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The main factors governing the formation of river water chemistry on the northwestern slope of the Crimean Mountains were studied, and the ecological conditions of river water are estimated. The data used in the study have been collected during summer field studies in 2003–2022. River water chemistry is not stable and varies depending on weather conditions in individual years and anthropogenic impact. The effect of geological–hydrogeological conditions on the macro- and microcomponent composition in the natural water of the region is demonstrated. The concentrations of chemical elements in the surface waters in the Bodrak River basin are proposed to be used as natural (background) concentrations of chemical elements in river waters not experiencing anthropogenic impact. [ABSTRACT FROM AUTHOR]

The industrialization of Nigeria for economic development has led to the pollution of the ecosystem by polycyclic aromatic hydrocarbons (PAHs) through anthropogenic activities. PAHs are toxic organic compounds, ubiquitous and can pose a health-related environmental risk. The sources, concentration, and health risk assessments of PAHs in underground and surface water in Nigeria were reviewed in this study. Previous studies were extracted from research databases (PubMed, Google Scholar, ResearchGate, and Scopus) and appropriately screened. The PAH levels found in the studies were at low and high concentrations and could pose a health-related risk to the populace. The values ranged from ND–17,762 to ND–450,000 µg/L for underground and surface water, respectively. Also, the sources of the PAHs were pyrogenic and petrogenic. The cancer risk assessment values of PAHs in the water recorded low to high-risk values via dermal and ingestion exposure routes to humans. The hazard index (HI) values of the non-carcinogenic risk observed no risk except for only one study. It is recommended that proper monitoring, awareness, and strict enforcement of regulatory laws be implemented to prevent water and environmental pollution by this toxic compound. [ABSTRACT FROM AUTHOR]

Diverse microbial communities play a crucial role in maintaining the proper functioning of river ecosystems and are considered important indicators of river water quality. Although the Seine River being heavily impacted by human activities, little is known about the microbial communities in its surface waters. In order to monitor water quality and promote sustainable use, we studied its microbial diversity using high-throughput sequencing technology, and explored their relationships with physico-chemical properties. The dominant phyla identified were Proteobacteria, Actinobacteriota, Bacteriodota, and Cyanobacteria. The presence of the Alphaproteobacteria and Gammaproteobacteria indicates that the Seine River water nutrient profile is mainly determined by the recalcitrant organic compounds present in WWTP effluents. Bacterial diversity showed significant temporal variability with a highly significant difference in bacterial composition between 2020 and 2021, probably due to variations in water flow favoring Cyanobacteria growth. Summer displayed higher microbial activity and abundance than autumn, attributed to temperature and orthophosphate content. Spatial variation in bacterial composition was observed between sites upstream and downstream of Paris, as well as before and after of the Seine Valenton-WWTP, subject to an accumulation phenomenon and impacted by wastewater treatment. Further assessment of emerging contaminants and other pollutants is required to better understand these variations. These results provide a basic understanding of the microbial community in the Seine River, serving as a reference for assessing the impact of implementing new wastewater disinfection techniques in the near future. [ABSTRACT FROM AUTHOR]

Bioindicative methods involving the identification and counting of indicator organisms (e.g. algae) are widely used methods in the assessment of surface water quality. For this reason, the purpose of this paper was automatic image analysis using the YOLO v8 deep learning neural network, directed at the detection of freshwater algae Cyclotella. Changes in the number of these organisms can indicate changes in the water quality and the trophic status of the reservoir, which makes automating their detection an important task. Traditionally, the detection and counting of objects in microscope images was done manually, but by using machine learning and especially neural networks, the process can be automated. YOLO (You Only Look Once) is an example of a network that, after proper training and validation, is capable of performing image detection in real time. In this study, the Roboflow object tagging tool was used to create a dataset divided into training, validation and test sets. Training of the network, validation of the model and evaluation of its metrics were carried out. The paper presents the obtained metrics of the YOLO v8 network on the validation set, such as Accuracy = 0.960, Precision = 0.964, Recall = 0.995. The presented results confirm the effectiveness of the applied method in automatic analysis of microscopic images containing algae and thus the high application potential of the method in supporting bioindication studies of surface water quality. [ABSTRACT FROM AUTHOR]

To evaluate the water quality in the Poprad, Kamienica, Dunajec river and the Łubinka stream in the Sącz agglomeration, two series of pilot studies were conducted on raw water samples, with a particular focus on both physical parameters (such as total suspended matter, turbidity, pH, and conductivity) and chemical parameters. The analysis presented increased concentrations of phosphorus, nitrogen, BOD5, COD, chlorides, sulfates, permanganate value, orthophosphates, total suspended matter, specific electrolytic conductivity (PEW), pH levels, and various elements including lithium, magnesium, manganese, potassium, sodium, calcium, and iron. No exceedance of the detection limits for individual pesticides were observed in the waters of the Poprad, Kamienica rivers and the Łubinka stream. Nevertheless, increased concentrations of the insecticide imidacloprid and the fungicide imazalil were detected in the Dunajec river. The primary factors impacting water quality in the Sącz agglomeration are the use of fertilizers, the proximity of wastewater treatment plants, and the presence of landfill sites. [ABSTRACT FROM AUTHOR]

The effluent discharge of domestic wastewater and industrial effluents into watercourses has necessitated the development of monitoring systems with the purpose of characterizing levels of pollution. Substantial levels of pollution in emerging nations have been exacerbated by rapidly growing populations and inefficient enforcement of sustainable management initiatives. The Water Quality Index (WQI) can help fill the gap between water quality reporting and monitoring by offering a simple and effective way to assimilate and communicate results from a large amount of data. WQIs are the kind of communication tools that can facilitate knowledge sharing between scholars and the general public. The degradation of natural water resources, such as lakes, streams, and estuaries, is the most significant problem facing humanity. Water that is not clean has far-reaching effects on all aspects of life. Water resource management is therefore essential if it is to maximize water quality. If data are analyzed and water quality can be predicted in advance, water pollution may be efficiently addressed. Although this subject has been the subject of numerous earlier studies, additional research is still required to fully understand the effectiveness, reliability, accuracy, and application of the present approaches to water quality management. In this research work, a comprehensive review has been conducted on water quality assessment using artificial techniques. It reviews 75 research works on water quality analysis. The data collected in each research work have been analyzed. Moreover, the type of water resource surface water, groundwater, drinking water as well has been analyzed. The parameters considered in each work are “Dissolved Oxygen (DO), Potential of Hydrogen (pH), Biochemical Oxygen Demand (BOD), Total Dissolved Solids (TDS), and Chemical Oxygen Demand (COD), chloride, hardness, alkalinity, nitrate–nitrite”. In addition, the Artificial Intelligence technique utilized for water quality analysis is also assessed. Finally, the research gaps identified in water quality detection are exhibited. [ABSTRACT FROM AUTHOR]

The study intends to bridge the lack of baseline information on microplastic (MPs) contamination in two river systems (Periyar: the longest river, lifeline of the Kerala State and Chalakudy: the fifth longest river) and hence is highly relevant. Sampling was carried out twice during December 2020 and January 2021. Elevated level of contamination was recorded at midstream sites in Chalakudy and downstream sites at Periyar. Small-sized particles (<100 µm) constituted the majority (>45%) in both river systems resulting from the disintegration of larger particles or direct release of primary MPs. Prevalence of fragment shape, accounting for ≈48–71% across all sites in both rivers, resulted from the disintegration of meso or macro plastics. Preponderance of blue-coloured particles (≈33–67%) inferred potential risk to aquatic organisms. Low-density polyethylene emerged as the dominant polymer group, originated from packaging materials and bottles. Overall abundance and recovery rate in both rivers indicate that MPs occur at all sites, irrespective of land use patterns, sourced to the degradation of abandoned fishing gears, shipping, tourism activities, and untreated waste disposal. The high risk of microplastic pollution in the study area was endorsed by polymer hazard index and coefficient of microplastic impact index. [ABSTRACT FROM AUTHOR]

The potential pollution risks and characteristics of heavy metal pollution in surface streams were assessed in a decommissioned uranium tailing. The results demonstrated that the concent of seven heavy metals in the tailing were comparatively high and were beyond the environmental quality standard limits of surface water. Correlation and enrichment factor studies demonstrated that mining operations were the main source of contamination. According to pollution evaluation indices, there was a high risk of contamination and notable enrichment and pollution features for Tl, Mo, Mn, U, and Al in the tailing. Ni and Cd were mildly contaminated and enriched. [ABSTRACT FROM AUTHOR]

E. coli and total coliforms are the most widely used indicator organisms for microbial monitoring of drinking water and recreational freshwater. In many remote and low-resource settings, however, conventional laboratory methods for quantifying these indicators are challenging or infeasible to perform due to limited access to laboratory facilities. The availability of rapid, low-cost methods for quantifying indicator organisms in freshwater samples without the need for laboratory facilities is crucial to facilitate the rapid and robust monitoring of microbial water quality in these types of settings. The global misuse and abuse of antimicrobials have contributed to the rise of antimicrobial resistance. Thus, simple culture methods are needed to detect indicators of such bacteria in freshwaters. In 2021, the World Health Organization released the Tricycle protocol to address this issue by providing guidance for culture-based detection of extended-spectrum beta-lactamase (ESBL)-producing E. coli in environmental samples. Our research goal was to compare the 100-ml sample volume ESBL E. coli quantal and enumerative commercial tests against the more complex Tricycle protocol to detect and quantify ESBL E. coli in surface waters. Both commercial tests gave results comparable with the results obtained using the Tricycle protocol, and the quantal and enumerative commercial tests were easier and faster to perform than the Tricycle protocol. [ABSTRACT FROM AUTHOR]

Per‐ and polyfluoroalkyl substances (PFAS) are a class of chemicals present in a wide range of commercial and consumer products due to their water‐repellency, nonstick, or surfactant properties, resulting from their chemical and thermal stability. This stability, however, often leads to persistence in the environment when they are inevitability released. We utilized microbial microcosms from wastewater treatment plant (WWTP) sludge to determine how employing different functional groups such as heteroatom linkages, varying chain lengths, and hydrofluoroethers (HFEs) will impact the ultimate fate of these novel PFAS structures. A suite of five novel fluorosurfactant building blocks (F7C3OCHFCF2SCH2CH2OH (FESOH), F3COCHFCF2SCH2CH2OH (MeFESOH), F7C3OCHFCF2OCH2CH2OH (ProFdiEOH), F7C3OCHFCF2CH2OH (ProFEOH), and F3COCHFCF2OCH2CH2OH (MeFdiEOH)) and their select transformation products, were incubated in WWTP aerobic microcosms to determine structure–activity relationships. The HFE alcohol congeners with a thioether (FESOH and MeFESOH) were observed to transform faster than the ether congeners, while also producing second‐generation HFE acid products (F7C3OCHFC(O)OH (2H‐3:2 polyfluoroalkyl ether carboxylic acid [PFECA]) and F3COCHFC(O)OH (2H‐1:2 PFECA). Subsequent biodegradation experiments with 2H‐1:2 PFESA and 2H‐1:2 PFECA displayed no further transformation over 74 days. Surface water Photofate experiments compared 2H‐1:2 PFECA, and 2H‐1:2 polyfluorinated ether sulfonate (PFESA) with their fully fluorinated ether acid counterparts, and demonstrated the potential for both HFE acid species to completely mineralize over extended periods of time, a fate that highlights the value of studying novel PFAS functionalization. Environ Toxicol Chem 2024;43:2297–2305. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Mountain meadows are ecologically important groundwater dependent ecosystems that retain and store water in upland forested landscapes. They tend to occur in low gradient, broad valleys where water slows and sediment accumulates, making them efficient locations for restoration. Over a century and a half of land use has degraded many meadows in the Sierra Nevada, reducing their hydrological and ecological functionality. Process‐based restoration (PBR) is an ecosystem rehabilitation approach that utilises biogeomorphic processes to facilitate functional ecosystem recovery. Low‐tech applications of PBR leverage fluvial processes, plant growth and the manipulation of onsite materials to increase structural and hydrological complexity. In meadows, typical goals associated with restoration are to increase groundwater elevations, expand wetted area, encourage sediment capture and create diffuse flow paths leading to improved ecological function over time. This study compares surface and groundwater conditions in a degraded riparian meadow in the Sierra Nevada, California, USA for 1 year before and after process‐based restoration to understand initial changes in meadow hydrogeomorphic function. Restoration included the installation of 39 postless beaver dam analog structures in ~1 km of incised meadow channel. Stage‐discharge data at the inlet and outlet of the project area were paired with groundwater data collected from 13 wells distributed across the meadow to estimate increased water storage of 3700 m3 due to restoration. After the wet winter of 2023, we estimated that pools upstream of structures filled to over half their volume with fine sediment. We also applied hydrodynamic modelling to evaluate fluvial changes at high flows and found that restoration increased flow complexity and wetted surface area. These short‐term responses highlight the potential speed and ability of low‐tech, process‐based restoration in achieving restoration outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water quality monitoring is paramount in identifying and mitigating pollution sources, protecting aquatic ecosystems, and ensuring safe water for human and wildlife consumption. This study is aimed at evaluating the quality of drinking water sources in three communities located in a Sustainable Use Conservation Unit in the municipality of Mangaratiba, Rio de Janeiro, Brazil, employing a multivariate statistical analysis. A total of 161 water samples were collected from January to December 2022, encompassing 32 surface water and 129 tap water samples. Physicochemical parameters were determined in situ employing a Horiba U50 multiparameter probe. The samples were stored and transported at 4 °C to the laboratory for microbiological analyses concerning total coliforms and Escherichia coli using a commercial enzymatic test. All samples contained coliforms, while E. coli were detected in 87% of the samples. The multivariate analysis indicated that the microbiological water quality in sampling region R2 was influenced by rainy periods and that, in general, the water quality within R3 was the most affected by the transport of solids to the water sources. The statistical methods applied herein aided in characterizing the study areas and detecting points of attention regarding physicochemical and microbiological parameters that significantly influence the water quality of each sampling point. Representative points for each study region were identified and may be employed for future monitoring and prevention actions. [ABSTRACT FROM AUTHOR]

Estimates of ambient background concentrations in surface waters, referred to as natural background concentrations (NBCs) in European guidance documents, may be an important factor in determining whether a monitoring site meets the legally binding Environmental Quality Standard (EQS) when assessing naturally occurring substances. Here, we focus on utilizing routine regulatory surface water monitoring data to provide risk assessors and environmental practitioners with a transparent, implementable, repeatable, and resource‐effective approach to estimate NBCs. The methodology does not use additional environmental sampling beyond that which is routine or require advanced statistical methods, or the incorporation of highly specialist, and not always readily accessible, local knowledge. It determines both whether a site is suitable for NBC assessment as well as the identification of suitable surrogate sites and local NBCs using 11 criteria: six for identifying if a site is suitable for NBC correction, and five for identifying suitable surrogate sites for local NBC values. The criteria consider both the extent of any EQS exceedance, after accounting for bioavailability in line with the European guidance and potential anthropogenic impacts at the site, and can be applied in a simple sequential procedure. The method has been applied to derive NBCs for nickel on three case‐study countries—Cyprus, France, and Spain—to determine its useability and impact on compliance. The methodology presented addresses a gap in the current guidance regarding the practical and consistent implementation of NBCs and could be applied to other naturally occurring substances in an EQS or Water Quality Guideline compliance assessment process. Integr Environ Assess Manag 2024;20:2128–2141. © 2024 WCA Environment Ltd and NiPERA Inc. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: A methodology is presented utilizing routine regulatory surface water monitoring data to provide risk assessors and environmental practitioners with a transparent, implementable, repeatable, and resource‐effective approach to estimate natural background concentrations (NBCs).The methodology determines both whether a site is suitable for NBC assessment as well as the identification of suitable surrogate sites and local NBCs using 11 criteria: six for identifying if a site is suitable for NBC correction, and five for identifying suitable surrogate sites for local NBC values.The method has been applied to derive NBCs for nickel on three case‐study countries—Cyprus, France, and Spain—to determine its useability and impact on compliance. [ABSTRACT FROM AUTHOR]

Microplastic concentrations were studied in surface waters of two reservoirs playing an important role in water storage and supply in Vietnam, the Dau Tieng and Tri An reservoirs, by collecting water samples during dry and rainy seasons. Microplastic mean concentration (including all sites and seasons per reservoir) was of 3.96 ± 1.38 items m−3 at Dau Tieng and 4.04 ± 1.35 items m−3 at Tri An, and is in the range of concentrations found in other reservoirs studied worldwide. We noted that microplastic spatial distribution was driven by difference levels of anthropogenic activities and population density surrounding each area of the reservoirs. Between the two seasons, microplastic mean abundance did not change at the level of the Dau Tieng reservoir (4.36 ± 1.71 items m−3 and 3.57 ± 0.95 items m−3 during dry and rainy season, respectively), but their value significantly decreased at specific sites under intense anthropogenic activities during the rainy season. Meanwhile, in Tri An reservoir, mean microplastic abundance and size significantly decrease during the rainy season. Although the mean abundances are low value, ecological concern needs to be addressed because of the important touristic activities and their potential impact to the quality of the water and to the agriculture development of the surrounding areas. We therefore questioned microplastic as a new parameter to include into local environmental monitoring network, and we recommended to consider microplastic as an important parameter in the monitoring control of the surface water quality of the two reservoirs. [ABSTRACT FROM AUTHOR]

This review investigates the pervasive issue of dye effluent pollution in African surface waters, focusing on its significant adverse effects on both human health and environmental quality. Drawing from 63 articles published between 2004 and 2022, the review includes studies from Northern, Western, Eastern, Central, and Southern Africa, illustrating the widespread nature of dye contamination across the continent. Five primary sources of dye effluents are identified: textiles, food industries, dye producers, artisan dyes, and tannery-paint industries, all of which contribute substantially to the degradation of water quality. The physicochemical properties of dye effluents show high toxicity levels in surface waters, with significant regional variations. These variations highlight the importance of considering the specific characteristics of dye types and processing chemicals to fully understand the contamination levels. In evaluating treatment methods, the review finds that adsorption, coagulation/flocculation, filtration, and advanced oxidation processes (AOPs) such as photocatalysis, photo-Fenton oxidation, and plasma-chemical treatment are effective in mitigating dye pollution. The application of these methods varies across different African regions, indicating the need for region-specific approaches based on local conditions and available resources. The review also examines the impact of dye effluents on aquatic ecosystems and human health, with risk assessments revealing effects ranging from acute to chronic. This demonstrates the urgent need for targeted interventions to address dye effluent pollution in African surface waters, thereby protecting both environmental and public health. Highlights: Dye effluent pollution severely impacts human health and the environment, particularly in African surface waters. Six key industries contribute to dye pollution in Africa: textile, food, pharmaceutical, tannery, paint, and artisanal. Effective treatment methods like adsorption, filtration, and AOPs show promise but require larger-scale implementation [ABSTRACT FROM AUTHOR]

Satellite rainfall estimates are robust alternatives to gauge precipitation, especially in Africa, where several watersheds and regional water basins are poorly gauged or ungauged. In this study, six satellite precipitation products, the Climate Hazards Group Infrared Precipitation with Stations (CHIRPS); Tropical Applications of Meteorology Using Satellite and Ground-based Observations (TAMSAT); TRMM Multi-satellite Precipitation Analysis (TMPA); and the National Aeronautics and Space Administration's new Integrated Multi-SatellitE Retrievals for Global Precipitation Measurement (GPM) early run (IMERG-ER), late run (IMERG-LR), and final run (IMERG-FR), were used to force a gauge-calibrated Soil & Water Assessment Tool (SWAT) model for the Congo River Basin, Central Africa. In this study, the National Centers for Environmental Prediction's Climate Forecast System Reanalysis (CFSR) calibrated version of the SWAT was used as the benchmark/reference, while scenario versions were created as configurations using each satellite product identified above. CFSR was used as an independent sample to prevent bias toward any of the satellite products. The calibrated CFSR model captured and reproduced the hydrology (timing, peak flow, and seasonality) of this basin using the average monthly discharge from January 1984–December 1991. Furthermore, the results show that TMPA, IMERG-FR, and CHIRPS captured the peak flows and correctly reproduced the seasonality and timing of the monthly discharges (January 2007–December 2010). In contrast, TAMSAT, IMERG-ER, and IMERG-LR overestimated the peak flows. These results show that some of these precipitation products must be bias-corrected before being used for practical applications. The results of this study will be significant in integrated water resource management in the Congo River Basin and other regional river basins in Africa. Most importantly, the results obtained from this study have been hosted in a repository for free access to all interested in hydrology and water resource management in Africa. [ABSTRACT FROM AUTHOR]

Hydrologic models are the primary tools that are used to simulate streamflow drought and assess impacts. However, there is little consensus about how to evaluate the performance of these models, especially as hydrologic modeling moves toward larger spatial domains. This paper presents a comprehensive multi-objective approach to systematically evaluating the critical features in streamflow drought simulations performed by two widely used hydrological models. The evaluation approach captures how well a model classifies observed periods of drought and non-drought, quantifies error components during periods of drought, and assesses the models' simulations of drought severity, duration, and intensity. We apply this approach at 4662 U.S. Geological Survey streamflow gages covering a wide range of hydrologic conditions across the conterminous U.S. from 1985 to 2016 to evaluate streamflow drought using two national-scale hydrologic models: the National Water Model (NWM) and the National Hydrologic Model (NHM); therefore, a benchmark against which to evaluate additional models is provided. Using this approach, we find that generally the NWM better simulates the timing of flows during drought, while the NHM better simulates the magnitude of flows during drought. Both models performed better in wetter eastern regions than in drier western regions. Finally, each model showed increased error when simulating the most severe drought events. [ABSTRACT FROM AUTHOR]

Arizona has a long history of groundwater use, and there is concern about long term groundwater sustainability across the state. We explore groundwater trends across Arizona and how they vary with respect to: (1) whether groundwater pumping is regulated, and (2) relative access to local or imported surface water. Well observations from the Arizona Department of Water Resources are used to quantify water table depth trends and groundwater drilling patterns. There are more than 85,000 groundwater wells in Arizona, and new wells are routinely being drilled. The number of new shallow wells (<200 ft) has decreased over time in all parts of the state. But midrange (200–500 ft) to deep (>500 ft) wells have increased in the past 10 years in regulated and groundwater dominated areas. Most wells are small with low pumping capacities that fall below the regulatory limit; however, there are still large wells being drilled in unregulated areas. Results show statewide decreasing water storage and groundwater levels. Groundwater declines are less severe in the parts of the state that have groundwater regulation. However, looking closer at this trend, groundwater recovery is strongest in areas receiving imported Colorado River water which also implement managed groundwater recharge with the imported water. Our findings indicate that groundwater recovery is very localized and driven more by managed recharge from surface water as opposed to decreased groundwater pumping. [ABSTRACT FROM AUTHOR]

The presence of polycyclic hydrocarbons (PAHs) and microplastics (MPs) in aquatic environments affects the ecosystems and threatens human health. In this study, the abundance, composition, and morphological characteristics of MPs were determined for the first time in the inland freshwater resources of the Konya Closed Basin, Turkey. The abundance of MPs ranged from 1139 to 23,444 particles/m3 and 150 to 3510 particles/kg in the surface water and sediment, respectively. Fragments and fibers were the most abundant MP shapes in the surface waters (51%, 34%) and sediments (29%, 40%), followed by films, pellets, and foams. Transparent and white MPs were present at the highest percentage in surface waters (72%) and sediments (69%), followed by blue, grey, black, brown, and green. In addition, polyethylene, polypropylene, and cellophane were identified as the main polymers in surface waters (34%, 25%, 24%) and sediments (37%, 17%, 31%). In the Konya Closed Basin, 35% of the surface water samples and 54% of the sediment samples were exposed to very high contamination (CF ≥ 6). Surface waters (PLI: 2.51) and sediments (PLI: 1.67) in the basin were contaminated (PLI > 1) with MPs. The 16 PAHs sorbed on MPs in the surface water and sediment ranged from 394 to 24,754 ng/g and from 37 to 18,323 ng/g, respectively. Phenanthrene and fluoranthene were the most abundant PAHs sorbed on MPs in all surface waters and sediments. Two to three-ring PAH compounds sorbed on MPs were also dominantly detected in surface waters and sediments, accounting for 68% and 78% of the total 16 PAHs, respectively. The source of PAHs carried by MPs in the Konya Closed Basin was mainly of petrogenic origin. Incremental lifetime cancer risk (ILCR) results indicated that the maximum ILCR values were higher than the EPA acceptable level (10−6) for child (2.95 × 10−5) and adult (1.46 × 10−4), indicating a potential cancer risk. [ABSTRACT FROM AUTHOR]

Recreational water activities have become an integral part of society for entertainment, health, and fitness. The water quality for these activities plays an integral role in the health and safety of the participants. This study aimed to monitor the presence of Escherichia coli in selected recreational water bodies, specifically rowing in the Gauteng Province of South Africa. Water samples were collected (upstream, midstream, and downstream) from three recreational water sites, i.e., Klip Rivier, Wemmer Pan, and Germiston Lake, monthly from May to October 2022. The presence of E. coli was determined using the Colilert® Quanti-Tray®/2,000 (IDEXX) assay and Chromo Select agar. Pathotypes were confirmed using a multiplex PCR. The MPN for E. coli from all the samples exceeded the recommended guidelines of,2,000 microbes/100 mL. Pathogenic E. coli was detected in all three sites, with EPEC, ETEC, EAEC being most prevalent. The E. coli isolates showed 66% ESBL resistance and 94% carbapenemase resistance. Risk assessment showed recreational activities (rowing and swimming) posed a significant health risk as exceeded the annual risk benchmark limit of 1x104 . The results obtained provide insights into the health risk associated with recreational activities within these water bodies and highlight the need for seasonal monitoring. [ABSTRACT FROM AUTHOR]

The increasing global reliance on pesticides for agricultural pest control has raised significant environmental concerns, particularly due to inadequate monitoring of emerging chemicals in surface waters. This study addresses the potential contamination of aquatic ecosystems by developing and validating a method for detecting trace amounts of four recently registered fungicides: three succinate dehydrogenase inhibitors (fluopyram, penthiopyrad, pydiflumetofen) and fluopicolide, a structurally related fungicide. Employing QuEChERS-based sample extraction combined with ultra-high-performance liquid chromatography (UHPLC-MS-MS), this method achieves detection limits of 0.1 to 0.2 μg/L, with recovery rates between 90% and 110%, and intra-day relative standard deviation values well within the acceptable range of less than 20%. Applied to surface grab water samples from the greater Melbourne area, Australia, the method successfully identified all four fungicides at trace levels, including a notable high concentration of fluopyram (7.3 μg/L) during autumn, with the others intermittently detected at lower concentrations. This study represents the first documented instance of quantifiable detections of these four fungicides in Australian surface water systems. Given their high toxicity to several organisms and the limited global data on these substances, our findings underscore the critical need for continuous monitoring to inform strategies to safeguard aquatic ecosystems from these chemicals. [ABSTRACT FROM AUTHOR]

Water classification in Synthetic Aperture Radar (SAR) images is an ongoing area of research, which has implications in environmental monitoring and water resource management. Adaptive threshold algorithms provide a fast, reliable and efficient way to perform automated water classification, but users often lack awareness on selecting the best algorithm for their specific application. This paper presents a comprehensive assessment of adaptive threshold algorithms for water delineation applied to L- and C-band SAR backscatter images. We introduce a novel approach for dynamic selection of windows within a SAR image to determine optimum thresholds on sigma naught values. A comparison of five threshold-determination techniques is performed which include Otsu, Kittler and Illingworth (KI), Gaussian Mixture Model (GMM), Quality Index (QI) and Gamma Maximum Likelihood Estimation (GMLE) algorithms. We observed that, for L-band SAR data, convex hull approach produced better kappa coefficient value with GMM, KI and GMLE algorithms. However, for C-band SAR, kappa coefficients were highest for convex hull method with GMM, KI, QI and GMLE approaches and noticeably higher (> 0.89) when compared to split window approach. Our analysis indicates that the proposed convex hull method for window selection performs better in both L- and C-band SAR images. The results of our analysis will help users in identifying the best adaptive algorithm for water delineation in L- and C-band SAR images. [ABSTRACT FROM AUTHOR]

The tritium content in the surface water of the Suifen River in China was measured using an ultra low-level liquid scintillation spectrometer. In August and October, a total of 30 samples were collected (15 per month) The measured 3H activity concentration ranged from 5.08 to 9.75 Bq L−1, and the annual effective dose ranged from 0.07 to 0.13 μSv. These values are below WHO's recommendations, indicating no risk to human health. Although the 3H activity concentration was higher in October than in August, statistical analysis did not show a significant difference between the two months. [ABSTRACT FROM AUTHOR]

It is necessary to analyze the characteristics of the water environment and factors influencing the basin in order to determine its current ecological status. This study aims to investigate the chemical properties in the Shichuan River Basin using Gibbs diagram, Piper triangle diagram, correlation analysis, factor analysis, and main ion ratio method. The enhanced Nemerow comprehensive index method and fuzzy comprehensive evaluation method are employed for river water quality assessment. The findings reveal that runoff water has a weak alkaline nature with low salinity. The hydrochemical type of river water includes Ca2++Mg2++Na+-SO42-, Ca2++Mg2+-SO42-+Cl-+HCO3-, Ca2++Na+-SO42-+Cl-+HCO3-. Silicite and dolomite weathering are identified as primary influencing factors, while evaporite weathering also contributes to variations in chemical composition within the basin's waters. Ca2+, Mg2+, SO42- and HCO3- originate from carbonate rock and silicate rock weathering processes, whereas Na+, K+ and Cl-, are primarily derived from evaporite weathering influenced by domestic sewage and agricultural activities. Agricultural production practices along with discharge of domestic sewage have an impact on Na+, K+, Cl- and NO3-concentrations in aquatic systems. Water quality at all three monitoring sections falls under level IV classification. Phosphorus emerges as a key limiting factor for eutrophication within this basin's watersheds. [ABSTRACT FROM AUTHOR]

There are many reservoirs, ponds and Korotoa River in the capital of ancient Pundranagar, Bangladesh, which is an intensive agricultural region. Since different industries are operated for the preparation of different agricultural instruments and agrochemicals are extensively applied to the agricultural soils which mix with the river and pond water and these water bodies may be contaminated with trace elements. In this study, levels of nine trace elements (Cr, As, Cu, Ni, Zn, Cd, Fe, Mn and Pb) and physicochemical properties in surface water from one river and five ponds were measured and compared with water quality guidelines. In addition, health risks, pollution status and possible sources of trace elements were assessed. The mean concentrations of As, Cd, Pb, Cr, Ni, Cu, Fe, Mn and Zn in pond water were 0.059, 0.033, 0.067, 0.136, 0.133, 0.280, 0.733, 0.127 and 0.266 mg/L and river water were 0.055, 0.037, 0.054, 0.104, 0.120, 0.230, 0.702, 0.125 and 0.200 mg/L, respectively. Except Cu and Zn, the mean concentrations of trace elements were above the water quality permissible standards indicating water from these sources is not safe for human use. The WQI values suggested that the water quality is excellent to poor water quality class. Health risk indices indicated that As in water via ingestion exposure pathway may pose both non-carcinogenic and carcinogenic health risks to the residents where the non-carcinogenic risk to the residents is raised from ingestion of As, Cd, Cr and Pb from water. [ABSTRACT FROM AUTHOR]

In the scientific research work, the process of neutralization and cleaning of microorganisms harmful to human health found in surface water with an ozonator device based on a pilot electric discharge is considered. A pilot ozonator based on a special high-frequency electric discharge has been developed for disinfection and cleaning of harmful microorganisms found in surface water. In order to conduct practical tests on scientific research work, special water was taken from the Ili floodplain and an examination of the water composition was carried out. According to the results of the examination, various painful microorganisms were found in the composition of the source water that do not meet the maximum permissible concentration (MPC). Effective economic indicators of ozone content (mg/l), contact time (t, minutes) and the like were determined for disinfection and removal of microorganisms from the water composition. In addition, an algorithm for theoretical calculations for the destruction of harmful microorganisms in 1m³ surface water was compiled and a mathematical model was given. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study deals with the assessment of different physicochemical parameters (pH, electrical conductivity (E.C.), turbidity, total dissolved solids (TDS), and dissolved oxygen) in different surface water such as pond, river, and canal water in four different seasons, viz. March, June, September, and December 2023. The research endeavors to assess the impact of a cationic polyelectrolyte, specifically poly(diallyl dimethyl ammonium chloride) (PDADMAC), utilized as a coagulation aid in conjunction with lime for water treatment. Employing a conventional jar test apparatus, turbidity removal from diverse water samples is examined. Furthermore, the samples undergo characterization utilizing X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The study also conducts correlation analyses on various parameters such as electrical conductivity (EC), pH, total dissolved solids (TDS), turbidity of raw water, polyelectrolyte dosage, and percentage of turbidity removal across different water sources. Utilizing the Statistical Package for Social Science (SPSS) software, these analyses aim to establish robust relationships among initial turbidity, temperature, percentage of turbidity removal, dosage of coagulant aid, electrical conductivity, and total dissolved solids (TDS) in pond water, river water, and canal water. A strong positive correlation could be found between the percentage of turbidity removal and the value of initial turbidity of all surface water. However, a negative correlation could be observed between the polyelectrolyte dosage and raw water's turbidity. By elucidating these correlations, the study contributes to a deeper understanding of the effectiveness of PDADMAC and lime in water treatment processes across diverse environmental conditions. This research enhances our comprehension of surface water treatment methodologies and provides valuable insights for optimizing water treatment strategies to address the challenges posed by varying water sources and seasonal fluctuations. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are ubiquitous in the environment and may threaten the ecosystem. Currently, research on MP pollution in China has focused on urban and coastal areas. To better understand the extent of MP pollution in the surface water of rural areas, we investigated the abundance, particle size, color, shape, and polymer chemical characteristics of MPs in the Longjiang River in China during the wet season (August) and dry season (December). The results showed that MPs were detected at all 12 sampling sites in August and December, with higher mean abundances observed in August (112.60 ± 5.63 items/m3) than in December (49.34 ± 2.47 items/m3). The predominant particle sizes of the MPs ranged from 100–500 µm, transparent was the most common appearance, and debris was the most common shape. Chemical characterization revealed that polyethylene (PE) and polyvinyl chloride (PVC) were the major polymer types. Correlation analysis indicated that agricultural film usage was the primary source of MP pollution in the Longjiang River basin. Risk assessments were conducted based on the chemical characteristics and abundances of MPs, revealing a high risk level due to the presence of hazardous PVC. However, the overall potential ecological level of MP pollution in the Longjiang River basin was lower than that observed in urban areas due to the lower abundances and pollution loads. This study provides valuable baseline data to assess the environmental risks associated with MPs and serves as a basis to formulate effective environmental policies. [ABSTRACT FROM AUTHOR]

The Ngari region has many important rivers and is critical to water resource security and water resource continuity in China and even in adjoining Asian countries. However, the spatial distribution and monthly variation in local water quality have been poorly understood until recently. In this study, the spatial–temporal variations of 12 water quality parameters, including pH, dissolved oxygen (DO), permanganate index (IMn), chemical oxygen demand (COD), five-day biochemical oxygen demand (BOD5), ammonia nitrogen (NNH3), total nitrogen (Ntotal), total phosphorus (Ptotal), copper (Cu), fluoride (F), arsenic (As) and cadmium (Cd), were determined from samples collected monthly at 22 water cross-sectional sites in the Ngari region in 2020. The surface water pollution in the southern Ngari region was the most serious, and the water pollution level in winter was higher than that in the other seasons. As (0.0781 ~ 0.6154 mg/L) and F (1.05 ~ 4.64 mg/L) were the main exceedance factors derived from the recharge of high arsenic and fluoride geothermal water and weathering of As and F-bearing minerals. The hazard quotient and carcinogenic risk for As and F at the five contaminated sampling sites indicated potential health risks and even carcinogenicity to local populations. The hydrochemistry types of the lakes and rivers in the Ngari region were mainly chloride water and carbonate water. The results from this study can provide a scientific basis for the prevention and control of surface water pollution in the Ngari region and contribute to subsequent research on the ecology of water bodies. [ABSTRACT FROM AUTHOR]

Climate change and its variability impact water availability in wetlands, jeopardizing their ecosystems. This study focuses on the Sudd Wetland, Africa’s most extensive and one of the world’s largest tropical wetland systems. We analyzed historical climate data (temperature, rainfall) in the Sudd and its upstream regions to assess climate impacts on the wetland’s health (NDVI) and water conditions (surface water extent, lake height) using spatial and temporal trends. The study unveils distinct seasonal and long-term variations in vegetation and temporal fluctuations in surface water dynamics within the Sudd Wetland. While central areas experienced declining NDVI (vegetation cover), peripheries showed an increase. The wetland gained open water surface area, with a slight rise in permanent water (3%) and a significant increase in seasonal inundations (19%). All monitored water bodies in the Sudd displayed a gradual increase in surface water height. Climate shifts are observed as rising temperatures and increased rainfall trends. Annual and seasonal temperatures rose across the basin, with the January-Feburary season experiencing the most significant increase (~ 1.3 °C). Rainfall trends were mostly flat, except for the south-central and southeastern regions, where a statistically significant increase ranging from 5 mm to 17 mm per year was observed. Conclusive evidence from this paper could be used to assess water policy and management in the region while protecting key parts of the hydrologic cycle. [ABSTRACT FROM AUTHOR]

Considering the diverse landscape of rainfall-runoff models, a thorough evaluation of their capabilities and limitations is essential for the selection of an optimal model. This study aims to assess the performance of rainfall-runoff hydrological models in the Malayer watershed. In this study, Rainfall-runoff simulation was carried out using SWAT and IHACRES models and meteorological data from 2005 to 2020. The calibration and validation of the model were done using the SUFI-2 algorithm. The results of sensitivity analysis showed that the melting factor, hydraulic conductivity of soil saturation, and snowfall temperature are the most important parameters controlling the flow rate in the study area. The R2 and NS coefficients for SWAT were calculated as 0.68 and 0.65 in the calibration period and 0.63 and 0.70 in the validation period, respectively which in these results showed the SWAT model has suitable efficiency for estimating the watershed flow. Based on the simulation results of the IHACRES model, the values ​​of R2 and NS are 0.66 and 0.58 in the calibration period and 0.52 and 0.51 in the validation period, respectively. Considering that the IHACRES model simulates runoff on a daily scale, the efficiency of the model can be evaluated as acceptable.

Although the removal of colloidal particles continues to be an important reason for using coagulation, currently a newer approach, the removal of organic matter to reduce the formation of disinfection byproducts (DBPs) such as trihalomethanes (THMs) are suspected carcinogens. Inefficient removal of total organic carbon (TOC) leads to the formation of carcinogenic THMs. This motivates the research efforts to find a way to reduce them in potable water. The first objective of this research is monitoring the water quality (raw and produced) for selected three water treatment plants within Giza Governorate to reveal the most polluted site (high TOC in the raw water and THMs in the treated water) in the study areas. The second objective of this study is enhancing coagulation to reduce TOC and THMs from surface water treating. In this study, two different coagulants aluminum sulfate (alum), and ferric chloride were tested under different conditions of pH and coagulant concentration to determine their effectiveness for removal of TOC, THMs and turbidity. Optimum values for the mentioned conditions were used to achieve the maximum reduction for TOC and THMs in Al-Ayat drinking water treatment plant (DWTP) which recorded the highest concentration of TOC and THMs. Ferric chloride as a coagulant achieved the maximum removal percentage % of TOC, THMs and turbidity as 79%, 82% and 94%, respectively, at ferric chloride dose 100 mg/L, while alum as a coagulant recorded the maximum removal percentage % of TOC, THMs and turbidity as 46%, 52% and 91%, respectively, at alum dose 100 mg/L. The results indicated that ferric chloride as a coagulant has the highest efficiency reduction of TOC, THMs and turbidity if compared to alum with the same dose added.

Abstract An integrated approach using geophysical and geospatial techniques was employed to model the surface and subsurface water-bearing strata and assess aquifer vulnerability in the Sehnsa town, Kotli district, State of Azad Kashmir, Pakistan. The inadequate scientific studies in the hilly terrain with such complex geological conditions has led to the failure of the boreholes for groundwater extraction. For the evaluation of groundwater potential and subsurface lithology, 30 vertical electrical soundings (VES) stations utilizing the Schlumberger electrode configuration were completed, modeled and analyzed spatially. Numerous geoelectrical parameters like true resistivity, thickness of subsurface layers and Dar-Zarrouk parameters were evaluated. The subsurface lithology delineated comprised topsoil, clayey sand, sandstone, and boulder clays which closely resemble to the borehole lithologs available in the study area. The inversion model confirms the presence of patches of high-resistivity sandstone in the southwestern part of the study area with the maximum thickness of the aquifer up to 140 m. Most aquifers were classified as unconfined with Q–type resistivity curves. The protective overburden capacity of the aquifers is rated as poor at VES 1, 3–5, 8, 10–16, 18, 19, 22–25, 27 and 30 whereas the moderate category was found at VES 2, 9 and 20 and excellent at VES 7 and 28, respectively. Therefore, the VES stations with poor and moderate ratings of overburden protective capacity are vulnerable for surface contaminants. The aquifer recharge was associated with rainfall and partly from the Poonch River. The effective integration of geophysical and geospatial techniques in this study provides sufficient information about the regional water resources and gives a preliminary model that can facilitate efficient water resource management in the area. These approaches can be successfully applied to diverse geographical and hydrogeological sites due to their versatility and reliability.

The study was conducted to determine the suitability of surface water from Oued El Gourzi for irrigation in the Fesdis area, Algeria, during irrigation season of July 2022. The suitability was assessed by analysing eight water samples collected from various sites along the Oued. A range of physicochemical parameters were examined, including EC, pH, Mg2+, Na+, Ca2+, K+, HCO3– and Cl–, alongside other indices such as sodium absorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), permeability index (PI) and magnesium adsorption ratio (MAR) using standard procedures. The Richards classification shows that these waters are characterised by high salinity and low alkalinity hazard (C3–S1). According to the Wilcox classification, the majority of these waters are of doubtful quality, with only 25% exhibiting good quality for irrigation. Based on the RSC and MAR, all water samples are deemed safe and suitable for irrigation. However, PI values suggest that all sampling sites are of marginal quality for irrigation (class II). In terms of sodium and chloride concentration, all water samples were deemed unsuitable for irrigation. Based on these results, the waters pose risks for irrigation, particularly due to salinity, necessitating the implementation of special management practices and the selection of salt-tolerant crops.

Abstract This review investigates the pervasive issue of dye effluent pollution in African surface waters, focusing on its significant adverse effects on both human health and environmental quality. Drawing from 63 articles published between 2004 and 2022, the review includes studies from Northern, Western, Eastern, Central, and Southern Africa, illustrating the widespread nature of dye contamination across the continent. Five primary sources of dye effluents are identified: textiles, food industries, dye producers, artisan dyes, and tannery-paint industries, all of which contribute substantially to the degradation of water quality. The physicochemical properties of dye effluents show high toxicity levels in surface waters, with significant regional variations. These variations highlight the importance of considering the specific characteristics of dye types and processing chemicals to fully understand the contamination levels. In evaluating treatment methods, the review finds that adsorption, coagulation/flocculation, filtration, and advanced oxidation processes (AOPs) such as photocatalysis, photo-Fenton oxidation, and plasma-chemical treatment are effective in mitigating dye pollution. The application of these methods varies across different African regions, indicating the need for region-specific approaches based on local conditions and available resources. The review also examines the impact of dye effluents on aquatic ecosystems and human health, with risk assessments revealing effects ranging from acute to chronic. This demonstrates the urgent need for targeted interventions to address dye effluent pollution in African surface waters, thereby protecting both environmental and public health. Graphical Abstract

• PAEs in water from the Three Gorges Reservoir area were investigated. • PAEs polluted the upper reaches of the Yangtze River more than the middle reaches. • Molecular weight and log K ow significantly affected the input and losses of PAEs. • DnNP may cause potential adverse effects for the aquatic ecology. Phthalic acid esters (PAEs) are a group of compounds widespread in the environment. To investigate the occurrence and accumulation characteristics of PAEs, surface water samples were collected from the Three Gorges Reservoir area, China. The total concentrations of 11 analyzed PAEs (∑ 11 PAEs) in the collected water samples ranging from 197.7 to 1,409.3 ng/L (mean ± IQR: 583.1 ± 308.4 ng/L). While DEHP was the most frequently detected PAE, DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3% of the ∑ 11 PAEs. The concentrations of the ∑ 11 PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from the middle reaches. To better understand the transport and fate of the PAEs, seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction (QWASI). The simulated and measured values were close for most PAEs, and differences are within one order of magnitude even for the worst one. For all simulated PAEs, water and particle inflow were main sources in the reservoir, whereas water outflow and degradation in water were important removal pathways. The contribution ratios of different sources/losses varied from PAEs, depending on their properties. The calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based on monitoring or simulating results were all far exceeded the safety threshold value, implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Pesticides in surface freshwater primarily originate from their emissions in agricultural lands, potentially leading to violations of surface freshwater quality standards. To aid global regulatory agencies in effectively managing surface freshwater quality by estimating and controlling pesticide emission rates, this study proposes a hierarchical screening approach for countries and regions worldwide to select appropriate modeling tools. Hierarchical indicators are introduced to classify countries globally, considering their spatial distribution areas, pesticide emission conditions, and legislative systems. Consequently, different categories of countries are matched with suitable model groups, such as the standard model group for regulatory scenarios, the general model group for continental scenarios, and the advanced model group with high spatial resolution. Results indicated that a total of 193 countries worldwide were categorized into six country groups, of which 153, 34, and 6 countries were found to fit the standard, general, and advanced model groups, respectively, based on the model assignments for these country groups. Furthermore, 12 commonly used pesticides were selected to demonstrate the back-calculation process, which estimates the pesticide emission rate (input) by pesticide surface freshwater quality standards (output) by standard and general model groups. The Advanced model group was not applied in this process due to its intensive computation. An approximate approach was developed to simplify the calculation of the emission rate factor of pesticides using the PWC and TOXSWA selected in the standard model group as well as SWAT in the general model group, serving as a demonstration. This approach can be applied to control pesticide emission rates from surface freshwater quality standards across countries that fit in the standard and general model groups. The results highlight that pesticide fate models selected through the hierarchical screening approach, can assist global countries in establishing a quantitative relationship between pesticide emission rates and surface freshwater quality standards, which can help global agencies manage pesticide emissions and freshwater quality from a legal perspective. There is a need to update and simplify suitable advanced model for calculation demonstration in future studies to aid in pesticide management. Further research is needed to thoroughly investigate pesticide emissions and freshwater residue concentrations under varying conditions.

In Southern Nigeria, there is the problem of inadequate access to safe drinking water and the incidence of water-borne diseases that reduce vitality and economic productivity. It is on this premise that the paper assesses the upshots of surface water quality on the wide range of water-borne disease cases in the study area. The study employed an experimental and expost facto research design. A surface water sample from each of the six communities along River Ase was analyzed for physicochemical and bacteriological quality parameters using standard procedures for twelve months. The resulting data were compared to the WHO recommended limits and the suitability of the surface water for residential use was determined using the water quality index. In addition, health records of persons diagnosed and treated for water-borne diseases were collected from limited health record centers in the study communities to determine those impacted by water-borne diseases. Data were analyzed using descriptive statistics and multiple regression statistical techniques to test the posited hypothesis (Ho). The results showed that there is variation in the water quality of the river. The posited hypothesis showed that 51% of the incidence of water-borne diseases was significantly dependent on the quality of water at P > 0.05. Also, the WQI indicated that the water quality fell between bad and medium (42.80 - 58.05), indicating that the water should be treated before consumption. The study, therefore, recommends the testing of the water periodically to safeguard human health.

Abstract Dumpsites generate leachates containing bacteria that may carry antibiotic resistance genes, such as extended spectrum β-lactamase (ESBL). However, the contribution of dumpsite leachates in the environmental spread of ESBL genes has not been investigated in greater detail. This study aimed to quantify the impact of Ajakanga dumpsite leachate on the spread of ESBL genes through surface water. The susceptibility of Escherichia coli isolated from dumpsite leachate and the accompanying surface water to selected antibiotics was assessed by the standardized disc diffusion method. The isolates were evaluated for phenotypic ESBL production using the double disc synergy test (DDST). The detection of ESBL genes in the isolates was carried out using a primer-specific polymerase chain reaction (PCR). Escherichia coli isolates from leachate (n = 26/32) and surface water (n = 9/12) expressed ESBL phenotype. The ESBL-producing isolates showed the highest level of resistance to the 3rd generation cephalosporin antibiotics: cefotaxime (100%), cefpodoxime (97%), ceftazidime (97%), with low resistance observed to imipenem (6%) and azithromycin (3%). All the isolates were multidrug-resistant, showing resistance to three or more classes of antibiotics. All the ESBL-producing E. coli obtained carried bla CTX−M, 21/35 (60%) carried bla TEM while none of the isolates bore bla SHV. This study found that ESBL-producing Escherichia coli from dumpsite leachate and nearby surface water had identical resistance signatures indicating the relatedness of the isolates, and that dumpsite leachate could contribute to the transfer of ESBL-producing bacteria and their genes to receiving surface water. This study has necessitated the need for a review of the guidelines and operational procedures of dumpsites to forestall a potential public health challenge.

The consumption of fluoride below the safe limit can result in dental caries, while high concentrations can lead to fluorosis, which can potentially impair the body's systems. One geological factor that influences the concentration of fluoride in water is the type of rock through which the water passes, including granite and its weathering products. The area is located within the Tandjungbuku Formation, which is predominantly composed of granite rock and contains several areas with Mining Business Permits (IUP) for commodities such as silica sand. This research serves as a form of mitigation in response to mining activities, post-mining, and the development of an industrial area. One anticipated impact is an increase in fluoride concentration in the research area, originating from both natural geological processes and human activities. The investigation involved geological mapping, petrographic analysis, XRD, and XRF analysis. Water sampling was conducted for both surface water and groundwater from wells in Resang Tandjungbuku Village. The research area consists of two rock units: granite, which acts as a non-aquifer layer, and colluvial deposits, which function as a free aquifer. Petrographic analysis identified minerals associated with fluoride, such as plagioclase, amphibole, and biotite. This was supported by XRD analysis with the presence of biotite, muscovite and kaoline minerals. XRF results revealed fluoride values in granite rock at 0.23% or 2300 ppm, further confirming granite as a source of fluoride. Analysis of fluoride in surface water showed values ranging from 0.01 to 4.24 mg/L, while groundwater consistently had a value of 0.01 mg/L.

Pesticides in surface freshwater primarily originate from their emissions in agricultural lands, potentially leading to violations of surface freshwater quality standards. To aid global regulatory agencies in effectively managing surface freshwater quality by estimating and controlling pesticide emission rates, this study proposes a hierarchical screening approach for countries and regions worldwide to select appropriate modeling tools. Hierarchical indicators are introduced to classify countries globally, considering their spatial distribution areas, pesticide emission conditions, and legislative systems. Consequently, different categories of countries are matched with suitable model groups, such as the standard model group for regulatory scenarios, the general model group for continental scenarios, and the advanced model group with high spatial resolution. Results indicated that a total of 193 countries worldwide were categorized into six country groups, of which 153, 34, and 6 countries were found to fit the standard, general, and advanced model groups, respectively, based on the model assignments for these country groups. Furthermore, 12 commonly used pesticides were selected to demonstrate the back-calculation process, which estimates the pesticide emission rate (input) by pesticide surface freshwater quality standards (output) by standard and general model groups. The Advanced model group was not applied in this process due to its intensive computation. An approximate approach was developed to simplify the calculation of the emission rate factor of pesticides using the PWC and TOXSWA selected in the standard model group as well as SWAT in the general model group, serving as a demonstration. This approach can be applied to control pesticide emission rates from surface freshwater quality standards across countries that fit in the standard and general model groups. The results highlight that pesticide fate models selected through the hierarchical screening approach, can assist global countries in establishing a quantitative relationship between pesticide emission rates and surface freshwater quality standards, which can help global agencies manage pesticide emissions and freshwater quality from a legal perspective. There is a need to update and simplify suitable advanced model for calculation demonstration in future studies to aid in pesticide management. Further research is needed to thoroughly investigate pesticide emissions and freshwater residue concentrations under varying conditions. [ABSTRACT FROM AUTHOR]

Surface water pollution is a critical and urgent global issue that demands immediate attention. Surface water plays a crucial role in supporting and sustaining life on the earth, but unfortunately, till now, we have less understanding of its spatial and temporal dynamics of discharge and storage variations at a global level. The contamination of surface water arises from various sources, classified into point and non-point sources. Point sources are specific, identifiable origins of pollution that release pollutants directly into water bodies through pipes or channels, allowing for easier identification and management, e.g., industrial discharges, sewage treatment plants, and landfills. However, non-point sources originate from widespread activities across expansive areas and present challenges due to its diffuse nature and multiple pathways of contamination, e.g., agricultural runoff, urban storm water runoff, and atmospheric deposition. Excessive accumulation of heavy metals, persistent organic pollutants, pesticides, chlorination by-products, pharmaceutical products in surface water through different pathways threatens food quality and safety. As a result, there is an urgent need for developing and designing new tools for identifying and quantifying various environmental contaminants. In this context, chemical and biological sensors emerge as fascinating devices well-suited for various environmental applications. Numerous chemical and biological sensors, encompassing electrochemical, magnetic, microfluidic, and biosensors, have recently been invented by hydrological scientists for the detection of water pollutants. Furthermore, surface water contaminants are monitored through different sensors, proving their harmful effects on human health. [ABSTRACT FROM AUTHOR]

The extensive use of pesticides has led to the contamination of natural resources, sometimes causing significant and irreversible damage to the environment and human health. Even though the use of many pesticides is banned, these compounds are still being found in rivers worldwide. In this review, 205 documents have been selected to provide an overview of pesticide contamination in rivers over the last 10 years (2014–2024). After these documents were examined, information of 47 river systems was organized according to the types of pesticides most frequently detected, including organochloride, organophosphorus, and pyrethroid compounds. A total of 156 compounds were classified, showing that 46% of these rivers contain organochlorine compounds, while 40% exhibit organophosphorus pesticides. Aldrin, hexachlorocyclohexane, and endosulfan were the predominant organochlorine pesticides with concentration values between 0.4 and 37 × 105 ng L−1. Chlorpyrifos, malathion, and diazinon were the main organophosphorus pesticides with concentrations between 1 and 11 × 105 ng L−1. Comparing the pesticide concentrations with standard guidelines, we found that the Ganga River in India (90 ng L−1), the Owan and Okura Rivers in Nigeria (210 and 9 × 103 ng L−1), and the Dong Nai River in Vietnam (68 ng L−1) exceed the permissible levels of aldrin (30 ng L−1). [ABSTRACT FROM AUTHOR]

Increasing water withdrawals and changes in land cover/use are critically altering surface water bodies, often causing a noticeable reduction in their area. Such anthropogenic modification of surface waters needs to be thoroughly examined to recognize the dynamics through which humans affect the loss of surface water. By leveraging remotely-sensed data and employing a distance–decay model, we investigate the loss of surface water resources that occurred in Italy between 1984 and 2021 and explore its association with land cover change and potential human pressure. In particular, we first estimate the land cover conversion across locations experiencing surface water loss. Next, we identify and analytically model the influence of irrigated and built-up areas, which heavily rely on surface waters, on the spatial distribution of surface water losses across river basin districts and river basins in Italy. Our results reveal that surface water losses are mainly located in northern Italy, where they have been primarily replaced by cropland and vegetation. As expected, we find that surface water losses tend to be more concentrated in the proximity of both irrigated and built-up areas yet showing differences in their spatial occurrence and extent. These observed spatial patterns are well captured by our analytical model, which outlines the predominant role of irrigated areas, mainly across northern Italy and Sicily, and more dominant effects of built-up areas across the Apennines and in Sardinia. By highlighting land cover patterns following the loss of surface water and evaluating the relative distribution of surface water losses with respect to areas of human pressure, our analysis provides key information that could support water management and prevent future conditions of water scarcity due to unsustainable water exploitation. [ABSTRACT FROM AUTHOR]

The Nile River is one of the longest rivers in the world, serving as the lifeline of many countries. The river is subjected to significant anthropogenic pressures, and thus, understanding the magnitude of contamination and its possible consequences is needed. This research aimed to evaluate the presence of heavy metals in the surface water of an understudied region within the Nile River. The distribution and level of 18 elements along the Damietta branch were assessed, and their potential sources were estimated. Additionally, pollution indices and health risks were calculated. The results showed that most metals were within the acceptable levels of USEPA and WHO. However, Na, Mg, and Ca were higher than the permissible level of WHO, and K was higher than the permissible levels for irrigation. Furthermore, heavy metal pollution indicators, degree of contamination indices, heavy metal evaluation indices, Nemerow pollution indices, and water quality indices all pointed to very high standards for water quality. Also, the noncarcinogenic health risk index indicated a safe limit for dermal and oral exposure for adults and children. Overall, this study recommends management focus on anthropogenic activities in the Damietta branch of the Nile River. [ABSTRACT FROM AUTHOR]