World Health Organization Standards Research Articles

Assessment of Indoor Particulate Matter and Teacher's Perceived Indoor Climate in Government Schools of Bilaspur District, Chhattisgarh, India: A Cross-Sectional Study.

Indoor air pollution (IAP) affects the long-term health, cognitive growth, and academic performance of children. Since children spend most of their time at school, quantifying IAP in classrooms is an important parameter for air pollution. To assess the average particulate matter (PM) levels inside and outside of classrooms along with their associated factors and teacher's perceived indoor climate. Cross-sectional survey in nine government-run schools. PM2.5 and PM10 were measured inside the classroom and outdoors simultaneously during summers, using an Atmos monitor for two consecutive days, along with several school and classroom characteristics. Perception about indoor air quality was captured from teachers (n = 15) using a validated questionnaire. Mean values of PM using mixed effect linear regression. Perceived indoor air quality is presented using percentages. Mean indoor PM2.5 and PM10 was 52.5 µg/m3 and 65 µg/m3. Indoor and outdoor PM levels were highly correlated, but the indoor-outdoor ratio of PM concentrations was more than 1. Teachers were mostly bothered by dust, dirt, and noise in the schools. Indoor air quality was higher than World Health Organization (WHO) standards but within the national standards. Need further research to find the exact cause for higher indoor PM levels compared to outdoor PM levels.

Assessment of tube well water quality in selected residential areas in Khulna

Clean water is vital for sustainable development, fostering socio-economic growth, ecological stability, and human survival. The study aimed to evaluate the quality of tube well water in specific residential areas of Khulna for drinking purposes, comparing it with the standards of World Health Organization (WHO) and Bangladesh (BD). Twenty tube well water samples were collected from residential areas at depths of 700-1500 ft. The samples were tasted with about 20 parameters, including physical: color, taste, odor, total dissolved solids (TDS) and total suspended solids (TSS); chemical: acidity/alkalinity (pH), arsenic (As), electrical conductivity (EC), dissolved oxygen (DO), bicarbonate (HCO3–), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), chloride (Cl–), iron (Fe), phosphate (PO43–), sulfate (SO42–), potassium (K+); and bacteriological parameters: total coliforms and E. coli bacteria. Most of the samples were found to have higher TDS (avg. 1380 mg/L), TSS (avg. 620 mg/L), Fe (avg. 20.2 mg/L), K+ (avg. 194.1 mg/L), and Na+ (avg. 439 mg/L) concentrations compared to the WHO and BD Standards. 90 to 95% of samples exhibited acceptable levels of EC, pH, DO, Mg2+, Ca2+, Cl–, and SO43–. The salinity levels in most of the samples were excessive to be used for drinking, and the levels were especially very high in samples S-01(Na+ 820 and Cl- 3195 mg/L) and S-04 (Na+ 660 and Cl- 2946 mg/L). The arsenic levels were found to be higher than acceptable limit in S-01 (0.086 mg/L) and S-04 (0.091 mg/L) as well. E. coli and other bacteria in a few samples (S-01, 04, 13, 16, 17, 19) were detected.

GROUNDWATER QUALITY ASSESSMENT IN THE RIVER ATBARA ALLUVIAL SEDIMENTS, EASTERN SUDAN

GROUNDWATER QUALITY ASSESSMENT IN THE RIVER ATBARA ALLUVIAL SEDIMENTS, EASTERN SUDAN

Solid CaCO3 Formation in Glioblastoma Multiforme and its Treatment with Ultra-Nanoparticulated NPt-Bionanocatalysts.

Glioblastoma multiforme (GBM), the most prevalent form of central nervous system (CNS) cancer, stands as a highly aggressive glioma deemed virtually incurable according to the World Health Organization (WHO) standards, with survival rates typically falling between 6 to 18 months. Despite concerted efforts, advancements in survival rates have been elusive. Recent cutting-edge research has unveiled bionanocatalysts with 1% Pt, demonstrating unparalleled selectivity in cleaving C-C, C-N, and C-O bonds within DNA in malignant cells. The application of these nanoparticles has yielded promising outcomes. The objective of this study is to employ bionanocatalysts for the treatment of Glioblastoma Multiforme (GBM) in a patient, followed by the evaluation of obtained tissues through electronic microscopy. Bionanocatalysts were synthesized using established protocols. These catalysts were then surgically implanted into the GBM tissue through stereotaxic procedures. Subsequently, tissue samples were extracted from the patient and meticulously examined using Scanning Electron Microscopy (SEM). Detailed examination of biopsies via SEM unveiled a complex network of small capillaries branching from a central vessel, accompanied by a significant presence of solid carbonate formations. Remarkably, the patient subjected to this innovative approach exhibited a three-year extension in survival, highlighting the potential efficacy of bionanocatalysts in combating GBM and its metastases. Bionanocatalysts demonstrate promise as a viable treatment option for severe cases of GBM. Additionally, the identification of solid calcium carbonate formations may serve as a diagnostic marker not only for GBM but also for other CNS pathologies.

Assessing the quality of drinking water from selected water sources in Mbarara city, South-western Uganda.

This study assessed the physical, chemical, and microbiological quality with emphasis on risk score, source apportionment, geochemistry, feacal coliforms and water quality index of drinking water from selected water sources. A cross-sectional study was conducted in six villages in Mbarara city, south-western Uganda. Each selected source was inspected using a WHO-adopted sanitary inspection questionnaire. Each source's risk score was calculated. Thirty-seven samples were taken from one borehole, nine open dug wells, four rain harvest tanks, and twenty-three taps. The values for apparent color and phosphate were higher than the permissible level as set by the World Health Organization and Ugandan standards (US EAS 12). The isolated organisms were Klebsiella spp. (8.11%), Citrobacter divergens (62.16%), Citrobacter fluendii (2.7%), E. coli (35.14%), Enterobacter aerogenes (8.11%), Enterobacter agglomerus (5.4%), Proteus spp. (2.7%), Enterobacter cloacae (13.5%), and Proteus mirabilis (2.7%). Twelve water sources (32.4%) had water that was unfit for human consumption that was unfit for human consumption (Grade E), Five sources (13.5%) had water that had a very poor index (Grade D), nine (24.3%) had water of poor index (Grade C), eight (21.6%) had water of good water index (Grade B), and only three (8.1%) had water of excellent water quality index (Grade A). The piper trilinear revealed that the dominant water type of the area were Mgso4 and Caso4 type. Gibbs plot represents precipitation dominance. PCA for source apportionment showed that well, tap and borehole water account for the highest variations in the quality of drinking water. These results suggest that drinking water from sources in Mbarara city is not suitable for direct human consumption without treatment. We recommend necessary improvements in water treatment, distribution, and maintenance of all the available water sources in Mbarara City, South Western Uganda.

An evaluation of LLIN physical integrity and population attitudes towards net use, care and handling during the Magude project in southern Mozambique

BackgroundThe Magude Project assessed the feasibility of eliminating malaria in Magude district, a low transmission setting in southern Mozambique, using a package of interventions, including long-lasting insecticidal nets (LLINs). As the efficacy of LLINs depends in part on their physical integrity, this metric was quantified for Olyset® Nets post mass-distribution, in addition to net use, care and handling practices and other risk factors associated with net physical integrity.MethodsNets were collected during a cross-sectional net evaluation, nine months after the Magude project commenced, which was 2 years after the nets were distributed by the National Malaria Control Programme (NMCP). The physical integrity of the nets was assessed by counting and sizing the holes at different positions on each net. A structured questionnaire was administered to assess how the selected net was used and treated (care, wash and repair). Net bio-efficacy was assessed following the standard World Health Organization (WHO) cone bioassay procedures.ResultsOut of the 170 Olyset® Nets included in the analysis, 63.5% had been used the night before. The main reason for not using a net was the notion that there were no mosquitoes present. The average number of people using each net was 1.79. Two thirds of the nets had only been washed once or twice since distribution. Most nets (80.9%) were holed and 18% were torn, but none of the risk factors were significantly associated with net integrity, except for presence of mice in the household. Less than half of the participants noticed holes in holed nets, and of those only 38.6% attempted to repair those. None of the six nets that were tested for bio-efficacy passed the WHO threshold of 80% mosquito mortality.ConclusionOverall the majority of Olyset® Nets were in serviceable condition two years post-distribution, but their insecticidal effect may have been lost. This study—together with previous evidence on suboptimal access to and use of LLINs in Magude district—highlights that LLINs as an intervention could have been optimized during the Magude project to achieve maximum intervention impact.

Separation and reutilization of heavy metal ions in wastewater assisted by p-BN adsorbent

Extracting heavy metal ions from wastewater has significant implications for both environmental remediation and resource preservation. However, the conventional adsorbents still suffer from incomplete ion removal and low utilization efficiency of the recovered metals. Herein, we present an extraction and reutilization method assisted by porous boron nitride (p-BN) containing high-density N atoms for metal recovery with simultaneous catalyst formation. The p-BN exhibits stable and efficient metal adsorption performance, particularly for ultra-trace-level water purification. The distribution coefficients towards Pb2+, Cd2+, Co2+ and Fe3+ can exceed 106 mL g−1 and the residual concentrations that reduced from 1 mg L−1 to 0.8–1.3 μg L−1 are much lower than the acceptable limits in drinking water standards of World Health Organization. Meanwhile, the used p-BN after Co ion adsorption can be directly adopted as a high-efficiency catalyst for activating peroxymonosulfate (PMS) in organic pollutant degradation without additional post-treatment, avoiding the secondary metal pollution and the problems of neglected manpower and energy consumption. Moreover, a flow-through multistage utilization system assisted by p-BN/polyvinylidene fluoride (PVDF) membrane is constructed for achieving both metal ion separation and reutilization in the removal of organic pollutants, providing a new avenue for sustainable wastewater remediation.

Assessment of seasonal variations in vehicular emissions at traffic intersections in Ibadan using AERMOD dispersion model

AbstractAfrican cities grapple with urban air pollution from traffic‐related air pollutants (TRAPs). This study investigated TRAPs concentration variations at traffic intersections (TIs) in Ibadan, Nigeria. AERMOD model was employed to examine TRAPs dispersion at 25 selected TIs, considered as volume sources. Seasonal concentration distributions of six pollutants (CO, NO2, SO2, TVOCs, PM2.5, and PM10) were determined using meteorological, topographical, and pollutants’ emission rates in AERMOD. Estimated peak concentrations of the studied pollutants were generally higher in the rainy season than dry season, surpassing the air quality standards set by World Health Organization (WHO) and Nigeria's National Environmental Standards and Regulations Enforcement Agency (NESREA) during the rainy and dry seasons except SO2 (24 h) concentration which did not exceed the NESREA standard. This study highlighted TIs as significant contributors to air quality degradation in both seasons studied in Ibadan and showed AERMOD's suitability for air dispersion studies.

Heavy Metal-Related Health Risk Assessment of Cultivated Plants Around a Cement Factory in Sokoto North Western, Nigeria

The pollution of the environment by cement manufacturing companies is becoming a global concern, particularly in developing nations. This study assessed the levels of heavy metals and their associated health risks in sugarcanes (Saccharum officinarum), tomatoes (Solanum lycopersicum), and almonds (Prunus dulcis) cultivated in the vicinity of a cement factory in Sokoto, Nigeria. Samples of these plants were collected, treated, and then assayed for lead (Pb), copper (Cu), cadmium (Cd), and zinc (Zn) using atomic absorption spectroscopy (AAS). The values obtained were compared against the permissible limits established by the World Health Organization (WHO), and these results were used to estimate the potential health risks associated with consuming these plants. The findings revealed that both the Solanum lycopersicum and Saccharum officinarum contained non-tolerable levels of Cu, Cd, Pb, and Zn, while Prunus dulcis had non-tolerable levels of Zn only. Additionally, the concentrations of individual heavy metals in each of the three plant species showed a significant difference (p ≤ 0.05) from the respective WHO standards. The estimated daily intake (EDI) and target hazard quotient (THQ) for all the heavy metals were within the recommended limits, except for the EDI of Pb in Saccharum officinarum and the THQ of Pb in Solanum lycopersicum. The health risk index (HRI) for all the heavy metals in the three plants exceeded the tolerable limit (> 1). These findings indicate that daily consumption of these plants may pose health hazards. Therefore, the practice of cultivating plants in the vicinity of cement factories should be discouraged.

Leading Causes of In-Hospital Death of Older Patients of Different Age Groups in Shanghai.

Despite great achievements in clinical medicine, the in-hospital mortality of older patients remains high. How to reduce the in-hospital mortality of older inpatients is of great clinical value in clinical practice. This study is to analyze the leading causes of in-hospital death of older inpatients of different ages in Shanghai. An observational study was conducted in Shanghai. A total of 3894 older inpatients (≥60 years old) were investigated. According to the age stratification standard of World Health Organization, they were divided into young older patients group (aged 60 to 74), old older patients group (aged 75 to 89) and very old patients group (aged ≥90). Diseases of in-hospital death of older inpatients in different age groups were classified according to the 10th edition of the International Classification of Diseases. Constituent ratio of causes of in-hospital death in each group was analyzed. The constituent ratio of pulmonary infection had the highest rate of in-hospital death in older patients. The constituent ratio of lung malignant tumors had the highest rate of in-hospital death in young older patients. The constituent ratio of pulmonary infection had the highest rate of in-hospital death in old older patients. The constituent ratio of pulmonary infection had the highest rate of in-hospital death in very old patients. The leading cause of in-hospital death of young older patients group was lung malignant tumor. The leading cause of in-hospital death of old older patients group and very older patients group was pulmonary infection. Great importance should be attached to the prevention of lung tumor and lung infection in the elderly. Results of this study will provide a basis for health administrative departments to formulate corresponding health-care policies for older patients.

Pollution indices and correlation of heavy metals contamination in the groundwater around brick kilns in Jammu and Kashmir, India

The present investigation focuses on assessing the water quality of groundwater surrounding brick kilns in the Jammu district of Jammu and Kashmir (J&K). At 43 different brick kiln sites in both north and south regions of Jammu, concentrations of heavy metals were measured using established techniques. The elements zinc, copper, iron, lead, cadmium, nickel, and manganese were analyzed utilizing an Atomic Absorption Spectrophotometer (AAS). The pollution load index value was consistently below unity across all sites, suggesting an absence of pollution and making the water suitable for consumption. The average concentrations, listed in ascending order, were found to be 0.38 mg/L for copper, 0.31 mg/L for zinc, 0.01 mg/L for iron, and 0.09 mg/L for manganese. Notably, concentrations of lead, cadmium, and nickel were found below the detectable levels. Evaluation of contamination factors revealed the sequence Cu > Fe > Zn > Mn, while the geo accumulation index followed the sequence Cu > Fe > Mn > Zn. Comparison of these findings with the established standards of World Health Organization and Bureau of Indian Standards indicated that the recorded ranges were within permissible limits. The study's outcomes suggest that heavy metal emissions from brick kilns may not significantly impact the quality of groundwater. Elevated copper levels found near brick kilns were likely to result from plumbing materials in the study area. Iron and manganese in groundwater seems to have geo-genic origin and not emission-related. This research represents a foundational step in examining groundwater contamination by heavy metals specifically in the neighborhood of brick kilns in Jammu district. It contributes to the establishment of a comprehensive database and serves as a reference point for future studies. Additionally, the study recommends regular monitoring of groundwater to ensure the maintenance of drinking water quality.

WHO Guidelines on Mental Health at Work

The World Health Organization (WHO) published the "Guidelines on mental health at work" in September 2022. WHO developed the guidelines in accordance with WHO standards. The summary of this guideline was translated into German by the team of the WHO Collaborating Center for Evidence-based Medicine at the University for Continuing Education Krems (Austria) for use in German-speaking countries. An estimated 15+% of working-age adults have had some mental disorder at some point of time in their lives. This can lead to impaired capacity to work, resulting in reduction in productivity and performance, and ability to work safely, or in difficulties in retaining their jobs or obtaining gainful employment. The guidelines contain 12 recommendations. These provide evidence-based global public health guidance on organizational interventions, manager and worker training, and individual interventions for the promotion of positive mental health and prevention of mental health conditions, as well as recommendations on returning to work following absence associated with mental health conditions and gaining employment for people living with mental health conditions. Through the provision of these WHO recommendations, it is anticipated that the guidelines will facilitate national and workplace-level actions in the areas of policy development, service planning and delivery in the domains of mental and occupational health.

Lysine-functionalized graphene oxide on cost-effective microporous support: A hydrophilic and fouling resistant membrane for safe lead filtration

The presence of heavy metals in freshwater is a severe problem humanity faces. Remedies with high removal efficiency of heavy metals from contaminated water are crucial. However, existing studies often neglect effluent quality per World Health Organization (WHO) standards. Also, the reported conditions are either unrealistic to the actual contamination levels or unsuitable for large-scale applications. Here, we report the fabrication of zwitterionic graphene oxide (GO) by incorporating a pH-responsive group (i.e., Lysine) using N, N′-diisopropylcarbodiimide (DIC) as a coupling agent. The modified GO-Lys was then coated on a commercially available 0.45-μm Nylon membrane and was tested for selective removal of toxic heavy metals from synthetic water and human blood plasma samples while allowing essential metal ions. Consequently, lead was the most retained toxic metal (i.e., 99.99% retention with effluent quality meeting WHO standards) among nickel, arsenic, cadmium, and mercury (i.e., between 50 to 80% retention). These composite membranes also displayed excellent fouling resistance and inhibited bacterial adhesion onto the membrane surface, while maintaining stable performance over a long time and critical transmembrane pressure conditions. This research marks a significant advancement in environmental technologies, providing an effective solution for selectively removing heavy metal pollutants, with a particular focus on lead detoxification applications.

Heavy Metal Bioaccumulation in Peruvian Food and Medicinal Products.

To better query regional sources of metal(loid) exposure in an under-communicated region, available scientific literature from 50 national universities (undergraduate and graduate theses and dissertations), peer-reviewed journals, and reports published in Spanish and English were synthesized with a focus on metal(loid) bioaccumulation in Peruvian food and medicinal products utilized locally. The study considered 16 metal(loid)s that are known to exert toxic impacts on humans (Hg, Al, Sb, As, Ba, Be, Cd, Cr, Sn, Ni, Ag, Pb, Se, Tl, Ti, and U). A total of 1907 individual analyses contained within 231 scientific publications largely conducted by Peruvian universities were analyzed. These analyses encompassed 239 reported species classified into five main food/medicinal groups-plants, fish, macroinvertebrates and mollusks, mammals, and "others" category. Our benchmark for comparison was the World Health Organization (Codex Alimentarius) standards. The organisms most frequently investigated included plants such as asparagus, corn, cacao, and rice; fish varieties like trout, tuna, and catfish; macroinvertebrates and mollusks including crab and shrimp; mammals such as alpaca, cow, chicken eggs, and milk; and other categories represented by propolis, honey, lichen, and edible frog. Bioaccumulation-related research increased from 2 to more than 25 publications per year between 2006 and 2022. The results indicate that Peruvian food and natural medicinal products can have dangerous levels of metal(loid)s, which can cause health problems for consumers. Many common and uncommon food/medicinal products and harmful metals identified in this analysis are not regulated on the WHO's advisory lists, suggesting the urgent need for stronger regulations to ensure public safety. In general, Cd and Pb are the metals that violated WHO standards the most, although commonly non-WHO regulated metals such as Hg, Al, As, Cr, and Ni are also a concern. Metal concentrations found in Peru are on many occasions much higher than what has been reported elsewhere. We conclude that determining the safety of food/medicinal products is challenging due to varying metal concentrations that are influenced not only by metal type but also geographical location. Given the scarcity of research findings in many regions of Peru, urgent attention is required to address this critical knowledge gap and implement effective regulatory measures to protect public health.

ENVIRONMENTAL ASSESSMENT OF POLLUTION IN AN INDUSTRIAL ENVIRONMENT USING HEAVY METAL POLLUTION INDICES AND STABLE ISOTOPES, CASE STUDY OF THE INDUSTRIAL ZONE OF SKIKDA, NORTH-EAST ALGERIA

An environmental assessment study was conducted in the industrial area of Skikda in the Northeast of Algeria which involved physicochemical parameters, heavy metal concentrations, and stable isotopes of surface water, groundwater, and soil. The results revealed high concentrations of Cd, Ni, Fe, Cu, As, Cr, Pb, Co, and Mn in groundwater. The southern part exhibited the lowest heavy metal concentrations, while the industrial zone in the North contained the highest levels. Therefore, the industrial area showed significant pollution in groundwater by Cr, Pb, and As with respectively 0.5, 0.69, and 0.44 mg/l, surpassing the respective WHO(World Health Organization) standards of 0.05, 0.01, and 0.01 mg/l. Spatial analysis showed that the industrial area presents higher concentrations of As, Cr, Cd, Pb, Cu, Zn, Ni, and Fe which demonstrated similar trends in spatial distribution, their concentrations increasing within the industrial zone. However, the western part had no significant pollution sources except for a public landfill and SONATRACH industrial complex, high concentrations of Co and Mn in the south and the west parts were observed. Mean concentration in soils indicated that Cd is ranged between35.32 to 95.12 ppm, for Fe between 145.1 and 702 ppm, As varies between 1.03 and 81.85 ppm, and Zn between 50 and 520.32 ppm and considered as dominant metals. However, Mn, Co and Cr were lower respectively with 1.97, 12.11 and 7.25 ppm. Cd and As were most influenced by the polluting companies, while Cr was mainly influenced by natural factors, such as pH and soil type. Based on the contamination degree index, the soil pollution levels of Cd, Pb, and As were classified as extremely contaminated. The statistical analysis indicated substantial anthropogenic contributions to groundwater contamination concentrated in the industrial area. The groundwater exhibits a range of δ18O and δ2H values, varying from 2.45 to -5.33‰ and 19.82 to -1.67‰ vs. the V-SMOW (Vienna-Standard Mean Ocean Water) standard, respectively. The mean isotopic composition is -2.50‰ for δ18O, -19.32‰ for δ2H, with a mean deuterium excess of 6.45. These values align with the Meteoric Water Line observed in the western Mediterranean region. It indicates a hydrological connection between recharge and groundwater which suggests a significant interaction between groundwater and surface water. Due to their proximity to the river and the shallow aquifer, the downstream area is more vulnerable to surface pollution. Furthermore, the young groundwater in the downstream can be attributed to the rapid recharge and replenishment of the aquifer caused by rainfall and quick infiltration and sustained by the shallow aquifer depth and sandy soil. Consequently, the rainwater and industrial wastes lead to faster pollutant infiltration. Anthropogenic sources, including industrial effluents from smelting, refining, manufacturing, steel and textile industries, electroplating, nickel-cadmium battery production, welding, PVC product and paint pigment manufacturing, were identified as major contributors to heavy metal pollution.

Assessment of drinking-water quality in the Dibamba watershed (Douala-Cameroon

Background: Residents of Douala including Dibamba watershed collect water from various points to fulfill their freshwater needs. However, it is known that many microorganisms, including parasites, bacteria, viruses, and even alga, are present in water where they form a complex ecosystem. These microorganisms are held responsible for most of the contamination in drinking water and related diseases that threaten health of many individuals. Objectives: This study aims to determine the bacteriological and physicochemical quality of drinking water used by city dwellers in the Dibamba watershed. Methods: A cross-sectional study was conducted in different communities living in the watershed. A total of 58 drinking water samples were randomly collected from a variety of water resources. The analyses were performed for temperature, Ph, and conductivity; and for bacterial parameters, namely, to trace the presence of organisms and opportunistic pathogens indicative of fecal contamination. Results: Water used for consumption purposes have an acidic pH, low dissolved oxygen content, and shows high levels of microorganisms, testifying water pollution due to domestic wastewater discharged without any prior treatment, and coming from domestic, livestock and agricultural activities carried out in the watershed. These contaminated waters contain pathogenic species (Shigella, Salmonella, E.Coli, etc.) suspected of being the cause of waterborne infectious diseases in the watershed.. Conclusion: The results of our study show that 95% of tested drinking water samples are of low microbiological quality. They neither fulfill requirements of World Health Organization standards, nor fit for human consumption. Therefore, Decision-makers and Stake holders should implement practical actions to facilitate access to safe and sufficient drinking water in the watershed.

Identification of groundwater nitrate sources in an urban aquifer (Alborz Province, Iran) using a multi-parameter approach.

High concentrations of NO3̄ in water resources are detrimental to both human health and aquatic ecosystems. Identification of NO3̄ sources and biogeochemical processes is a crucial step in managing and controlling NO3̄ pollution. In this study, land use, hydrochemical data, dual stable isotopic ratios and Bayesian Stable Isotope Mixing Models (BSIMM) were integrated to identify NO3̄ sources and estimate their proportional contributions to the contamination of the Karaj Urban Aquifer (Iran). Elevated NO3̄ concentrations indicated a severe NO3̄ pollution, with 39 and 52% of groundwater (GW) samples displaying the concentrations of NO3̄ in exceedance of the World Health Organization (WHO) standard of 50 mg NO3̄ L-1 in the rainy and dry seasons, respectively. Dual stable isotopes inferred that urban sewage is the main NO3̄ source in the Karaj Plain. The diagram of NO3̄/Cl‾ versus Cl‾ confirmed that municipal sewage is the major source of NO3̄. Results also showed that biogeochemical nitrogen dynamics are mainly influenced by nitrification, while denitrification is minimal. The BSIMM model suggested that NO3̄ originated predominantly from urban sewage (78.2%), followed by soil organic nitrogen (12.2%), and chemical fertilizer (9.5%) in the dry season. In the wet season, the relative contributions of urban sewage, soil nitrogen and chemical fertilizer were 87.5, 6.7, and 5.5%, respectively. The sensitivity analysis for the BSIMM modeling indicates that the isotopic signatures of sewage had the major impact on the overall GW NO3̄ source apportionment. The findings provide important insights for local authorities to support effective and sustainable GW resources management in the Karaj Urban Aquifer. It also demonstrates that employing Bayesian models combined with multi-parameters can improve the accuracy of NO3̄ source identification.

Photovoltaic-integrated advancements for sustainable water production: Developing and evaluating an enhanced hybrid solar desalination system

The global water crisis demands innovative solutions, and solar desalination is a promising avenue. However, traditional systems often suffer from low yields. This study centres on the development, assessment, and economic feasibility of the Enhanced Hybrid Solar Still (EHSS), a pioneering approach to sustainable clean water production. Integrating photovoltaic technology, the EHSS targets a minimum daily output of 15 L/m2. Computational Fluid Dynamics (CFD) simulations guide the design optimisation, identifying an optimal configuration of 4 mm basin thickness, a 2 mm glass cover thickness, and a 56° slope. The EHSS is a single component that comprises of passive operation and advanced components integration, including monocrystalline solar panels, a hybrid MPPT inverter, a deep cycle battery, and a custom water heater, to enhance the yield. The EHSS undergoes a comprehensive assessment encompassing distillate quality, efficiency, and economic viability. In passive mode operation (solely using solar radiation), clean water yields range from 4.7111 L/m2·day to 2.1309 L/m2·day. Transitioning to active mode operation (employing photovoltaics and additional components) significantly enhances yields to a range of 19.7 L/m2·day. Impressively, the EHSS consistently delivers an average daily water yield of 16.85 L/m2, and also its purity meets World Health Organization standards for drinking water. The PV systems exhibit a charge rate of 14.28 % per hour on clear days and 9 to 11 % per hour on semi-cloudy days, with the battery depleting at 16.66 % per hour at 70 °C operational temperature. Comparative analysis against traditional systems showcases an efficiency increase from 25.61 % to an outstanding 64.01 % for the optimised EHSS (PV system and appurtenances). A strong correlation (coefficient of 0.9701) between experimental and simulation results indicates robust relationships. Over a 20-year lifespan, cost analysis reveals a per-litre cost of 0.0892 US dollars for the EHSS, compared to 0.0374 US dollars for traditional systems. Extended lifespans further underscore the economic feasibility of the EHSS, emphasizing its role in providing sustainable clean water solutions.

Land-use and its implication on physicochemical parameters of groundwater: Evidence from Ikenne Local Government Area, Ogun State

Groundwater is essentially the major source of fresh water and used widely for drinking purpose. In any given area, groundwater within an aquifer, or groundwater produced by a well, has some vulnerability to contamination from human activities. Therefore, information on human activities that leads to contamination of groundwater is important. Such information can aid in the choice of proper locations for certain activities, so that the adverse effects on groundwater are minimized and protection of groundwater achieved. Against this background, the study examines land-use and its implications on physiochemical properties of groundwater in Ikenne Local Government Area, Ogun State, Nigeria. The study obtains and analyses the existing land-use maps. Water samples were collected for laboratory test to benchmark physicochemical parameters based on World Health Organisation standards. Water Quality Index (WQI) was used to determine groundwater quality. Findings from analyses of land-use map show that residential landuse has highest percentage in Iperu (79.9%) and Ilishan (52.8%) towns, while industrial land-use constitutes the least, representing for 0.6% and 1.9% in Iperu and Ilishan respectively. The study found that WQI for Ilishan I (39.4), II (33.5), III (43.8) and Iperu I (32.9), II (31.4) was of good quality, while Iperu III (19.4) was excellent. ANOVA results of F = 0.596 and p > 0.05 established that there is no statistical significant variation in the physiochemical properties of groundwater. It can be concluded that absence of land-uses that generate contaminants reduce the likelihood of groundwater contamination. Therefore, strategies for effective implementation of zoning regulations should be put in place by relevant government agency.

Assessment of functioning in ADHD according to World Health Organization standards: First revision of the International Classification of Functioning, Disability and Health Core Sets.

To conduct the first revision of the World Health Organization International Classification of Functioning, Disability and Health (ICF) Core Sets for attention-deficit/hyperactivity disorder (ADHD). A Delphi-like method was used, integrating evidence from stakeholder feedback and developing and piloting the ADHD ICF Core Set platform to inform revisions to the ADHD Core Sets. A total of 27 second-level ICF codes were added to the comprehensive ADHD Core Set: body functions of temperament and personality, and basic sensory functions; activities and participation in terms of learning to read and write, spoken communication, community life, religion and spirituality, education, economy, and human rights; environmental factors for domestic animals; and several societal services. The revised comprehensive Core Set contains 98 ICF codes: 18 body function codes; 47 activities and participation codes; and 33 environmental factor codes. Extensive changes were also made to the age-appropriate brief Core Sets to allow their independent use in research and clinical practice. Although substantially expanded, the revised ICF Core Sets better reflect the lived experience of individuals with ADHD and clinical implementation preferences than the initial sets. We recommend further feasibility and validation studies of these Core Sets with the goal of optimizing their acceptance and practicability, and strengthening their evidence base.