Search Results (124)

Background: Access to safe drinking water remains a critical public health concern in rural Ghana, particularly in climatically vulnerable and underserved settings. This study assessed the microbiological and chemical quality of drinking water and evaluated nitrate-related health risks in the North Gonja and North-East Gonja Districts of the Savannah Region. Methods: A cross-sectional study was conducted between January and March 2025. A total of 460 water samples were collected from groundwater sources and household storage containers. Microbial analyses targeted total coliforms and Escherichia coli. Physicochemical and chemical parameters included nitrate-nitrogen, pH, residual chlorine, major ions, and trace metals. Data was analyzed using descriptive statistics, chi-square tests, spatial interpolation, and non-carcinogenic health risk assessment based on the hazard quotient (HQ) approach. Results: Widespread microbial contamination was observed, with 91.5% of household water samples positive for total coliforms and 46.6% for E. coli. Contamination of source water was significantly higher in North Gonja than in North-East Gonja. Overall, 49.1% (n = 55) of groundwater sources exceeded the World Health Organization guideline value for nitrate-nitrogen, with exceedances predominantly occurring in North Gonja. Additionally, 67.0% (n = 75) of samples were outside the acceptable pH range (6.5–8.5), including 74 samples below 6.5 and one above 8.5. Residual chlorine was not detected in any of the samples. Health risk assessment indicated potential non-carcinogenic risks associated with nitrate exposure, particularly among infants and children. Conclusions: The study demonstrates significant microbial contamination and nitrate-related health risks in the study area, particularly in North Gonja. Interventions such as improved source protection, routine water quality monitoring, chlorination, household water treatment, and implementation of Water Safety Plans are recommended to enhance drinking water safety and reduce associated public health risks. Full article

Small decentralized water supply systems are often sensitive to local pollution and require a clear understanding of recharge conditions and the hydrodynamics within the water resource catchment. This study develops a conceptual hydrogeological model for the Šmarna Gora area based on geological mapping, long-term monitoring of chemical parameters, and stable isotope analyses (δ¹⁸O, δ²H) of precipitation and groundwater. The study was initiated in response to rising pollutant concentrations in the drinking water. Estimates of transit time (TT) and mean residence time (MRT) were used to characterize recharge, mixing processes, and differences between the SG and ZAVRH wells, the existing and alternative water supply wells. Isotope data show that the aquifer is predominantly recharged during colder periods and that Mediterranean air masses have become an increasingly important source of precipitation, suggesting a shift in precipitation patterns. The results indicate that SG has longer TT (6–8 months) and MRT (up to 1–2 years). In contrast, ZAVRH shows shorter TT and MRT (4–6 months), and lower pollutant concentrations. The hydrogeological regime in the catchment of the ZAVRH well is characterized by a dynamic, fast-flowing system with limited storage and more intensive dilution of contaminants by infiltrating water, whereas the catchment of the SG well functions as a deeper and more buffered aquifer with prolonged groundwater residence and a more direct hydraulic linkage to the contaminant source. The findings distinguish two hydrogeological regimes and provide a basis for planning water supply solutions and protection measures. Full article

Sustainable air quality governance requires robust monitoring and updated air quality management plans (AQMPs) to translate legislation into meaningful environmental and health protection. The Highveld Priority Area (HPA), which was declared South Africa’s second National Air Pollution Priority Area in 2007, includes the Ekurhuleni Metropolitan Municipality (EMM), where AQMPs are outdated and long-term chemical characterization data remain limited. This study provides baseline evidence to support AQMP revision by characterizing PM_2.5 mass concentrations and chemical composition in a residential area of Kempton Park within the EMM and HPA. A total of 57 24 h PM_2.5 samples were collected every sixth day from May 2021 to April 2022. Concentrations ranged from 0.9 to 32 µg/m³ (annual mean 10 µg/m³), exceeding the WHO annual guideline (5 µg/m³) but remaining below the South African standard (20 µg/m³). The daily WHO guideline (15 µg/m³) was exceeded on 13 days. PM_2.5, black carbon and organic carbon peaked during winter and spring, consistent with enhanced atmospheric stability and combustion emissions, while elements Br, Fe, K, S, Si and Sr exhibited seasonal variability. Principal component analysis and enrichment factor assessment distinguished crustal sources (Si, Ca, Fe, Ti) from enriched anthropogenic elements (S, Zn, Br, U), indicating contributions from combustion, industrial activities and mining. Correlation patterns and 72 h back-trajectory analysis further demonstrated shared sources and significant regional transport influences. These findings highlight the combined role of local emissions, meteorology and long-range transport, providing locally relevant evidence to inform sustainable air quality management within the EMM and HPA. Full article

Air pollution associated with public transport systems constitutes a critical yet highly heterogeneous component of urban exposure and represents an important challenge for sustainable urban mobility and environmental health governance. Commuters and transport workers are frequently subjected to pollutant concentrations that exceed those reported by ambient background monitoring networks. This review provides a comprehensive synthesis of the global scientific literature on air quality in public transport microenvironments—including buses, bus stops, terminals, and underground stations—through a multidimensional analytical framework that considers climatic classification, socio-economic context, meteorological drivers, transport microenvironment typology, sampling strategies, analytical techniques, and exposure metrics. A large body of peer-reviewed studies published worldwide was examined to identify dominant patterns, methodological trends, and persistent knowledge gaps. Across regions, the evidence consistently reports elevated concentrations of particulate matter (PM_2.5, PM₁₀, and ultrafine particles) and traffic-related gaseous pollutants, particularly within confined or poorly ventilated environments and during peak traffic periods. Marked geographical, climatic, and socio-economic imbalances are evident, with most studies conducted in temperate and tropical climates and in countries with very high or high Human Development Index, whereas arid, continental, and low-HDI regions remain substantially underrepresented. From a methodological perspective, the literature is dominated by short- to intermediate-term monitoring campaigns relying on active sampling, mobile measurements, and increasingly calibrated low-cost sensors, while long-term stationary observations and standardized integrative monitoring frameworks remain scarce. Although advanced analytical approaches—such as chemical characterization, environmental magnetism, receptor modeling, computational fluid dynamics, and inhaled dose assessment—are increasingly applied, their systematic integration remains limited. Overall, this review reveals persistent methodological, geographical, and conceptual gaps and highlights the urgent need for standardized, interdisciplinary, and long-term monitoring strategies to improve exposure assessment and support evidence-based mitigation policies and sustainable urban transport planning aimed at reducing health risks associated with public transport-related air pollution. Full article

Thoracic malignancies are uniquely positioned for the integration of emerging technologies such as artificial intelligence (AI), which have the potential to advance precision oncology across the cancer care continuum. In cancer screening, AI has emerged as a promising strategy to enhance diagnostic accuracy, efficiency, and scalability. Deep learning applied to pathology (pathomics) and imaging (radiomics) has enabled the development of novel, noninvasive tools capable of predicting histologic and molecular features that may correlate with treatment response or toxicity. In drug discovery, computational approaches can analyze large-scale genomic, chemical, and clinical datasets to accelerate target identification and match candidate compounds to available targets; this may be particularly useful in the context of resistance to targeted therapy. AI tools may also support treatment planning for radiation and surgery, guide systemic therapy selection, and facilitate continuous monitoring for early identification of treatment resistance or toxicity. As these technologies are integrated into clinical workflows, careful attention to ethical, regulatory, and clinical governance frameworks will be essential to ensure equitable implementation and bias mitigation. Maintaining human oversight and a human-centered approach remain critical, as complex treatment decisions and sensitive patient interactions are central to the care of patients with thoracic malignancies. Full article

Enhanced rock weathering (ERW) is a promising carbon dioxide removal strategy that accelerates silicate mineral dissolution to generate alkalinity and sequester carbon in soils and aquatic systems. The frequency and severity of fires are increasing globally, and fire-prone regions such as agricultural lands, forests, and grasslands overlap substantially with potential ERW deployment areas. However, fire–ERW interactions remain unexamined. This perspective synthesizes the literature on fire effects on soil properties to develop a conceptual framework for predicting fire impacts on ERW performance. An assessment of the available literature reveals that the effects of fire on soil pH and inorganic carbon are nonlinear with respect to severity, complicating both dissolution kinetics and carbon verification. Base cation pulses from ash are temporary and subject to rapid export. Fire-induced soil water repellency and erosion may dominate chemical effects in controlling ERW material fate, particularly during the first year post-fire. Pyrogenic carbon and thermally altered minerals create novel soil–rock interactions with unknown consequences for weathering rates. The authors concluded that fire history must be incorporated as a covariate in ERW deployment planning and monitoring, reporting, and verification design. Full article

In agriculture, the use of per- and polyfluoroalkyl substances (PFASs) as active substances in pesticides has increased over recent decades due to their chemical stability, their ability to alter cell membrane permeability, and their capacity to bind to target proteins. However, their intentional application to agricultural soils has led to progressive environmental accumulation. Their high persistence, mobility, and bioaccumulation potential, combined with documented toxicological effects, raise concerns for aquatic organisms and ecosystems. Monitoring surface and groundwater is essential to assess PFAS contamination. Data from the Italian monitoring plan show widespread contamination, despite the existing European regulatory framework designed to safeguard ecosystems and public health. The contamination is likely underestimated because monitoring programs currently target only a limited number of substances and PFAS metabolites and co-formulants are not included. Approximately 46 PFASs have been identified as active ingredients in pesticides, 29 of which are still authorized within the European Union, posing challenges for drinking water production and ecosystem protection. Existing regulatory regimes also differ in their evaluation procedures, which may lead to inconsistent conclusions regarding PFAS applications. Within the framework of the European “One Substance One Assessment” (OSOA) approach aimed at to ensuring the protection of human health and natural resources, this paper examines the properties of PFASs used as active substances in pesticides, their regulatory status, and their monitoring in Italy, highlighting the regulatory inconsistencies that result in the differential treatment of these substances compared with PFASs used in other sectors. Full article

Groundwater is a critical resource in the arid Chili River sub-basin (3246 km²) in Arequipa, southern Peru, yet the aquifer systems, their recharge mechanisms, and chemical evolution remain poorly characterized. This study integrates hydrogeological mapping, major-ion hydrochemistry (31 samples from springs and wells), and stable-isotope tracing (δ¹⁸O and δ²H, 11 sources) to delineate aquifer types, groundwater flow systems, and recharge dynamics across an elevation gradient of 2000–4000 m a.s.l. Three principal aquifer groups were identified: unconsolidated porous aquifers beneath the Arequipa urban area, fracture-controlled volcanic aquifers associated with the Chachani, Misti, and Pichupichu volcanic complexes, and sedimentary fractured aquifers of the Yura Group. Piper and Stiff diagrams reveal a chemical evolution from calcium-bicarbonate waters at high elevations to sodium-chloride waters in the lowlands, while scatter-plot analysis distinguishes local, intermediate, and regional flow systems. Elevated boron concentrations linked to borate deposits on Pichupichu volcano pose a potential health risk in supply springs such as La Bedoya. Isotopic signatures confirm that wells are recharged predominantly by high-altitude rainfall (>4000 m a.s.l.), whereas springs integrate water from multiple elevations through fractured volcanic formations. These findings provide a scientific basis for recharge-zone protection, abstraction planning, and water-quality monitoring to sustain groundwater supply under increasing urbanization and climatic variability. Full article

This study aimed to quantify and assess the spatial distribution of ²³⁸U, ²³²Th, and ⁴⁰K in the soils of the Espora Hydroelectric Power Plant (Espora HPP) and Queixada Small Hydroelectric Power Plant (Queixada SHPP) watershed (model hydraulic development areas) and their relationship with the geological, chemical, physical, and biological aspects of the soil. The study areas are located in the Corrente River drainage basin, in the southwestern portion of the state of Goiás, Brazil. Radionuclides were quantified using a PGIS-2 portable gamma spectrometer, with measurements taken at 21 sampling points. Soil samples were collected from the surface layer (0–20 cm) for particle-size and chemical analyses. The results indicated that the average radionuclide contents in the soils were 64.49 Bq/kg for ⁴⁰K, 45.44 Bq/kg for ²³⁸U, and 4.53 Bq/kg for ²³²Th. When comparing these values with the global average established by UNSCEAR, it was observed that ²³²Th and ⁴⁰K concentrations were below the global reference, whereas ²³⁸U concentration exceeded the world average of 33 Bq/kg. Particle-size characterization revealed significant variability in soil texture, with sand content ranging from 51.46 to 90.91%, clay content from 7.45 to 30.64%, and silt content from 1.64 to 17.90%. Organic matter content had an average of 10.09 g/kg, while soil pH ranged from 4.67 to 6.54. The results of this study have demonstrated the relevance of integrating radiometric and geochemical data for assessing environmental safety in hydroelectric development areas. The approach adopted can support monitoring programs and decision-making processes related to soil management and land-use planning in regions influenced by hydraulic infrastructures. Full article

Heavy metal contamination of agricultural soils represents a critical environmental and agronomic challenge, particularly in regions exposed to intensive land use and transport-related emissions. This study presents a detailed assessment of soil contamination in the Dargov cadastral area (Eastern Slovakia), where elevated concentrations of Cu, Zn, Pb, Ni, As, Cd, and Cr were detected through multi-depth sampling near the I/19 first-class road. Analytical results confirmed exceedances of Slovak regulatory thresholds (Decree No. 59/2013), with persistent contamination observed even in the deepest sampling interval (20–40 cm), indicating vertical migration and long-term accumulation. Concentrations of Pb (85–210 mg·kg⁻¹), Cd (2.1–5.4 mg·kg⁻¹), Zn (120–340 mg·kg⁻¹), and Ni (45–95 mg·kg⁻¹) exceeded Slovak regulatory thresholds. The highest values were consistently detected in the 0–10 cm layer and within 3 m of the I/19 road, with a gradual decline at greater depths and distances. Nevertheless, Cd and Ni remained above permissible limits even in the deepest sampling interval (20–40 cm), confirming vertical migration and long-term persistence of contamination. The spatial distribution of contaminants suggests a dominant influence of road traffic, with implications for crop safety, soil fertility, and rural land management. Based on the findings, the study proposes context-sensitive remediation strategies, including phytoremediation and chemical immobilization, and emphasizes the need for integrated monitoring systems and land-use planning to mitigate risks. The case study contributes to the broader discourse on sustainable soil management in Central European agricultural landscapes affected by diffuse pollution. Full article

This study conducted an intensive air quality model evaluation as a response to the urgent need to understand the reliability, consistency, and uncertainty of air quality models supporting the implementation of the PM_2.5 Air Pollution Control Action Plan in China. Five regional air quality models of CMAQ version 5.02, CMAQ version 5.3.2, CAMx version 6.2, CAMx version 7.1, and NAQPMS have been evaluated for the CO, SO₂, NO₂, O₃, PM₁₀, and PM_2.5 concentration and components. A unified statistical method and the same observational data set of 2017, comprising 17 air pollution episodes collected from four super monitoring stations in the regions of Beijing–Tianjin–Hebei, Yangtze River Delta, Pearl River Delta, and Chengdu–Chongqing in China, have been used for the evaluation. All the participating models performed well in simulating the mean PM_2.5 concentrations, with an NMB ranging from −0.29 to −0.04, showing that the participating models are basically suitable for simulation and as evaluation tools for PM_2.5 in regulatory applications. However, the participating models showed a great variability for PM_2.5 components, with the NME ranging from 0.48 to 0.53. The models performed reasonably well in simulating the mean sulfate, nitrate, BC, and NH₄⁺ concentration in PM_2.5, while they were diversified in simulating the mean OC concentrations. The participating models also consistently performed well in simulating the concentration of NO₂, CO, and O₃. However, the models generally overestimated SO₂ concentrations, and to some extent underestimated PM₁₀ concentrations, which is likely attributable to uncertainties in emission sources and the rapid implementation of strict control policies for SO₂. The evaluation work of this study shows that there remains significant potential for further enhancement. Updating and improving the emission inventory should be prioritized to achieve better results, and further investigations into the uncertainties associated with the meteorological simulations, chemical mechanisms, and physical parameterization options of air quality models should also be conducted in future work. Full article

This study provides a detailed assessment of groundwater salinization in the Quaternary aquifer of the Samba Dia region, Senegal, using an integrated approach that combines hydrochemical, stable isotopic (δ²H, δ¹⁸O), and electrical resistivity tomography (ERT) techniques. Fourteen high-resolution ERT profiles, along with comprehensive chemical and isotopic analyses, were performed to identify the main causes of salinity and their spatial distribution. Results show that groundwater salinization in the area is primarily driven by three mechanisms: seawater intrusion, surface salt leaching, and ion exchange. Hydrochemical facies evolution diagrams, ionic ratios, and isotopic signatures helped differentiate marine-influenced zones from inland salinization areas. ERT imaging also mapped the three-dimensional extent and geometry of saline interfaces, confirming zone-specific mixing of seawater and freshwater. The findings indicate that salinization of the coastal aquifer has worsened over the past twenty years, mainly due to human activities and climate variability. This study recommends a sustainable monitoring strategy to support aquifer management, focusing on accurately identifying vulnerable zones and enabling adaptive resource planning in semi-arid Senegal. Full article

Vast areas of natural rangelands in the Kingdom of Saudi Arabia (KSA) suffer from deterioration due to the scarcity of vegetation cover and poor soil quality. Assessing soil quality in rangelands is crucial to identifying degraded lands and to implementing proper sustainable management practices. In this study, a total data set (TDS) containing 27 physical and chemical soil indicators was generated for three rangelands (Al-Fahyhyl, Al-Sahwa, and Al-Tamryate) in KSA. Principal component analysis (PCA) and analytic hierarchy process (AHP) analysis were employed to establish a minimum data set (MDS) and to evaluate key physical and chemical properties affecting soil quality, along with the associated weight factor for each indicator. Results indicated that the MDS represented ≥70% of the total variability of the TDS and accurately estimated the soil quality index (SQI) based on determined physical and chemical soil properties in the study regions. Linear regression indicated high correlation between SQI-TDS and SQI-MDS, with the R² ranging between 0.51–0.87. On the surface layer (0–30 cm), the MDS contained seven soil indicators (sand, dispersion ratio (DR), mean weight diameter (MWD), bulk density (BD), total organic carbon (TOC), available phosphorus (Pa), and available potassium (Ka)), whereas in the sub-surface layer it contained six indicators (sand, DR, MWD, BD, TOC, Pa, and Ka). In all regions, sand had the largest weight factor (0.4514–0.4835), followed by TOC (0.2441–0.2512). Under the arid climate present in all the study sites, sand and TOC levels are crucial for nutrient retention, soil structure, and water retention. Most of the study areas had very low and low SQI (Al-Fahyhyl, 74.4%; Al-Sahwa, 61.8%; and Al-Tamryate, 81.7%), indicating an immediate need for suitable agricultural practices such as reduced tillage, increased organic amendments, and proper water management. The outcomes of this study offer valuable insights for land managers, legislators, and agricultural stakeholders to pinpoint regions in need of development, conduct comprehensive and continuous monitoring of SQI in rangeland areas, and implement land management plans for rangeland rehabilitation and environmental sustainability. Full article

In the rapid development process of cities, as important ecological corridors and landscape carriers, the water quality conditions of urban water bodies are not only related to the health of the ecological environment, but also closely linked to the quality of life of residents. The landscape pattern, as an important component of the urban ecosystem, has a potential impact on water quality. As a tropical coastal city, the unique water network pattern of Haikou City is facing the dual challenges of landscape fragmentation and water quality pollution in its rapid urban expansion. In order to study the impact of the landscape pattern of Haikou City on urban water bodies, this study takes the urban water bodies of Haikou City as the research object. By comprehensively applying landscape ecology methods and water quality monitoring techniques, and using landscape pattern indices (such as the number of patches, fragmentation degree, spread degree, etc.) and on-site investigation of water quality parameter data (such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), etc.), and by using correlation analysis and redundancy analysis, we explore the mechanism by which landscape patterns affect water quality. The results show that: (1) There are significant differences in water quality among water bodies. The concentrations of COD and TN in Hongcheng Lake are relatively high. The average values reached 86.603 mg/L and 13.368 mg/L, respectively, mainly affected by the high-intensity construction land around. Jinniu Lake has a high degree of landscape fragmentation and relatively high concentrations of NH3-N and TP. The average values are 2.086 mg/L and 0.154 mg/L, respectively. The Meishe River has a strong water purification capacity due to its good vegetation coverage. (2) The influence of landscape pattern on water quality has a scale effect. Hongcheng Lake, Jinniu Lake, and Meishe River all have the best interpretation rate of water quality in the 2000 m buffer zone landscape pattern. (3) The expansion of construction land has significantly exacerbated water pollution, while natural vegetation landscapes with high connectivity and low fragmentation can effectively improve water quality. The research reveals the correlation between urban landscape planning and water quality protection. It is suggested that by enhancing ecological connectivity, controlling non-point source pollution, and implementing differentiated seasonal management, the self-purification capacity of water bodies can be improved, providing a scientific basis for ecological restoration and sustainable development in Haikou City. Full article

Increasing attention has been given to the environmental impact of tire-derived chemicals in aquatic systems, but submerged whole tires remain an overlooked source. This study investigates a previously unexplored underwater tire dump in Hjelmås Bay, Alver Municipality (Norway) where a blast mat manufacturer discarded large quantities of tires into the bay in the 1970s. These tires have remained submerged for over 50 years. We conducted an initial site mapping and collected sediment and water samples to assess tire-related pollutants in comparison with control sites. Sediment analysis revealed elevated levels of Zn, Pb, and Cu, particularly near the tire dump center, with Zn being the most abundant. Bis(2-ethylhexyl) phthalate (DEHP) was the dominant phthalate detected in the sediments, though no clear spatial pattern emerged for phthalates. Non-target chemical screening of water samples identified 20 features potentially linked to tire degradation, with N,N′-Diphenylguanidine (DPG) being the most notable. Our study highlights the long-term environmental persistence of several tire-derived chemicals, which has ramifications for both the regulation of tire-derived chemicals and plans for remediation at Hjelmås. Our initial findings warrant the implementation of a comprehensive chemical and ecological baseline monitoring assessment prior to discussions on remediation. Full article