In this work, a new type of advanced 3D mesoporous carbon nanocomposites derived from Zn dust/PET bottle mixed waste with a high surface area is created. Interestingly, simultaneous transformation of Zn metal into ZnO nanoparticles and PET bottle waste to porous carbon materials occurred upon thermal treatment at 700 °C. The effect of the amount of Zn metal on the prepared materials has been studied. The carbon material-based waste presented very large surface area (up to 684.5 m²/g) with pore size distribution (18.47–16.88 nm). The SEM and TEM analysis revealed that the produced carbon materials have 3D porous dense layers with a gradient pore structure. The created waste-based nanocomposite exhibited an enhanced photocatalytic performance for the degradation of organic dyes (methylene blue and malachite green). It is believed that the presented work not only provides a sustainable approach to the creation of new nanocomposites of ZnO-mesoporous carbon materials for the application in photocatalysis but also introduces a new way of upcycling of mixed waste materials.

Currently, several news channels and research publications have highlighted the dilemma of arsenic (As)-contaminated groundwater in Pakistan. However, there is lack of data regarding groundwater As content of various areas in Pakistan. The present study evaluated As contamination and associated health risks in previously unexplored groundwater of Hasilpur-Pakistan. Total of 61 groundwater samples were collected from different areas (rural and urban), sources (electric pump, hand pump, and tubewell) and depths (35–430 ft or 11–131 m). The water samples were analyzed for As level and other parameters such as pH, electrical conductivity, total dissolved solids, cations, and anions. It was found that 41% (25 out of 61) water samples contained As (≥ 5 μg/L). Out of 25 As-contaminated water samples, 13 water samples exceeded the permissible level of WHO (10 μg/L). High As contents have been found in tubewell samples and at high sampling depths (> 300 ft). The major As-contaminated groundwater in Hasilpur is found in urban areas. Furthermore, health risk and cancer risk due to As contamination were also assessed with respect to average daily dose (ADD), hazard quotient (HQ), and carcinogenic risk (CR). The values of HQ and CR of As in Hasilpur were up to 58 and 0.00231, respectively. Multivariate analysis revealed a positive correlation between groundwater As contents, pH, and depth in Hasilpur. The current study proposed the proper monitoring and management of well water in Hasilpur to minimize the As-associated health hazards.

A pot experiment and a leaching experiment were conducted to investigate the effects of earthworms and pig manure on heavy metals (Cd, Pb, and Zn) immobility, in vitro bioaccessibility and leachability under simulated acid rain (SAR). Results showed manure significantly increased soil organic carbon (SOC), dissolved organic carbon (DOC), available phosphorus (AP), total N, total P and pH, and decreased CaCl₂-extractable metals and total heavy metals in water and SAR leachate. The addition of earthworms significantly increased AP (from 0.38 to 1.7 mg kg⁻¹), and a downward trend in CaCl₂-extractable and total leaching loss of heavy metals were observed. The combined earthworm and manure treatment decreased CaCl₂-extractable Zn, Cd, and Pb. For Na₄P₂O₇-extractable metals, Cd and Pb were decreased with increasing manure application rate. Application of earthworm alone did not contribute to the remediation of heavy metal polluted soils. Considering the effects on heavy metal immobilization and cost, the application of 6% manure was an alternative approach for treating contaminated soils. These findings provide valuable information for risk management during immobilization of heavy metals in contaminated soils.

To investigate the effects of government environmental regulation and industrial structure changes on carbon dioxide emissions, this research analyzes annual data over the period 2003–2015 covering 30 provinces in China (except for Tibet) with the panel smooth transition regression (PSTR) model. The empirical results show obvious non-linear effects of environmental regulation and industrial structure on carbon dioxide emission. Taking the effects of both linearity and non-linearity into consideration, environmental regulation will reduce carbon emissions with the change of industrial structure rationalization (SR). When the level of industrial structure optimization (SH) is low, environmental regulation promotes carbon dioxide emissions. When the level of industrial structure optimization (SH) is high, environmental regulation plays a significant inhibitive role on carbon dioxide emissions. The Kuznets relationship between GDP per capita (PGDP) and carbon dioxide emissions is influenced by local industrial structure rationalization and industrial structure optimization. Therefore, environmental regulation policies suitable for local conditions should be made based on the transition of the local industrial structure.

To optimize the simultaneous removal of NOₓ and Hg⁰, a series of CuₐCebZrcO₃/γ-Al₂O₃ catalysts prepared by the impregnation method were explored and their physical and chemical properties were analyzed by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), NH₃-temperature-programmed desorption (NH₃-TPD), H₂-temperature-programmed reduction (H₂-TPR), in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFT), and Fourier transform infrared spectroscopy (FT-IR). The results showed that 15% Cu₁.₄Ce₀.₅₅Zr₀.₂₅O₃/γ-Al₂O₃ resulted in the highest conversion efficiency for the simultaneous removal of NOₓ (93%) and Hg⁰ (85%) at low temperatures (200 to 300 °C). Meanwhile, 15% Cu₁.₄Ce₀.₅₅Zr₀.₂₅O₃/γ-Al₂O₃ showed good stability and resistance to SO₂ and H₂O, which is due to its low crystallinity, good textural performance, and strong redox ability. According to the TPD, TPR, and XPS results, the strong acidic character of 15% Cu₁.₄Ce₀.₅₅Zr₀.₂₅O₃/γ-Al₂O₃ promoted the removal of NOₓ and Hg⁰. The synergistic effect between CuO and CeO₂ in 15% Cu₁.₄Ce₀.₅₅Zr₀.₂₅O₃/γ-Al₂O₃ can increase the mobility of chemically adsorbed oxygen and activates lattice oxygen, leading to an excellent performance. The DRIFT results showed that NH₃, NH₄⁺, nitrate, and nitrite participated in the selective catalytic reduction (SCR) reaction. On the basis of our experimental results, Hg⁰ and NOₓ removal mechanisms were proposed as Hg (ad) + O* → HgO (ad) and 2NH₃/NH₄⁺ (ad) + NO₂/NO₃⁻ (ad) + NO→2N₂ + 3H₂O/2H⁺, respectively.

This paper studies the impact of six main air pollutants on three key dimensions of subjective well-being (SWB) – life satisfaction, hedonic happiness and mental health. We match a nationally representative survey in China with local air quality and rich weather conditions according to the exact date and county of each interview. By making use of variations in exposures to air pollution across similar respondents living in the same county, we find that PM2.5 reduces hedonic happiness and increases the rate of depressive symptoms, but does not affect life satisfaction. Our results show that the benefits of reducing air pollution would be higher if the hidden costs of air pollution on SWB in China are taken into account.

Anthropogenic marine debris is one of the major worldwide threats to marine ecosystems. The EU Marine Strategy Framework Directive (MSFD) has established a protocol for data collection on marine debris from the gut contents of the loggerhead sea turtle (Caretta caretta), and for determining assessment values of plastics for Good Environmental Status (GES). GES values are calculated as percent turtles having more than average plastic weight per turtle. In the present study, we quantify marine debris ingestion in 155 loggerhead sea turtles collected in the period 1995e2016 in waters of western Mediterranean (North-east Spain). The study aims (1) to update and standardize debris ingestion data available from this area, (2) to analyse this issue over two decades using Zero-altered (hurdle) models and (3) to provide new data to compare the only GES value available (off Italian waters). The composition of marine debris (occurrence and amounts of different categories) was similar to that found in other studies for the western Mediterranean and their amounts seem not to be an important threat to turtle survival in the region. Model results suggest that, in the study area, (a) period of stranding or capture, (b) turtle size and (c) latitude are significant predictors of anthropogenic debris ingestion (occurrence and amount) in turtles. The GES value for late juvenile turtles (CCL>40 cm) has decreased in the last ten years in the study area, and this is very similar to that obtained in Italian waters. We also provide a GES value for early juvenile turtles (CCL 40 cm) for the first time. Recommendations arising from this study include ensuring use of (1) the standardized protocol proposed by the MSFD for assessing marine debris ingestion by loggerhead sea turtles and (2) the ecology of the turtles (neritic vs oceanic), rather than their size, to obtain GES values.