ABSTRACTSoil contamination with perfluorooctanoic acid (PFOA) is a global concern. PFOA in soil can enter plants, affect plant growth and threaten food safety. Therefore, understanding the plant utilization and phytotoxicity of PFOA is conducive to assessing the environmental risk of soil contaminated with PFOA. This review analyzed recent studies about the uptake and effects of PFOA on terrestrial plants from the aspects of absorption, transport, distribution, phytotoxicity, and the underlying mechanism. Based on current research, PFOA was predominantly taken by plant roots and showed adverse effects on plants by affecting the antioxidant system and metabolic process. Research in field or higher terrestrial plants is still very scarce. Given the importance of exploring the potential remediation methods for PFOA, more research with comprehensive consideration of soil and environmental factors should be carried out to tell its specific mechanisms of plant utilization and toxicity action.

ABSTRACTNanoparticles coated with electrospun fibers cannot fully exert their inherent properties. Therefore, it is critical to develop a method to enhance the intrinsic performances of the composite fibers. In this work, UiO-66/PAN composite nanofiber membranes with good physicochemical properties were prepared by electrospinning, and a swelling method was developed to improve its performances. The adsorption performance for arsenate was improved by 19.9% or 49% after swelling by nitrobenzene or pyridine solvent, respectively. The swelling process did not change the morphologies and structures of the fibers. The pyridine solvent as the swelling agent improved the adsorption performance of the nanofiber membrane by about 45% in 1 hour. There was no detectable leached Zr in the remaining solution, indicating that the composite membrane was stable during the course. This work provides a new strategy for functional promotion of electrospun nanofiber membrane and will be helpful for environmentally friendly applications of nanocomposites in water remediation.

ABSTRACTThe physicochemical properties and heavy metals adsorption capacities of biochars derived from cattle manure (CM) and cherry wood (CW) were systematically investigated and compared. The results showed that the yields, pH and the ash content of cattle manure biochars (CMB) were higher due to high levels of mineral constituents in CM. CMB6 and CWB6 showed higher aromaticity and polarity, whereas CMB4 and CWB4 carried higher oxygen-containing functional groups. CMB6 exhibited the maximum adsorption capacities for Pb2+ (40.8 mg·g−1), Cd2+ (24.2 mg·g−1), and Ni2+ (25.1 mg·g−1), with relatively higher adsorption capacities for Pb2+ . The adsorption isotherms fitted Langmuir model, indicating that the heavy metal adsorptionoccurred via a combination of physical and chemical adsorption mechanisms. The quantitative analysis showed that the interaction with minerals was the dominant mechanism, especially accounting for about 70% in CMB6. This study provides important information for comprehensive recycling utilization of biomass for sustainable development.

ABSTRACTThe effects of rhamnolipid chelating La (III) or Nd (III) on m-dichlorobenzene removal and biofilm growth were investigated. The rhamnolipid chelating La (III) or Nd (III) significantly increased the average m-dichlorobenzene elimination capacity by 24% and 29%, respectively, on day 70–130, and the average wet weights of biomass ranged from 11 kg/m3 to 15 kg/m3 in BTFs on day 100–180 at an inlet load of at 47–98 gm3/h and an EBRT of 60s-90s. Microbial community functional genes about biofilm growth and m-dichlorobenzene removal were also increased. In addition, the rhamnolipid chelating La (III) or Nd (III) can improve the membrane permeability, extracellular polymeric substance (EPS) production, catechol 2,3 dioxygenase (C23O) enzyme, and chlorobenzene dioxygenase activity. These results demonstrate that rhamnolipid chelating La (III) or Nd (III) have the potential to improve the performance of BTFs treating hydrophobic and highly toxic VOCs.

ABSTRACTContinuous population growth associated with sanitation, food waste (FW), and domestic wastewater (DWW) is becoming critical globally. Crucial efforts and appropriate measures to utilize the FW and DWW for resources are needed. This paper reviews the conventional treatment techniques, challenges, and associated merits for treating FW and DWW. In the context of this review, DWW is often referred to as blackwater (BW)/feces. Due to the rationale for resource amplification, the review proposed that both mixtures (FW and DWW) be stored in a sub-surface storage tank for several months or years. They are further biodegraded in a bioprocess to generate energy with stabilized digestates. The effluent’s peculiar features are low organic acids with a low pH4 value, offering a stabilized and sanitized effluent. The second proposed route was to integrate anaerobic digestion, composting, and pyrolysis. Anaerobic digestion will offer bioenergy and digestates. Composting will cater to compost production and avert digestate drying and heating costs during pyrolysis. The pyrolysis of the digestates will generate biochar and bioenergy materials, while improved bioprocess performance is attained with the simultaneous biochar utilization in the bioprocess. The integrated technological routes can valorize DWW and FW for maximum resource recovery and sustainable development in a real-world context. The concept can be applied to an existing facility to create a cleaner and more efficient DWW with FW recycling. However, a comprehensive techno-economic analysis must be conducted.

ABSTRACTThis three years field study examined the influence of application rates of manure from sheep and goat (S/G) and their mixture with wood-based or farm yard manure-based biochars (FYMB) on growth performance of Foeniculum vulgare (fennel) and Cuminum cyminum (cumin). The fertilizer amendment rates were 1.66, 3.32 and 6.64 t ha−1, which were applied for three consecutive years in field. The nitrogen (N) and phosphorus (P), nitrogen use efficiency (NUE) and phosphorus use efficiency (PUE) in seeds and stover of test crops were analyzed for third year cropping only. Results demonstrated that in general, fertilizers did not influence yield of first and second year crops. The significant (P ≤ 0.05) positive influences of organic fertilizers were observed for third year crops and were of higher magnitude for C. cyminum than F. vulgare (126–306.6% increase for C. cyminum and 24.5–48.4% increase for F. vulgare than control). As compared to S/G applied at 6.64 t ha−1 rate, its co-amendment with wood-derived biochar at all application rates significantly reduced P in seeds; whereas, its co-amendment with both biochar types and at all application rates significantly reduced P in the stover of F. vulgare (Table 3; P ≤ 0.05). For the crop C. cyminum, there was no difference between treatments for the concentration of P in stover. The phosphorus use efficiency (PUE) of stover of F. vulgare was significantly improved by 80–108% and by 60–79% in response to the application of S/G and its co-amendment with FYMB respectively than control. The PUE of seeds of F. vulgare was increased by 100% than control in response to the co-amendment of manure with wood-derived biochar at high application rate (P ≤ 0.05). More profound significant improvement in PUE was observed for third year crop of C. cyminum, as most of the treatments improved PUE of seeds by171 – 561% and stover by 196–294% than control with no significant differences between fertilizer treatments. Results show no relationship between fertilizer application rates and life history trait of crops in space and time, since there was non-consistent and in general non-significant differences between fertilizer treatments for both crops.

ABSTRACTThis study compared the single and joint toxic effects of clarithromycin (CLA) and levofloxacin (LEV) on Microcystis aeruginosa. CLA was more toxic to algae than LEV, and the 96h-EC50s were 43.31 and 437.6 µg/L, respectively. The synergetic interaction of two antibiotics was detected. This synergetic action was also observed on Fv/Fm, chlorophyll a, and phycobiliprotein. The increase in reactive oxygen species (ROS) and malonaldehyde demonstrated that antibiotic exposure caused severe oxidative stress, which can destroy the membrane system, hinder photosynthesis and finally inhibit cell growth. The antioxidant enzyme activities were improved significantly, especially in the joint exposure treatment, which indicates that the antioxidant defense system can be activated to scavenge ROS. The release of microcystins (MCs) was accelerated under single or combined antibiotic exposure. The promotion of MCs discharge from cyanobacteria caused by the co-occurrence of CLA and LEV in water environment may pose a severe ecological risk to ecosystem.

ABSTRACTThis paper takes the soil around the Luqionggang landfill in Shannan city of Tibet Autonomous Region as the research object and studies the soil around the Luqionggang landfill by setting points and sampling. Then ICP-MS and AFS were used to analyze the contents of potentially toxic elements (PTEs) (Cu, Pb, Zn, Cr, Ni, Cd, As, Hg) in soil, and the health risk index method was used for risk assessment. The results showed that the primary exposure route of non-carcinogenic risk in the population was the oral route. And adults’ HI value is 0.1692, which is less than children’s HI value of 1.192, indicating that children are more affected than adults. Attention should be paid to the impact of PTEs As, Pb, and Cr in non-carcinogenic risk distribution. In the whole life cycle, the carcinogenic risk of the oral route is higher than that of the respiratory and skin contact routes.

ABSTRACTThe application of magnetic biochar (MBC) has attracted significant attention due to its recyclability and adsorption capacity for Hg from aqueous solutions. However, its applicability is still inadequate, relying on poor selectivity. Some chemical substances could improve the sorption capacity of MBC. This review offers an advanced technological route to modify-MBC composition with significant adsorption volume toward Hg. Non-polluting humic acid-sodium salts (Ha-Na) were proposed to optimize Fe3O4-modified biochar (FBC), while the pyrolyzed substrate for the initial biochar (BC) production originated from any agricultural biomass material. The non-polluting Ha-Na can improve the FBC-specific surface area, the number and structure of pores, moderate the pH and adsorb Hg(II) from aqueous solutions. Further, the interaction of three simple projected equation mechanisms is proposed for BC, FBC, and Ha-Na. BC modified with the support of Fe3O4 and optimized by Ha-Na can be applied to improve Hg(II) adsorption, while insights and future investigations are suggested.

ABSTRACTNatural and anthropogenic event information helped to simulate the physical–chemical behavior of hydrogen sulfide (H2S) in a deep oil spill and a hypothetical deep-ocean hydrothermal discharge. This research led to the development of the Lagrangian model of the discharge plumes in both cases and also analyzed the profiles of the H2S concentration at different depths taking into account its dissolution in ocean water and oceanographic conditions, such as thermohaline stratification, current fields, as well as the characteristics of the spilled hydrocarbon and the hydrothermal. The results revealed a first approximation in the identification of the dynamic behavior of the concentration profiles of H2S as a function of the oceanographic conditions. Hydrogen sulfide concentrations vary between natural and anthropogenic discharges at various depths, leading to a numerical model for applying in chemical oceanography.

ABSTRACTIn vitro toxicology research into the health effects of atmospheric particulate matter (PM) depends on the extraction of PM from filters. Previously, we proposed an efficient PM sampling and extraction method based on low-cost agar membrane and performed an exposure study with RAW264.7 macrophages. Here, we extended the application of this strategy, employing lung and hepatic cells, to validate its reliability and reproducibility. One traditional strategy using polytetrafluoroethylene (PTFE) filter was adopted for comparison. Cytotoxicity and proteomics results showed that the PM extracted by two methods induced comparable toxicity to A549 and BEAS-2B cells, while the PM extracted from the agar membranes induced higher toxicity to HepG2 and HL7702 cells than that from the PTFE filters. The differences in the investigations might be associated with the cell's sensitivity to the extracted suspended particles. This work indicated the importance of assessing PM cytotoxicity from the perspective of extraction methods and cell lines.

ABSTRACTIt is urgent to identify and screen emerging pollutants (EPs), which have caused great harm to human health and the environment. In their detection of liquid chromatography-mass spectrometry (LC-MS), the quantitative structure–retention relationship (QSRR) model is simple and efficient to predict the retention behavior of compounds. In the present work, we collected more data with the relative retention time (RRT) of 490 compounds, and filtered the molecular descriptors with lasso regression and multiple linear regression analysis. Then ten important molecular descriptors were screened and applied the QSRR models with deep neural network (DNN), multiple linear regression (MLR), and support vector machine. The DNN model had the best accuracy which the correlation coefficient R2 reached 0.913. Finally, we determined the applicability of the DNN model through a descriptor value range to assist in the identification and screening of EPs.

ABSTRACTContamination by hexavalent chromium [Cr (VI)] poses a threat to groundwater quality and its detection at point source is essential to provide early mitigating solutions. In this work, we report the fabrication of paper-based sensing system embedded with a novel nano-chromogenic complex having spherical gold nanoparticles modified with 1,5-diphenylcarbazide dye. This Au-DPC Functionalized paper strip develops pink color in <2 sec upon interaction with Cr (VI). With the developed optical fiber device a limit of detection of 0.02 ppm was achieved within a linear range of 0.01–0.4 ppm. RGB color analysis and data driven predictive modelling (KNN-model) demonstrated highest balanced accuracy score of 0.833 and cross validation accuracy of 0.714. Further, the portable optical fiber-based device offers advantages such as real-time monitoring, remote sensing capabilities, and the ability to integrate with existing optical systems for enhanced detection and analysis.

ABSTRACTHeavy metals with a high concentration value in the soil are detrimental to the soil ecosystem. In this study, 96 samples were taken from two soil sections (A-A, B-B) in the mouth of the Juanshui River to analyze heavy metal pollution. Soil pollution status and the ecological risk were investigated using Nemerow and the potential ecological risk index. The sources affecting pollution and pollution distribution characteristics were exhibited based on Inverse Distance Weighted (IDW), principal component analysis (PCA), and Statistics. Pollution in the soil of the mouth of the Juanshui River had reached a moderate level. Hg and Cd were the main potential ecological risk contributions. Coal burning and agricultural chemicals were the predominant pollution source in the study area. In order to avoid the soil of the river mouth becoming a secondary pollution source for water bodies and resulting in a vicious circle of heavy metal pollution, heavy metals in the soil of the river mouth of China should be mainly managed and controlled.

ABSTRACTHalogenated organic compounds (HOCs) are prevalent in environmental waters, but current analytical techniques are unable to identify and quantify all individual HOCs. To enhance the understanding of unregulated and unknown HOCs, total organic halogen (TOX) is proposed as a total quantity index for the overall content of HOCs in waters, and has achieved significant progresses. This paper presents a review of TOX analysis from perspectives of detection and pretreatment methods, including the measurement of halide ion (IX) or TOX content by several instruments; separation methods with enrichment based on activated carbon-adsorption, solid-phase extraction, and liquid-liquid extraction, as well as without enrichment based on the subtraction method and IX removal. The relevant fundamentals, operational processes, and key influencing factors are especially concerned. This review should be useful in understanding TOX analysis and the risk of HOCs in waters, and calls for developing more efficient TOX measurement approaches in the future.

ABSTRACTFlocculants agglomerate suspended microalgae cells, while cost and toxicity have led to the increased use of bio-flocculants. In this experiment, Chlorella pyrenoidosa was gathered by utilizing bio-flocculants from discarded clam shells. At pH 8, 0.2 mg/mL of bio-flocculant clam shell, 0.1 mg/mL of cationic inducer, and 240 rpm of mixing achieved 91.87 % flocculation efficiency and 458.1 mg of recovered biomass. Calcium ions in bio-flocculants are the main contributor to Chlorella pyrenoidosa flocculation, employing charge neutralization and sweeping as flocculation mechanisms. Zn2+ salt boosts flocculation by neutralizing the functional group's negative charge. The R2 values of 0.8969 and 0.8894 for harvesting efficiency and recovered biomass reflect the model's predictive power. XRD exhibited faint, indistinct peaks with considerable noise, indicating that the chitosan bioflocculant did not have a crystalline structure and that Chlorella had become fibrillar. Response Surface Methodology approach, which promotes flocculation, improves water reuse and microalgae harvesting.

ABSTRACTIn order to explore a fertilization scheme that can adapt to different soil fertility conditions and wheat varieties, two kinds of controlled-release ureas with different release periods (60 days (CRU-60 d) and 90 days (CRU-90 d)) blending with ordinary urea were applied in different proportions at three different sites to evaluate the impacts of controlled-release bulk blending fertilizer (CRBBF) on soil NO3–N, NH4+-N contents and dynamic change of tillers, SPAD value, grain yield and yield components. The results indicated that applying CRBBF could increase soil NO3–N, NH4+-N contents, tiller numbers, leaf areas, leaf SPAD values and grain yield. Compared with local farmers’ habitual fertilization treatment, CRBBF application presented a higher soil inorganic N content, yield with more spikes and grains per spike. This study has important guiding significance for one-time fertilization of wheat and provides an effective way to alleviate the non-point source pollution caused by excessive fertilization.

ABSTRACTCadmium is a common environmental pollutant and used for industrial purposes all over the world. Cadmium exposure causes a variety of public health issues, mainly reproductive health. The present review discusses the information related to female reproductive health, including during and after pregnancy and its outcomes. Cadmium alters steroidogenesis, delays puberty, causes pregnancy loss of reproductive hormones, disturbs the menstrual cycle, causes premature births, and reduces birth weights in females. Besides that, their offspring are affected differently by prenatal mother exposure to cadmium, with more female offspring being distressed. During lactation period, nursing babies fed with milk containing cadmium causes disparity in brain physiology, reflex changes and physical immaturity. Together, these reviews highpoint the need for more studies into the consequences of cadmium exposure on reproductive health.

ABSTRACTIn this study, activated residual Dodonaea Viscosa (ARDV) was synthesized by the simple chemical activation process as a cost-effective and sustainable adsorbent for the efficient elimination of methyl green molecule (MG) from water. The prepared ARDV was characterized by TGA, SEM, EDX, FTIR, and BET surface area analysis. The adsorption properties and mechanisms toward MG were examined using the batch method. The optimal conditions for adsorption of Pb(II) were pH= 6.6, [ARDV] =0.1 g, time=180 min, and temperature= 65°C. The adsorption isotherms and kinetics study was conducted and the resulting data fitted well with Langmuir and PSO model. The maximum sorption capacity of 99 mg/g was obtained from Langmuir isotherm for MG at 60 °C. According to thermodynamic parameters, the adsorption of MG on ARDV was endothermic and spontaneous. Hence, it could be concluded that ARDV is an inexpensive and effective bio-adsorbent for the removal of MG from polluted water.

ABSTRACTThe indoor simulation remediation of chromium-contaminated soil in semi-arid areas with chemical reduction-stabilization method was conducted to study the effects of remediation agent types and dosage, water (mL)-soil (g) ratio and remediation time on reduction and stabilization efficiency of the chromium-contaminated soil. The results showed that FeSO4 was the most effective reduction agent for reduction of Cr(VI) in soil. The optimally combined chemical reduction-stabilization remediation conditions were 2.5 times theoretical reaction dosage FeSO4 and 8% of modified corn stover biochar (KBC), 50% of water-soil ratio, and 7 days remediation time. The total Cr and Cr(VI) leaching concentrations and Cr(VI) content in soil were reduced from 65.65 mg L-1, 61.98 mg L-1 and 1000.00 mg kg-1 without treatment to 0.114 mg L-1, 0.125 mg L-1 and 18.909 mg kg-1 after treatment, respectively. They were according with comprehensive wastewater discharge standards and construction land soil contamination risk control standards, respectively.