Sep 2024, Volume 18 Issue 9
    

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  • Municipal water and wastewater treatment is essential to control pollution and protect water ecology. More importantly, it has become a key link in promoting sustainable development for society, the economy, and the environment. Urban water treatment facilities have greatly improved the quality of life for city dwellers. These advanced systems ensure the purification and supply of clean water, making it safe for drinking, cooking, and daily use. As a result, the incidence [Detail] ...

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  • ERRATUM
    Zhicheng Liao, Bei Li, Juhong Zhan, Huan He, Xiaoxia Yang, Dongxu Zhou, Guoxi Yu, Chaochao Lai, Bin Huang, Xuejun Pan
  • RESEARCH ARTICLE
    Jun Wang, Mingtao Huang, Bolin Li, Hassan Ibrahim Mohamed, Huanjie Song, Gezi Li, Ying Yu, Han Zhang, Weimin Xie

    ● Spatiotemporal distribution of conventional and emerging pollutants was analyzed.

    ● Removal of pollutants by different precipitation and filtration processes was assessed.

    ● Effect of ozone-activated carbon process on pollutant removal efficiency was determined.

    Emerging pollutants, such as antibiotics and antibiotic-resistance genes, are becoming increasingly important sources of safety and health concerns. Drinking water safety, which is closely related to human health, should receive more attention than natural water body safety. However, minimal research has been performed on the efficacy of existing treatment processes in water treatment plants for the removal of antibiotics and antibiotic resistance genes. To address this research gap, this study detected and analyzed six main antibiotics and nine antibiotic resistance genes in the treatment processes of two drinking water plants in Wuhan. Samples were collected over three months and then detected and analyzed using ultra-high-performance liquid chromatography-tandem mass spectrometry and fluorescence quantitation. The total concentrations of antibiotics and antibiotic resistance genes in the influent water of the two water plants were characterized as December > March > June. The precipitation and filtration processes of the Zou Maling Water Plant and Yu Shidun Water Plant successfully removed the antibiotics. The ozone-activated carbon process increased the removal rate of most antibiotics to 100%. However, a large amount of antibiotic resistance gene residues remained in the effluents of the two water plants. The experiments demonstrated that the existing ozone-activated carbon processes could not effectively remove antibiotic resistance genes. This study provides a reference for the optimization of drinking water treatment processes for antibiotics and antibiotic resistance gene removal.

  • RESEARCH ARTICLE
    Xiaodong Wei, Jianlin Hu, Chao Liu, Xiaodong Xie, Junjie Yin, Song Guo, Min Hu, Jianfei Peng, Huijun Wang

    ● CS structure overestimates ρ eff by nearly six times at externally mixed states.

    ● FA method reproduces the evolution of BCc morphology.

    ● MSTM can reproduce a more realistic evolution of optical properties.

    ● A two-stage calibration of E abs as the function of coating fractions is developed.

    Measurements studies have shown that the absorption of radiation by black carbon (BC) increases as the particles age. However, there are significant discrepancies between the measured and modeled absorption enhancement (Eabs), largely due to the simplifications used in modeling the mixing states and shape diversities. We took advantage of chamber experiments on BC aging and developed an efficient method to resolve the particle shape based on the relationship between the coating fraction (∆Dve/Dve,0) and fractal dimension (Df), which can also reflect the variations of Df during the whole BC aging process. BC with externally and partly mixed states (0 ≤ ∆Dve/Dve,0 ≤ 0.5) can be considered to be uniformly distributed with the Df values of 1.8–2.1, whereas the Df values are constrained in the range 2.2–2.8 for fully mixed states (∆Dve/Dve,0 > 0.5). The morphological parameters (i.e., the effective density and the dynamic shape factor) were compared with the measured values to verify the simulated morphology. The simulated mean deviations of morphological parameters were smaller than 8% for the method resolving the particle shape. By applying a realistic shape and refractive index, the mass absorption cross for fully mixed states can be improved by 11% compared with a simplified core–shell model. Based on our understanding of the influence of Df and ∆Dve/Dve,0 on Eabs, we propose a two-stage calibration equation to correct the Eabs values estimated by the core–shell model, which reduces the simulation error in the Mie calculation by 6%–14%.

  • RESEARCH ARTICLE
    Xiaobin Liao, Xinyue Liu, Yueyun He, Xueping Tang, Ruanjunjie Xia, Yongjun Huang, Wenhua Li, Jing Zou, Zhenming Zhou, Mazhan Zhuang

    ● Combined proposals achieved higher disinfection efficiencies than singular ones.

    ● Cl2 produced the most DBPs, combined proposals can reduce their formation.

    ● Cl2 could damage bacterial cell membrane and caused the leakage of IOM.

    ● The toxicity by zebrafish embryo followed: Cl2≈O3/Cl2 > O3 > O3/UV/Cl2 > UV > UV/Cl2.

    ● UV/Cl2 was suggested to deal with COVID-19 epidemic for sewage treatment plants.

    During the COVID-19 pandemic, most sewage treatment plants increased disinfectant dosages to inactivate pathogenic viruses and microorganisms more effectively. However, this approach also led to the production of more disinfection by-products (DBPs). To ensure both disinfection efficiency and a reduction in DBP formation, new disinfection protocols are required. In this study, the disinfection efficiency, DBP amounts, and toxicity changes resulting from ozone (O3), ultraviolet (UV), chlorine (Cl2), and their combined processes were examined. The results demonstrated that the O3/UV/Cl2 combination achieved the highest disinfection efficiency. Chlorination produced the most DBPs, whereas UV treatment reduced the formation of trihalomethane (THM), halogenated ketones (HKs), haloacetic acids (HAA), dichloroacetonitrile (DCAN) and N-nitrosodimethylamine (NDMA) by 45.9%, 52.6%, 82.0%, 67.95%, and 47%, respectively. O3 also significantly reduced their production by 99.1%, 91.1%, 99.5%, 100%, and 35%. Intracellular organic matter (IOM) was identified as the primary DBP precursors, producing 2.94 times more DBPs than extracellular organic matter (EOM). The increased DBP formation during chlorination was attributed to IOM leakage and cell membrane damage, which was verified using scanning electron microscopy (SEM). The toxicities of DBPs were evaluated for six disinfection methods, revealing inconsistent results. The overall toxicities were assessed using zebrafish embryo experiments. Both evaluations indicated that chlorination alone was the least favorable method. In addition, the toxicities followed a sequence: Cl2 ≈ O3/Cl2 > O3 > O3/UV/Cl2 > UV > UV/Cl2. These findings can serve as a reference for sewage treatment plants in selecting appropriate disinfection methods to manage the COVID-19 epidemic from comprehensive perspective.

  • RESEARCH ARTICLE
    Jing Li, Dazhong Yang, Wensong Zou, Xuezhen Feng, Ranhao Wang, Renji Zheng, Siyuan Luo, Zheting Chu, Hong Chen

    ● Converting of red soil into a zeolite framework has been reported for the first time.

    ● Zeolite/biochar composite material exerts significant effects on synergetic heavy metal remediation and soil quality amendment.

    ● The observation of single atoms after soil remediation indicates single atoms may be a universal phenomenon in natural environment.

    Red soil, the most critical soil resource in tropical/subtropical regions worldwide, faces tremendous threats, including nutrient deficiency, acidification, and heavy metal contamination. There is a great demand for multifunctional eco-materials capable of modifying this situation. Herein, we used widely distributed soil and biomass to develop a zeolite/biochar composite for synergistic red soil remediation and amendment. With the composite material, the Pb2+ and Cd2+ remediation efficiencies reached 92.8% and 92.9%, respectively, in stems under optimal conditions. Moreover, the acidity and nutrient deficiency conditions of red soil significantly improved. The atomic-scale interaction mechanism during the remediation and amendment process was elucidated with complementary characterization methods, which revealed that in the zeolite/biochar composite material, zeolite contributes to long-term heavy metal remediation effects. Simultaneously, biochar is responsible for soil quality amendment and short-term heavy metal remediation. Furthermore, for the first time, single-atom heavy metal ions were observed on biochar during the remediation process, indicating the broad distribution of single atoms in the natural environment.

  • RESEARCH ARTICLE
    Daniela M. Pampanin, Daniel Schlenk, Matteo Vitale, Pierre Liboureau, Magne O Sydnes

    ● Most prescribed PPCP concentrations were measured in WWTP influent and effluent.

    ● The WWTP removal efficacy was above 90% for 12 out of 22 PPCPs.

    ● The use of bioassays was successful in evaluating the WWTP effluent impact.

    ● There was no risk due to the WWTP discharge related to the 30 selected PPCPs.

    ● DREAM simulation provided useful info about the WWTP discharge plume distribution.

    Concerns related to environmental risks associated with pharmaceuticals and personal care products (PPCPs) have led researchers to seek methods for assessing and monitoring these contaminants in the aquatic environment. Identifying and validating risk assessment tools that can evaluate ecological concerns and risks associated with PPCPs is critical. Herein, the suitability of a dose-related risk and effect assessment model, which estimates predicted environmental concentrations and allowed comparisons with predicted no effect concentrations determined, in combination with in vitro analyses of the whole effluent toxicity, was verified for the characterization of a PPCP hazard. Concentrations of the most utilized PPCPs in Norway were measured in influent and effluent samples and used to parameterize the fate model.

     Greater than 90% removal was attained for 12 out of 22 detected PPCPs. Removal was not dependent on the class or the concentration of the specific substance and varied between 12% and 100%. The PPCPs detected in the discharged wastewater were utilized to assess individual contributions to the risk of the effluent, and no risk was identified for the targeted 30 PPCP. The simulations provided valuable information regarding the discharge plume distribution over time, which can aid planning of future environmental monitoring investigations.

     Bioassays (using fish liver cells, PLHC-1) were used for assessing overall effluent toxicity, through cell viability, production of reactive oxygen species, and ethoxyresorufin-O-deethylase (EROD) activities.

     The present study may allow regulators to use risk-based strategies over removal criteria for monitoring studies and confirms the importance to take PPCP contamination into consideration when establishing environmental regulations.

  • RESEARCH ARTICLE
    Wanlu Zhu, Rui Xiao, Min Xu, Wenbo Chai, Wenlong Liu, Zhengyu Jin, David Ikumi, Huijie Lu

    ● Formate addition led to more abundant and active anammox bacteria in community.

    ● FISH–NanoSIMS identified Ca. Brocadia and Desulfobacillus as main formate utilizers.

    ● Anammox bacteria were key players in formate uptake and partial denitrification.

    ● Formate was assimilated by Ca. Brocadia via the Wood–Ljungdahl and rGly pathways.

    Desulfobacillus could provide necessities e.g., folate to support Ca. Brocadia growth.

    The addition of traditional carbon sources (e.g., acetate) could favor heterotrophic overgrowth in partial denitrification coupled with anammox (PD–A) systems, thus hindering the performance and stability of this novel wastewater nitrogen removal technology. Therefore, it is necessary to develop an effective, environmentally friendly, and inexpensive alternative. This study demonstrated the potential of formate to enhance the performance and community stability of PD–A under mainstream conditions. In a laboratory-scale biofilm reactor, formate addition (COD/NO3–N = 1.75) improved nitrogen removal efficiency (from 72.1 ± 3.5% to 81.7 ± 2.7%), EPS content (from 106.3 ± 8.1 to 163.0 ± 15.5 mg/gVSS) and increased anammox bacteria growth (predominantly Candidatus Brocadia, from 29.5 ± 0.7% to 34.5 ± 5.4%) while maintaining stable heterotrophs dominated by methylotrophic Desulfobacillus. FISH–NanoSIMS revealed a formate uptake using Ca. Brocadia and Desulfobacillus, with Ca. Brocadia being the major contributor to partial nitrate reduction to nitrite. Desulfobacillus can synthesize diverse hydrophobic amino acids and provide key nutrients for Ca. Brocadia. To achieve comparable nitrogen removal, the cost of the formate-driven PD–A process should be 11.2% lower than that of acetate. These results greatly enrich our understanding of C1 metabolism represented by formate in anammox communities and its application in the context of coupling partial denitrification–anammox toward enhanced nitrogen removal in global wastewater treatment systems.

  • RESEARCH ARTICLE
    Xinyan Xiao, Chenlan Chen, Haoran Li, Lihua Li, Xin Yu

    ● The maximum coliforms concentration increased by 2 Logs during rainfall.

    ● Culturable bacterial concentrations had a delayed increase during precipitation.

    ● DOC concentration was the main impact factor for the microbial characteristics.

    ● Culturable bacteria concentrations in waters could recover to pre-rainfall levels.

    Climate change leads to an increase in both the frequency and intensity of extreme precipitation. Surface runoff generated by extreme precipitation has a significant impact on water. However, the impact of persistent precipitation on surface water quality is easy to neglect, due to its prolonged duration and lower-intensity rainfall. This study established eight sampling points within selected surface waters to observe the variation of microbial characteristics in a typical persistence precipitation event. The primary difference between Furong Lake (FL) and Chengqian Reservoir (CR) was: the concentrations of dissolved organic carbon (DOC) were 21.3 ± 0.7 and 8.3 ± 1.5 mg/L in FL and CR, respectively. The concentrations of R2A culturable bacteria and coliforms were 104.57 and 101.58 colony-forming units (CFU)/mL in FL, and were 105.46 and 102.64 CFU/mL in CR, respectively. During precipitation, the maximum increase concentrations of R2A, NA culturable bacteria, and coliforms were 100.75, 101.30, and 102.27 CFU/mL in FL, respectively. Furthermore, microbial concentration and rainfall did not increase simultaneously, and a delay phenomenon was observed in the increasing microbial concentrations. Through analyzing the concentration change trends and correlation of various water quality indicators during persistent precipitation, the significant correlation between the DOC concentration and the changes in the dominant species of microbial community structure was found in this study (p < 0.05). For example, as the DOC concentration declined, the abundance of hgcl_clade and CL500-29_marine_group increased. Consequently, although persistent precipitation might not obviously alter the water quality visibly, it could still pose potential microbial risks.

  • REVIEW ARTICLE
    Xiaolong Yao, Kuan Wan, Wenxin Yu, Zheng Liu

    ● Water vapor’s effect on VOC adsorption in various porous carbons was investigated.

    ● How adsorbent and adsorbate properties affect moist VOC adsorption was studied.

    ● The challenges of using carbon materials for moist VOC adsorption were addressed.

    ● Theoretical and technical guidance on efficiently purifying moist VOC gases is given.

    Volatile organic compounds (VOC) have been proven to cause considerable harm to both the ecological environment and human health. Anthropogenic VOC emissions are primarily generated by the industrial sector. The utilization of porous carbon as an adsorbent has emerged as an effective method for the efficient removal of VOC from industrial sources. However, during the actual production processes, VOC exhaust gases are often mixed with water vapor, which poses challenges for adsorption purification. This review provides a comprehensive overview of the remarkable advancements in various carbon materials in terms of their ability to adsorb both VOC and water vapor. Additionally, it systematically summarizes the influence of surface groups on adsorbents and the molecular properties of VOC on their adsorption by carbon materials. Furthermore, this review introduces the mechanism underlying adsorption-adsorbent interactions and discusses the construction of models for adsorbing water vapor and VOC. The challenges associated with the application of carbon materials for VOC adsorption in humid environments are also addressed. This review aims to offer theoretical and technical guidance for the effective purification of moist VOC waste gases emitted from industrial sources, thereby achieving precise control of VOC emissions.

  • RESEARCH ARTICLE
    Boning Deng, Yachen Li, Lifeng Zhu, Yuwei Zhou, Aonan Sun, Jingjing Zhang, Yixiang Wang, Yuxi Tan, Jiajun Shen, Yalin Zhang, Zan Ding, Yunquan Zhang

    ● A national cohort to assess nexus between cognition function and PM2.5 constituents.

    ● Cognitive impairment was related to individual and joint exposure to PM2.5 constituents.

    ● BC displayed the highest negative effect on PM2.5-related cognitive impairment.

    ● Female, younger, and well-educated individuals were more vulnerable.

    Nationwide longitudinal evidence linking cognitive decline with exposure to fine particulate matter (PM2.5) constituents remains scarce in China. By constructing a dynamic cohort based on the China Health and Retirement Longitudinal Study, we aimed to assess individual and joint associations of PM2.5 constituents with cognitive function among middle-aged and older adults in China. Linear mixed-effects models incorporated with quantile-based g-computation were applied to investigate individual and joint associations of long-term exposures to PM2.5 constituents with cognitive function. Among 13,507 respondents, we evaluated 38,950 follow-up records of cognitive function tests. Declines in global cognitive score associated with an interquartile range (IQR) increase in exposure were −1.477 (95% CI: −1.722, −1.232) for nitrate, followed by −1.331 (−1.529, −1.133) for ammonium, −1.033 (−1.184, −0.883) for sulfate, −0.988 (−1.144, −0.832) for organic matter and −0.822 (−0.946, −0.699) for black carbon. An IQR-equivalent increase in joint exposure to these PM2.5 constituents was associated with a decline of −1.353 (−1.659, −1.048) in global cognitive score. Female, younger, and well-educated individuals were at greater vulnerability to cognitive impairment related to individual and joint exposure to PM2.5 constituents. This study suggested that later-life exposures to PM2.5 constituents were associated with cognitive decline in middle-aged and older adults in China.

  • RESEARCH ARTICLE
    Jian Lu, Jun Wu, Cui Zhang, Jianhua Wang, Xia He

    ● The highest absolute abundance of ARGs in seawater reached 2.3 × 104 copies/mL.

    ● Multidrug resistance genes were major ARGs in seawater of many sites.

    ● Insertion sequences were the dominant MGEs in seawater.

    Prochlorococcus _MIT9313 and Clade_la were the predominant genus in seawater.

    ● Anthropogenic activities had important effect on ARGs and MGEs.

    Antibiotic resistance genes (ARGs) might have great effect on ecological security and human health. Oceans are important reservoirs that receive tremendous amounts of pollutants globally. However, information on the proliferation of ARGs in seawater is still limited. This study performed field sampling to investigate the occurrence and distribution of ARGs in seawater of the South China Sea, which is the deepest and largest sea in China. The results showed that the total absolute abundances of ARGs in seawater samples ranged from 2.1 × 103 to 2.3 × 104 copies/mL, with an of 5.0 × 103 copies/mL and a range of 2.2 × 103–1.8 × 104 copies/mL for those with mobile genetic elements (MGEs). Genes resistant to multidrug, aminoglycoside, tetracycline, and fluoroquinolone antibiotics accounted for 77.3%–88.6% of total ARGs in seawater. Proteobacteria and Cyanobacteria represented 32.1%–56.2% and 30.4%–49.5% of microbial community, respectively. Prochlorococcus_MIT9313 and Clade_la were the prevalent genera in seawater of the South China Sea. Complex co-occurrence relationship existed among ARGs, MGEs, and bacteria. Anthropogenic activities had critical influence on ARGs and MGEs. Hospital wastewater, wastewater treatment plant effluent, sewage, aquaculture tailwater, and runoff were determined as the important sources of ARGs in seawater of the South China Sea based on positive matrix factorization analysis.

  • RESEARCH ARTICLE
    Felix Grimberg, Thomas M Holsen, Sujan Fernando, Siwen Wang

    ● Biotransformation of 6:2 fluorotelomer sulfonate (6:2 FTS) can occur in S-rich media.

    ● Both stable and intermediate products were identified from the biotransformation of 6:2 FTS.

    ● Mass loss due to volatile intermediate PFASs can be theoretically estimated.

    ● Volatile PFAS may represent a significant portion of 6:2 FTS transformation products.

    Biotransformation of 6:2 fluorotelomer sulfonate (6:2 FTS) by two species of white-rot fungi, Pleurotus ostreatus (P. ostreatus) and Trametopsis cervina (T. cervina), was investigated in a sulfur-rich medium designed to stimulate production of lignin-degrading enzymes. Degradation of 6:2 FTS was observed by T. cervina over the study period of 30 d, but not by P. ostreatus. Biotransformation rates were comparable to those found in other studies investigating mixed culture degradation in non-sulfur limiting media, with approximately 50 mol% of applied 6:2 FTS removed after 30 d. Stable transformation products were short-chain perfluorocarboxylic acids (PFCAs), including PFHxA (2.27 mol%), PFPeA (0.24 mol%), and PFBA (0.28 mol%). The main intermediate products include 5:2 sFTOH (16.3 mol%) and 5:3 FTCA (2.99 mol%), while 6:2 FTCA, 6:2 FTuCA, and 5:2 ketone were also identified at low levels. Approximately 60 mol% of detected products were assigned to the major pathway to 5:2 ketone, and 40 mol% were assigned to the minor pathway to 5:3 FTCA. The overall molar balance was found to decrease to 75 mol% by Day 30, however, was closed to near 95 mol% with a theoretical estimation for the volatile intermediates in the headspace, 5:2 ketone and 5:2 sFTOH. The different capabilities of the two white-rot fungal species for 6:2 FTS biotransformation in sulfur-rich media suggest that the enzyme processes of T. cervina to de-sulfonate 6:2 FTS may be unrelated to sulfur metabolism.

  • RESEARCH ARTICLE
    Yingying Liu, Hanbing Li, Sha Chen, Lantian Zhang, Sumei Li, He Lv, Ji Gao, Shufen Cui, Kejun Jiang

    ● A WECA model evaluates water withdrawal and WEQ of typical EVRs’ transition.

    ● Synergetic pathways of water-energy-carbon to carbon neutrality are proposed.

    ● Electricity production can escalate WEQ due to industrial transition.

    ● Limited effects from zero-carbon transition on improving water environment quality.

    Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide, especially in ecologically vulnerable regions (EVRs). In this study, to explore the synergistic pathways in an EVR, a water-energy-carbon assessment (WECA) model was built, and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional transition. Shaanxi Province was chosen as the representative EVR, and Lower challenge (LEC) and Greater challenge (GER) scenarios of zero-carbon transition were set considering the technological maturity and regional energy characteristics. The results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water quality. In the LEC scenario, the energy demand and CO2 emissions of Shaanxi in 2060 will decrease by 70.9% and 99.4%, respectively, whereas the water withdrawal and freshwater aquatic ecotoxicity potential (FAETP) will only decrease by 8.9% and 1.6%, respectively. This could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition measures. The GER scenario showed significant growth in water withdrawals (16.0%) and FAETP (36.0%) because of additional biomass demand. To promote the synergetic development of regional transition, EVRs should urgently promote zero-carbon technologies (especially solar and wind power technologies) between 2020 and 2060 and dry cooling technology for power generation before 2030. In particular, a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended.