The harm of polycyclic aromatic hydrocarbons to human health and the natural environment has become an indisputable fact. Compared with other pollutants, PAHs are more toxic at low environmental concentrations, especially in industrialized environments. This study investigated the concentration distribution of soil PAHs at a well-known industrial production site in China and applied the Monte Carlo simulation method to assess the risk of cancer caused by the excessive accidental intake of PAHs in brownfield development environments. The results showed that the PAH content of the soil at the study site exceeded the local soil quality background value to varying degrees, and the excess rate ranged from 0.72 to 22.3%. There are serious health risks of BaP at the site, which has a 95th health risk percentile value of 1.12E-04. Those for BbF, InP, and DBA range from 1.0×10⁻⁶ to 1.0×10⁻⁴, and potential health risks occur. Moreover, the exposure duration and average carcinogenic time were the most influential parameters. The study has revealed that exposure to brownfield soil contaminated with PAHs increases the health risks. This is a representative study on the occurrence and concentration of PAHs in industrial brownfields in China, which can be adopted as a basis and evidence for pollution risk assessment of brownfield development.

An important gap of knowledge exists regarding the public interest in hepato-pancreato-biliary (HPB) diseases during the coronavirus disease 2019 (COVID-19) pandemic. We aimed to understand the public interest in HPB diseases in the COVID-19 era. In this infodemiology study, we performed a comparative analysis of Google search volume of HPB terms in 2020–2021 and compared it to a similar time frame (2016–2019) in 3 periods to assess how trends in patient seeking behavior of HPB terms changed during the course of the pandemic in the USA and worldwide. Our analysis showed a substantial decrease in search volume of HPB diseases and procedure terms early in the pandemic. However, search volumes appeared to revert back to pre-pandemic years closer to the 1-year mark in USA and worldwide. Patients may have initially neglected HPB-related issues during the early phase of the COVID-19 pandemic, which could lead to worse outcomes. While HPB-related terms reverted closer to pre-pandemic levels later in the pandemic, further research is needed to assess the long-term impacts.

The focus of the present study was to explore how and to what extent ultrahigh salinity affects the adsorption of cadmium and hydrocarbon pollutants onto aluminum hydroxide adsorbents formed in an electrocoagulation process. The changes in the nature and structure of the electro-generated aluminum particles and the possible removal mechanisms due to high salt content were investigated by using FE-SEM/EDS, FTIR, BET, and XRD analyses. The pseudo-second order and Freundlich models proved to fit the data for cadmium adsorption onto the aluminum hydroxides best. It was demonstrated that the adsorption capacities were significantly affected by the high salinity. With the rise of the salinity from 2 to 170 g/L, the cadmium and COD removal yields dropped from 81 to 60% and from 90 to 72%. The increase of the oil content led to the enhanced cadmium adsorption capacity due to surface complexation and ion exchange mechanisms. It was proved that Lagergren pseudo-first-order kinetic model could justify COD abatement trends. FTIR spectra depicted that the negative impact of high salinities on the adsorption was due to causing the formation of less stable adsorbents. According to BET analysis, the occurrence of much wider pore size distribution and smaller specific surface area in high salinity case was the main reason for the decreased adsorption capacity. Based on XRD analysis, the higher crystallinity of the produced aluminum hydroxide particles and their consequential smaller surface areas resulted in the lower adsorption capacity in the hypersaline environment. It was concluded that adsorption via inner-sphere and outer-sphere complexation and sweep flocculation were the possible removal mechanisms. Total treatment cost of 8.75 and 3.49 €/m³ were estimated for low and ultrahigh salinity conditions.

Water, energy and food are three essential resources for the socio-economic system, and they are interlinked. The coordination of their internal relations is worth studying. We conduct a coordination evaluation method to assess the water-energy-food nexus (WEF Nexus) in China’s provinces. By combining the coupling model and the coupling coordination model, we measure the comprehensive evaluation index and coupling coordination degree of China’s 30 provinces from 2005 to 2017. First, the results show the provincial comprehensive evaluation index had a slow upward trend. The comprehensive evaluation index of the southern region was higher than that of the north, and the eastern was higher than the west. Second, the coordination degree of WEF Nexus in China’s 30 provinces has reached high level in the horizontal coupling stage, and the overall degree of coupling coordination was on the rise. In 2017, the WEF Nexus coupling coordination degree of most provinces reached 0.700 or more, which was intermediate-coordinated. In the six years, the 30 provinces have experienced five types of coupling coordination degree: near coordinated, barely coordinated, primary coordinated, intermediate-coordinated, and well-coordinated.

The pressure and dependence on coastal aquifers are on the rise in many parts of the globe. These lead to overexploitation, aggravated levels of groundwater pollution, and seawater intrusion. Integrated analyses can create holistic insights into the quality and the vulnerability of aquifers to seawater intrusion. In this study, Mombasa North coast’s coastal aquifer was characterized by integrating multiple approaches—GALDIT overlay index, seawater intrusion groundwater quality index GQISWI, total hardness, water quality index (WQI)—and the results were further explored and interpreted with geospatial analysis techniques. The study suggests that the predominant water type in areas under moderate or high vulnerabilities to seawater intrusion is the Na-Cl water type. However, similar Na-Cl water types can produce a range of total hardness from soft to hard. GQISWI classification can be used to narrow down the observations from Stuyfzand’s TH-based classification system. In the aquifer studied, the results of the GALDIT overlay index, a weighted aggregation of intrinsic parameters contributing to seawater intrusion, show that 29%, 59%, and 12% of the aquifer have low, moderate, and high vulnerabilities, respectively. The GQISWI analysis indicates that the groundwater is largely brackish (68%) but saline towards the southern end of the aquifer at 32%. Total hardness values indicate that 67% of the aquifer’s coverage falls under the “moderately hard” category. The geodatabase creation introduced in the study provides a template for similar studies and a baseline for future WQI and water quality monitoring. However, temporal studies on chronological timescales are recommended for sustainable management of the aquifer.

The construction of new-type urbanization with the theme of innovation, green, and smart development is becoming the endogenous driving force of China’s economic transformation and upgrading, and green technological innovation is a key factor in cracking the problems of development motivation and environmental constraints in urbanization construction. This paper investigates the impact of green technology innovation on urbanization based on a panel dataset covering 30 provinces in China from 2005 to 2019. First, we use the entropy method and the super-efficiency DEA method to measure the level of urbanization and green technology innovation, respectively. Moreover, on this basis, we use panel regression model and FGLS model to estimate the direct impact of green technological innovation on urbanization and its three dimensions-population urbanization, industrial urbanization, and ecological urbanization. Then, the mediating effect model is used to further study the indirect impact of green technological innovation on urbanization. The results indicate that green technological innovation is the most effective way to promote the development of new urbanization currently. In addition, green technology innovation can indirectly affect urbanization through the effects of foreign capital, energy consumption and information development, while the effect of industrial structure optimization effects is not significant. Finally, some policy suggestions are discussed to better promote the development of urbanization in China.

Environmental quality and economic growth are important factors that need to be balanced for sustainable development, especially in developing countries where technology is relatively backward. Many studies have shown that technology imports may be beneficial to economic growth, but once the resources and environment are taken into consideration, the role of technology imports becomes blurred. Based on provincial panel data of China from 2004 to 2019, this paper investigates the influence mechanism of domestic and foreign technology imports on the green economic efficiency (GEE) of 30 provinces in China. There are two main conclusions: First, GEE is spatially related and the impact of technology imports on GEE has a significant spillover effect. Besides, the relationship between technology imports and GEE is non-linear, both in terms of direct and indirect effects. Second, independent innovation plays an important role in the influence mechanism of technology imports on GEE. As the level of independent innovation increased, the impact of technology imports on GEE turns from negative to positive, and it is strengthened through the channel of “transfer-absorption-diffusion-re-innovation.” In this regard, some measures should be taken to enhance the role of technology imports in improving GEE.

In the present study, attapulgite (ATP)-maintained nanoscale zero-valent iron (nZVI) at different Fe/ATP mass ratios (1:3 and 1:5) was synthesized by liquid phase reduction for its use to remove chromium Cr(VI) in aqueous solution. The morphology, crystalline structure, chemical composition, and valent states of these nZVI/ATP composites were evaluated before and after the reaction. Obtained characterization data indicated an effective dispersion of nZVI on ATP surface, preventing the agglomeration of nZVI particles. Results showed that the introduction of ATP has higher Cr(VI) removal efficacy as compared to the bare nZVI or ATP. At Cr(VI) initial level of 40 mg L⁻¹, the remediation efficacy of Cr(VI) in nZVI/ATP(1:3) reached 91.63%, which was substantially higher than that of bare nZVI (48.68%) and ATP (2.52%). Co-precipitation and reduction of Cr-containing metal deposited onto nZVI/ATP were found as the major reaction mechanisms. At lower initial level of Cr(VI) (20 mg L⁻¹), the reduction was the dominant process where Fe(II) was the major form of iron in the reaction product. However, adsorption was the major mechanism at higher initial level of Cr(VI) (100 mg L⁻¹) whereas the reaction product mainly comprised the ferric form of iron (Fe(III). The main reaction product was the FeCr₂O₄ under low or high Cr(VI) concentrations which can reduce the risk of secondary pollution because of its high stability.

Over the past four decades, the Egyptian economy has suffered from both income inequality and environmental degradation. This dual problem raises the question about the nature of the relationship between inequality and the environment in a developing country like Egypt. In this regard, the study aims to examine the impact of income inequality on carbon emissions during the period 1975–2017. The analysis considers the ability of the political economy approach compared to the Keynesian trade-off approach to explain the inequality-environment relationship in Egypt. To do this, the novel dynamic autoregressive distributed lags approach is employed to capture the short-run and long-run relationships and to overcome the complications associated with the structure of the widely used autoregressive distributive lags model. The findings show that the relationship between inequality and CO₂ emissions is not a trade-off. Rather, inequality leads to environmental deterioration in the long run, but there is no significant effect in the short run. In the long run, a 1% rise in the Gini coefficient increases CO₂ emissions by 2.28%. These results support the political economy approach in explaining the inequality-environment nexus. Hence, the economic development policies adopted in Egypt during the past four decades have led to a negative impact on the environment. The study advises economic policy makers in Egypt to adopt income redistribution policies to reduce the severity of income inequality. Improving income distribution has a positive effect on the environment in Egypt.

There is profound interest in knowing the degree to which the effectiveness of China’s nature reserves, and whether leakage is common around the reserves, in the face of the most drastic conflicts between conservation and development in the world. To answer these questions, we employed the Landsat-derived Global Forest Change Dataset with 30-m resolution to examine forest change patterns during 2001 and 2017 both inside and outside of 13 typically national nature reserves in China. The average forest loss rates inside the reserves were significantly lower than those of outside the reserves (i.e., both in buffer and landscape zones), suggesting the success in protecting forest of these reserves in China. We found that the protection practice reduced approximately 10% of deforestation. Protection efficiency may be substantially overestimated (about 13–43%) if failing to control the related variables, such as altitude, climate, and human interference. The forest loss rates in the buffer zones were not significantly higher than those in the broader landscape zones, suggesting that leakage is not a frequent occurrence in the buffer zones of the reserves. However, the forest loss rates showed a slightly increasing tendency from 2001 to 2017, the loss rates increased gradually from inside to their outside buffer zones, and leakage was observed in certain zones of some years for most of the reserves. The conversions of forest to grassland and cultivated land were the primary trajectories of forest loss both inside and outside of the reserves. Though the leakage is not universal in the reserves across the country, forest loss rates are much higher in the buffer zones than those inside the reserves, resulting in increased insulation of the reserves that could undermine the provisioning of ecosystem services and the biodiversity conservation efficiency.