Search Results (285)

Contamination of drinking water by potentially toxic elements (PTEs) remains a critical public-health concern in Uganda. This systematic review compiled and harmonized quantitative concentrations (mg/L) for key PTEs, lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), mercury (Hg), copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), manganese (Mn), and iron (Fe), across various potable and informal water sources used for drinking, including municipal tap water, boreholes, protected and unprotected springs, wells, rainwater, packaged drinking water, rivers, lakes, and wetlands. A comprehensive search of different databases and key institutional repositories yielded 715 records; after screening and eligibility assessment, 161 studies met the inclusion criteria, and were retained for final synthesis. Reported PTE concentrations frequently exceeded WHO and UNBS drinking water guidelines, with Pb up to 8.2 mg/L, Cd up to 1.4 mg/L, As up to 25.2 mg/L, Cr up to 148 mg/L, Fe up to 67.3 mg/L, and Mn up to 3.75 mg/L, particularly in high-risk zones such as Rwakaiha Wetland, Kasese mining affected catchments, and Kampala’s urban springs and drainage corridors. These hotspots are largely influenced by mining activities, industrial discharges, agricultural runoff, and corrosion of aging water distribution infrastructure, while natural geological conditions contribute to elevated background Fe and Mn in several regions. The review highlights associated health implications, including neurological damage, renal impairment, and cancer risks from chronic exposure, and identifies gaps in regulatory enforcement and routine monitoring. It concludes with practical recommendations, including stricter effluent control, expansion of low-cost adsorption and filtration options at household and community level, and targeted upgrades to water-treatment and distribution systems to promote safe-water access and support Uganda’s progress toward Sustainable Development Goal 6. Full article

Eutrophication of water bodies and the bloom of toxin-producing cyanoprokaryotes raise health concerns. Various cyanoprokaryotes species, including Microcystis, Raphidiopsis, Nodularia, and Chrysosporum, release toxins into the aquatic environment, which can reach concentrations toxic to humans and animals. Rising temperatures and human activities are primary drivers behind the increasing frequency of toxic cyanobacterial blooms. The Word Health Organization (WHO) has established provisional guideline values for cyanotoxins in drinking water and water used for other purposes in daily human activities, and has published guidance for identifying hazards and managing risks posed by cyanobacteria and their toxins. There are currently no acceptable limit values for cyanotoxins. To address monitoring needs, contemporary strategies now incorporate molecular genetics, immunoassays, biochemical profiling, and emerging machine-learning frameworks. This paper reviews current early detection methods for harmful cyanobacterial blooms, highlighting their practical advantages and drawbacks. Full article

Sustainable groundwater management is critical in semi-arid coastal regions, where municipal landfills pose a severe threat to aquifer integrity and long-term water security. However, there is still a lack of seasonally resolved hydrogeochemical monitoring around newly established landfills, particularly in rapidly urbanizing Mediterranean settings. This study assesses the hydrogeochemical impact of the newly operational Tangier Landfill and Recovery Center on local groundwater resources to inform sustainable remediation strategies. A combined approach was applied to samples collected in dry and wet seasons, using Piper and Stiff diagrams to trace facies evolution together with a dual-index assessment based on the Canadian (CCME-WQI) and Weighted Arithmetic (WAWQI) Water Quality Indices. Results show that upgradient waters remain of Good–Excellent quality and are dominated by Ca–HCO₃ facies, whereas downgradient wells display extreme mineralization, with EC up to 15,480 µS/cm and Cl⁻ and SO₄²⁻ exceeding 1834 and 2114 mg/L, respectively. At hotspot sites P4 and P8, As reaches 0.065 mg/L and Cd 0.006 mg/L, far above the WHO drinking-water guidelines. While the CCME-WQI captures the general salinity-driven degradation pattern, the WAWQI pinpoints these acute toxicity zones as Very poor–Unsuitable. The study demonstrates that rainfall intensifies toxicity through a seasonal “Piston Effect” that mobilizes stored contaminants rather than diluting them, underscoring the need for seasonally adaptive monitoring to ensure the environmental sustainability of landfill-adjacent aquifers. Full article

Groundwater is the main water source for irrigated agriculture, accounting for an increasing share of the domestic supply in the hyper-arid district of La Yarada Los Palos (Tacna, Peru); however, at the sector scale, concerns about arsenic, boron and salinity remain poorly quantified. Arsenic and boron were selected as target contaminants because of their naturally elevated concentrations associated with coastal and volcanic hydrogeological settings, and their well-documented implications for human health and irrigation suitability. This study reports a 12-month monitoring program (September 2024–August 2025) in three irrigated sectors, in which wells were sampled monthly and analyzed by inductively coupled plasma–mass spectrometry (ICP-MS) for total arsenic, boron, lithium and sodium, along with electrical conductivity, pH, temperature and total dissolved solids. The sector–month total arsenic means ranged from 0.0089 to 0.0143 mg L⁻¹, with 33 of 36 exceeding the 0.010 mg L⁻¹ drinking water benchmark recommended by the World Health Organization (WHO). Total boron ranged from 1.11 to 2.76 mg L⁻¹, meaning that all observations were above the 0.5 mg L⁻¹ irrigation guideline for agricultural use proposed by the United Nations Food and Agriculture Organization (FAO). A marked salinity gradient was observed from the inland Sector 1-BH (median Na ≈ 77 mg L⁻¹; EC ≈ 1.2 mS cm⁻¹) to the coastal Sector 3-LC (median Na ≈ 251 mg L⁻¹; EC ≈ 3.3 mS cm⁻¹), with Sector 2-FS showing intermediate salinity but the highest median boron and lithium levels. Spearman rank correlations indicate that sodium, electrical conductivity and total dissolved solids define the main salinity axis, whereas arsenic is only moderately associated with boron and lithium and is not a simple function of bulk salinity. Taken together, these results show that groundwater from the monitored wells is not safe for drinking without treatment and is subject to at least moderate boron-related irrigation restrictions. The sector-resolved dataset provides a quantitative baseline for La Yarada Los Palos and a foundation for future work integrating expanded monitoring, health-risk metrics and management scenarios for arsenic, boron and salinity in hyper-arid coastal aquifers. Full article

Adequate hydration is essential for health, yet the contribution of water from food (WFF) to total water intake (TWI) and its determinants remain unclear in China. This study quantified WFF and explored factors influencing its variation among young Chinese adults. A multicentre cross-sectional survey was conducted in May–June 2023 among 947 healthy adults aged 18–25 years from seven regions of China. WFF was measured using three-day duplicate food portions, and drinking fluid intake was recorded with a validated 24 h diary. Sociodemographic, dietary, behavioral, and psychological data were collected using standardized instruments. Multivariable linear regression, stratified by sex and age, examined associations with WFF and its proportion of TWI. On average, WFF accounted for 38.0% of TWI, with regional variation from 33.5% in southern China to 44.3% in eastern China. Higher daily intake of energy, salt, and carbohydrate intakes were each positively associated with greater WFF, while carbohydrate intake seemed to betas the strongest predictor of a higher proportion of WFF. Younger age and elevated anxiety showed modest independent associations. These findings indicate that WFF contributes substantially to hydration in Chinese young adults, primarily driven by dietary composition. Recognizing WFF in hydration guidelines could improve population assessments and inform evidence-based nutrition strategies in China and other high-moisture diet regions. Full article

Chemical contaminants in drinking water represent a widespread threat to human health, making water quality monitoring an essential mitigation measure. This study aimed to assess the quality of drinking water by conducting comprehensive multi-year seasonal monitoring at seven distribution points in central Romania, determining the spatial and temporal trends of relevant physical parameters (pH and electrical conductivity) and chemical contaminants (NO₂, NO₃, NH₄, Cl, and SO₄). The pollution degree was evaluated using the pollution index and the overall pollution assessment index. The principal component analysis attributed over 60% of water quality variance to NO₂, NO₃, and NH₄ pollution, linked to incomplete nitrification or external loading, such as agricultural practices. Additionally, a human health risk assessment was performed according to U.S. EPA guidelines, calculating the chronic daily intake, hazard quotient, and hazard index for nitrogen compounds via oral and dermal exposure pathways for both adults and children. The results showed significant seasonal fluctuations in nitrogen compounds and electrical conductivity. The pollution indices classified the water bodies across a spectrum from “light” to “significant” pollution degrees. The health risk assessment revealed that NO₃ was the primary risk driver, with hazard index values exceeding the threshold of one in specific locations and seasons, indicating potential adverse health effects, particularly for children. Full article

Ensuring access to safe drinking water is a fundamental public health priority, yet the growing diversity of contaminants demands more human-relevant toxicity assessment frameworks. Conventional models based on immortalized cell lines or sentinel species, while informative, lack the tissue complexity and inter-individual variability required to capture realistic human responses. Organoids, three-dimensional epithelial structures derived from adult or pluripotent stem cells, retain the genomic, histological, and functional characteristics of their original tissue, enabling assessment of contaminant-induced toxicity, short-term peak exposures, and inter-donor variability within a single system. This study examined whether current international drinking water guidelines remain protective or if recent organoid-based findings reveal toxicity at differing concentrations. Comparative synthesis indicates that per- and polyfluoroalkyl substances (PFAS) often display organoid toxicity at concentrations above current thresholds, suggesting conservative guidelines, whereas most metals are properly regulated. However, some metals exhibit toxicity at concentrations that include levels below guideline values, highlighting the need for further investigation. Emerging contaminants, including pesticides, nanoparticles, microplastics, and endocrine disruptors, induce adverse effects at environmentally relevant concentrations, despite limited or absent regulatory limits. Integrating organoid-based toxicology with high-frequency monitoring and dynamic exposure modeling could refine water quality guidelines and support adaptive regulatory frameworks that better reflect real-world exposure patterns and human diversity. Full article

Nickel ions (Ni²⁺) are persistent heavy metal pollutants that pose significant risks to human health due to their toxicity. Conventional treatment technologies, while effective, are often costly, energy-intensive, and limited in removing emerging pollutants. In this study, we report an eco-friendly, fluorescence-based sensing platform using carbon nanostructures (CNs) synthesized from coffee waste via pyrolysis at 600 °C. The CNs were characterized by Fourier transform infrared (FTIR) spectroscopy and evaluated for their fluorescence response toward Ni²⁺, Co²⁺, Cu²⁺, and Cd²⁺ ions. Distinct ion-specific behaviors were observed, with Ni²⁺ inducing the strongest fluorescence quenching. Sensitivity studies revealed reliable detection across 10⁻⁸–10⁻³ M, with a detection limit of 10⁻⁴ M (≈5.9 mg/L). Fluorescence stability was maintained for up to six hours, with one hour identified as the optimal detection window. Performance in real water samples highlighted consistent responses in mineral water, reflecting reliable sensing capability in a realistic aqueous matrix. While the current detection limit is above the World Health Organization guideline for drinking water, the CNs show promise for monitoring Ni²⁺ in contaminated or industrial effluents. Overall, this work demonstrates that coffee waste-derived CNs provide a cost-effective, sustainable approach to heavy metal sensing, linking waste valorization with environmental monitoring. Full article

Intermittent water supply is common in Palestine, prompting schools to rely on on-site water storage systems, including underground and roof tanks. Prolonged and uncontrolled water storage leads to quality degradation, especially with free residual chlorine (FRC) depletion. Hence, this poses health risks to students and staff. This pilot (field) study evaluated the effectiveness of booster chlorination under the current storage conditions to optimize and improve the existing chlorination process. Four schools were selected based on the type of water storage systems (two with underground tanks, two with roof tanks) and building age. Booster chlorination was applied at two chlorine doses (0.5 mg/L and 1 mg/L). FRC was monitored until levels dropped below 0.05 mg/L. Results show that the currently applied chlorine dose (0.5 mg/L) is insufficient to reach the minimum national FRC standard (0.2 mg/L) after 30 min. In contrast, a 1 mg/L chlorine dose is more effective in maintaining the minimum FRC concentration limit for a longer time. In addition, manual mixing is ineffective in large underground tanks, while it is effective in roof tanks. This study urges the need to revise the national chlorination guidelines and to adjust chlorination practices to ensure safe drinking water in schools. Full article

Freshwater quality criteria (FWQC) are essential scientific thresholds established to protect human health and aquatic ecosystems, serving as the foundation for water quality standards, environmental risk management, and pollution control. The latest research advancements were summarized, including the screening of priority pollutants for FWQC and the theory and methodology for environmental criteria in China in the last decade. The potential work has been meticulously analyzed and discussed concerning FWQC to be conducted in the short-term future. The possible prioritized list of pollutants for FWQC should be concerned with including nine categories of heavy metal ions, three categories of non-metal ions, and five categories of organic compounds in the short-term future research. The guidelines for deriving FWQC for the protection of human health for organoleptic effects and for sediment need to be modified and emphasized to ensure the safety of drinking water sources, address issues related to black and odorous surface water, and protect the biodiversity of benthic organisms. Toxicity data, water quality parameters, exposure data, and the geographical distribution of freshwater species should be systematically collected to support the development of FWQC in China. The potential applications of FWQC were also explored in the evaluation and formulation of WQS, ecological risk assessments, and the management of environmental emergencies and damage assessments to support environmental protection and management in China. Full article

The central objective of this study was to investigate metals accumulating in water at the bottom of roof-harvested drinking water tanks in rural inland NSW, located from 220 km west to 420 km northwest of Sydney. Two of three study areas contained mining operations. The Narrabri study area contained five coal mines, the Cadia study area a large gold and copper mine. A third region (Mendooran) had no mines. In this study, turbidity, pH, salinity and the total concentration of 15 metals were measured in water tank samples. Four metals (cadmium, lead, nickel and manganese) and arsenic from the bottom of tanks often exceeded Australian Drinking Water Guidelines. Of drinking water samples, 90% exceeded lead guidelines (<10 µg L⁻¹), with 54% exceeding by 100 times and 3.6% of samples exceeding lead guidelines by 1000 times. Contamination was generally greater in Cadia area tanks. It is likely that metal-enriched mine particulate emissions contribute through fallout onto roofs used to harvest drinking water. Improved environmental monitoring and governance to address metal-contaminated dust emissions from mines and improved information on fallout plumes are needed. Action is also needed to encourage regular cleaning of drinking water tanks. Full article

Climate change affects both the quantity and quality of water resources, amplifying the water crisis, slowing progress toward achieving the Sustainable Development Goals (SDGs), and contributing to the needs of future generations. To address these challenges, this study presents an interdisciplinary synthesis of the literature on the subject, highlighting the impact of climate change on water resources (surface water and groundwater). The escalating global demand for water, driven by factors such as population growth, urbanization, and industrial development, is placing significant pressure on water resources. This situation needs sustainable management solutions to mitigate the environmental impacts associated with increased water consumption and climate change. The methodology included bibliometric analysis using VOSviewer version 1.6.19, a software tool for constructing and visualizing bibliometric networks, and systematic analysis according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. 155 records were used in this review from a total number of 1344 documents searched in Science Direct, Scopus and Google Scholar databases. The results indicate that research on the consequences of climate change on water quality remains in its infancy. This study highlights the effects of climate change on water quality indicators, including physicochemical, microbiological, and micropollutants, as well as the implications for human health and water supply infrastructure. Climatic factors, such as rising temperatures and changing precipitation patterns, are particularly important because they control processes fundamental to sustaining life on the planet. The main conclusions are that climate change accelerates the degradation of drinking water quality and amplifies public health risks. These findings highlight the need for rigorous assessments and the development of integrated adaptation strategies involving collaboration among water operators, decision-makers, the scientific community, and climate change specialists. Full article

People are exposed to pesticides daily through food, drinking water, and the environment, both in urban and rural settings. These chemicals, while offering economic and agricultural benefits through pest control and increased productivity, may pose a growing risk to human health and ecosystem biodiversity. While the European regulatory framework offers a robust foundation for risk assessment, significant limitations persist, especially in addressing cumulative exposure, low-dose effects, and chemical mixtures. This review focuses on selected scientific and regulatory challenges by reviewing recent European Food Safety Authority (EFSA) conclusions, Organization for Economic Co-operation and Development (OECD) test guidelines updates, and current European legislative approaches. Particular attention is given to the regulation of endocrine-disrupting and reprotoxic substances, highlighting progress and remaining gaps in implementation. A brief mention will also be made of immuno-toxic substances, for which no specific hazard class has yet been established. Building on official reports and peer-reviewed literature, this review provides a structured evaluation of the scientific and regulatory landscape, including underexplored issues like the transition to animal-free toxicology and integration of biomonitoring with health data. The goal is to propose realistic, evidence-based improvements to current frameworks using integrated, interdisciplinary approaches that connect toxicology, policy, and implementation science. A shift to a holistic, systems-based, and precautionary paradigm is vital to address emerging challenges and ensure strong protection of health and environment, as well as supporting the needs of the agricultural sector. Full article

Groundwater quality is a key factor and a critical determinant of public health, agriculture, and socio-economic development, particularly in regions where private wells and mineral springs constitute the primary water sources. This study presents an integrated hydrochemical, radiological, and toxicological assessment of groundwater in the Sângeorz-Băi area, Romania, a spa region where mineral waters hold both therapeutic and economic significance. Samples from mineral springs, the municipal supply system, and private wells were analyzed to evaluate compliance with national and international standards and to assess their suitability for drinking, therapeutic, and agricultural purposes. The results reveal distinct hydrochemical contrasts between sources. Mineral springs are characterized by elevated salinity, hardness, and Na–HCO₃ facies, whereas the municipal network and private wells are dominated by Ca–HCO₃ facies. More than half of the private wells exceeded permissible limits for NO₃⁻, NO₂⁻, NH₄⁺, Pb, and Fe, with one well posing a significant nitrite-related health risk. Trace metal analysis indicated localized enrichment in Cu, Fe, and Pb. Radon and radium activities generally complied with regulations, although radium occasionally exceeded the more stringent WHO guidelines. Seasonal variation was minimal, reflecting stable groundwater chemistry. Health risk and irrigation assessments suggest that municipal supply water is largely safe for consumption, while private wells require targeted monitoring and mitigation. Despite elevated Na⁺ and Cl⁻, mineral springs retain therapeutic value under controlled use. This study provides a replicable framework for groundwater quality assessment in spa regions and offers critical insights for public health protection, sustainable tourism, and agricultural resilience. Full article

Nepal is currently facing critical water quality challenges due to urbanization, water management and governance issues, as well as natural disasters. This has resulted in the presence of harmful contaminants (e.g., pathogens, nitrates, arsenic) across multiple water sources, subsequently leading to waterborne disease risks (e.g., cholera and typhoid). In response to these environmental and public health concerns, we conducted a scoping review to assess microbial and chemical contaminants in drinking and irrigation water in Nepal, as well as their potential impacts on public health. Following the JBI Manual for Evidence Synthesis and the PRISMA-SCR guidelines, we systematically searched for peer-reviewed literature on Nepal’s water quality in seven databases. Of 3666 unique records screened using predefined inclusion criteria, 140 met our criteria. The studies encompassed a variety of methodological designs, with the majority focusing on water sources in the Bagmati province. Bacteria and arsenic emerged as the most prevalent contaminants. Additionally, diseases such as arsenicosis and typhoid remain widespread and may be linked to contaminated water sources. The review identified key gaps in Nepal’s water quality management, including limited geographic research coverage, inconsistent testing protocols, weak regulatory enforcement, and a lack of integration of water quality with public health planning. Our findings underscore the urgent need for effective surveillance systems and a robust regulatory framework to promptly respond to water contamination events in Nepal. Full article