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This work describes a novel technique for the measurement of inorganic arsenic in water by generating arsine gas and detecting the conductivity of moving protons, H+ (aqueous or aq), produced by the reaction: Ag+ (aq) + AsH3 (gas, g) → AgAsH2 (solid, s) + H+ (aq). The detection is based on an electrochemical gradient of protons in a confined porous substrate (filter paper) and measures the change in the conductance due to the higher mobility of H+ compared to other ions. The conductance was measured with a pair of silver electrodes attached to opposite sides of the substrate with a bipolar pulse conductance technique. The method is established in theory and in practice. The theoretical equation for conductance change shows that a constant increase in conductance is directly proportional to the As(total) concentration. The method is validated with a standard reference material and applied to the measurement of the groundwater sample. [ABSTRACT FROM AUTHOR]

This study used integrated geochemical, and ionic ratios, to investigate hydrogeochemical aspects, quality, and possible contamination due to mining activities in Wadi Asal and Wadi Queih, Red Sea, Egypt. Five groundwater samples were gathered from Middle Miocene, Duwi Formation, and Nubian aquifers. The dominant ions are: Ca2+ > Na+ > Mg2+/Cl– > > for Duwi aquifer, while Asal and Nubian aquifers have Na+ > Ca2+ > Mg2+/Cl– > > . The hydrochemical facies for Duwi aquifer plot in Ca–Na–Cl–SO4 field (40%), and Asal and Nubian aquifers in Wadi Queih (60%) plot in Na–Ca–Cl–SO4 field. The heavy metal contents are as follows: Zn > Pb > Cr > Ni > Cd > Cu for Asal and Pb > Cr > Zn > Ni > Cd > Cu for Queih; all related to mining activities of Pb–Zn and phosphates. Drinking water quality index (DWQI) reveal that all the groundwater samples are improper for drinking. Irrigation water quality index (IWQI) reveal that all groundwater demonstrating a medium quality class for irrigation purposes. Groundwater exploration combined with suitable remediation techniques is recommended for future sustainable development in the investigated zone and similar coastal areas in Egypt. [ABSTRACT FROM AUTHOR]

Identifying nitrate sources and migratory pathways is crucial for controlling groundwater nitrate pollution in agricultural watersheds. This study collected 35 shallow groundwater samples in the Nansi Lake Basin (NLB) to identify groundwater nitrate sources and potential health risks. Results showed that NO3− concentration in 62.9% of groundwater samples exceeded the drinking water standard (50 mg/L). Hierarchical cluster analysis (HCA) was used to classify the sampling points into three groups based on hydrochemical and isotopic data. Groups A and C were situated in the eastern recharge and discharge regions of Nansi Lake, while Group B was located in the Yellow River floodplain west of the lake. Hydrochemical data and nitrate stable isotopes (δ15N–NO3− and δ18O–NO3−) indicated that elevated NO3− primarily originated from soil organic nitrogen (SON) in Group A, while manure and sewage (M&S) were the primary sources in Groups B and C samples. Microbial nitrification was identified as the primary nitrogen transformation process across all groups. The source apportionment results indicated that SON contributed approximately 40.1% in Group A, while M&S contributed about 53.9% and 81.2% in Groups B and C, respectively. The Human Health Risk Assessment (HHRA) model indicated significant non-carcinogenic risks for residents east of Nansi Lake, primarily through the oral pathway, with NO3− concentration identified as the most influential factor by sensitivity analysis. These findings provide new perspectives on identifying and handling groundwater nitrogen pollution in agriculture-dominated NLB and similar basins that require enhanced nitrogen contamination management. [ABSTRACT FROM AUTHOR]

Chlorpromazine (CPZ), an antipsychotic drug derived from phenothiazine, can cause a range of adverse effects in humans, notably visual problems and hematological disorders upon consumption of chlorpromazine‐contaminated water. In this regard, a novel electrochemical sensing platform based on a copper–aluminum‐layered double hydroxide (Cu–Al LDH)‐modified platinum electrode for the highly sensitive and selective detection of chlorpromazine in groundwater samples has been developed. The immobilized Cu–Al LDH showed an electrocatalytic effect on chlorpromazine reduction and oxidation. Among the employed electroanalytical techniques, only the square‐wave voltammetry‐assisted Pt/Cu–Al LDH electrode could detect chlorpromazine with a remarkable sensitivity of 0.065 µA µM−1 over a broad linear detection range of 0.01–760 µM, with low detection and quantification limits of 4.86 and 16.18 nM, respectively. Furthermore, the developed electrode can rapidly detect chlorpromazine within less than 10 s. In addition, the diffusion profiles of steady‐state concentrations of oxidized and reduced chlorpromazine within the immobilized Cu–Al were studied using the Legendre wavelet method. Moreover, the developed Pt/Cu–Al LDH electrode demonstrated satisfactory rates in the quantification of chlorpromazine in groundwater samples, yielding satisfactory recovery rates (97.63–102.57%), confirming the practicability of the fabricated electrode in real‐time monitoring of chlorpromazine levels in groundwater without requiring any sample pretreatment. [ABSTRACT FROM AUTHOR]

The presence of uranium in groundwater has become a growing concern due to its potential health implications. This abstract focuses on the assessment of uranium concentrations in groundwater samples collected from the Kangra district. The study employed rigorous sampling and analysis techniques to evaluate the extent of uranium contamination and its distribution in the groundwater resources of the region. A comprehensive survey was conducted across various locations within the Kangra district, involving the collection of groundwater samples from different depths and geological formations. The collected samples were subjected to meticulous laboratory analysis, employing advanced spectroscopic method of LED fluorimeter to quantify uranium concentrations. The findings reveal varying levels of uranium in the groundwater samples, with concentrations ranging from minimal to elevated levels. The distribution of uranium was observed to be influenced by geological factors, hydrological characteristics, and anthropogenic activities. This research contributes to the understanding of little uranium contamination in the Kangra district's groundwater, serving as a valuable resource for policymakers, researchers, and stakeholders striving to ensure the safety and sustainability of the region's water resources. [ABSTRACT FROM AUTHOR]

Radioactive elements have coexisted in our environment and the health risks assessment for humans associated with the presence of these radioactive elements in the environment is necessary. This study was conducted in the Mansa district of Punjab for estimating the health risks to the people living in the region. 22 Soil and water samples from collected from various locations in the district. The range of Ra, Th and K in the soil samples varied from 28.09 Bq/kg to 55.91 Bq/kg, from 23.32 Bq/kg to 79.64 Bq/kg and from 189.22 Bq/kg to 425.58 Bq/kg, respectively. Doses to different organs have been calculated and ultimately Expected lifetime cancer risk varies from 0.79 × 10−3 to 1.46 × 10−3 for indoor and 0.08 × 10−3 to 0.15 × 10−3 for outdoor which is well below the safe limit of 3.5 × 10−3. The average concentration of Uranium in groundwater samples is found to be 37.95 µg/L, which is above the World Health Organisation's (WHO) standard limit of 30 µg/L. But the values of Life time average daily dose (LADD) and Hazard quotient (HQ) is found to be below the standard limit by WHO. Bones are found to be the most affected organ followed by Kidneys from the study of organ specific doses. The study suggests more intense detailed survey of Mansa district by increasing the number of sampling sites and correlate it with the other water and soil quality parameters. [ABSTRACT FROM AUTHOR]

Aim: Groundwater ecosystems harbour a unique biodiversity, but remain poorly studied, mainly due to difficulties in accessibility and imperfect species detection. Consequently, knowledge on the state and change of groundwater biodiversity remains highly deficient. In the context of global warming and excessive groundwater extraction, understanding groundwater from an ecosystem‐perspective, including organism diversity and distribution, is essential. This study presents the largest ever systematic assessment of groundwater amphipods, which are a key component of European groundwater biodiversity. Location: Switzerland (41,285 km2), including data from 906 sampling sites. Taxon: Groundwater amphipods, genera Niphargus and Crangonyx (Crustacea, Amphipoda). Methods: We applied a highly standardized citizen science approach to collect repeated groundwater fauna samples in collaboration with municipal drinking water providers. Using detection–nondetection data of the genetically identified groundwater amphipod species, we assessed the overall species diversity of both rare and common species. The distribution of commonly found species was predicted using multispecies occupancy modelling. Results: We retrieved 3882 samples from 906 sites, yielding 2350 groundwater amphipod individuals. We identified a remarkable species diversity, comprising few commonly and many rarely found species. Considering commonly found species, we identified distinct distribution ranges, low local species richness and a predominance of negative co‐occurrences. In contrast, a major portion of species were found rarely (generally at just one or two sites each), distributed uniformly throughout the study area and unrelated to common species' recognized hotspots. Many of these rarely found species are not yet formally described. Main Conclusions: Our results give robust emphasis on the rare occurrence and narrow distribution of many groundwater dwellers. Our systematic and standardized sampling data of groundwater amphipods suggest that rarity is particularly prominent and inherent to groundwater organisms. We emphasize the need of systematic data to integrate rare groundwater species in biodiversity assessments, especially in times of global change. [ABSTRACT FROM AUTHOR]

Herbicides (HBCs) are extensively used in modern agriculture. However, their potential negative impacts on environmental media have emerged as a significant environmental concern. In this study, we employed positive matrix factorization (PMF) to identify the potential sources of HBCs. Furthermore, we utilized a multi-matrix ecological risk model to assess the risks associated with HBCs in both surface water and groundwater in the black soil region of Northeast China. The findings revealed that the levels of ∑ 15 HBCs in surface water and groundwater ranged from 585.84 to 6466.96 ng/L and 4.80 to 11,774.64 ng/L, respectively. The PMF results indicated that surface runoff and erosion accounted for 50% of the total HBCs in water, serving as the primary sources. All tested HBCs exhibited acute risk values within acceptable levels. The risk index for the ∑ 15 HBCs was categorized as "moderate risk" in 31% of the surface waters and 13% of the groundwaters. However, 4% of the groundwater sampling sites reached the "high risk" level. The chronic risk quotient of ∑ 15 HBCs in surface water and groundwater was 92% and 62% at the "high risk" level, respectively. Interestingly, non-carcinogenic HBCs contributed more significantly to the ecotoxicology of the aquatic system than carcinogenic HBCs. This study provides comprehensive information on the legacy of HBCs in water bodies and emphasizes the potential risks posed by HBCs to aquatic systems. The results obtained from this study could help relevant management authorities in developing and implementing effective regulations to mitigate the ecological and environmental risks associated with HBCs. [Display omitted] [ABSTRACT FROM AUTHOR]

El Qaa plain is one of the promising areas for agriculture projects, owing to its soil and groundwater resources. So, 14 groundwater samples were collected, chemically analyzed, hydrochemical (ratios, models and plots) and GIS techniques were applied, to evaluate the factors governing this water chemistry and suitability for irrigation. The results indicated the expansion of the agricultural area 8 times in the last 2 decades. The water can be divided into two groups; (A) freshwater (TDS ≤ 1000) in the eastern part of the study area within the clastic weathered basement rocks part of the aquifer, and (B) saline water (TDS > 1000) in the western part within the carbonates and evaporites rich sediments and close to the Gulf of Suez. The deduced factors controlling groundwater chemistry were precipitation, evaporites dissolution, seawater intrusion and ion exchange process. The calculated sodium absorption ratio (SAR) was < 10 indicating the good quality of this water for irrigation without sodicity hazard. Water of Group (A) (electric conductivity < 2250µS/cm) can be used safely for irrigation without any impact of salinity on all types of soil and plants. Group (B) water (electric conductivity > 2250µS/cm) has salinity hazard and can be used for irrigation on well-permeable soils and salt-tolerant plants. The concentrations of the studied potentially toxic elements (PTEs) were within the permissible limit for irrigation. Expansion in agricultural activities has adverse impact on groundwater quality. So, eco-friendly fertilizers should be applied in this promising area with the application of hydrologic pumping advises to safe aquifer quality from the degradation. [ABSTRACT FROM AUTHOR]

This study aims to optimize ammonium removal from NH4Cl‐enriched groundwater at different concentrations using an electrodialysis (ED) process. A customized design (CD) based on response surface methodology (RSM) was employed to develop predictive models and improve the performance of the demineralization system. Ion removal efficiency was evaluated in 32 unique experimental configurations, taking into account variations in three input parameters: voltage (A), initial ammonium concentration (B) and demineralization rate (C). These parameters were selected for their impact on two response variables: electric conductivity (Y1) and final ammonium concentration (Y2). An in‐depth analysis of variance (ANOVA) was performed to examine the variables and their interactions. The results indicated that Y1 was significantly influenced by C, while Y2 was influenced by B. In addition, the predictive models demonstrated strong correlations, with a coefficient of determination (R2) greater than 0.88 for both response variables. The RSM approach applied to optimize the parameters studied identified the following optimum values: 14.17 V for A, 1 mg/L for B and 70 % for C, giving Y1 of 215.377 μS/cm and Y2 of 0.279 mg/L. [ABSTRACT FROM AUTHOR]

Emerging pathogenic fungi have become a topic of conservation concern due to declines observed in several host taxa. One emerging fungal pathogen, Ophidiomyces ophidiicola, is well documented as the causative agent of ophidiomycosis, otherwise known as snake fungal disease (SFD). O. ophidiicola has been found to cause disease in a variety of snake species across the United States, including the eastern massasauga (Sistrurus catenatus), a federally threatened rattlesnake species. Most work to date has involved detecting O. ophidiicola for diagnosis of infection through direct sampling of snakes, and attempts to detect O. ophidiicola in the abiotic environment to better understand its distribution, seasonality, and habitat associations are lacking. We collected topsoil and groundwater samples from four macrohabitat types across multiple seasons in northern Michigan at a site where Ophidiomyces infection has been confirmed in eastern massasauga. Using a quantitative PCR (qPCR) assay developed for O. ophidiicola, we detected Ophidiomyces DNA in topsoil but observed minimal to no detection in groundwater samples. Detection frequency did not differ between habitats, but samples grouped seasonally showed higher detection during mid-summer. We found no relationships of detection with hypothesized environmental correlates such as soil pH, temperature, or moisture content. Furthermore, the distribution of Ophidiomyces positive samples across the site was not linked to estimated space use of massasaugas. Our data suggests that season has some effect on the presence of Ophidiomyces. Differences in presence between habitats may exist but are likely more dependent on the time of sampling and currently uninvestigated soil or biotic parameters. These findings build on our understanding of Ophidiomyces ecology and epidemiology to help inform where and when snakes may be exposed to the fungus in the environment. [ABSTRACT FROM AUTHOR]

Groundwater, a vital source of water supply, is currently experiencing a pollution crisis that poses a significant risk to human health. To understand the hydrochemical formation mechanisms, quality and risk to human health of groundwater in the upper reaches of the Wulong River basin, 63 sets of groundwater samples were collected and analyzed. A combination of mathematical statistics, correlation analysis, Gibbs diagram, ion ratio, and cation exchange were comprehensively employed for hydrochemical analysis, and further water quality index (WQI) and human health risk assessment were conducted. The results indicate that groundwater is generally neutral to weakly alkaline. The dominant cations in the groundwater are Ca2+ and Mg2+, while the main anions are HCO3− and SO42−. The hydrochemical types of groundwater mainly include HCO3·SO4-Ca, HCO3-Ca and HCO3-Na. The diverse hydrochemical types are mainly due to the fractured and discontinuous nature of the aquifers. The hydrochemical characteristics are influenced by the dissolution of silicate and carbonate minerals, cation exchange processes, and anthropogenic pollution. The presence of NO3− in groundwater is primarily attributed to agricultural activities. The groundwater is mainly categorized as "Good" (36.6%) and "Poor" (60.8%). "Very poor" and "Excellent" categories are rare, accounting for only 1.2% and 1.4%, respectively, and no samples are classified as "Non-drinkable". The Ewi for NO3− is the highest, indicating severe contamination by anthropogenic NO3− pollution. Human health risk assessment reveals that water samples posing exposure risks account for 82.54% for children and 79.37% for adults. This study highlighted that anthropogenic nitrate pollution has deteriorated groundwater quality, posing risks to human health. It also suggests an urgent need to enhance research and protective measures for groundwater in similar regions, such as the Shandong Peninsula. [ABSTRACT FROM AUTHOR]

In urban areas with dense populations and high water demands, effective management of water resources is crucial for sustainable development. It includes optimizing water usage and recycling wastewater to balance supply and demand. Urban rivers, which now carry sewage year-round due to increased urban water consumption, are increasingly used for irrigation in peri-urban regions. This study aims to assess the suitability of an urban stream for irrigation compared to catchment groundwater, using hydrochemical parameters to evaluate water quality indices. Analysis of major ion distribution from upstream to downstream reveals a significant increase of TDS (r2 = 0.65; p < 0.001) in the surface water and a decrease (r2 = 0.93; p < 0.001) in groundwater samples. The calculated Weighted Arithmetic-Water Quality Index (WA-WQI) indicates that around 85% and 75% of surface water and groundwater samples from the Musi river are classified as very poor to unsuitable for any use, highlighting critical pollution levels. Based on irrigation suitability indices, only 16% of the surface water samples and 60% of the groundwater samples are suitable for irrigation. The nitrate concentration increased from less than 10 mg l−1 in the upstream region to over 100 mg l−1 in the urban stretch. Nitrogen-Phosphate-Potassium (NPK) ratios across the basin are exceptionally higher, representing crops irrigated using the Musi river water might not require fertilizer applications. The adoption of fertilizer application concerning supplied water hydrochemistry, particularly the NPK ratio, might limit the excess usage of fertilizer and benefit farmers. Additionally, this practice may also limits the excess input of nitrate to the groundwater in the Musi river basin. [ABSTRACT FROM AUTHOR]

The Kingdom of Saudi Arabia is facing challenges related to water scarcity, however, the Cambrian-Ordovician Saq Aquifer System, in Al Qassim Province, provides vital water resources. This article assesses the petrophysical properties and hydrochemical characteristics of the aquifer system utilizing downhole cam recording and geostatistical analysis. The evaluation aims to assign the hydrogeological attributes, groundwater potential, and associated risks using an open-petrophysical aquifer system approach. The petrophysical evaluation appraises the prevailing lithology, zonation, hydrogeological properties, and salinity patterns. Sandstones with low shale content and dispersed distribution possess effective porosity that is fully saturated with groundwater containing calcium and bicarbonate ions. The majority of groundwater samples exhibit simple dissolution or lack prevailing ionic concentrations, indicating an ancient marine water genesis and a fossilized water type. The resistivity-depth profiles reveals three potential water-bearing aquifers including a disconnected compartment of an unconfined aquifer, a continuous compartment of a confined aquifer, and a continuous compartment of an unconfined aquifer. Petrophysical and hydrochemical parameters have been analyzed using geostatistical methods to assess their spatial variability and reduce potential sampling errors. Three distinct risk segments (RSs) with varying levels of risk characterize the aquifer system. RS-A represents a potential aquifer with low risk, RS-B poses moderate risks, and RS-C carries high risks. A fairway map of the aquifer system assigns geologic-hydro related factors that influence aquifer assessment and risk mapping. Segment-A is deemed an attractive long-term investment opportunity with low risk, while Segment-B offers a good investment opportunity with moderate risk. Segment-C provides a fair investment opportunity but entails high risks related to petrophysical qualities, hydrochemical characterizations, and irrigation utilities. The extraction and utilization of groundwater present promising investment opportunities, while employing a petrophysical approach can effectively evaluate and manage groundwater resources for sustainable utilization. [ABSTRACT FROM AUTHOR]

Groundwater is extensively utilized for drinking, irrigation, and industrial activities globally. However, its quality is deteriorating significantly, particularly in coastal regions where saline water infiltration is a major issue. This study investigates the coastal aquifer of Udupi district in Karnataka, India, covering approximately 80 km2, through hydro-geochemical analysis of groundwater samples from 57 spatially distributed locations, pre- and post-monsoon. The major anion and cation parameters analyzed include Cl−, HCO₃−, SO42−, NO₃−, Na+, Ca2+, K+, and Mg2+. The analysis revealed a pH range of 2.9 to 8.3, indicating acidic to slightly alkaline conditions, and total dissolved solids (TDS) concentrations ranging from 110 to 6683 mg/L, predominantly showing saline characteristics toward the coastline. Hydrogeochemical assessment, including Chadha's plot, identified Na-Cl type water in most samples, indicating the influence of salinity. Approximately 21% of pre-monsoon and 67% of post-monsoon samples were deemed unsuitable for irrigation based on permeability index values, with 2 to 3% exhibiting high salinity hazards. The variation in correlation coefficients between pre-monsoon and post-monsoon periods suggests that saline water intrusion, freshwater recharge, and geochemical interactions influence the coastal groundwater system. The molar ratio of Na⁺ to Cl− suggested a reverse cation exchange process, highlighting the complex interactions between saline and freshwater. Overall, 79% of pre-monsoon and 80% of post-monsoon samples were deemed suitable for irrigation, while 21% and 20% were classified as completely unsuitable, respectively. [ABSTRACT FROM AUTHOR]

To analyze groundwater contamination with uranium, groundwater samples were collected from the major industrial area of Jalandhar, Punjab, India (as the industrial effluent is found to contain a large number of heavy metals) and analyzed using ICPMS (Inductively Coupled Plasma Mass Spectrometer) for uranium-238. Uranium-238 concentrations in groundwater ranged from 4.96 µg/L and 38.52 µg/L, with an average of 17.0 µg/L. All the values of uranium concentration and uranium activity concentration in the samples were found within the permissible range by the World Health Organization (WHO). The hazard quotient for all the samples is found to be below one, indicating very low or no risk to the population. [ABSTRACT FROM AUTHOR]

A study to assess the uranium exposure due to ingestion of groundwater in Fatehabad district of Haryana has been carried out. Total 49 drinking water samples were collected from different locations of the district. Two groundwater tests taken near the power plant site exceeded the World Health Organization's recommended threshold limit of 30 μg L−1 (WHO in Guidelines for drinking-water quality, 4th edn, World Health Organization, Geneva, pp 1–564., 2011). The average radiological and chemical toxicity risks are below recommended limit. Because of their high organ sensitivity, babies are found to have the highest annual effective dose among the several life stage groups for which it was estimated. Positive correlations were found between the content of uranium in groundwater samples and EC, TDS, salinity, redox potential, and dissolved oxygen whereas a negative connection with pH has been noted. Organ-specific dosage resulting from uranium ingestion has been investigated using the hair compartment model. [ABSTRACT FROM AUTHOR]

The present investigation aims to assess the processes controlling the composition of groundwater in the Sohagpur coalfield and its quality concerning drinking and irrigation purposes using hydrogeochemical and statistical approaches, water quality indices, and a geographic information system (GIS). Twenty-seven groundwater samples collected from different sites were analysed for electrical conductivity (EC), pH, turbidity, major anions and cations, total dissolved solids (TDS), and total hardness (TH). The study results show that the pH of samples varied from 5.97 to 8.26, suggesting the acidic to slightly alkaline nature of the water samples. The TDS ranged from 265 to 1450 mg/L with 78% of the samples being in the freshwater category. The Ca2+-Mg2+-SO42− and Ca2+-Mg2+-HCO3− are dominant hydrogeochemical facies in the Sohagpur coalfield. The hydrogeochemical and statistical methods show that the groundwater chemistry of the Sohagpur coalfield is primarily controlled by the dissolution and weathering of minerals and secondarily due to the influence of anthropogenic activities (i.e., agricultural practices, sewage, and animal waste discharge). In the majority of the groundwater samples, concentrations of TH, TDS, turbidity, and SO42− exceeded the Bureau of Indian Standards (BIS) drinking acceptable limits and suggested that water is unsuitable for direct consumption. Moreover, the estimated water quality index (WQI) indicated that 52% of the samples (especially from the Dhanpuri and Amlai areas) belong to poor to unfit water categories. High values of EC in 56% of the samples and magnesium hazard (MH) at two sites restrict the irrigation suitability at these locations. [ABSTRACT FROM AUTHOR]

Groundwater quality is a serious concern in alluvial aquifers undergoing vast agricultural transformation around the globe. Mehsana district of Gujarat is an example of agricultural landscape having most of the seasonal crops and vegetables. Groundwater samples were collected in monsoon 2017 and pre-monsoon 2018 to analyze major ions and isotopes to derive the hydrochemistry. The hydrochemical facies reveal Na+–Cl−, Na+–HCO3− and Ca2+–HCO3− type water suggesting complex hydrochemical reaction taking place in the region. The scatter plot of Ca2+ + Mg2+ versus HCO3− + SO42− and Na+ versus Cl− shows the ion exchange and silicate weathering along with intermixing of saline water. The presence of high sodium, alkaline pH and bicarbonate promotes the release of fluoride from minerals in groundwater which is high during monsoon. The fluoride concentration increases progressively along the Sabarmati River. The spatial variation map of nitrate in the district shows both point and non-point sources of NO3− contamination. This evidence will support the strong contribution of agricultural activities, as shown by land use that long-term flood irrigation practices have enhanced this impact. The deep aquifers are suitable for drinking purposes as compared to shallow aquifers which are affected with NO3− pollution due to the leaching process during the pre-monsoon season. The agriculture indices show contaminated groundwater for irrigation in more than 50% of wells. The composition of isotopes varied between (δ18O − 2.08 to − 4.41‰ and δD − 19.19 to − 32.28‰). The groundwater trendline was found below the local meteoric water line which indicates evaporation due to semiarid climate before infiltration. [ABSTRACT FROM AUTHOR]

Due to over exploitation of groundwater, there is a drastic decrease in groundwater level and its quality. The groundwater samples have been analysed to estimate its aptness for domestic and agricultural in Sivakasi Taluk industrial areas. In the course of post monsoon and summer of 2020, twenty two samples have been collected from the research area. The groundwater samples were examined for various parameters like pH, EC, TDS, TA, TH, Ca2+, Mg2+, K+, Na+, Cl−, SO4−, HCO3−, F−, DO and samples were compared with BIS, WHO and ICMR standards. It is inferred through results that EC and TDS values were spiked up due to excess presence of Cl−, Na+, Ca2+, Mg2+, F− and NO3− present in water samples near the industrial areas and natural rock formation. The water samples were evaluated for their suitability for irrigation and were assessed by SAR, % Na, Kelly's ratio and MH, USSL diagram shows majority of the samples are apt for agricultural. Piper plot indicates that majority of the collected samples fall under the Na–Cl category thereafter by Mg- HCO3- Cl, Ca–Mg–Cl and Na + K –Cl types and this infers anthropogenic influences. Gibb's plot shows that the collected samples fall under evaporation dominion field followed by rock-water dominion field of the two seasons. It is recommended to provide Artificial Recharge structures, recharge ponds in the area of research to increase the under-groundwater level and its standard. [ABSTRACT FROM AUTHOR]

Determining groundwater quality status and hydro-geochemistry of an aquifer is crucial to ensure cleaner and safer water for human consumption. Groundwater sustainability issues are getting attraction due to global warming and complexities in land utilization. These concerns increased the challenge of gaining an appropriate comprehension of anthropogenic activities and natural processes, as well as how they influence the quality of surface water and groundwater systems. In the present investigation, 48 groundwater samples were collected and analyzed from the Panchkula district of Haryana, located in the Upper Ghaggar River Basin, to explore the sources and driving factors responsible for hydro-geochemistry of the aquifers falling under the natural and anthropogenically intervened areas. Groundwater sampling was carried out in the premonsoon (PRM) as well as postmonsoon (POM) seasons to examine the spatio-seasonal variations in its quality. The results of the study revealed that reverse ion exchange processes are mainly controlling the aquifer geochemistry in areas occupied by natural vegetation, while the nitrate and chloride content of groundwater was the result of anthropogenic activities. The mechanisms governing groundwater quality and the related hydro-geochemical processes were assessed using binary plots of different cations and anions, along with the Gibbs plot and chloro-alkaline indices (CAI). Saturation indices (SI) indicated that groundwater was over-saturated with respect to dolomite, calcite, and aragonite, while 68.75% and 50% of samples indicated under-saturation with respect to anhydride and gypsum, respectively. Principal component analysis (PCA) and Pearson's correlation coefficients were also considered to affirm the processes taking place to control the aquifer chemistry. Groundwater in the majority of the area was found suitable for drinking purposes except in the locations where high nitrate concentrations were recorded, thus suggesting the use of water treatment facilities for such areas. [ABSTRACT FROM AUTHOR]

Water quality is crucial to the environmental system and thus its chemistry is important, and can be directly related to the water's source, the climate, and the geology of the region. This study focuses on analyzing the hydrochemistry of specific locations within the Dakhla Oasis in Egypt. A total of thirty-nine groundwater samples representing the Nubian Sandstone Aquifer (NSSA) and seven surface water samples from wastewater lakes and canals were collected for analysis. Key parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) were measured on-site, while major ions and trace elements (Fe+2 and Mn+2) were analyzed in the laboratory. The water quality index (WQI) method was employed to assess the overall water quality. Hydro-chemical facies were investigated using Piper's, Scholler's, and Stiff diagrams, revealing sodium as the dominant cation and chloride, followed by bicarbonate as the dominant anion. The hydro-chemical composition indicates that Na–Cl constitutes the primary water type in this study. This points to the dissolution of evaporates and salt enrichment due to intense evaporation resulting from the region's hyper-aridity. In groundwater samples, the order of hydro-chemical facies is HCO3− > Cl− > SO4−2 > Na+ > Ca+2 > K+ > Mg+2, while in wastewater samples, it is Cl− > Na+ > SO4−2 > HCO3− > Ca+2 > Mg+2 > K+. When considering iron and manganese parameters, the water quality index (WQI) values suggest that most groundwater samples exhibit excellent to good quality but become poor or very poor when these elements are included. This study could prove valuable for water resource management in the Dakhla Oasis. [ABSTRACT FROM AUTHOR]

The Sierra Seca aquifer system is located in the northeast (NE) of the province of Granada, in the Prebetic Domain (Betic Cordillera). It is composed of different aquifer units hosted in the Lower Cretaceous and Upper Cretaceous limestones. The two aquifers are separated by a low permeability marl layer, which effectively acts as a barrier between them. To outline the behavior of the hydrogeological system, 407 samples of precipitation and 67 samples of groundwater were obtained from May 2020 to Oct. 2022 and isotopically ( δ 18 O and δ 2 H ) analyzed. For the estimation of the recharge elevation, a new methodology has been applied to estimate the isotopic content of recharge as a function of precipitation. This allowed the evaluation of the vertical gradient of both precipitation ( ∇ Z δ 18 O P = − 2.9   ‰ / k m ) and aquifer recharge ( − 4.4   ‰ / k m ≤ ∇ Z δ 18 O R ≤ − 2.9   ‰ / k m ). Therefore, estimating (1) the recharge zone elevation associated with the aquifer system, which is comprised between 1500 and 1700 m a.s.l., and (2) the transit time of recharge to reach the outflow point of the aquifer system, which varies between 4 and 5 months, is possible. Additionally, three tracer tests were conducted to outline the hydrologic connection between the recharge and discharge zones of the aquifer system. The results show that the Fuente Alta spring drains the limestones of the Lower Cretaceous, while La Natividad spring does the same with the limestones of the Upper Cretaceous. In the case of the Enmedio spring, groundwater discharge is related to infiltration through the streambed of the watercourse fed by the Fuente Alta spring. [ABSTRACT FROM AUTHOR]

It is imperative to eliminate heavy metals and pharmaceutical residual pollutants from wastewater to reduce their detrimental effects on the environment. In this work, natural zeolite and a 2-amino terephthalic acid-based multi-metallic organic framework were used to create a new composite that can be utilized as an adsorbent for cadmium and safinamide. The adsorption study was examined in a variety of settings (pH, adsorbent dosage, pollutant concentration, and time). Moreover, Zeta potential, BET, SEM, FTIR, XRD, and SEM measurements were used to characterize the adsorbents. The adsorption process was confirmed using FTIR, XRD, and SEM analysis. Various nonlinear adsorption isotherm models were applied to adsorption results. The results showed a significantly better adsorption ability for safinamide and cadmium using zeolite/MOF compared to zeolite. Adsorption kinetics were represented by five models: pseudo first-order, pseudo second-order, intraparticle diffusion, mixed first- and second-order, and the Avrami model. Regarding both adsorbent substances, safinamide adsorption was best represented by the intraparticle diffusion model. In contrast, the pseudo second-order and intraparticle diffusion models for zeolite and zeolite/MOF, respectively, better fit the experimental results in the case of cadmium adsorption. The thermodynamic parameters ΔH°, ΔS°, and ΔG° were investigated through temperature tests carried out at 25, 35, 45, and 55 °C. Exothermic and spontaneous adsorption processes were demonstrated by the computed values. The study of adsorbent regeneration involved the use of several chemical solvents. The DMSO solvent was shown to have the highest adsorbent regeneration method efficiency at 63%. Safinamide elimination was lessened by organic interfering species like cefixime and humic acid compared to inorganic species like chloride, sulphate, and nitrate, most likely as a result of intense competition for the few available active sites. Using zeolite/MOF nanocomposite, the percentage of safinamide removed from spiked real water samples (tap water, Nile River water, and groundwater samples) was 48.80%, 64.30%, and 44.44%, respectively. Based on cytotoxicity results, the highest percentages of cell viability for zeolite and zeolite/MOF at 24 h were 83% and 81%, respectively, in comparison to untreated controls. According to these results, zeolite and zeolite/MOF composites can be used as effective adsorbents for these pollutants in wastewater. [ABSTRACT FROM AUTHOR]

Good quality water for human consumption, irrigation, and industrial use is very important. Today, around the world, water is contaminated by natural processes and human activities. This study aimed to evaluate the suitability of groundwater for drinking and irrigation, identify the source of fluoride and nitrate contamination, and assess the human health risks around the Cauvery River basin in southern India. A total of 30 groundwater samples were collected and analyzed for hydrochemical parameters, including EC, TDS, pH, Ca, Mg, Na, K, HCO3, Cl, SO4, NO3, and F−. The majority of groundwater samples in the study area are used for drinking and irrigation. The pH of groundwater in the study area was observed to be dominantly alkaline. The levels of TDS, Ca, Na, K, F, and TH exceeded the permissible limits recommended by BIS and WHO. Fluoride and nitrate levels in groundwater exceeded the permissible limits for drinking purposes in 43% and 50% of the samples, respectively. The excessive concentration of fluoride and nitrate in groundwater could pose serious human health problems. Fluoride and nitrate concentrations in groundwater vary between 0.1 and 2 mg/l and 12 and 95 mg/l, respectively. Based on the computation of the drinking water quality index, about 73% of groundwater samples were classified as excellent to good. Health risk was assessed for infants, children, and adults using non-carcinogenic risk indices such as hazard quotients (HQ), hazard indexes (HI), total hazard indices (THI), and carcinogenic risk indices (CR). Infants, children, and adults have different total hazards indexes ranging from 1.508 to 5.733, 1.579 to 6.003, and 0.011 to 0.046, respectively. Health risk assessment results indicated that the hazard index and hazard quotient were above the recommended limit of > 1 in most of the samples for infants and children. Non-carcinogenic risk and carcinogenic risks were more likely to affect infants and children rather than adults through ingestion of contaminated water. [ABSTRACT FROM AUTHOR]

Many coastal and island communities depend on groundwater as the only source of freshwater, making it an invaluable resource. In the Mediterranean region, groundwater resources are highly vulnerable to natural and anthropogenic pressures, such as overexploitation, climate change, seasonal variations in precipitation, and seawater intrusion. Hence, an understanding of hydrogeological processes and groundwater chemistry is a basis for the sustainable management of coastal and island groundwater resources. Vis, a small and remote karst island in the Adriatic Sea, exhibits peculiar geological and hydrogeological settings, resulting in the island's autonomous water supply. The current pumping capacity (maximum of 42 l/s) meets most of the demand, but intensive summer tourism and climate change exert high stress on groundwater resources during the dry season. Consequently, in the last decade, occasional reductions for consumers occurred. Monitoring of in situ physicochemical parameters and groundwater sampling for chemical and isotopic analyses were conducted from 2020 to 2023 at deep borewells, shallow dug wells, and springs. Hydrochemical interpretation indicated that groundwater chemistry was affected primarily by carbonate and sulfate rock dissolution, mixing with seawater, reverse ion exchange, and dedolomitization. The majority of groundwater samples exhibit Ca–HCO3 hydrochemical facies, followed by Na–Cl and mixed facies. The low percentage of seawater in the mixture indicated that seawater intrusion is not too extensive even during prolonged dry periods, implying a favorable hydrostatic regime with relatively small but sufficient groundwater reserves of the island's aquifers, although the investigated period was characterized by significantly lower precipitation with respect to the 30-year average. [ABSTRACT FROM AUTHOR]

Nitrate contamination in drinking water is now gaining global attention because of its potential effect on human health. In this study, nitrate concentrations and their potential sources in groundwater and surface water were investigated using hydrochemical and isotopic methods. The physical parameters were measured in-situ using multi parameter meters; major ions, stable isotopes (δ2H and δ18O of H2O) and δ15N and δ18O of NO3− were measured using the Ion Chromatography, laser spectrometry and titanium (III) reduction method respectively. The results indicate that the dominant water type is Ca-Mg-HCO3, followed by the Ca–Mg–Cl hydrogeochemical facies. The plot of NO3−/Cl− against Cl− revealed that the dominant sources of NO3− in the groundwater are manure/sewage with few traces from soil inputs. Meanwhile the plot of δ2H-H2O against δ18O-H2O showed that rainfall is the main source of groundwater recharge with few groundwater samples showing evidence of recharge from an enriched source (Black Volta River). The plot of δ18O – NO3− against δ15N – NO3− suggests that a significant percentage of nitrate is from manure and sewage, followed by the soil zone, hence leading to nitrification and denitrification being important biological processes affecting NO3− concentrations in groundwater in the study area. The stable isotope mixing model suggests manure contributed a mean proportional contribution of about 74% of NO3− to groundwater in the study area, while soil nitrogen contributed 10%. The Nitrate Pollution Index (NPI) suggests that about 80.2% of water samples were pollution free, while anthropogenic activities resulted in about 8.3% of the pollution index. Since most samples with lower nitrate pollution indices were observed around recharged areas and increased toward the discharge points, our study suggests the possibility that recharge areas of the water was free or lowest in nitrate contamination. [ABSTRACT FROM AUTHOR]

There has been a significant rise in cancer-related mortality in the Ladakh region during the past 10 years. The most common type of case is gastrointestinal cancer, which has been linked in theory by medical research to lifestyle factors, high altitude conditions, and the prevalence of Helicobacter pylori bacteria brought on by poor hygiene. Nevertheless, the precise cause of the rise in cancer cases is still unknown. Concurrently, there has been a significant change in Ladakh's water use practices due to development, improved basic utilities, and related vocational shifts. The local population has become increasingly reliant on groundwater since it provides a year-round, continuous water supply for home and agricultural uses. In this study, we assessed heavy metal contamination in groundwaters and associated human health risks. The results indicate that 46–96% of the groundwater samples have heavy metal pollution with a health hazard index > 1, which means using these groundwaters for drinking, food preparation, and agriculture is likely to result in carcinogenic and non-carcinogenic health hazards. The main heavy metal contaminants found in the groundwater of the Leh district include Cr, As, Hg, and U. According to the health risk assessment, 46–76% of the groundwater samples contain unsafe levels of Cr and As. Prolonged exposure to these levels is likely to cause gastrointestinal cancer in the local population. Acute to chronic exposure to U and Hg concentrations present in some groundwater samples is likely to result in various non-carcinogenic health risks. [ABSTRACT FROM AUTHOR]

Closed basin accounts for about one‐fifth of the global land area and is an important part of the global terrestrial carbon cycle. Due to its relatively close geographical environment and independent carbon cycling system, it is an ideal place to study regional carbon cycling. Here we present a carbon‐related proxy dataset for the Shiyang River Basin in the eastern part of the Hexi Corridor. The dataset collected carbon‐related indicator data for 997 sediment samples from 14 profiles, 92 surface sediment samples and 25 groundwater samples. It includes total nitrogen (TN), total organic carbon (TOC), inorganic carbon (IC), carbon‐nitrogen ratio (C/N), organic carbon isotopes (δ13Corg), carbonate carbon isotopes (δ13Ccarb), oxygen isotopes (δ18O) and other proxy indicator data, as well as profile and groundwater age data. These data will play an important role in studying organic carbon sinks, inorganic carbon sinks, carbon cycling processes and environmental changes in the closed basin. This dataset can be downloaded from https://doi.org/10.5281/zenodo.10252702. [ABSTRACT FROM AUTHOR]

A complete understanding of groundwater dynamics and its interaction with surface water under the impact of agricultural activities is vital for local agriculture, ecology, and residents of dry regions, which is not commonly recognized in arid areas. This research outlines the geochemical characteristics, recharge sources, and potential factors impacting groundwater quality in a new land reclamation located in the small basin of Abu Mina, which is part of the Western Nile Delta region.1 Thirty-one groundwater samples and two surface water samples were collected in 2021 to represent the Pleistocene aquifer and were subjected to multivariate statistical, hydrochemical, and stable isotope analyses. Data analysis demonstrates that Na+ > Ca2+ > Mg2+ > K+ and SO42– > Cl– > HCO3– > NO3– are the predominant cations and anions, respectively. Groundwater salinity ranged from 465.60 to 6455.18 mg/l, with slightly alkaline. Most of the water samples fall into one of three types of facies: Ca–Cl, Na–Cl, and Mixed Ca–Mg–Cl, in decreasing order. The meteoric genesis index (r2) indicates that deep meteoric water percolation dominates the Pleistocene aquifer. The aquiline diagrams, correlation matrix, and different ionic ratios indicate that evaporation, reverse ion exchange reactions, and the dissolution of carbonate and silicate minerals are the main processes governing groundwater chemistry. Factor analysis (FA) indicated that three factors explain groundwater hydrochemistry, accounting for 71.98% of the total variance. According to the rotating components matrix (F1–F3), the chemistry of the Quaternary aquifer is principally affected by evaporation, ion exchange reactions, and anthropogenic influences. Additionally, salinity increases due to the return flow of irrigation activities and mixing between old and recent water. The stable isotopes (δ18O and δ2H) indicate that the Quaternary aquifer receives groundwater recharge through the return flow of excess irrigation and canal seepage. Under desert reclamation conditions, groundwater salinization processes should be given special consideration. All groundwater samples are appropriate for agricultural irrigation based on the Sodium Adsorption Ratio (SAR), Permeability Index (PI), Percent Sodium (%Na), and Residual Sodium Carbonate (RSC). [ABSTRACT FROM AUTHOR]

Radionuclides predominantly contribute to the radiological and chemical doses incurred by human beings. Among numerous radionuclides, uranium stands out as the primary contributor to human exposure, raising concerns on a global scale. The presence of radionuclides in groundwater presents a notable health risk to individuals consuming the water and the surrounding environment. Groundwater samples collected from various locations in the Nawanshahr and Rupnagar districts of Punjab, India, underwent analysis to estimate uranium levels. The concentration range in the studied areas varied from 11.98 to 67 μg l−1. The study disclosed the retention of uranium in various organs and tissues, including the kidneys, liver, skin, gastrointestinal tract, bones, and urinary bladder. Time-dependent studies indicated a non-saturation behavior of uranium in bones, liver, kidneys, and other soft tissues. Dosimetric models were employed to calculate radiological doses for specific organs and assess chemical toxicity, forming a crucial component of a comprehensive health risk assessment. [ABSTRACT FROM AUTHOR]

Recharge to and flow within the Columbia River Basalt Group (CRBG) groundwater flow system of northeastern Oregon were characterized using isotopic, gas, and age‐tracer samples from wells completed in basalt, springs, and stream base flow. Most groundwater samples were late‐Pleistocene to early‐Holocene; median age of well samples was 11,100 years. The relation between mean groundwater age and completed well depth across the eastern portion of the study area was similar despite differences in precipitation, topographic position, incision, thickness of the sedimentary overburden, and CRBG geologic unit. However, the lateral continuity in groundwater age was disrupted across large regional fault zones indicating these structures are substantial impediments to groundwater flow from the high‐precipitation uplands to adjacent lower‐precipitation and lower‐elevation portions of the study area. Recharge rates calculated from the age‐depth relations were <3 mm/yr and independent of the modern precipitation gradient across the study area. The age‐constrained recharge rates to the CRBG groundwater system are considerably smaller than previously published estimates and highlight the uncertainty of prevailing models used to estimate recharge to the CRBG groundwater system across the Columbia Plateau in Oregon and Washington. Age tracer and isotopic evidence indicate recharge to the CRBG groundwater system is an exceedingly slow and localized process. Article impact statement: Recharge to the Columbia River Basalt groundwater system in northeast Oregon is considerably smaller than previously published estimates and models. [ABSTRACT FROM AUTHOR]

The study implemented Geographic Information System (GIS) techniques and multivariate hydrogeochemical analysis to evaluate the spatial-temporal and seasonal variation in the groundwater quality of Patna, India. For this purpose, sixty groundwater samples were collected and analyzed for major anions and cations during the pre-monsoon, monsoon, and post-monsoon seasons of 2019-2020. The physicochemical parameters such as pH, EC (Electrical Conductivity), TDS (Total Dissolved Solids), TH (Total Hardness), Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO4 2- were considered to evaluate the water quality index. The result revealed degradation in groundwater quality from pre-monsoon (49.21) to post-monsoon (74.48). EC, TDS, TH, Mg2+, Na+, Ca2+, K+, and HCO3- ions were found accountable for high WQI values at various sampling sites during different seasons. Spatial maps showed that 45 % of the sampling stations exhibited poor quality in all three seasons, where the eastern part of the studied region was revealed to be the most affected area. The application of multivariate statistical methods and hydrogeochemical investigation has clearly defined the dominant role of the weathering process, and reverse ion exchange mechanism in controlling the aquifer's ionic chemistry. Moreover, poor seepage system, and waste leachate from the surface have been found as the main cause of high levels of Na+, K+, and Cl- in the eastern part of Patna. [ABSTRACT FROM AUTHOR]

Iodine is one of the essential trace elements in the human body, and excessive or insufficient intake will affect human health. To ensure the safety of drinking water resources, the spatial distribution of iodine content and migration enrichment factors in shallow underground salty water in Tianjin coastal area were studied. The results show that the iodine (as I−) content of shallow groundwater ranges from not detected (ND) to 1320 μg/L, and high iodine groundwater (100–300 μg/L) and super-high iodine groundwater (> 300 μg/L) account for 37.5% of the groundwater samples, distributed in the east, west, central and south of the study area; iodine-deficient groundwater (< 25 μg/L) accounts for 10% of the groundwater samples, and iodine-suitable groundwater (25–100 μg/L) accounts for 15% of the groundwater samples. From north to south and from northwest to southeast, the shallow groundwater in the study area changed from freshwater and brackish water to saline and salt water; the I− concentrations in freshwater, brackish water, and saltwater were significantly different, and the I− concentrations tended to increase with the increase of TDS concentration; the main hydrochemical types in this direction changed as HCO3-Ca·Na → Cl·SO4-Na·Mg → HCO3·Cl-Na·Ca → Cl·HCO3-Na → Cl-Na type shift; high iodine and super-high iodine groundwater chemistry types are mainly Cl-Na type, Cl·HCO3-Na type and HCO3-Ca·Na type. The main source of iodine in groundwater is inferred to be marine sediments. Sedimentary iodine is released during dissolution of marine sediments. I− concentrations increase along with the groundwater flow. In the eastern area, the poor permeability of the aquifer due to the main lithology of mucky clay slows down the groundwater flow, and strong evaporation and concentration on account of the shallow groundwater depth contributes significantly to iodine enrichment. [ABSTRACT FROM AUTHOR]

Groundwater contamination from non-engineered landfills has been extensively documented. However, there is a gap in extensive field research regarding whether engineered landfills can also contribute to groundwater contamination. We selected 62 engineered municipal landfills in Eastern China and collected both leachate samples from the landfills and groundwater samples from nearby wells. Through the analysis of inorganic solute indicators in both groundwater and leachate samples, we explored the impact of landfill leachate on the inorganic solute composition of groundwater. Our findings revealed that over half of the groundwater samples surrounding the landfill sites exceeded recommended drinking water limits for inorganic solutes. The correlation analysis demonstrates a significant relationship between Cl−, SO42−, Na+, and K+ levels in leachate and groundwater, highlighting the direct impact of landfill activities on groundwater quality. Moreover, specific characteristics of the landfill, such as its age, the total waste volume, and geographic location, were found to influence the inorganic solute composition in the groundwater. This effect was apparent in the positive correlations between the age of the landfill and NH3-N, Ca2+, and Mg2+ levels in groundwater, the total waste volume of the landfill and Ca2+ content in groundwater, and the latitude of the landfill and Cl− and HCO3− concentrations in groundwater. This work carries implications for assessing environmental risks associated with engineered landfills and enhancing landfill design, management, and monitoring practices. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the characteristics and formation mechanisms of groundwater in mining areas is essential for the effective prevention of coal mine water and the rational management of groundwater resources. The objective of this study was to examine the hydrogeochemical characteristics and evolution of Ordovician groundwater in the Zhuozishan coal mine, located in the northwest region of China. A total of 34 groundwater samples were collected for hydrogeochemical analyses and the investigation of their evolution processes, with the aid of a piper trilinear diagram, a Gibbs diagram, and an ion ratio diagram. The results indicate that the concentration of sodium (Na+), potassium (K+), bicarbonate ( HCO 3 − ), chloride (Cl−), sulphate ( SO 4 2 − ), total dissolved solids (TDS), and pH increases from the recharge area to the discharge area, whereas the concentration of calcium (Ca2+) and magnesium (Mg2+) decreases. The hydrogeochemical characteristics of the runoff from Zhuozishan to Gongdeer coalfield and further southward display a notable north–south directional change. The groundwater process is primarily controlled by rock weathering action and cation exchange, with Na+ and K+ deriving primarily from cation exchange and only to a minor extent from halite dissolution. In conclusion, the northern part of the coalfield is characterised by a geological structure that creates a retention area with groundwater, resulting in an unordered runoff process with a complex formation mechanism. The middle region is devoid of geological constraints that would alter the flow direction, thus simplifying the process of groundwater formation. In contrast, the southern area experiences an increase in strata depth and fault blocking, which creates a retention zone, thereby rendering the groundwater formation process more complex. This research contributes to the effective management of groundwater resources in this coalfield and other mining sites. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage 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.)

Karst groundwater is an important water resource for the production and lives of native residents in the Qingjiang River Basin, and even the only water source for some karst areas. It is necessary to determine the pollution sources and potential health risks of metal elements in karst groundwater. In this study, 10 metal elements (i.e., Al, Cu, Pb, Zn, Cr, Ni, Co, Cd, Mn and As) in 46 groups of karst groundwater samples were analyzed. Multivariate statistical analysis and positive matrix factorization model (PMF) were used to analyze the distribution characteristics, potential sources and contribution share of metal elements in karst groundwater in the Basin. The health risk assessment model was used to evaluate the potential health risks of metal elements exposed to adults and children through different intake pathways. The results showed that the qualitative analysis was consistent with the quantitative analysis of PMF. The qualitative results showed that Co, Cu, Pb, Mn and Al were mainly affected by primary geological processes, Ni and Cd were mainly affected by industrial activities, and As was mainly affected by agricultural activities. The quantitative results of the PMF model show that there are five main influencing factors in the study area. Factor 1 is mining activity, with an average contribution rate of 14.4%. Factor 2 is light industrial production activity, with an average contribution rate of 26.3%. Factor 3 is agricultural activity, with an average contribution rate of 19.3%. Factor 4 is road traffic action, with an average contribution rate of 17.8%. Factor 5 is primary geological action, with an average contribution rate of 22.2%. The total health risks exposed for residents through drinking pathway were higher than these through skin infiltration. The health risks of adults exposed through drinking pathway were lower than that of children, but the health risks of adults exposed through skin infiltration were higher than that of children. The main metal element causing carcinogenic health risk was identified as Cr, which should be paid more attention in the development and utilization of karst groundwater resources in the Basin. [ABSTRACT FROM AUTHOR]

Investigations have revealed the presence of microplastics in both soil and groundwater, but the migration characteristics from soil to groundwater remain incompletely understood. In this study, two sampling sections consisting of soil-groundwater-river water were established near Lianxi Bridge and Xilin Bridge along the Jiuxi River in Xiamen. A total of 22 soil samples, 36 groundwater samples, and 18 river water samples were collected. Microplastics were detected in all samples with an abundance range of 392–836 n/kg in soil (mean, 655 ± 177 n/kg), 0.58–2.48 n/L groundwater (mean, 1.23 ± 0.42 n/L), and 0.38–1.80 n/L in river water (mean, 0.86 ± 0.41 n/L). Flakes predominantly constituted the shape of microplastics found in soil, while fibers dominated those present in water. Black, yellow, and red were the dominant color types. Polyamide (PA) and polyethylene (PE) were the main components of microplastics within soils, whereas polyethylene terephthalate (PET), polypropylene (PP), and PA prevailed within water. Microplastic particle sizes ranged from 39 to 2498 μm in soils, mainly from 29 to 3394 μm in water. The upstream section displayed higher abundances of microplastic compared to the downstream, revealing the soil particles having an intercepting effect on microplastics. The distribution and migration of microplastics in soil and groundwater are affected by many factors, including natural and anthropogenic factors, such as soil depth, soil properties, pore structure, hydrodynamics, hydraulic connections between groundwater and surface water, the extensive utilization and disposal of plastics, irrational exploitation of groundwater, and morphology and types of microplastics. These research findings contribute to a better understanding of the pathways, migration capacity, and influencing factors associated with microplastic entry into groundwater, thereby providing valuable technical support for the development of strategies aimed at controlling microplastic pollution. [ABSTRACT FROM AUTHOR]

The present study focused on the distribution of uranium in groundwater samples collected from various sources in the Chikkaballapur district and its associated risk in humans. Seventy-five groundwater samples were collected during pre-monsoon and post-monsoon seasons and were analysed for uranium concentration along with different water quality parameters. The uranium concentration ranged from 0.23 to 285.23 µg/L in the pre-monsoon season and from 0.02 to 107.87 µg/L in the post-monsoon season. More than 90% of samples, except a few, were under the safe limits of 60 µg/L as directed by the Department of Atomic Energy (DAE) of India's Atomic Energy Regulatory Board (AERB). The study analysed physicochemical parameters like pH, total dissolved solids (TDS), nitrate, total hardness, phosphate, sulphate and fluoride in collected water samples. Out of all samples, few samples noted higher values of TDS, nitrate and fluoride. Their correlation along with uranium is detailed in the study. Owing to its slightly elevated content, an evaluation of the radiological and chemical hazards associated with uranium consumption was analysed. When the risk resulting from chemical toxicity was evaluated, relatively few samples had a hazard quotient (HQ) score higher than 1, which suggested that the people were vulnerable to chemical danger. This study also evaluates the dangers of elevated uranium levels in groundwater samples to the general public's health. It also acknowledges the importance of routinely evaluating and treating the drinking water sources in the region. [ABSTRACT FROM AUTHOR]

In the current groundwater contamination investigation study, sampling point allocation methods generally rely on modeling data analysis, which undoubtedly leads to increased sampling costs. Based on this lack of sampling data, the AHP-entropy weight method is improved and applied to construct a distribution model of groundwater pollution sampling points in a plant area, reduce the sampling scale and establish a new and optimised samplimg scheme. A chemical plant in Shenyang is selected for method validation and spatial interpolation analysis, and the following conclusions are drawn. (1) The new scheme can identify areas of contaminants and reduce sampling costs. (2) After reducing the sample size, the spatial distribution characteristics of each pollutant can still be clearly distinguished. (3) The interpolation-based predictions of some pollutants were improved, and the accuracy of the predictions of other pollutants was reduced within the permissible range. [ABSTRACT FROM AUTHOR]

The presence of uranium concentration in drinking water has been a serious issue for a long time and can accord elegance to a larger extent. The current study has assessed the amount of uranium present in groundwater samples collected from 35 locations in the Jammu and Kashmir districts of Ganderbal and Budgam. Two distinct methods have been used to analyze uranium: the LED fluorimeter and High-Resolution Inductively Coupled Plasma Mass Spectrometry (HR-ICPMS). Using the HR-ICPMS technique, the uranium concentration in water samples from the research area ranges from 0.40 to 4.88 µg l−1. Uranium concentration analyzed by two techniques of all water samples are well within the permissible limits of World Health Organization (WHO) and maximum contaminant level of United States Environmental Protection Agency (USEPA) 30 µg l−1. The estimated annual effective dose varies in the range of 6.7 × 10–7 to 8.1 × 10–6 µSv y−1. The radiological average cancer mortality and morbidity risks were found to be 4.02 × 10–6 and 6.22 × 10–6 respectively. Lifetime Average Daily Dose (LADD) has been calculated which lies in the range of 0.023–0.282 µg kg−1 day−1. The analyzed hazard quotient for all the samples has been found less than unity. Also, physico-chemical properties of water samples and their correlation with uranium content have been estimated. The present study forms the basis for the future health risk assessment of the Ganderbal and Budgam provinces of Jammu and Kashmir. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

Wastewater treatment plants (WWTPs) provide optimal conditions for the environmental spread of Legionella. As part of the Evaluation of Sanitary Risk Related to the Discharge of Wastewater to the Ground (SCA.Re.S) project, this study was conducted to evaluate the presence of Legionella in WWTP effluent and in groundwater samples collected from two wells located downstream from the plant. The samples were analyzed to determine the concentrations of Legionella spp using the standard culture-based method and molecular techniques, followed by genomic sequencing analysis. Legionella was detected only with the molecular methods (except in one sample of effluent positive for L. pneumophila serogroup 6), which showed viable Legionella pneumophila and L. non-pneumophila through the use of free DNA removal solution in both the effluent and groundwater, with concentrations that progressively decreased downstream from the plant. Viable L. pneumophila appeared to be slightly more concentrated in warm months. However, no significant differences (p ≥ 0.05) in concentrations between cold and warm months were observed. A genotypic analysis characterized the species present in the samples and found that uncultured Legionella spp, as yet undefined, constituted the prevalent species in all the samples (range 77.15–83.17%). WWTPs play an important role in the hygienic and sanitary quality of groundwater for different uses. The application of Legionella control systems during the purification of effluents is warranted to prevent possible outbreaks of legionellosis. [ABSTRACT FROM AUTHOR]

This research is to develop dictated metrics using a multi-proxy approach such as spatial–temporal analysis, statistical evaluation, and hydrogeochemical analysis. We have collected 45 groundwater samples located in the Tamirabarani river basin. To evaluate the aptness of developed metrics for agriculture and domestic needs and eleven years dataset has been analyzed and compared with national and international standards BIS, ICMAR, and WHO Monitoring and all the analysis results revealed that the concentration of calcium (Ca-1679 to 4937 mg/L; and Cl ions 236 to 1126 mg/L) and chloride ions was on the higher side in locations. These higher values may be attributed to the regional point sources as untreated water disposal and off-peak sources as agriculture practices. According to the results of the principal component analysis, the post-monsoon season accounted for an 84.2% variance. The major analyzed cations and anions have been observed in the following order: Na+ > Ca2+ > Mg2+ > K+ and Cl− > HCO3− > SO42− > NO3− respectively. Ca-Mg-HCO3, Mg-Ca–Cl, Na-C1, and infused waters have been discovered in the basin region, indicating that anion and cation dominance is not prevalent. This specifies that groundwater quality in this region is significantly degraded and suffers from extensive salinity due to the urban pollutants mixed with unprotected river sites. [ABSTRACT FROM AUTHOR]

Groundwater is an essential source of drinking as well as irrigation water. It has recently become a significant challenge to maintain good and safe drinking water for all living beings. The continuous supply of arsenic detected in groundwater poses a severe health problem and has adverse effects on humans and the ecosystem. Researchers also identified arsenic contamination globally across various regions. However, a few studies also identified that the groundwater of Patna, Saran, and Vaishali districts of Bihar is intoxicated by arsenic. To assess the toxic level of arsenic in groundwater, samples from various GPS-based pointed locations were collected from the study area using a GARMIN GPS device. The total concentration of arsenic in drinking water (mostly traces of arsenic, level of μg L−1 or less) can be detected only by sophisticated analytical techniques such as ICP-MS, GF-AAS, and HG-AAS. The standard procedures were followed to determine quality attributes in groundwater. Arsenic contamination persists in most areas and exceeds the permissible limits prescribed by the World Health Organization (WHO), negatively impacting the health of more than 10 million people in the state. The 90.47% and 85.71% groundwater samples of the study area exceeded the permissible limit of the WHO (0.01 mg L−1) and Bureau of Indian Standards (BIS (0.05 mg L−1), respectively. The analyzed data was obtained, and variability was noticed in total arsenic concentrations ranging from 0.002 to 7.801 mg L−1, with a mean value of 0.87 mg L−1. Similarly, the water quality attribute like total dissolved solids were identified in 14.28% of samples, which crossed 201 to 1026 mg L−1, with a mean value of 375.33 mg L−1. [ABSTRACT FROM AUTHOR]

This study seeks to assess the hydrogeochemical characteristics of groundwater in the southern part of Thal Desert of Pakistan. The primary focus lies in identifying potential sources of contamination and evaluating their impact on groundwater and the ecosystem. Groundwater samples were collected from diverse sources including shallow hand pumps, tubewells, and dug wells, with depths ranging from 11 to 28 m. A comprehensive analysis was performed to scrutinize the physical, chemical, and microbial attributes of the samples. Utilizing visual aids like the Piper, Durov, and Gibbs diagrams, as well as Pearson correlation, scatter plots, Schoeller diagrams, and pie charts, the study evaluated the groundwater quality and its suitability for consumption. Results indicate that mineral infiltration from rainfall, domestic waste, and industrial effluents significantly affects groundwater quality, leading to widespread salinity. Weathering processes and ion exchange were identified as key factors contributing to elevate levels of bicarbonates, sodium, magnesium, and chloride ions. Employing the Water Quality Index (WQI) on 40 groundwater samples, findings reveal that 52.5% of samples demonstrated poor to not suitable quality, with 27.5% categorized as poor, 2.5% as very poor, and 22.5% not suitable consumption. Conversely, 47.5% of samples showcased good to excellent quality, with 25% rated as good and 22.5% as excellent. These findings provide valuable insights for hydrogeologists to develop appropriate strategies for water treatment and address any concerns related to groundwater quality. [ABSTRACT FROM AUTHOR]

Reduced-scale CO2 release experiments in shallow aquifers serve as crucial monitoring strategies for detecting unintended CO2 leakage into potable aquifers within Carbon Capture and Storage (CCS) projects. Understanding site-specific geological, hydrogeological, and climatic features is essential. However, accurately tracing changes in groundwater quality due to this process and using hydrochemical parameters for CO2 leakage diagnosis require establishing a solid, seasonally relevant baseline to avoid misinterpretation. This study focuses on detailing the geological, hydrogeological, and geophysical characteristics of the TECNOPUC-Viamão CO2 controlled-release experimental site in Rio Grande do Sul, Brazil. It presents a comprehensive three-year investigation into the seasonal natural background hydrochemistry. Field characterization involved recognition boreholes, in-situ infiltration and Slug Tests, topographic surveys, DC resistivity measurements, and groundwater sampling campaigns for physicochemical, major, minor, trace elements, and δ¹³C-DIC evaluation. Results indicate the area comprises a granite-derived multilayer phreatic aquifer with two distinct hydrostratigraphic units (St and Aa). These units differ in lithological composition, hydraulic conductivities (St: 10− 4 m/s, Aa: 10− 8 m/s), apparent resistivities, and physicochemical and hydrochemical compositions. The St unit shows slightly neutral pH, higher temperature, EC, ORP, DO, Ca, Mg, K, Fe, Mn, Sr, B, HCO3−, and DIC concentrations, with δ¹³C-DIC between − 3 to -8‰. Conversely, the Aa unit displays slightly acidic pH, lower temperature, EC, ORP, higher DO fluctuation, Na, SO42−, Cl−, NO3−, Zn, Al, Ni concentrations, lower HCO3−, DIC levels, with δ¹³C-DIC ranging between − 6 to -11‰. Additionally, seasonal monitoring campaign revealed that there is a clear temperature-related influence on K, Na and trace elements (Fe, Ba, Mn, Al, B, and Zn) behavior (but not in Ca, Mg, Sr and Ni), which could impact further interpretation of the results during the upcoming CO2 injection phase, and that the Control Charts can confidently serve as a valuable tool in understanding the inherent natural hydrochemical trends. [ABSTRACT FROM AUTHOR]