Bisphenol A (BPA) can potentially trigger hormonal imbalances and affect aquatic species when discharged untreated into the ecosystems. This study explored the influencing factors, mechanism, and pathways of BPA degradation process in aqueous solution applying strong ionization discharge (SID) method. The results elaborate that 99.5% degradation rate was achieved in 60 min when 15 mg L⁻¹ BPA solution was treated applying 3.74 kW of input power. Weak alkaline conditions were favorable to BPA removal in SID system. In addition, the inhibition of radical scavengers on the SID process laterally verified the presence of hydroxyl radicals (HO·) in the oxidation process besides ozone (O₃). What is more, the addition of 15 mg L⁻¹ sodium percarbonate (SPC) can improve 6.93% degradation rate of 30 mg L⁻¹ BPA based on the SID system. Furthermore, ultraviolet-visible spectroscopy (UV-vis), high-performance liquid chromatography (HPLC), total organic carbon (TOC), and chemical oxygen demand (COD) analysis were conducted to measure the capacity of SID system for BPA treatment. The molecular analysis via liquid chromatography-mass spectrometer (LC-MS) and gas chromatography-mass spectrometer (GC-MS) showed that a portion of the intermediates in BPA degradation process were characterized by 3,4-dihydroxybenzoic acid, o-xylene, p-xylene, and propane-1,2,3-triol, etc., which were ultimately mineralized into CO₂ and H₂O. Based on the above analysis, the SID oxidation mechanism and pathways were proposed.

This study investigated the feasibility and mechanism of sulfide-modified nanoscale zero-valent iron supported on biochar (S-nZVI@BC) for the removal of TCE in the scenario of groundwater remediation. The effects of some critical factors, including pyrolysis temperature of biochar, mass ratio of S-nZVI to BC, initial pH, typical groundwater compositions, co-contaminants, and particle aging time, on the TCE removal were examined. The results revealed that the different pyrolysis temperatures could change physicochemical properties of BC, which influenced the TCE adsorption and degradation by S-nZVI@BC. The mass ratio of S-nZVI to BC could determine the extent of adsorption and degradation of TCE. The total removal of TCE was not significantly influenced by the initial pH (3.0–9.0), but the degradation of TCE was enhanced at higher pH. Notably, the typical anions (SO₄²⁻, HCO₃⁻, and HPO₄²⁻), humic acid, and co-contaminants (Cr(VI) and NO₃⁻) in groundwater all slightly influenced the total removal of TCE, but markedly inhibited its degradation. Additionally, after exposure to air over different times (5 days, 10 days, 20 days, and 30 days), the reactivity of S-nZVI@BC composites was apparently decreased due to surface passivation. Nevertheless, the aged S-nZVI@BC composites still maintained relative high removal and degradation of TCE when the reaction time prolonged. Overall, the results showed that the S-nZVI@BC, combining the high adsorption capacity of BC and the high reductive capacity of S-nZVI, had a much better performance than the single S-nZVI or BC, suggesting that S-nZVI@BC is one promising material for the remediation of TCE-contaminated groundwater.

Resource endowment and economic development of different provinces in China vary greatly, resulting in large amount of CO₂ transfers. We need further exploration to help decision makers allocate emission responsibilities reasonably. We construct China’s embodied CO₂ transfer network (CTN) in 2012 from the perspective of provinces and sectors based on multi-regional input-output (MRIO) model and complex network analysis. The key CO₂ transfer nodes and paths, final demand decomposition, topological structure, clustering characteristics, and influencing factors are analyzed. The results show that the average CO₂ transfer length from one province (sector) to another is only 1.323 (1.584). The top three net CO₂ importers (45.39% of the total), located in developed eastern coastal area, mainly import CO₂ from energy-rich but underdeveloped provinces such as Heilongjiang. It presents a CO₂ transfer pattern from north to south and from west to east. CO₂ transfer in energy industry is mainly driven by urban household consumption. Non-adjacent provinces with distance greater than 750 km have no significant spillover effect and difference in technology level has the greatest impact on CTN. This work is important for differentiating the roles of provinces and sectors in CTN, guiding the allocation of carbon credits and controlling total CO₂ emissions.

Campaign-style governance is one of the political methods adopted by the Communist Party of China and the Chinese government, which is usually used to make up for shortcomings when regular governance policies fail because the defined tasks are incompatible with other policy goals, especially in the field of environmental governance. An “Environmental Protection Interview (EPI)” is one of the campaign-style environmental governance methods that target local officials. In this paper, the causal relationship between the implementation of EPI and pollutant emission reduction was confirmed using the method of Time-Varying Difference-in-difference (Time-Varying DID) to compensate for endogeneity problem and ensure that the results are still valid after several robustness checks. Our regional heterogeneous analysis shows that the policy effects of EPI decrease from east to west in China and that they have different emission reduction effects on various types of pollutants. Unfortunately, the results also suggest that policy implementation only temporarily affects pollutant emission reduction, which could be attributed to the governance approaches of campaign-style enforcement according to the impact mechanism analysis. This paper implies that the EPI should be continued to be implemented in the future with some improvements on pollutant reduction mechanisms to ensure effective adoption.

Toxicity due to heavy metals (HM), specifically mercury (Hg), arsenic (As), lead (Pb), and cadmium (Cd) remains a challenge to scientists till date. This review gives insights into natural antidotes for the management and prevention of HM toxicity. Various databases such as PubMed, Embase, and Science Direct were searched for available facts on natural antidotes and their commercial products against HM toxicity till date. Toxicity owing to such metals needs prevention rather than therapy. Natural antidotes, fruits and vegetables, rich in antioxidant are the answers to such toxicities. Synthetic chelators impart a major drawback of removing essential metals required for normal body function, along with the toxic one. Natural antioxidants are bestowed with scavenging and chelation properties and can be alternative for synthetic chelating agents. Natural compounds are abundantly available, economic, and have minimal side effects when compared with classical chelators. Prevention is better than cure and thus adding plentiful vegetables and fruits to our diet can combat HM toxicity-related illness. Graphical abstract

This research was carried out with an objective to examine the efficacy of ultrafiltered xylano-pectinolytic enzymes in pulping of sugarcane bagasse. Maximum biopulping was achieved with enzyme dose of xylanase (175 IU / g bagasse) and pectinase (75 IU / g bagasse) at treatment period of 180 min. The temperature, pH, and bagasse to liquid ratio for biopulping experiments were kept constant at 55ᵒ C, 8.5, and 1:10 (g/ml), respectively. The ultrafiltered biopulping improved chemical pulping, resulted in 25.11%, 9.17% increase in brightness, unscreened pulp production and 11.81, 59.50, and 49.14% decrease in total solids, rejections. and kappa number, respectively. The bagasse biopulping also resulted in 15% decrease of alkali load to attain similar kappa number and optical properties as obtained under 100% alkali dosage. Ultrafiltered biopulped-unbleached samples showed significant increase in breaking length (13.55%), burst index (40.21%), tear index (19.04%), double fold (42.5%), Gurley porosity (28.21%) and viscosity (13.37%) in comparison with non-enzymatically treated control pulp samples. In comparison with non biotreated-bleached pulp samples, ultrafiltered biopulped-bleached samples also resulted in higher burst index (56.80%), breaking length (17.38%), double fold (39.58%), tear index (3.38%), viscosity (30.68%), and Gurley porosity (52.50%). This environmentally sustainable ultrafiltered biopulping approach for sugarcane bagasse has the potential to decrease the demand of chemicals, ultimately pollution along with enhance the quality of paper.

This study investigates the long-term development of fog occurrences in the Metropolitan Area of São Paulo (MASP). Specifically, it analyzes the roles of meteorological and air quality parameters as potential drivers for fog formation. A dataset reaching back to the year 1933 shows that the overall trends of the annual fog occurrences (AFO) coincide with those of the annual mean temperature. Air quality data have been available since 1998, allowing us to perform a statistical analysis of the contributions of meteorology and air quality to AFO for the period from 1998 to 2018. The logistic regression model shows that the binary dependent variable (daily fog occurrence, FO) is explained by its independent predictors PM₁₀, relative humidity (rH), and daily minimum temperature (Tₘᵢₙ), in that order. FO was not found to be significantly influenced by atmospheric pressure (aP) and nitrogen oxides (NOₓ). While the influence of SO₂ was minor and associated with less confidence, it was negative. Potential causes for these surprising results are discussed. We conclude that the parameters PM₁₀, rH, and Tₘᵢₙ are significant drivers of fog formation in the MASP, whereby the total explanatory power of the drivers for the dichotomous variable FO is 16%.

Manganese (Mn) is an essential heavy metal for living organisms. However, they tend to accumulate the excess of this element causing health problems. The increase of the environmental contamination by this heavy metal is mainly due to mining practices. This work aimed to isolate yeast from mining waters to evaluate its ability of removing Mn²⁺ ions for the development of further biotechnological and bioremediation applications. The growing interest of this study is because it could be effective in the biological treatment of contaminated water, which remains a major challenge for industry and environment. Yeasts were initially isolated from mining water and grown in YPD medium containing 1 to 54 mM Mn²⁺. Subsequently, the isolates were characterized biochemically and phylogenetically. Then, we evaluate the ability of the isolates of removing Mn²⁺ ion by SEM scanning electron microscopy coupled with SEM/EDX. Our results showed yeast growth up to 32 mM. There was no pH increase along the tests, suggesting a biological Mn²⁺ removal. Taken together, the morphological changes in the colony and the darkening of the culture medium suggest the yeast’s ability of oxidizing Mn²⁺. Five isolates remove these ions considerably, identified as Rhodotorula mucilaginosa. SEM/EDX analysis shows the ability to oxidize and adsorb Mn. The data obtained in this work allows us to conclude that R. mucilaginosa has an important role in the biogeochemical cycle of manganese and present potential biotechnological applications for bioremediation of water contaminated with Mn²⁺ ions.

Air pollutants originated from natural and anthropogenic sources and able to bio-magnify and bio-accumulate in the trophic levels, thus increase toxicity in the food chain. Various air pollutants (particulate matters (PMs), volatile organic compounds (VOCs), inorganic air pollutants (IAP), persistent organic pollutants (POPs), heavy metals, and black carbon) resulted in adverse effects on environmental and human health after prolonged exposure. These airborne particles can travel in gaseous form for long distance and deteriorate the air quality of downstream areas. Air pollution abatement can be implemented by reducing emissions at source and purifying pollutants with remediation techniques. However, air pollution remained as the dominant issue to cause burden in human and ecosystem well-being. Due to drawbacks like expensive, high maintenance, and likelihood for pollutants’ reemission, existing conventional remediation technologies is insufficient for air pollutants mitigation. Phytoremediation enters the picture of air pollution control as a cost-effective, energy-saving, and environmental-friendly technology in remediating air pollutants. In phytoremediation, plant organs and associating microbes in the phyllosphere and rhizosphere interacted with each other to remediate air pollutants. Phytoremediation of air pollutants involves the rhizosphere of plants as pollutants may deposit in the soil during leaf fall and precipitation. Additionally, the phytoremediation mechanisms involve phytoextraction, phytovolatilization, phytodegradation, phytostabilization, rhizodegradation, and rhizofiltration. A brief overview of phytoremediation mechanisms for each air pollutants is presented. In short, the benefits of phytoremediation and its associated gaps in air pollution control are described.

The presence of Brazilian native bees can improve tomato production by increasing pollination effectiveness. However, the extensive use of pesticides in tomato cultures may be harmful to bees. Imidacloprid-based insecticides are used in tomato plantations because of its high efficiency against tomato pests. This study investigated the effects of oral intake of field-realistic concentrations of imidacloprid by M. quadrifasciata workers, a stingless native bee from Brazil and effective pollinators of tomato crops. The oral intake of sucrose syrup added with 10, 35, or 70 ppb of imidacloprid did not increase the mortality rate when compared with the control group. However, we observed a reduction in the workers’ motility and food consumption. We also treated M. quadrifasciata workers with sucrose syrup mixed with an imidacloprid-based insecticide (Evidence 700 WG®, Bayer), with the final concentration of 250 ppb of imidacloprid. This treatment did not cause visible alterations of the intestine absorptive cells of the bees’ midgut and did not increase DNA damage. Therefore, the observed reduction of food consumption and locomotion behavior of M. quadrifasciata workers may contribute to the global effort to understand the contribution of neonicotinoids on bees’ population decline process.