Phytoestrogens are naturally plant-derived compounds that could bind to estrogen receptors and mimic estrogenic effects. Previous studies showed a positive association between phytoestrogens and hypothyroidism; however, little is known on phytoestrogens and thyroid hormones. This study was designed to investigate the associations between urinary phytoestrogens and thyroid hormone levels. Based on the US National Health and Nutrition Examination Survey (NHANES) 2007–2010, 4103 participants were recruited in this cross-sectional study. Linear regression models and multiple linear regressions models were applied to examine the relationships between urinary phytoestrogens and thyroid hormone levels. Urinary O-desmethylangolensin (O-DMA) was found to be correlated with serum FT₄ levels in the female 20–60-year-of-age group (β=0.018, 95% CI: 0.006, 0.031). Higher enterolactone (ENT) levels were significantly positively associated with TSH levels in the 12–19-year-of-age female group (β=0.196, 95% CI: 0.081, 0.311). In the male group, enterodiol (END) was significantly positively correlated with TSH and TT₃ in the 12–19-year-of-age group, respectively (TT₃: β=3.444, 95% CI: 0.150, 6.737; TSH: β=0.104, 95% CI: 0.005, 0.203). However, equol (EQU) levels were negatively associated with TT₄ (12–19-year-of-age: β=− 0.166, 95% CI: − 0.279, − 0.034; 20–60-year-of-age: β=− 0.132, 95% CI: − 0.230, − 0.034). Our study provided epidemiological evidence that urinary phytoestrogens were powerfully associated with thyroid hormone levels. The results also supported that phytoestrogens acted as endocrine disruptors. It is imperative and important to pay attention to the intake of phytoestrogens.

This work aims to integrate several hydrogen peroxide (H₂O₂) activation mechanisms, photolysis (UVC irradiation), chemical electron transfer (TiO₂-P25 photocatalysis), and reaction with TiO₂-P25 in dark conditions, for reactive oxygen species (ROS) generation towards the removal of contaminants of emerging concern (CECs), in a single unit operated in continuous-flow mode. An H₂O₂ stock solution is fed by the lumen side of a tubular ceramic membrane, delivering the oxidant to the (i) catalyst immobilized in the membrane shell-side and (ii) annular reaction zone (ARZ, space between membrane shell-side and outer quartz tube) where CECs contaminated water flows with a helix trajectory, being activated by UV light provided by four lamps placed symmetrically around the reactor. First, the effect of several parameters in the removal of a CEC target molecule, amoxicillin (AMX), was evaluated using a synthetic solution ([AMX]ᵢₙₗₑₜ = 2.0 mg L⁻¹): (i) light source (UVA or UVC radiation), (ii) H₂O₂ dose, (iii) H₂O₂ injection method (radial permeation vs. upstream injection), and (iv) number of TiO₂-P25 layers deposited on the membrane. The UVC/H₂O₂/TiO₂ system with radial addition of H₂O₂ (20 mg L⁻¹) and 9-TiO₂-P25 layers provided the highest AMX removal efficiency (72.2 ± 0.5%) with a UV fluence of 45 mJ cm⁻² (residence time of 4.6 s), due to the synergic effect of four mechanisms: (i) AMX photolysis, (ii) H₂O₂ photocleavage, (iii) TiO₂-P25 photoactivation, and (iv) chemical reactions between H₂O₂ and TiO₂-P25. The urban wastewater matrix showed a negative effect on AMX removal (~44%) due to the presence of ROS scavengers and light-filtering species.

Extensive use of engineered nanoparticles has led to their eventual release in the environment. The present work aims to study the removal of Polyvinylpyrrolidone-coated silver nanoparticles (PVP-Ag-NPs) using Aspergillus niger and depict the role of exopolysaccharides in the removal process. Our results show that the majority of PVP-Ag-NPs were attached to fungal pellets. About 74% and 88% of the PVP-Ag-NPs were removed when incubated with A. niger pellets and exopolysaccharide-induced A. niger pellets, respectively. Ionized Ag decreased by 553 and 1290-fold under the same conditions as compared to stock PVP-Ag-NP. PVP-Ag-PVP resulted in an increase in reactive oxygen species (ROS) in 24 h. Results show an increase in PVP-Ag-NPs size from 28.4 to 115.9 nm for A. niger pellets and 160.3 nm after removal by stress-induced A. niger pellets and further increased to 650.1 nm for in vitro EPS removal. The obtained findings show that EPS can be used for nanoparticle removal, by increasing the net size of nanoparticles in aqueous media. This will, in turn, facilitate its removal through conventional filtration techniques commonly used at wastewater treatment plants.

This study was carried out to determine the effect of cow manure amendment and the method of planting on the growth, survival, and heavy metal accumulation of Colophospermum mopane seedling grown on Bamangwato Concessions Limited (BCL) mine tailings. Different planting strategies were employed where the mopane seedlings were planted with bare roots (devoid of potting soil) and without cow manure (T1, − CM − Soil); with the potting soil adhering to the roots but without cow manure (T2, − CM + Soil); with bare roots in the presence of cow manure (T3, + CM − Soil); and with potting soil intact together with cow manure (T4, + CM + Soil). Cow manure increased the pH of the mine tailings enhancing the survival and growth of the mopane seedlings. Seedlings grown under T1 conditions had a higher concentration of the heavy metals As, Cr, Cu, Mn, Ni, Pb, Zn, Sb, and Sr in their shoots compared to those grown under a T4 environment consisting of potting soil with cow manure. Cow manure decreased the availability of these heavy metals in mine tailings through the humic substance which adsorbed the heavy metal while the soil adhering to the roots diluted the concentration of heavy metals in the rhizosphere thus reducing the uptake and toxicity. Overall, the establishment of mopane seedlings in mine tailings could be enhanced by cow manure amendments and with soil adhering to its roots during transplanting.

Excessive cobalt exposure has been shown to induce various adverse health effects in animal and human toxicity studies. However, the relationships between cobalt exposure and obesity, insulin resistance, and metabolic-related disorders are rarely studied in epidemiological studies. This study aimed to explore the dose–response relationships between urinary cobalt concentrations and obesity, insulin resistance, and metabolic-related disorders. Adult participants (≥20 years) from the 2005 to 2018 National Health and Nutrition Examination Survey were included. Restricted cubic splines and the log-binomial regression were adopted. Multivariate adjusted prevalence ratios (95% confidence intervals) comparing extreme quartiles of urinary cobalt concentrations were 1.43 (1.29–1.57) for obesity, 1.43 (1.10–1.86) for insulin resistance, 1.21 (1.09–1.34) for metabolic syndrome, 1.16 (1.10–1.23) for elevated waist circumference, 1.20 (1.09–1.33) for elevated triglycerides, 1.14 (1.01–1.29) for reduced high-density lipoprotein cholesterol (HDL-C), 1.06 (0.98–1.15) for elevated blood pressure, and 0.91 (0.79–1.06) for elevated fasting glucose, respectively. Results from the restricted cubic splines showed that an initial steep increase in risk was followed by a weaker increase in risk or a platform beyond 1.0 µg/L for obesity (prevalence ratio (95% confidence interval): 1.41 (1.29–1.55)), insulin resistance (1.33 (1.07–1.65)), metabolic syndrome (1.18 (1.11–1.31)), elevated waist circumference (1.18 (1.11–1.25)), elevated triglycerides (1.21 (1.11–1.33)), and reduced HDL-C (1.15 (1.01–1.30)), respectively. In conclusion, the prevalence of obesity, insulin resistance, metabolic syndrome, elevated waist circumference, elevated triglycerides, and reduced HDL-C progressively increased with increasing urinary cobalt concentrations. The above associations are non-linear and there is not a “safe threshold” below which there are no toxic effects of cobalt.

The Yellow River basin (YRB) is China’s most critical energy consumption and coal production area. The improvement of carbon emission reduction efficiency in this area is the key for the Chinese government to achieve the 2030 carbon peak and 2060 carbon neutral (“30.60”). Given this, this study first calculates the carbon emission efficiency of YRB from 2005 to 2019 based on the slack-based measured directional distance function (SBM-DDF) model and combined with Malmquist–Luenberger (ML) index and decomposes the carbon emission efficiency of each province. Then, a panel Tobit model with random effect is constructed to measure the influencing factors and their influence degree of carbon emission efficiency of YRB. Finally, the main influencing factors are selected, and policy suggestions on how to improve the carbon emission efficiency of each province are put forward with the help of the coupling coordination degree (CCD) model. The results show that first, the carbon emission efficiency of each province is significantly different, but it shows a fluctuating upward trend on the whole. Second, the reasons for the rise or decline of the ML index in different provinces are different. Therefore, the development strategies of different provinces should be formulated from the perspective of accelerating technological progress and improving technical efficiency. Finally, the calculation results of influencing factors and coupling coordination degrees show that provinces with high coupling coordination degrees should focus on developing per capita power consumption and controlling per capita power consumption to consolidate the actual urbanization process and industrial structure adjustment. Provinces with low coupling coordination degrees should focus on maintaining the urbanization process and increasing the development of the tertiary industry. Therefore, to fundamentally reduce carbon emissions in YRB areas, we need to consider implementing differentiated emission reduction schemes based on national strategic objectives and in combination with the development characteristics of various provinces.

The sludge resource utilization and the high value-added development are environmentally friendly means for sludge treatment. With its rich organic substances and metals content, sludge can replace activated carbon and become a widely used carbon-based material, such as sludge-based activated carbon (SBAC). Meanwhile, as a heterogeneous catalyst, sludge-based catalyst (SBC) can solve the requirements of traditional Fenton catalysts for pH, metal ion leaching, and catalyst recycling. In this paper, combining the properties of SBAC/SBCs, the characteristics of the three methods of activation, support, and hydrothermal preparation of SBAC/SBCs are reviewed. In general, it is necessary to select an appropriate preparation method based on pollutants and environmental treatment goals. Furthermore, compared with other catalysts, SBC heterogeneous oxidation has obvious advantages in refractory organic pollutants. And the reaction mechanism usually involves SO₄·⁻, ·OH, O₂·⁻, and ¹O₂ processes. Finally, some possible directions for future research involving environmentally friendly SBAC/SBCs are proposed.

Economies that depend on natural resources can experience a resource drag effect when economic growth is limited by constraints on the availability of those resources. Therefore, this study uses panel data and the improved Solow growth model to explore the resource drag effect on China’s regional economic growth from 1987 to 2017 and makes innovative contributions to address these four gaps in the previous literature: the resources gap, the consistent measurement gap, the regional gap, and the temporal gap. The empirical results indicate that the resource drag effect reduced China’s overall annual economic growth by 0.58% during the study period, with reductions of 1.07%, 0.29%, 0.79%, and 0.46% in the Eastern, Western, Central, and Northeastern regions, respectively. In the meantime, the resources drag effect changed in individual regions and across regions. The results on energy drag are most notable. Policies such as “West-to-East Electricity Transmission” and “West-to-East Gas Transmission” promoted economic growth of the Eastern and Western Region, facilitating continued growth in both regions and attracted the return of labor to the Western region. The results indicate that the policies such as west-to-east energy transfer for helping to even out the economic growth conditions in different regions. Labor force mobility has also been important to alleviate resource dependence of agricultural production in Central regain, while other regions have managed to continually grow through improvements in inefficiency. Also, growth in some regions/provinces continues to depend upon increases in water, land, and energy availability and export. This will become increasingly problematic as the social prices of these inputs rise to account for environmental damage. Therefore, the government should adjust the industrial structure of each region to optimize use of resource endowments, alleviate dependence on natural resources, and achieve sustainable economic development.

This research paper deals with the experimental investigation of solar energy–based water purifier (SEBWP) of single-slope type by incorporating N similar evacuated tubular collectors (ETCs) having series connection. Experimental investigation has been done for a year from August 2018 to July 2019. MATLAB has been used for evaluating performance parameters of the system followed by the validation of these results with their experimental values. A fair agreement has been found between theoretical and experimental values. Values of correlation coefficients for condensing glass temperature, water temperature, and water yield have been found to be 0.9932, 0.9928, and 0.9951 respectively. Further, energy metrics, productivity, cost of producing 1 kg of fresh water, and exergoeconomic and enviroeconomic parameters have been evaluated. Values of energy payback time, per kilogram cost of producing fresh water and exergy loss per unit Rs. have been evaluated to be 1.72 years, Rs. 0.95/kg, and 0.128 kWh/Rs. respectively.

Because of global environmental problems, low-carbon agriculture has gained increasing importance both in developed and developing countries. Hence, there is a need to find ways to develop more efficient agricultural systems. The purpose of this article is to identify the drivers of low-carbon agriculture on farms in the Wielkopolska region (in Poland). We aimed to take an original approach to investigate low-carbon agriculture with a unique set of different economic and environmental variables and contribute to the literature, which is not very extensive in terms of microeconomic research, including research on farmers in the Wielkopolska region. Therefore, we employed a multiple-factor measurement model for structural equation modeling (SEM) of data collected individually from 120 farms in 2020. As a result, we formulated the following conclusions: the increasing productivity of factors (land, labor, and capital) have a positive effect on low-carbon farming, just as increasing fertilizer and energy efficiency. Moreover, thermal insulation is also important for low-carbon agriculture, with efficiency of fertilizer use being the most important factor. We believe that the issues of farm use of fertilizers and thermal insulation of buildings should be more broadly included in energy policy, both at the national and the European Union (EU) levels. Some of these factors however are already present in the common agricultural policy (CAP) for 2021–2027.