The three-year Black Carbon (BC) aerosol measurements made during 2020, 2021, and 2022 over a rural location, namely, Panchgaon, surrounded by Aravali hillocks (elevation of about 400-600 m) have been analyzed with an aim to determine their optical and radiative characteristics, seasonal and long-term variations in mass concentration. The affinity between these parameters and associated pollutants and planetary boundary layer height (PBLH), affected by the orography, to delineate their role in mass concentration changes with time have been investigated. The coincident OPAC (Optical Properties of Aerosols and Clouds) Model-derived aerosol optical depth (AOD), and single scattering albedo (SSA) have been compared with the observed BC mass concentration, and also with synchronous satellite measurements. The year-to-year variability analysis of the data reveals that the rate of increase of BC concentration is high. The variability was low due to the reasons explained. It implies that the year-to-year variability in BC concentration at the study site depends on the source strength modulated by the valley-driven meteorology. Added, the percentage departures of BC concentration show positive values (higher concentration) during morning and evening hours, which could be due to more anthropogenic activities while it shows negative values during afternoon hours and lower boundary layer heights. The force exerted by the radiation due to BC aerosols at the bottom of the atmosphere (BOA), and in the atmosphere (ATM) are almost equal in magnitude and negative, while that at the top-of-the-atmosphere (TOA) is smaller and positive, indicating that BC aerosols in the study region cools the atmosphere at the BOA and warms the ATM and TOA, which indirectly reveals the dominant role of long-range transport phenomenon at higher levels as compared to the surface level.

Leachate leakage poses a serious environmental risk to the safety of surrounding soils and groundwater. A much faster approach to reflect landfill leakage is the premise to mitigate the ecological risk of landfills. In this study, two landfills (BJ and WZ) were selected to investigate the leaching characteristics of various pollutants along the vadose soil depths. The physiochemical properties of underlying soils including NO3--N, NO2--N, NH4+-N, OM, TN, EC and Cl- exhibited a typical leaching dynamic along the depths. Among them, TN, NH4+-N, OM, NO3--N, and EC might be used as characteristic pollutants to evaluate the leachate leakage issues in landfilled sites. The genera Thiopseudomonas, Acinetobacter, Pseudomonas, and Hydrogenispora dominated in underlying soils. Compared to BJ samples, a more diverse and active microbiome capable of carbon and nitrogen cycles was observed in WZ samples, which was mainly ascribed to nutrients and elements contained in different types of soils. Among the environmental factors, nitrogenous compounds, SO42-, pH and EC had significant effects on the microbial community structures in the underlying soils. The relative abundances of Hydrogenispora and Caldicoprobacter might be used as characteristic microorganisms to evaluate the leachate leakage issues in landfilled sites. These results provided a deep insight into effects of leachate leakage in underlying soils, especially the pollutants vertical distribution and the corresponding microbial community structures.

The resource disposal of electrolytic manganese residue can effectively solve the problem of environmental pollution caused by it, among which the problem of heavy metal pollution is the most prominent. In this study, a new type of eco-friendly brick mixed with electrolytic manganese residue was designed. The influence of the content of electrolytic manganese residue on its macroscopic properties, microscopic properties, and leaching characteristics was analyzed by test methods such as compressive strength test, radioactivity test, XRF, XRD, FTIR, and ICP test of bricks. The results showed that the manganese content in the EMR leachate was 8120 mg/L, which exceeded the Chinese standard. The leaching experiment of ordinary aqueous solution of sintered bricks mixed with 20% EMR showed that the content of heavy metals was far lower than the Chinese national standard. There was no non-carcinogenic risk of heavy metals in the strong acid leaching solution of sintered bricks mixed with 20% EMR. Only the carcinogenic risk values of Cr for adults and children were 4.21 × 10-4 and 9.82 × 10-4 respectively, both exceeding the USEPA limit, but the application scene of sintered bricks was difficult to achieve strong acidity, so it was judged that it had no carcinogenic risk to the human body. Characteristic heavy metals such as Mn, Cr, and As existed stably in sintered bricks through substitution and encapsulation. In addition, the compressive strength and radioactivity of EMR sintered bricks met the requirements of the Chinese national standard \"Fired Ordinary Bricks.\" This product can be used as national standard MU20 grade brick. This study provided an efficient method for the safe and environmentally friendly disposal of EMR in a sustainable control system.

The waste product phosphogypsum (PG) is produced in phosphoric acid production processes. Its storage requires large amounts of land resources and poses serious environmental risks. In this work, detailed experimental research was carried out to investigate the potential reuse of PG after calcination modification as a novel building material for cast-in-place concrete products. The calcination modification mechanism was studied, and the environmental risk assessment of modified PG was presented. The results showed that the calcination modification includes crystal phase transformation, removal of impurities, and modifying the pH value. The calcination was carried out at 280 °C for 5 h, where the resulting product was a pH value of 7.1, and the soluble fluorine and phosphorus removal rates reached up to 69.2% and 71.2%, respectively. These removal rates met the requirements of the China national standard Phosphogypsum (GB/T 23456-2018). To ensure the environmental safety, ecological risk assessment methods for determining the leaching toxicity of the modified PG were employed. The toxicity of Ba and P elements in the modified PG products was assessed, as well as the leaching toxicity concentrations of all particular heavy metals, which were found well below the limits set by the national standards. All the results presented strongly suggest that the 280 °C modified PG presented here has excellent application potential as a raw component in building materials.

Pharmaceuticals and personal care products (PPCPs) in the sea area surrounding a densely populated tourist city in southeastern China were investigated. In total, 32 PPCP pollutants classified into 23 categories were detected. Different spatial distribution patterns of PPCPs indicated possible contamination from runoff and multiple local sources. The labile-to-conservative ratios of PPCPs showed the influence of untreated domestic sewage. In addition, increased concentrations of ciprofloxacin, enrofloxacin, and erythromycin around aquaculture farms imply that aquaculture cannot be neglected as a source. The concentrations of oxytetracycline, ranitidine, ciprofloxacin, miconazole, and sulfamethizole were higher in the wet season than those in the dry season, and the difference in pharmaceutical consumption was suspected to be the main driving factor of this seasonal variation. The risk quotients calculated with the maximum concentrations of miconazole, triclosan, dehydronifedipine, and triclocarban exceeded 0.1, indicating potential moderate or high risks. Antibacterial agents in daily chemicals and azole broad-spectrum antifungals were associated with the highest risks in this study; this might be another significant pollution characteristic in the sea area around this subtropical tourist city.

From March 2018 to February 2019, quantitative detection was made of 102 kinds of atmospheric volatile organic compounds (VOCs) using online gas chromatography in Ezhou City. We compared and analyzed the composition, seasonal variation, and diurnal variation of VOCs. Using maximum incremental reactivity (MIR), we estimated the ozone generation potential (OFP) of VOCs. The results show that the annual average volume fraction of atmospheric VOCs in Ezhou is (30.78±15.89)×10-9, and is overall higher in winter than summer, represented by alkane > oxygen > halogenated hydrocarbon > olefin > aromatic hydrocarbon > alkyne. The night volume fraction is higher than in the daytime, and overall the distribution is \"double peak\". The aromatic hydrocarbons, halogenated hydrocarbons, and OVOCs appear as a \"third peak\" at 00:00-02:00. Aromatic hydrocarbons and olefins contribute more to the OFP potential of VOCs, with contribution rates of 35.45% and 29.5%, respectively. The highest contribution rate to OFP is ethylene, reaching 24.217%. Analysis of VOC characteristic species found that vehicle exhaust fumes and solvent volatilization are the main sources of VOCs in Ezhou. Of these, motor vehicle emissions are the most important source. Controlling Ezhou\'s motor vehicle emissions helps to reduce the composition of atmospheric VOCs, thereby reducing ozone production.

Owing to the production and use of chemicals in chemical industry parks (CIPs), these areas are considered to be highly polluted. However, the type of pollutants presents in the wastewater from CIPs and the risk posed to the environment due to the release of these pollutants remains unclear. In this study, suspect screening was combined with traceability analysis to determine the type of pollutants present in wastewaters at 9 chemical enterprises and wastewater treatment plants (WWTPs) in the CIPs. Additionally, the distribution of nine pollutants from the WWTPs\' effluent stage and the risk they posed to the surrounding river was examined through target analysis. Upon conducting suspect analysis, the presence of 65 and 64 chemicals in the 9 chemical enterprises\' wastewaters and WWTPs, respectively, was tentatively identified. Traceability analysis of the compounds screened in the effluent from the WWTPs determined that 41 substances were identified as characteristic pollutants of the chemical enterprises, indicating that the suspect screening strategy enabled relatively more efficient identification of the characteristic pollutants compared to traditional quantitative analysis. Targeting analysis combined with ecological risk assessment showed that metolachlor, carbendazim, atrazine, diuron, and chlorpyrifos posed relatively higher risks to aquatic organisms in the surrounding river. Therefore, the refined management of the wastewater treatment plant in the CIPs is necessary.