and C10 were identified as the active sites for 1-NAP, while C9 and C13 were the active sites for 2-NAP. Hydroxyl radical and sulfate radical produced on the electrode surface were the main oxidants for NAPs degradation during the electro-oxidation process. The degradation pathway included hydroxylation, oxygenation, decarbonylation, and ring-open processes, which was in agreement with the theoretical calculations. Furthermore, the quantitative structure-activity relationship (QSAR) predictive model was used to assess the toxicity changes during the electrochemical oxidation process of NAPs, suggesting that the toxicity of intermediates increased at the beginning and significantly reduced at the end. This comprehensive study provides practical and theoretical insights into the application of electrochemical oxidation technique for the reduction of refractory compounds in wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal exposure is suspected to be associated with the risk of chronic kidney disease (CKD). Copper (Cu) is an essential yet toxic trace element in humans. Epidemiological evidence on the association of Cu exposure with CKD remains inconsistent. This study aims to investigate the association of blood Cu and its co-exposure to other metals with CKD. A cross-sectional study was conducted among 3285 older participants in Zhejiang, China. The whole blood levels of Cu as well as other 10 metals were measured using the inductively coupled plasma mass spectrometry (ICP-MS). CKD events were defined as the presence of albuminuria or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. Multivariable logistic regression and linear regression models were applied to assess the association of Cu with kidney function. The Bayesian kernel machine regression (BKMR) was used to examine the association of metal interactions with CKD. In logistic models, we found a dose-dependent positive association between blood Cu and the prevalence of CKD. Compared to the lowest quartile of blood Cu, the odds ratio (OR) of CKD in the highest quartile was 1.65 (95% confidence interval, CI: 1.25, 2.17), and the β of eGFR was −1.74 (95% CI: −3.15, −0.34) after adjusting for multiple covariates. The positive linear dose–response association was found between blood Cu and the OR of CKD, and negative linear association was found between Cu and the β of eGFR. The positive association between blood Cu and CKD risk was stronger at lower level of manganese (Mn) in the BKMR model. The whole blood level of Cu was remarkably associated with the risk of CKD and showed positive dose–response relationships in the older Chinese population. The toxicity of Cu on kidney function could be antagonized by the exposure of Mn. These findings shed new light on the potential role of Cu in kidney health. [ABSTRACT FROM AUTHOR]

How to predict the efficacy of heterogeneous catalytic ozonation reactors in reducing pollutants remains limited by complex multiphase systems. An integrated mathematical model of catalytic ozonation by activated carbon (AC) was developed based on hydrodynamics, mass transfer, adsorption, and reaction kinetics to simulate the performance of gas-liquid continuous flow catalytic ozonation reactors. A novel method was proposed reflecting the catalyst behavior to transform the complex gas-liquid-solid multiphase catalytic system into mass conservation equations for each component in gas and liquid phases. The catalyst activity is assumed to be mainly represented by adsorption and the transformation of ozone to hydroxyl radicals (•OH) by active groups on catalyst surface. A mathematical formulation of •OH generation was derived based on the Langmuir-Hinshelwood (LH) mechanism. The model simulation results obtained the concentration profiles of each component and achieved a satisfactory predictive power with error less than 20%, which in turn justified the modeling process. Sensitivity analysis showed that parameters including gas-liquid mass transfer coefficient, secondary reaction rate constant for indirect oxidation and catalyst capacity transfer coefficient have greater influence on simulation results. The optimal conditions for ozone utilization and pollutant degradation were obtained using the validated model simulations: catalyst dosage of 5 g/L, gas flow rate of 0.05 L/min, and initial ozone concentration of 50 mg/L. The results suggest that this mathematical model can provide useful information for design and optimization of catalytic ozonation reactors during industrial applications. [ABSTRACT FROM AUTHOR]

China, as the largest global emitter of atmospheric polycyclic aromatic hydrocarbons (PAHs), exhibits significant variation in energy structure and technological capabilities among provinces. It is vital to construct a provincial-level emission inventory of PAHs, fully considering these provincial disparities, for assessing the environmental budgets and instituting effective mitigation measures. This study constructed a dataset of provincial PAHs emission factors based on downscaling estimates by incorporating the Human Development Index (HDI). These emission factors were combined with the latest activity rate data to estimate PAHs emissions from individual provinces in China from 2007 to 2017. The national total PAHs emissions in our study were 11.8–12.3% higher than the previous emission inventory results. The validation results indicated that the inventory-based PAHs emissions were significantly correlated with the simulated emissions by an atmospheric box model and watershed model. From 2007 to 2017, nearly three-quarters of provinces declined in PAHs emissions resulting from technological advancements and environmental standard improvements, leading to a 34.4% reduction (from 118.5 to 77.8 Gg) of the national total. The industrial sector was consistently the dominant contributor (51.9–66.4%) with a growing trend in its share. This growth was dominantly contributed by less developed provinces, such as Heilongjiang, Ningxia, and Qinghai, indicating that there was a shift of industrial sectors and associated PAHs emissions from highly concentrated industrial regions to nascent industrial regions. This study provides essential data support for a comprehensive understanding of each province's emission responsibilities regarding PAHs and for assessing the potential risks that PAHs pose to human health and ecosystems in these provinces. [Display omitted] • Multi proxies-based modeling for updating PAH provincial emission inventory. • National PAHs emissions were 11.8–12.3% higher than previous emission inventories. • PAH emissions from coking source was much lower in traditional coal and iron and steel provinces. • Most provinces declined in PAHs emissions causing a 34.4% reduction of the national total. • Industrial sectors in less developed provinces showed an increase in PAH emissions. [ABSTRACT FROM AUTHOR]

Organic pollutants in water could be removed by electrochemical treatment using a reactive electrochemical membrane (REM) with Magnéli phase Ti 4 O 7 , yet it is challenging to design suitable porosity to realize effective mass transfer and enhance the reactivity. Here, a novel Ti 4 O 7 REM was prepared by a spark plasma sintering (SPS) method, which showed excellent electrochemical reactivity and mass transfer rate for organic pollutants in water. Compared to other Ti 4 O 7 REMs, the novel Ti 4 O 7 REM achieved a 140–9000-fold decrease in charge transfer resistance and a 5–110-fold increase in mass transfer rate. The p-nitrophenol in water can be completely removed in the REM system, with a maximum total organic carbon (TOC) removal rate of 85%. Then the REM system obtained an amazing removal rate of TOC (50.1%) and UV 254 (89.6%) in the electrochemical treatment of real coking wastewater. In addition, to further enhance the removal efficiency, a coupled oxidation process with the novel Ti 4 O 7 REM and O 3 aeration was investigated. The TOC removal rate and energy consumption were 57.1% and 165.2 kWh (kg TOC)−1 at the optimal conditions within a short treating time. Our findings highlighted an innovative REM for a broad range of potential environmental applications. • A Ti 4 O 7 reactive electrochemical membrane (REM) was fabricated by the spark plasma sintering (SPS) technology (REM-SPS). • The REM-SPS increased the mass transfer rate significantly. • The REM-SPS showed excellent conductivity and reactivity in the utilization of water purification. • The electrochemical + ozonation process enhanced the removal efficiencies and decreased the energy consumption. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) emissions driven by transboundary supply-chain activities across Chinese provinces are largely unknown. In this study, we comprehensively assessed the dynamics of production-, consumption-, and income-based PAHs emissions from individual Chinese provinces in China from 2007 to 2017. We also examined the critical supply-chain paths and socioeconomic drivers behind the changes in PAHs emissions and explored their correlations with China's economic restructuring during this period. We found that production-, consumption-, and income-based PAHs emissions have decreased to lower levels in 2017 (45.6, 36.2, and 40.1 kt, respectively) than those (52.8, 37.5, and 43.6 kt, respectively) in 2007. The dominant contributors of trade-driven PAHs emissions were located in the northern inland provinces with rich coal resources and the southeastern coastal provinces with dense populations and developed economies. China's economic restructuring reduced PAHs emissions in these provinces in the post-global financial crisis era, benefiting from improvements in emission intensity and trade structure. Concurrently, migrating energy- and emission-intensive industries into less affluent provinces (e.g., Xinjiang, Jiangxi, Henan, Anhui, and Yunnan) changed the roles of emission factors (from the demand side), primary input structure and energy mix (from the supply side) from driving down to driving up PAHs emissions. These changing drivers exerted a greater upward influence on PAHs emissions than the overall downward influence exerted by other drivers, thereby causing emissions outsourcing and leakage. This study explored the effects of economic structural transition on interprovincial trade-driven PAH emission transfer, offering valuable insights for policymakers to formulate policies for mitigating PAHs emissions. [Display omitted] • Provincial PAHs emissions embodied in domestic trade in China were estimated. • Production-, consumption-, and income-based emissions substantially overlap with each other. • Final demands of southeast coastal provinces drive PAHs emissions from coal-rich provinces. • Economic restructuring contributes to the national total declining emissions after 2012. • Emission factor and energy mix drive emissions in less affluent provinces in post crisis era. [ABSTRACT FROM AUTHOR]

Abstract Background Air pollution epidemiological studies increasingly rely on high-resolution exposure prediction models. However, to date, few models of this type exist for use in China. Objectives We produced a national land-use regression model (LUR) to estimate monthly average PM 2.5 , PM 10 and NO 2 from 2014 to 2016 in China. Methods We developed a spatiotemporal semi-parametric model using generalized additive mixed models. A variety of predictor variables were included in model: time varying meteorological data, high resolution land cover data from Globaland30, satellite measures of aerosol optical depth, and Geographic Information System (GIS)-derived predictors. We assessed model performance with two cross-validation (CV) approaches, including hold-out CV, and 10-fold CV. Results Over 22,000 monthly observations at 1382 monitoring locations were included to estimate the air pollution exposure. The time-varying spatial terms explained 87%, 71%, and 69% of variability with a hold-out cross-validated R2 of 0.85, 0.62, and 0.62 for PM 2.5 , PM 10 and NO 2 models, respectively. Models show that meteorological variables, population density, elevation, distance to road, and land cover types were important predictors for air pollution exposure. Conclusions we have developed a new nationwide model to estimate residence-level air pollution exposures, which can be used in studies of the chronic adverse effects of air pollution. Highlights • We developed national scale spatiotemporal land use models to estimate monthly PM 2.5 , PM 10 and NO 2 concentrations in China. • For the PM 2.5 , PM 10 and NO 2 models, predictors explained 87%, 71%, and 69% of variability of the pollutant distributions. • Meteorological, AOD, and GIS-derived covariates were important predictors for air pollution exposure. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) is one of the most widely used antibiotics with significant impacts on human health and thus it needs appropriate approaches for its removal. In the present study, we evaluated the performance and complete pathway of the TC electrochemical oxidation on a Ti/Ti 4 O 7 anode prepared by plasma spraying. Morphological data and composition analysis indicated a compact coating layer on the anode, which had the characteristic peaks of Ti 4 O 7 as active constituent. The TC electrochemical oxidation on the Ti/Ti 4 O 7 anode followed a pseudo-first-order kinetics, and the TC removal efficiency reached 95.8% in 40 min. The influential factors on TC decay kinetics included current density, anode-cathode distance and initial TC concentration. This anode also had high durability and the TC removal efficiency was maintained over 95% after five times reuse. For the first time, we unraveled the complete pathway of the TC electrochemical oxidation using high-performance liquid chromatograph (HPLC) and gas chromatograph (GC) coupled with mass spectrometer (MS). ·OH radicals produced from electrochemical oxidation attack the double bond, phenolic group and amine group of TC, forming a primary intermediate ( m/z  = 461), secondary intermediates ( m/z  = 432, 477 and 509) and tertiary intermediates ( m/z  = 480, 448 and 525). The latter were further oxidized to the key downstream intermediate ( m/z  = 496), followed by further downstream intermediates ( m/z  = 451, 412, 396, 367, 351, 298 and 253) and eventually short-chain carboxylic acids. We also evaluated the toxicity change during the electrochemical oxidation process with bioluminescent bacteria. The bioluminescence inhibition ratio peaked at 10 min (55.41%), likely owing to the high toxicity of intermediates with m/z  = 461, 432 and 477 as obtained from quantitative structure activity relationship (QSAR) analysis. The bioluminescence inhibition ratio eventually decreased to 16.78% in 40 min due to further transformation of TC and intermediates. By comprehensively analyzing the influential factors and complete degradation pathway of TC electrochemical oxidation on the Ti/Ti 4 O 7 anode, our research provides deeper insights into the risk assessment of intermediates and their toxicity, assigning new perspectives for practical electrochemical oxidation to effectively eliminate the amount and toxicity of TC and other antibiotics in wastewater. [ABSTRACT FROM AUTHOR]

Exposure to residential greenness might affect population health through increasing physical activity and social engagement, improving mental health, and reducing harmful environmental exposure. However, evidence on the association of greenness with risk of diabetes is still controversial. In this study, we recruited a total of 22,535 participants aged ≥18 years from Yinzhou District, Ningbo, Zhejiang Province, China to investigate the associations between residential greenness and risk of diabetes incidence. Residential greenness was estimated using Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Vegetation Continuous Field (VCF). We also calculated cumulative average NDVI, EVI and VCF values, and changes in NDVI, EVI and VCF during the follow-up period. We used Cox proportional hazards models controlling for demographic characteristics, lifestyles, individual socioeconomic status, history of diseases and particulate matter with an aerodynamic diameter ≤2.5 μm (PM 2.5) to examine hazard ratios (HRs) and 95% confidence intervals (95% CIs) and assessed physical activity, body mass index (BMI) or PM 2.5 as potential mediators. During 84,992.64 person-years of follow-up, a total of 1,154 incident cases of diabetes occurred. In multivariable models, living in the highest quartile of cumulative average NDVI, EVI and VCF within 250-m buffer was associated with 57% (HR = 0.43, 95% CI: 0.36, 0.52), 62% (HR = 0.38, 95% CI: 0.32, 0.45), and 55% (HR = 0.45, 95% CI: 0.38, 0.54) reduction in diabetes risk compared with the lowest quartile, respectively. Results remained similar for NDVI, EVI, and VCF within 500-m and 1000-m buffers. Stratified analyses showed stronger association for residential greenness and diabetes among older people. The association between greenness and diabetes did not appear to be mediated by physical activity, PM 2.5 or BMI. Our findings suggested that higher residential greenness was significantly associated with lower risk of diabetes. [Display omitted] • New evidence on the association between greenness and diabetes from China. • A prospective cohort study was conducted in 22,535 adults in China during 2015–2020. • Higher residential greenness was associated with lower risk of diabetes. • Stronger inverse association was observed among older people. [ABSTRACT FROM AUTHOR]

• Above 99.9 % of arsenic was reductively removed by the UV/sulfite process. • Valuable elemental arsenic (As(0)) with high purity (> 99.5 wt%) was recovered. • Hydrated electrons (e aq −) and H• radicals are responsible for arsenic reduction. • SO 3 •− radicals suppress the removal of arsenic by oxidizing As(0) and As(III). • Arsenic removal is effective in complex water matrices with low energy consumption. The removal of arsenic (As(V) and As(III)) from contaminated water has attracted great attention. However, the generation of arsenic-containing hazardous waste by traditional methods has become an inevitable environmental problem. Herein, a UV/sulfite advanced reduction method was proposed to remove As(V) and As(III) from aqueous solution in the form of valuable elemental arsenic (As(0)), thus avoiding the generation of arsenic-containing hazardous waste. The results showed that greater than 99.9% of As(V) and As(III) were reduced to the high purity As(0) (> 99.5 wt%) with the residual arsenic concentration below 10 μg L−1. The hydrated electrons (e aq −), H• and SO 3 •− radicals are generated by the UV/sulfite process, of which e aq − and H• serve as reductants of As(V) and As(III) while the SO 3 •− radicals inhibit arsenic reduction by oxidizing arsenic. The effective quantum efficiency (Φ) for the formation of As(0) in the As(V) and As(III) removal process is approximately 0.0078 and 0.0055 mol/Einstein, respectively. The reduction of arsenic is favorable under alkaline conditions (pH > 9.0) due to the higher photolysis efficiency of SO 3 2− than HSO 3 − (pK a = 7.2) and higher stability of e aq −/H• under alkaline conditions. The presence of dissolved oxygen (O 2), NO 2 −, NO 3 −, CO 3 2−, PO 4 3− and humic acid (HA) inhibited arsenic reduction through light blocking or e aq −/H• scavenging effects while Cl−, SO 4 2−, Ca2+ and Mg2+ had negligible effects on arsenic reduction. The proposed method can effectively remove and recover arsenic from contaminated water at a low cost, demonstrating feasibility for practical application. This study provides a novel technology for the reductive removal and recovery of arsenic from contaminated water. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] The biodegradation experiments show capsaicin was readily degradable. [•] The fish toxicity tests showed LC50 for Brachydanio rerio was 5.98mgL−1. [•] The alga growth inhibition tests show EC50 for Selenastrum capricornutum was 114mgL−1. [•] The calculated PEC is much less than the calculated PNEC for capsaicin. [•] Capsaicin used as active substance in paints poses low risk to marine environment. [Copyright &y& Elsevier]