ACS ES&T water最新文献

Riparian zones act as critical “sinks” for nitrogen transformation and “buffers” for nitrogen removal in reservoirs. The operation of hydropower reservoirs significantly alters water levels in these zones and impacts the biogeochemical transformation of nitrogen. This is primarily driven by bacteria residing in the sediments of riparian zones. However, the impact of water level alteration on the bacterial community and its nitrogen-transformation function remains unclear. This study investigates whether the changes in water contents or the water-level fluctuations resulting from reservoir operation more profoundly affect bacterial functioning for nitrogen transformation and whether the observed differential functioning arises from community dynamics. Through a long-term field investigation in a reservoir on the upper Mekong River, we discovered that fluctuation frequency, rather than changes in water contents, significantly increased the abundance of genes encoding nitrogen-transformation enzymes, especially those related to anaerobic ammonia oxidation. These fluctuations created conditions that maximized the bacterial potential for nitrogen removal without significantly altering the community structure. Our findings suggest that the differential functioning observed is instead driven by ecological strategies within the bacterial community rather than by community dynamics. This offers new insights into optimizing reservoir management for improved nitrogen removal.

Endocrine disrupting compounds (EDCs) are emerging environmental pollutants that cause detrimental effects on aquatic organisms and humans despite being present in the environment at trace level. There is insufficient detailed baseline data and ecological risk assessments in river basins globally, despite their ubiquity in freshwater environments. Thus, this study investigated the abundance, distribution, and ecological risks of EDCs in surface water of tropical river basin, using the combination of solid phase extraction and liquid chromatography-tandem mass spectrometry. Approximately, seven EDCs were detected, encompassing bisphenol A (BPA), bisphenol S, bisphenol F (BPF), perfluorooctanesulfonate, perfluorooctanoic acid, 17α-ethynylestradiol (EE2), and 17β-estradiol (E2) in surface water of Selangor River Basin. BPF was observed to be the most prevalent compound at 1098.40 ng/L and was followed by BPA (358.05 ng/L). Human activities, including industrial, commercial, and residential waste discharge into tributaries and lower streams, greatly influence the prevalence of EDCs in the Selangor River Basin. EE2 and E2 had significant ecological risks (risk quotient > 1) and may possess detrimental effects on freshwater organisms. This study addresses the urgent need for baseline data on EDC prevalence and ecological risks for regulatory measures and mitigation strategies to protect aquatic ecosystems.

The critical concerns regarding hazardous organic dyes, which cause significant harm to human health and environmental sustainability, require immediate attention. This study demonstrates the development of an innovative disposable electrochemical sensor that employs thiosulfate-modified graphitic carbon nitride (gC₃N₄-S₂O₃) nanosheets as class-selective and cost-efficient flexible plastic electrodes for the remote, handheld monitoring of cationic dyes─a class of perilous water-soluble organic pollutants. This sensor is capable of detecting several cationic dyes, such as methylene blue (MB), rhodamine B (RhB), and thionine (Th), simultaneously in drinking water. Modified gC₃N₄-S₂O₃ nanosheets were produced using a straightforward sonochemical-assisted method, followed by thermal condensation treatment. The produced material is characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The DPV measurements span a wide range of dye concentrations, ranging from 1 nM to 1 mM. Under optimized conditions, the electrochemical gC₃N₄-S₂O₃ sensor exhibits excellent performance, with picomolar limits of detection (LOD), i.e., 118 pM for Th, 161 pM for RhB, and 209 pM for MB, respectively. The gC₃N₄-S₂O₃ sensor utilizes electrostatic interactions to distinguish between cationic and anionic dyes and is capable of simultaneously detecting several cationic dyes. The gC₃N₄-S₂O₃ sensor also demonstrates enhanced capability to detect several cationic dyes in solutions, complex mixtures, and drinking water samples, indicating minimal interference from ionic species inherently present in drinking water. This work highlights the potential of gC₃N₄-S₂O₃ sensors for application in monitoring and remediation of the environment.

Increasing water scarcity has made nontraditional water reuse a critical strategy for enhancing water supply in the United States. This study investigated public perceptions of nontraditional water reuse, particularly oil and gas–oil and gas produced water reuse, in New Mexico, using valid responses from 657 statewide survey participants. Results showed substantial public support (up to 68.5%) for reusing various nontraditional water sources, including produced water. Awareness gaps were identified, particularly among younger individuals, those with lower educational attainment, and residents in less drought severe counties. Statistical analysis revealed significantly greater support for nontraditional water reuse (>74%) in severely drought-stricken counties with an average drought severity and coverage index (DSCI) >300 compared to those in milder drought conditions (>62.1%, average DSCI < 200), highlighting the influence of direct experience with water scarcity on public attitudes. Increased public awareness correlated with stronger support for reuse initiatives, highlighting the need for targeted education and outreach efforts. Concerns about the safety of produced water reuse emphasized the importance of transparent communication on treatment processes, monitoring, and regulatory oversight to ensure safe reuse. These findings offer valuable guidance for policymakers to develop effective water reuse strategies and bolster public support for sustainable water management practices.

The widespread distribution of persistent, mobile, and toxic organic chemicals (PMT) in aquatic environments poses a threat to water resources. Current mobility assessments rely on the organic carbon normalized adsorption coefficient (K_OC), but it is sometimes highly variable with sorptive phase (soil/sediment) properties. There is a common oversight that this variability causes assessment discrepancies. Herein, this variability was quantitatively evaluated based on compiled experimental K_OC data sets, which were obtained under OECD guidelines. The results show that both the average discrepancy rate and relative difference rate are nearly half of those of the substances among recent reports. The underlying reasons are high K_OC variability and poor-quality assessment data sources which fail to capture this variability. The variation in K_OC values for one-third of the charged organic compounds is more than 1 order of magnitude, around twice higher than that of neutral organic compounds. The K_OC values from common integrated databases or available quantitative structure–property relationships all have almost orders of magnitude differences compared with data sets, especially for charged compounds. The insights presented here have significant value in the future development of a proper mobility assessment.

The rapid proliferation of saxitoxin (STX)-producing cyanobacteria in freshwater ecosystems poses an emerging threat to global drinking water security. STXs (STX), produced by these harmful algal blooms, are a class of potent neurotoxic alkaloids that exhibit resistance to conventional water treatment processes like oxidation. Adsorption using carbon-based materials is recommended for STX removal, but current adsorbents have limited efficacy. Here, we demonstrate that mesoporous graphene nanoplatelets (GnPs) are a superior adsorbent for STX, outperforming granular activated carbon (GAC) and other benchmarks in both kinetics and capacity. GnPs achieved a 93.5-fold higher adsorption capacity and over 6-fold faster kinetics compared to GAC. The exceptional performance of GnPs is attributed to their high surface area, favorable surface chemistry, and optimized pore structure that facilitate rapid and extensive STX adsorption through π–π interactions, electrostatic attraction, and intraparticle diffusion. Mechanistic studies revealed a critical role of solution conditions, with higher pH and lower ionic strength enhancing STX removal by promoting electrostatic interactions. GnPs also demonstrated excellent performance in simulated field water, maintaining >90% removal within 1 h even in the presence of competitive organics. This study highlights the immense potential of GnPs as an advanced adsorbent for mitigating the rising threat of STX contamination in drinking water.

Novel graphene-based adsorbents demonstrate exceptional removal of freshwater saxitoxins, offering promising solutions for emerging water contaminant treatment.

Disinfection of swimming pools and hot tubs (pools/spas) are necessary to prevent outbreaks and exposure to waterborne pathogens from water recreation. However, harmful disinfection byproducts (DBPs) from heavy chlorine usage continue to be a growing concern. Chlorine-based disinfectants also react with human inputs like sweat, urine, cosmetics, sunscreen, etc., that are introduced in a pool/spa, further increasing the severity of the DBP problem. We reviewed the current status of water disinfection technologies in the pool/spa industry and summarize the methods, trends, advantages, and disadvantages from a health and consumer viewpoint. Market research and face-to-face interviews were also accomplished with 100 industry experts and end-users in the US. We then integrate the literature findings in parallel with these market insights. Overall, we conclude the future of water recreation is trending away from high dosage chlorine-based solutions to disinfect swimming water and turning to alternatives with better sustainability and safety in mind. Lastly, we discuss the future directions of these technologies with current and past trends, offering insights to where research and development should be focused for both the user’s health and overall experience.

High-frequency and high-precision dissolved oxygen (DO) monitoring is essential for lake health assessment, but it is limited by equipment and methods. This study developed a novel ground-based hyperspectral proximal sensing system (GHPSs) combined with machine learning methods for continuous monitoring of DO with an observation interval of 20 s. Five machine learning and deep learning models were calibrated and validated to estimate DO based on four combination scenarios of the GHPSs reflectance of 420–830 nm, chlorophyll-a (Chl-a), and water temperature (WTR). The results showed that a support vector machine model was preferred for DO estimation with satisfactory accuracy (R² = 0.84, mean absolute percentage error = 0.12, and root mean square error = 1.15 mg/L) based on 11,131 in situ measurements. Multitemporal changes of DO concentration in Lake Taihu were obtained from October 2021 to December 2023 by applying the model, which suggested that the surface of Lake Taihu was hypoxic in 2.1% out of 754 days. Finally, the potential significance of monitoring real-time DO dynamics was elaborated under global warming. This study highlights the effectiveness, accuracy, and high frequency of novel GHPSs in real-time DO monitoring, which is crucial for predicting and early warning of lake pollution.

Many systems have interconnected relationships, including those that consume energy to produce water and those that consume water to produce energy. These interconnections constitute the water–energy nexus, aspects of which have been the subject of recent study. Several visualizations of the water–energy nexus are available; however, many do not readily portray trade-offs between different water–energy technologies. In this Perspective, we present several visualizations and/or approaches that can help decision-makers better understand nexus trade-offs. First, a quadrant graph with water produced/consumed (x-axis) and energy produced/consumed (y-axis) shows how fossil fuel and renewable energies are related to one another within the nexus. Among other observations, the graph specifically highlights the current absence of systems that produce both water and energy. As emerging technologies such as anaerobic wastewater treatment become more prevalent, stakeholders can use the quadrant graph to examine how each compares to existing water–energy technologies. Finally, complementary to the quadrant graph, a figure presenting the normalization of energy produced to water consumed highlights the dominance of wind power over other technologies and how evaporative losses impact hydropower. Each of these visualizations and/or approaches can help decision-makers and stakeholders make improved decisions regarding the use of technologies within the water–energy nexus.