Environmental Science: Water Research & Technology最新文献

The integration of point-of-care diagnostics in SARS-CoV-2 wastewater-based epidemiology signifies a substantial leap forward in disease surveillance and monitoring. Various innovative methods have been explored for the detection of SARS-CoV-2 in wastewater samples, each with its unique advantages and applications. Loop-mediated isothermal amplification (LAMP) has emerged as a prominent technique due to its sensitivity, rapidity, and simplicity. It amplifies pathogen genetic material without the need for a thermal cycler, making it suitable for point-of-care detection. Pairing microfluidic technology with LAMP enables swift and automated analysis directly on a chip. Additionally, paper-based devices offered a cost-effective and straightforward approach for LAMP-based detection, particularly beneficial in resource-limited settings. Combining LAMP with CRISPR/Cas technology enhances specificity and sensitivity, crucial for variant-specific detection like VarLOCK (variant-specific SHERLOCK). Aptamer-based electrochemical chips offer high specificity and stability, making them suitable for wastewater analysis. By integrating aptamer technology with filtration and purification systems, detecting SARS-CoV-2 on-site in wastewater becomes feasible, offering a practical solution for monitoring viral transmission. These methods showcase the diverse approaches in SARS-CoV-2 detection through wastewater-based epidemiology, promising effective disease surveillance. In this review, we will summarize these recent advancements in point-of-care diagnostics for SARS-CoV-2 wastewater-based epidemiology and explore their potential applications beyond SARS-CoV-2.

This work investigates the water impact of carbon capture technologies employed in coal and natural gas power generation, viz. the integrated gasification combined cycle, oxy-fuel combustion, solid oxide fuel cells and solvent-based post-combustion. The water impact per CO₂ avoided (WICa) metric was developed to understand the tradeoff between water usage and global warming potential, and additionally as a decision-making tool. It relates the impact on available water resources to greenhouse gas reduction over the cradle-to-plant-exit lifecycle by leveraging existing metrics, including the water impact index (WII), water withdrawal, water consumption, water quality, and water scarcity index (WSI). The results show that some carbon capture technologies increase the overall water usage of power generation plants, thereby increasing the water impact per CO₂ avoided. Solid oxide fuel cells and oxy-fuel technology, though not mature in comparison with post-combustion capture, have the least water impact per CO₂ avoided. Furthermore, water withdrawal and consumption are shown to trend with the WII in specific scenarios, implying that, in the absence of water quality and WSI data, the metric's use as a stakeholder decision-making tool remains. The potential to reduce global warming via carbon capture technologies in the power generation industry can create additional water resource challenges for countries if not carefully considered.

Artificial sweeteners, which potentially pose threats to ecosystems, are prevalent emerging contaminants in aquatic environments. This study explored the efficacy and mechanism underlying the degradation of saccharin by thermally activated persulfate treatment (thermal/persulfate) for the first time. Saccharin degradation followed pseudo-first-order kinetics, with a k_obs value of 0.023 min⁻¹ under the following conditions: [saccharin]₀ = 5 mg L⁻¹, [persulfate]₀ = 100 mg L⁻¹, temperature = 70 °C and solution pH = 7.0. Optimal saccharin degradation occurred under neutral and weakly acidic pH conditions (pH 7 and 5), and the calculated apparent activation energy of saccharin was 113.3 kJ mol⁻¹. The results from the scavenger experiments and electron paramagnetic resonance identification revealed that SO₄˙⁻ and ·OH were the predominant radical species involved in saccharin degradation, with ·OH likely playing the major role. HCO₃⁻, NO₃⁻, and dissolved organic matter competed with saccharin for free radicals, decreasing the saccharin degradation rate; however, Cl⁻ had a positive effect. Saccharin degradation involved monohydroxylation and dihydroxylation and produced TP1 and TP2, respectively. During treatment, 35% TOC reduction was achieved, and the Microtox® toxicity initially increased and then decreased, suggesting that saccharin and its transformation byproducts undergo mineralization and detoxification. The saccharin degradation rate was lower in actual water matrices than in deionized water. In conclusion, this work comprehensively investigated the degradation of saccharin by thermally activated persulfate treatment for future applications in water/wastewater treatment.

The MIL-100(Fe) was employed for the remediation of toluene-contaminated water. The MIL-100(Fe) samples synthesised for this work exhibit high thermal (300 °C) and chemical (pH range 2–10) stability. Adsorption kinetics and isotherms were fitted to the Elovich and Temkin models. The pH of the aqueous sample containing Toluene impacted the adsorption capacity of MIL-100(Fe) through modulation of the MOF ζ potential. As a result, we concluded that MIL-100(Fe) is most effective at adsorbing toluene in the 6–10 pH range, a finding that underscores its potential in water treatment. The maximum Langmuir adsorption capacity of 318.48 mg g⁻¹ was determined. MIL-100(Fe) showed excellent adsorption–desorption performance and stability; hence, it can be used repeatedly without losing toluene adsorption capacity. FT-IR spectra suggest that π–π interactions serve a crucial role during toluene adsorption, further confirming the effectiveness of MIL-100 (Fe) in water treatment.

In light of the pressing challenge of global plastic and water pollution, this study seeks a single solution by exploring the remarkable potential of rice starch (RS)–graphene oxide (GO) bio-nanocomposite films. RS–GO composite films were prepared with varying GO concentrations. As the GO weight percentage was increased from 0 wt% to 1 wt% of starch, the ultimate tensile strength of the composite was seen to increase by 438%, whereas a marginal decrease of 29% in elongation was observed. Reinforcement of GO into the starch film also helped to enhance the melting temperature because of the strong hydrogen bond formation between RS and GO sheets. Apart from the enhanced mechanical and thermal stability of the prepared composite films, they also exhibited antibacterial properties against both Gram-positive and Gram-negative bacterial strains, encouraging their use in food packaging and storage industries. In addition, the use of RS–GO biocomposites as adsorbent materials for lead removal from wastewater was also explored. As the GO concentration was increased in the composite film, the Pb(II) ion removal efficiency (RE) also increased, with a maximum RE of 99% observed for 5 wt% GO film from 10 ppm Pb(II) water solution. In conclusion, the ability of RS–GO bio-nanocomposites to address plastic and water pollution adds to their value as eco-friendly materials.

Perfluoroalkyl acids (PFAAs) such as perfluorooctanoic acid (PFOA) have been referred to as “forever chemicals” and are toxic and bioaccumulative. Previous studies have indicated that the defluorination of PFOA is incomplete by various advanced reductive processes. In this study, we proposed combining sulfite (SO₃²⁻) with iodide (I⁻) for the advanced reduction of PFOA under vacuum ultraviolet (VUV) radiation. The degradation and defluorination ratios of PFOA reached 100% within 30 min and 99.2% within 6 h, respectively. Hydrated electrons (e_aq⁻) and VUV photolysis are major contributors to PFOA removal. The VUV/SO₃²⁻/I⁻ system was superior to UV/SO₃²⁻/I⁻ for PFOA decomposition with a synergistic factor of 1.36 and a higher e_aq⁻ yield. The optimal dosage of I⁻ could be reduced by half owing to the stronger absorption coefficient under VUV radiation. HCO₃⁻, Cu²⁺, and humic acid could inhibit the decomposition of PFOA. Fe³⁺ and SO₄²⁻ had slight and negligible effects on the performance of the VUV/SO₃²⁻/I⁻ process, respectively. We determined the most active sites for nucleophilic attack by utilizing the Fukui function indices of PFOA anions using density functional theory (DFT) calculations. C7 polyfluorinated carboxylate esters, short-chain hydrogen-containing and sulfonated intermediates were identified in PFOA degradation for the first time in the study. This study provides a feasible approach for the environmental remediation of PFOA.

In Taiwan, farmlands are polluted with metals mainly caused by irrigation water and sediments in irrigation channels. Copper (Cu) presents a major challenge in Taiwan's agricultural lands. This study investigates the potential of utilizing water bamboo (Zizania latifolia) husk-derived biochar (WBC) for the treatment of copper-contaminated irrigation water and soil amendment. The BET-SSA for WBC that is produced at 600 °C is 192 m² g⁻¹ and the pore volume is 0.174 cc g⁻¹. The FTIR spectrum of WBC exhibits several functional groups, such as phosphate, carboxylate (–COO), or aromatic (CC) that can contribute to biochar alkalinity. The point of zero charge (pH_PZC) of WBC is determined to be 2.7. The optimum adsorption of copper by WBC occurs at pH 5. Copper adsorption by WBC fits well with pseudo-second-order kinetics and the Langmuir isotherm, which demonstrates that chemisorption and monolayer adsorption are the dominant mechanisms for copper removal. The maximum Cu²⁺ adsorption capacity of WBC is 144.9 mg g⁻¹, which is much higher than those of many existing reports. The addition of 1 to 5% (wt/wt) WBC neutralizes acidic soil pH effectively, making it suitable for water bamboo cultivation.

Hydrothermal technology emerges as a cutting-edge approach for utilizing liquid effluent and waste biomass into valuable products. Simulated zinc metal effluent (Zn-1758 ppm) and real zinc electroplating effluent (Zn-765 ppm and Cr-506 ppm in high concentration) with pine needles as an adsorbent, aiming for zero waste discharge were investigated. A comprehensive study was performed to analyze the impact of several critical parameters, such as temperature (100–600 °C), time (0–60 min), and biomass to simulated metal effluent ratio (1 : 4 to 1 : 10), on metal recovery from metal-contaminated wastewater. The metal ions in the effluent are bound to the carbon matrix and reduced to lower valence metal oxide or pure metal during the hydrothermal process, later recovered as a metal–carbon composite. Parameters such as temperature and time positively impact the recovery of metal ions from wastewater. Under operating conditions of 400 °C, 30 minutes, and a biomass-to-effluent ratio of 1 : 100 utilizing pine needle-infused real zinc electroplating effluent, a recovery exceeding 99.9% of metal ions has been attained, concurrently yielding a metal loading of 303.4 mg g⁻¹ of the carbon composite. Under similar operating conditions with pine needles and simulated zinc metal effluent, a maximum metal loading of 623.3 mg g⁻¹ of carbon composite was achieved. The generated carbon composite has nanometals with a quasi-spherical morphology and a significant surface area (max: 221.1 m² g⁻¹), rendering it suitable for fabricating sensors and energy storage devices.

The evaluation of COVID-19 policy effectiveness on university campuses, particularly in mitigating spread to neighboring cities (i.e., “campus spill-over”), is challenging due to asymptomatic transmission, biases in case reporting, and spatial case reporting limitations. Wastewater surveillance offers a less biased and more spatially precise alternative to conventional clinical surveillance, thus providing reliable data for university COVID-19 policy evaluation. Wastewater surveillance data spanning the academic terms from Fall 2020 through Spring 2022 was used to evaluate the impact of university COVID-19 policies. During the campus closure to external visitors (09/21/2020–9/15/2021), campus viral concentrations and variant compositions were dissimilar from those of the host and neighboring cities (MAPE = 0.25 ± 0.14; Bray–Curtis = 0.68 ± 0.1, respectively), indicating relative isolation of the campus from its surroundings. Upon the campus reopening to visitors (9/15/2021–2/27/2022), the viral concentrations and variant compositions matched more closely with the host and neighboring cities (MAPE = 0.21 ± 0.1; Bray–Curtis = 0.14 ± 0.08, respectively). Furthermore, post-lifting of campus and state mask mandates (2/27/2022–6/12/2022), the campus, host and neighboring city viral concentrations and variant compositions became indistinguishable (MAPE = 0.06 ± 0.02; Bray–Curtis = 0.07 ± 0.05, respectively). This data suggests that university COVID-19 policies effectively prevented campus-spill over, with no significant contribution to COVID-19 spread into the surrounding communities. Conversely, it was the surrounding communities that led to the spread of COVID-19 onto the campus. Therefore, wastewater surveillance proves instrumental in monitoring COVID-19 trends in surrounding areas, aiding in predicting the impact of easing campus restrictions on campus health.

We would like to take this opportunity to thank all of Environmental Science: Water Research & Technology's reviewers for helping to preserve quality and integrity in chemical science literature. We would also like to highlight the Outstanding Reviewers for Environmental Science: Water Research & Technology in 2023.