This paper presents the results from a study on the current state of tailing dump, surrounding soil and water in the region of Tarniţa-Suceava, Romania. A number of chemical analyses and germination tests were applied in an attempt to estimate the ability of soil to maintain the plants growing, the bioavailability, and heavy metals uptake. Total heavy metals, exchangeable metals, acidity, and carbon and nitrogen content were determined. A modified sequential extraction method was used to determine geochemical phase distribution of heavy metals. The most abundant heavy metals in the studied samples were Cu, Zn, and Pb. Elevated concentrations of As were also found. The results from sequential extraction revealed that up to 51% of copper was retained by amorphous and crystalline iron oxides in soil. Higher content of lead was noticed in amorphous iron oxide fraction. The heavy metal concentration in river water during dry season varied from 0.13 mg/L (Fe) to 4.2 mg/L (Zn) and was below the maximum contamination level for drinking water. The soil toxicity and heavy metal bioavailability of tailing dump material and surrounding soils were studied by germination tests. The germinated plantlets on the studied soils were found to accumulate elevated concentrations of heavy metals thus indicating the bioavailability of soil contaminants. Soil decontamination by distilled water or magnesium nitrate solution was found to be efficient enough to improve the capability of the studied soils to support the germination process.

The European sturgeon, Acipenser sturio, is a highly endangered species that almost disappeared in the last decades. Thanks to yearly restocking of the population, this species is still found in the Gironde estuary (France), where juveniles grow during several years before leaving to the ocean. The aims of this study were to evaluate the pressure exerted on these fish by known organic and inorganic contaminants during their stay at the Gironde estuary, and to get information on the fish’s health in this context. Monthly captures over the year 2014 provided 87 fish from the cohorts 2012 and 2013 mainly, and from cohorts 2008, 2009, and 2011, all fish born in hatchery. We report the very first analyses of contaminant levels and of biological markers measured in the blood of these fish. Low inorganic contamination was found, composed of seven metals mainly Zn (< 5 μg mL⁻¹), Fe (< 1.5 μg mL⁻¹), Cu (< 0.8 μg mL⁻¹), Se (< 0.8 μg mL⁻¹), As (< 0.25 μg mL⁻¹), Co (< 0.14 μg mL⁻¹), and Mn (< 0.03 μg mL⁻¹). Concerning persistent organic contaminants, the sum of seven PCBs varied from 1 to 10 ng g⁻¹ plasma, that of eight OCPs from 0.1 to 1 ng g⁻¹, and that of eight PBDEs from 10 to 100 pg g⁻¹. Higher levels of contaminants were measured during spring as compared to summer. The sex steroid hormone plasma levels (estradiol, testosterone, and 11-ketotestosterone) were quite low, which was predictable for juveniles. The transcription of reproduction-involved genes (EstR, AR, LHR, sox9) in blood cells was demonstrated for the first time. Some of them were correlated with organic contaminant levels PCBs and OCPs. Other gene transcriptions (sodCu and bax) were correlated with PCBs and OCPs. However, the DNA damage level measured here as comet tail DNA and micronuclei ratio in red blood cells were in the very low range of the values commonly obtained in fish from pristine areas. The data presented here can serve as a reference base for future monitoring of this population of sturgeons.

Exposure to di (2-ethylhexyl) phthalate (DEHP) induces lipid metabolism disorder and high-fat diet (HD) may have joint effects with DEHP. We aim to clarify the role of JAK2/STAT5 pathway in the process and reveal the effects of HD on the toxicity of DEHP. Wistar rats (160 animals) were fed with HD or normal diet (ND) respectively and exposed to DEHP 0, 5, 50, and 500 mg/kg/day for 8 weeks. Lipid levels, as well as the morphology of liver and adipose, mRNA levels, and protein levels of JAK2, STAT5A, STAT5B, FAS, ap2, and PDK4 were detected. The results showed that DEHP exposure leads to increased weight gain. The JAK2/STAT5 pathway was activated in adipose after DEHP exposure and promoted the expression of FAS, ap2, and PDK4 in ND rats. While in the liver, JAK2 was inhibited, and lipid synthesis and accumulation were increased. However, rats exposed to DEHP in combination with HD showed a complete disorder of lipid metabolism. Therefore, we conclude that DEHP affects lipid metabolism through regulating the JAK2/STAT5 pathway and promotes adipogenesis and lipid accumulation. High-fat diet may have a joint effect with DEHP on lipid metabolism disorder.

Municipal solid waste (MSW) management and recycling has become an emerging issue in developing countries. Shanghai, the largest megacity in China, is well-known nationwide due to leading China’s MSW separation and recycling. Therefore, this paper introduces the Shanghai mode for MSW management and its current situation to enrich existing MSW management studies. Results show that the total generation volume of MSW and amount of MSW generation per capita were 9.00 million tons and 372.16 kg in 2017, increased approximately eight-fold and four-fold compared with the data in 1978, respectively. The MSW treatment rate reached 100% since 2014, with incineration rate increased to 48.56% in 2017. The cost of MSW management after implementing MSW sorting regulation is increased to 985 CNY/ton, including 390 CNY/ton of MSW sorting cost. Then three key features and innovative MSW management modes, namely, mandatory MSW sorting legislation, Green Account program, and the Combined Network program are introduced. Meanwhile, two main challenges are urgent to be responded, including inadequate collecting vehicles and limited wet waste treatment capacity. Finally, policy recommendations on strengthening MSW recycling process, constructing complete terminal treatment industry, and making systematic policies were provided to respond existing challenges.

Zero-valent iron (ZVI) has been widely applied to the remediation of uranium (U)-contaminated water. Notably, indigenous bacteria may possess potential positive or unfavorable influence on the mechanism and stability of Fe–U precipitates. However, the focus of the researches in this field has mainly been on physical and/or chemical aspects. In this study, batch experiments were conducted to explore the effects of an indigenous bacterium (Leifsonia sp.) on Fe–U precipitates and the corresponding removal efficiency by ZVI under different environmental factors. The results showed that the removal rate and capacity of U(VI) was significantly inhibited and decreased by ZVI when the pH increased to near-neutral level (pH = 6~8). However, in the ZVI + Leifsonia sp. coexistence system, the U(VI) removal efficiency were maintained at high levels (over 90%) within the experimental scope (pH = 3~8). This revealed that Leifsonia sp. had a synergistic effect on U(VI) remove by ZVI. According to scanning electron microscope and energy dispersive X-ray detector (SEM-EDX) analysis, dense scaly uranium-phosphate precipitation was observed on ZVI + Leifsonia sp. surface. The X-photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) analysis indicated that Leifsonia sp. facilitated the generation of U(VI)-phosphates precipitates. The X-ray diffraction (XRD) analyses further revealed that new substances, such as (Fe(II)Fe(III)₂(PO₄)₂(OH)₂), Fe(II)(UO₂)₂(PO₄)₂·8H₂O, Fe(II)Fe(III)₅(PO₄)₄(OH)₂·4H₂O, etc., were produced in the coexisting system of ZVI and Leifsonia sp. This study provides new insights on the feasibility and validity of site application of ZVI to U(VI)-contaminated subsurface water in situ. Graphical abstract

In order to study the effects of chemical composite additive (CCA) on the microscopic characteristics of spontaneous combustion coal, atomic force microscope and Fourier transform infrared spectroscopy technology were used to study the microstructure and active groups of spontaneous combustion coal. The roughness, three-dimensional surface morphology, microscopic pore structure, infrared spectrum, and active group content of raw coal samples and coal samples treated with water or different concentrations of CCA were analyzed. The experimental results showed that compared with the raw coal, the roughness Rq and Ra of the CCA-treated coal samples decreased with increasing CCA concentration, and the surface topography of the microscopic structure tended to be flat and smooth, and the size becomes smaller and the depth becomes shallow of pore. In the raw coal samples and coal samples treated with water and CCA, the main types of active groups remained constant. However, the contents of these groups changed, and the order of the contents of main types of active groups is water-treated > raw coal (untreated) > CCA-1% treated > CCA-5% treated > CCA-10% treated > CCA-20% treated. In addition, the mechanism of the CCA inhibition of coal spontaneous combustion was discussed and analyzed.

In recent years, China’s air pollution has caused significant concern in the academia. China is the hub of business and financial activities, with the most populous cities. It is important to determine the convergence and asymmetric persistence of air quality index (AQI hereafter) in China to achieve sustainable development goals, especially the ones related to the environment. This paper uses the Fourier quantile unit root test to check for inter-regional convergence of monthly AQI for 74 cities across China from January 2013 to July 2019. For a comparative baseline analysis, five conventional univariate and quantile unit root tests are also conducted. The empirical outcomes show that the Fourier quantile unit test exhibits a significant advantage in detecting smooth breaks and evaluating the asymmetric behavior and mean-reverting properties of AQI. Moreover, the monthly AQI in 70 out of 74 C0hinese cities are stationary processes. These findings not only focus on the appropriate use of relevant modeling techniques of smooth breaks and asymmetries in the AQI series of the 74 Chinese cities but also provide crucial environmental sustainability and economic implications for AQI regulation policies.

This work proposes a new methodology to determine the adsorption mechanism for salicylic acid and paracetamol on activated carbon based on the physicochemical characteristics of adsorbent and adsorbates. The methodology is divided into two parts: the determination of adsorption kinetics (order and mechanism) and the study of the chemical interactions (adsorbate-adsorbent and solvent-adsorbent) using calorimetry tests. Then, the results obtained in both techniques were correlated with the amount of drug adsorbed. The adsorption kinetics of salicylic acid and paracetamol on activated carbons with different oxygen contents could be described with widely kinetic models such as intraparticle, pseudo-first-order, pseudo-second-order, Avrami, and Elovich models; different information about the adsorption mechanism are offered by each of them. The results indicated that the pseudo-first-order rate constant decreases with the molecular size of analgesics and the carboxylic acid groups on the adsorbent surface; the rate constant values are between 0.12 and 2.31 h⁻¹. The adsorbed amount of analgesics and the adsorption rate are greatest on activated carbons with basic characteristics (QRAC 0.45 > 0.24 > 0.21 mmol g⁻¹ for phenol, salicylic acid, and paracetamol, respectively). The enthalpy changes follow the same trend in all activated carbons; for RAC, the results were ΔHᵢₘₘPHEN = − 33.4 J g⁻¹, ΔHᵢₘₘSA = − 35.9 J g⁻¹, and ΔHᵢₘₘPAR = − 45.4 J g⁻¹. The analgesic diffusion rate in the boundary layer increases with the formation of adsorbate-adsorbent interactions (exothermic process).

Today, society is seeking solutions to achieve sustainable development, through association between entrepreneurship, innovation and sustainable development has become a topic of great apprehension. In this perspective, this article aims to link environmental responsive entrepreneurship with sustainable development through empirical evidences from developing country. Therefore, the purpose of this study is to validate the environmental Kuznets curve hypothesis to confirm the achievement of sustainable development goals in Pakistan. We use the combined mean estimator of the autoregressive distribution lag model and GMM model to determine the long-term relationship between the variables and analyze the environmental Kuznets curve hypothesis. We found U-shaped environmental Kuznets curves in Pakistan. Further results show long-term relationship using the PMG-ARDL estimator. Our findings indicate the presence of EKC, U-shaped EKC. This means that at a certain level of economic growth, a 1% increase in per capita income can lead to reductions in environmental pollution by 2.88%, 4.54%, and 2.48%. Therefore, governments and policy makers should strengthen policies to reduce environmental pollution and, more importantly, formulate green financing policies to encourage aspiring environmental entrepreneurs to establish environmentally driven enterprises, promote the use of environmental products to reduce environmental problems, and achieve sustainable development in Pakistan.

Arsenic in fine air particulate matter (PM₂.₅) has been identified as an important factor responsible for the morbidity of lung cancer, which has increased sharply in many regions of China. Some reports in China have shown that arsenic in the air exceeds the ambient air quality standard value, while long-term airborne arsenic concentrations in central China and human exposure via inhalation of PM–bound arsenic (inhalable airborne PM) have not been well characterized. In this study, 579 outdoor air PM₂.₅ samples from Wuhan, a typical city in central China, were collected from 2015 to 2017, and arsenic was measured by inductively coupled plasma-mass spectrometry. Personal exposure to PM-bound arsenic via inhalation and urinary arsenic concentration were also measured. The concentrations of arsenic in PM₂.₅ were in the range of 0.42–61.6 ng/m³ (mean 8.48 ng/m³). The average concentration of arsenic in 2015 (10.7 ng/m³) was higher than that in 2016 (6.81 ng/m³) and 2017 (8.18 ng/m³), exceeded the standard value. The arsenic concentrations in spring and winter were higher than those in summer and autumn. No significant differences (p > 0.05) were found among different sites. The daily intake of arsenic inhalation based on PM₁₀ samples collected by personal samplers (median, 10.8 ng/m³) was estimated. Urban residents inhaled higher levels of PM-bound arsenic than rural residents. Daily intake of arsenic via inhalation accounted for a negligible part (< 1%) of the total daily intake of arsenic (calculated based on excreted urinary arsenic); however, potential associations between the adverse effects (e.g., lung adenocarcinoma) and inhaled PM-bound arsenic require more attention, particularly for those who experience in long-term exposure. This study is the first report of a 3-year temporal trend of airborne PM₂.₅-bound arsenic in central China.