WHO Guideline Value Research Articles

HYDROCHEMICAL STUDY OF BALAK RIVER, ERBIL-IRAQ

This study was aimed to assess the water quality of different water resources (Surface water, subsurface in water, and groundwater) across the Balak river basin. Twenty two different water resource samples were collected and subjecting to a comprehensive physicochemical analysis. Balak river basin, situated in Erbil governorate, Iraq, it is located 10 km to the east from Bekhal Waterfall. Five attributers combine with Balak River within the basin areas which are: Rezanok Sub River, Balakiyan Sub River, Basan Sub River, Roste Sub River, and Alana Sub River. The hydro chemical study of all water resources during the investigated period revealed that the spring waters are relatively higher in electrical conductivity value compared to other sources. Some surface water samples were recorded high turbidity value. Values recorded for physicochemical parameters were within WHO and Iraqi standards guideline values except for some samples of turbidity. According to water classification, all samples have a very similar composition, and can be classified as Ca-HCO3 water. This indicated that they correspond to different sampling points along different rivers, and different samples along the same river.

Surface water quality assessment and probable health threats of metal exposure in the Tano South Municipality, Ahafo, Ghana

The prime goal of this study was to assess the surface water quality and the associated health risks for residents in the Tano South Municipality, Ghana. The WHO drinking water criteria were compared with the findings of an analysis of eight surface waters for parameters such as physiochemical parameters, nutrient levels, and concentrations of selected metals. An evaluation was performed regarding the potential non-carcinogenic and carcinogenic risks associated with metal exposure by oral and dermal absorption. The estimated water quality index indicated that seven water samples were deemed unsuitable for human consumption, while one sample indicated very low water quality. The fluoride levels in all water samples were below the limit of detection, although it guards against dental caries. All of the water samples had mean concentrations of Cd and Fe above WHO guideline values, while one water sample had a Pb concentration that was higher than recommended. Principal component analysis showed that aside from the natural source, human-induced sources such as runoff of excess chemicals and soil erosion from adjacent farm soils were responsible for the substantial levels of contaminants in surface water samples. There was a possibility of non-carcinogenic consequences for children in seven out of eight water samples. However, cancer risk for Cd and Pb was not likely for adults and children in the study area. Findings serve as a representative case study for other districts and call on water managers to treat surface waters to guard against harmful health consequences and safeguard the designated buffer zones.

Assessment of Polycyclic Aromatic Hydrocarbons in Urban Water Bodies: A Study of Rivers and Lakes in Dhaka, Bangladesh

Polycyclic aromatic hydrocarbons (PAHs) pose significant environmental and health risks due to their toxic properties,making their assessment in urban water bodies crucial. This study aims to evaluate the presence of three notable PAHs—anthracene, fluoranthene, and benzo[a]pyrene—in the surface water of three rivers (Buriganga, Meghna, and Turag) andtwo lakes (Hatirjheel and Gulshan) in Dhaka, Bangladesh. High-performance liquid chromatography with fluorescencedetector (HPLC-FD) was employed and validated for PAH determination, using solid phase extraction (SPE) withpreconditioned C-18 SPE cartridge for sample extraction. Calibration showed excellent linearity with correlation coefficient (R²) ≥ 0.999. The limits of detection (LODs) were 200 ng/L for anthracene and 0.63 ng/L for both fluoranthene and benzo[a]pyrene, with corresponding limits of quantification (LOQs) of 660 ng/L and 2.08 ng/L, respectively. Percent recovery was 91.38% for anthracene, 85.49% for fluoranthene, and 95.72% for benzo[a]pyrene, with relative standard deviations (RSD) of 5.27, 17.55 and 2.84%, respectively. Most water samples had PAH levels below detection limits (bdl) such as anthracene (bdl-1789.57 ng/L), fluoranthene (bdl-1309.23 ng/L), and benzo[a]pyrene (bdl-25.17 ng/L), and the detected concentrations were significantly lower than WHO and USEPA guideline values. This indicates a relatively low level of PAHs contamination in the studied water bodies. Dhaka Univ. J. Sci. 72(2): 75-83, 2024 (July)

Indoor Environmental Quality and Effectiveness of Portable Air Cleaners in Reducing Levels of Airborne Particles during Schools’ Reopening in the COVID-19 Pandemic

Educational buildings tend to fail in the contagion containment of airborne infectious diseases because of the high number of children, for several hours a day, inside enclosed environments that often have inadequate indoor air quality (IAQ) conditions. This study aimed to assess indoor environmental quality and test the effectiveness of portable air cleaners (PACs) in alleviating airborne particle levels in schools of Central–Southern Spain during the period of reopening after the lockdown due to the COVID-19 outbreak. To accomplish this, three sampling campaigns were organized from September to December 2020 to consistently monitor temperature and relative humidity, carbon dioxide, and particulate matter in nineteen classrooms (seven school buildings). Results showed that although the recommendation of maintaining the windows open throughout the day seemed to be effective in promoting, in general, proper ventilation conditions (based on CO2 levels). For the colder campaigns, this practice caused notorious thermal comfort impairment. In addition, a great number of the surveyed classrooms presented levels of PM2.5 and PM10, attributable to outdoor and indoor sources, which exceeded the current WHO guideline values. Moreover, considering the practice of having the windows opened, the installation of 1 unit of PACs per classroom was insufficient to ensure a reduction in particle concentration to safe levels. Importantly, it was also found that children of different ages at different education levels can be exposed to significantly different environmental conditions in their classrooms; thus, the corrective measures to employ in each individual educational setting should reflect the features and needs of the target space/building.

Assessment on the Exposure of Air, Water and Noise Pollution, and Mental Stress on Preeclamptic Patients of Rajshahi, Bangladesh

Although preeclampsia claims the lives of 70,000 mothers and 500,000 newborns each year worldwide, its origin is still elusive and a number of risk factors such as environmental pollution are not yet addressed properly. In this study, exposures due to the extents of air, water and noise pollution as well as mental stress on preeclamptic patients have been investigated. Using a cross-sectional longitudinal design, 90 women hospitalized with preeclampsia in 7 hospitals of Rajshahi, Bangladesh were considered, of which Rajshahi Medical College Hospital is a tertiary referral hospital. The data were collected by interviewing the patients, physical examinations and merging the patients’ data with British Geological Survey’s groundwater data-sets (n=3,540). For statistical analyses, SPSS software was employed. It was found that most of the patients’ living rooms were within 15 feet from kitchen. Only 10% patients had good room ventilation, while the remaining 90% patients had either moderate or poor room ventilation. Combination of these facts reveals that the preeclamptic patients were subject to moderate CO2 exposure. Since 79% of the preeclamptic patients’ living rooms were below 50 ft from the nearest roads and 84% for 100 ft distance, they would experience noise pollution. Combination of traffic conditions and potential sources of noise pollution revealed that 60% of the preeclamptic patients experienced moderate to intense noise pollution. Groundwater arsenic, calcium, magnesium, iron and sodium concentrations in the patients’ drinking water were higher than WHO guideline values that should favour constipation and mild hypertension. While 70% patients were under high mental stress and 24% under very high mental stress, only 6% patients had moderate mental stress. It is concluded that air, water and noise pollution, and mental stress are potential risk factors of preeclampsia.

Particulate and gaseous air pollutants exceed WHO guideline values and have the potential to damage human health in Faisalabad, Metropolitan, Pakistan

First-ever measurements of particulate matter (PM2.5, PM10, and TSP) along with gaseous pollutants (CO, NO2, and SO2) were performed from June 2019 to April 2020 in Faisalabad, Metropolitan, Pakistan, to assess their seasonal variations; Summer 2019, Autumn 2019, Winter 2019–2020, and Spring 2020. Pollutant measurements were carried out at 30 locations with a 3-km grid distance from the Sitara Chemical Industry in District Faisalabad to Bhianwala, Sargodha Road, Tehsil Lalian, District Chiniot. ArcGIS 10.8 was used to interpolate pollutant concentrations using the inverse distance weightage method. PM2.5, PM10, and TSP concentrations were highest in summer, and lowest in autumn or winter. CO, NO2, and SO2 concentrations were highest in summer or spring and lowest in winter. Seasonal average NO2 and SO2 concentrations exceeded WHO annual air quality guide values. For all 4 seasons, some sites had better air quality than others. Even in these cleaner sites air quality index (AQI) was unhealthy for sensitive groups and the less good sites showed Very critical AQI (> 500). Dust-bound carbon and sulfur contents were higher in spring (64 mg g−1) and summer (1.17 mg g−1) and lower in autumn (55 mg g−1) and winter (1.08 mg g−1). Venous blood analysis of 20 individuals showed cadmium and lead concentrations higher than WHO permissible limits. Those individuals exposed to direct roadside pollution for longer periods because of their occupation tended to show higher Pb and Cd blood concentrations. It is concluded that air quality along the roadside is extremely poor and potentially damaging to the health of exposed workers.Graphical abstract

Colorimetric detection of Pd2+ and Ni2+ ions using a probe having benzo[d]imidazo[2,1-b]thiazole and pyrene rings: Application in detection of Pd2+ ion in anti-hypertensive drugs

Pd-complexes are widely used in the pharmaceutical industry to synthesize APIs and drug molecules. It is imperative to detect even trace amounts of Pd impurities in them. A probe (E/Z)-N'-(pyren-1-ylmethylene)benzo[d]imidazo[2,1-b]thiazole-2-carbohydrazide (LH) having benzo[d]imidazo[2,1-b]thiazole and pyrene rings has been synthesized. LH was found to exhibit a change from colourless to yellowish green in presence of Pd2+ and Ni2+ ions. This colorimetric “turn on” response has also been observed with Pd2+ ions in the presence of “sartan” drugs, namely telmisartan, valsartan, irbesartan, olmesartan medoxomil and losartan potassium. The limit of detection ranged from 46.1 to 93.9 nM (4.9 to 6.0 ppb) for PdCl2 and 10.6 to 19.6 nM (1.1 to 2.1 ppb) for Pd(PPh3)2Cl2 and these are lower than the limit suggested by the EMA. The LOD values of Ni2+ ion was 9.301 nM which is also lower than the WHO guideline value. This probe showed a remarkable ability to recover Pd2+ ions from the spiked solution of drug samples. The probe formed stable 1:1 complexes with both the metal ions with binding constant values 3.72 × 103 L mol−1 (for Pd2+) and 8.26 × 104 L mol−1 (for Ni2+). Binding constant values of Pd-L complex increased in the presence of drug molecules, thereby indicating the absence of interference. The pH tolerance of the probe was found to be in the range of 3–11 (for Ni2+) and 2–11 (for Pd2+). DFT/TDDFT studies performed on LH, [Pd(L)(CH3CN)Cl] and [Ni(LH)(H2O)(CH3CN)Cl2] in CPCM continuum solvation model in CH3CN, showed good correlation between calculated UV–Vis and experimental spectra.

Investigation of fluoride concentrations, water quality, and non-carcinogenic health risks of borehole water in bongo district, northern Ghana

Access to potable water is a significant concern due to the increasing global threat posed by fluoride contamination in groundwater sources. This study investigated the concentrations of fluoride (F−), the suitability of groundwater for human consumption, the physicochemical characteristics affecting the water quality, and non-carcinogenic adverse health risks to both children and adults in the Bongo district in Northern Ghana. The findings revealed that the groundwater had a mean pH, salinity, TDS, conductivity, and turbidity below the WHO guideline values with a mean fluoride concentration of 1.76 mg/L above the guideline limit of 1.5 mg/L. The study also found that there was no strong relationship between fluoride and the measured water parameters, which may be attributed to poor control of distribution, transport mechanisms, and sources. The WQI scores ranged from 42.62% to 70.72%, indicating that all borehole water samples were of good and excellent quality. The average chronic daily intake showed that children are often more exposed to the harmful impact of fluoride than adults. The average HQ > 1 indicates the probability of dental and skeletal fluorosis after continuous exposure over time in adults and children. The study recommends taking immediate action to mitigate high groundwater fluoride concentrations, implementing appropriate water management strategies, and raising public awareness of the health risks. These measures can guide future groundwater management practices and help policymakers address contamination and protect local communities.

EVALUATION OF WATER POLLUTION STATUS OF TRIYUGA RIVER IN UDAYAPUR DISTRICT, NEPAL

The present investigation has been conducted to assess the status of physiochemical and microbiological parameters to understand the present scenario of water quality at Triyuga River water at Belaka municipality of Udayapur district, Nepal. The temperature ranged from 180C to 200C, the TDS value ranged from 89 mg/L to 112 mg/L and were below the WHO guideline value of 1200 mg/L, the pH values of the surface water sources in the present study were found to be alkaline ranging above from 7.6 to 7.9 were found within the range of WHO guideline value of 6.5-8.5. Similarly the values of dissolved oxygen ranged from 6.4 mg/L to 10.4 mg/L and were above the WHO guideline value of 5 mg/L, the bicarbonate (HCO3) value ranged from 105 mg/L to 125 mg/L and were below the WHO guideline value of 125-350 mg/L, the values of Nitrate ranged from 3 mg/L to 5 mg/L and were below the WHO guideline of 50 mg/L, the values of Nitrite ranged from 0.3 mg/L to 0.5 mg/L, the value of Ammonium ranged from 0 mg/L to 0.3 mg/L, the values of Iron ranged from 1 mg/L to 1.5 mg/L and were above the WHO guideline of 0.3 mg/L and the phosphate was not detected in all the three different sites of surface water samples. The fecal coliform was found to be positive in all the samples and the value of fecal coliform recorded was 15, 15 and 21 MPN/100ml in Site I, II and III respectively.

Identifying the source and fate of boron in geothermal water: Evidence from B/Na and B isotopes

High level dissolved B, which poses risks to human health, has been widely observed in geothermal water. In the Guide Basin, NW China, a series of geothermal water samples along a fault show a wide range of B contents ranging from 3.14 to 8.33 mg/L, which are higher than the WHO Guideline value equaling 2.4 mg/L in drinking water. To identify the sources and fate of B, we conduct a comprehensive analysis of hydrochemistry and stable isotopes (D, 18O and 11B) of three thermal fields representing three stages of hydrogeochemical evolution (stages I, II and III). From stage I to III, there are trends of increasing mineral dissolution, which is supported by increasing mean reservoir temperature and concentrations of conservative elements (Cl, Na, K, Li and Si). Geothermal water in stage I with meteoric origin and the lowest reservoir temperature has the highest B/Na resulting from silicate dissolution and falls on the mixing line between granitoids and cold water on the plot of δ11B versus 1/B, showing the control of silicate dissolution. However, geothermal water in stage III has lower Ca, B Sr and B/Na than that in stage II. Because of the occurrence of other processes, geothermal water in stages II and III deviates from the LMWL. Compared with geothermal water in stage I, the increased Sr/Ca and decreased B/Ca show that B are removed by both coprecipitation and vapor separation. With the aid of B isotopes, we find vapor separation dominates in stage II, whereas carbonate precipitation dominates in stage III. Overall, a combined use of three isotopes (H, O and B) and three element ratios (B/Na, B/Ca and Sr/Ca) leads to a complete understanding of B cycle and hydrogeochemical evolution in hydrothermal systems.

Kinetics, stoichiometry, and mechanism of arsenopyrite-water interaction under anoxic conditions

Arsenopyrite dissolution is an important source of arsenic’s environmental occurrence and is well-studied under oxidative conditions. However, little is known of anoxic leaching of arsenopyrite by water, though it is probably one of the dominant abiotic processes controlling arsenic mobility in oxygen-limited environments such as groundwaters and paddy fields. The present study attempts to probe the mechanism of arsenopyrite-water interaction in anoxic environment through examining the pH dependence of dissolution kinetics and stoichiometry, as well as speciation changes both on the surface and in solution. Batch and flow-through experiments were first carried out to measure dissolution rates and the results showed alkaline pH mildly encourages As release. Furthermore, the dissolution was found to be near stoichiometric with respect to As and S but not with Fe/As or Fe/S, and the non-stoichiometry exhibited a negative dependence on pH. Combining speciation analyses that revealed the presence of H2O2, SO42− and S2O32− in solutions and a positive correlation of surface species Fe(III)-O, S(-II), and As(I), As(III), As(V), and As(-III) to solution pH, we interpreted the anoxic dissolution behavior of arsenopyrite through a mechanism that combines surface complexation and interfacial redox reactions. The kinetic measurements came to be concerning as data indicates arsenopyrite dissolution in anoxic environment can lead to water having arsenic concentrations above the 10 ppb WHO guideline value in one day at the experimental conditions. The observed H2O2 production indicated the dissolution is associated with or initiated by electron transfer despite the anoxic condition, further suggesting that a more comprehensive theory other than surface complexation model may be needed to better understand the geochemical behavior of As and possibly S in the context of sulfide mineral–water interactions.

3.E. Workshop: Air pollution health impacts and costs in EU accessing countries

Abstract Air pollution is detrimental for health, climate, national economies and well-being in the European Union (EU) and in EU candidate countries. In many locations air quality levels are above the EU or national legal standards and/or the guidelines recommended by the World Health Organization. Very often EU neighbours and countries in the process of accessing the EU are disproportionately more affected by the impact of air pollution than others. The newest global evidence is suggesting that human health is affected even at low pollution levels below the current European standards and WHO guideline values. In 2021, the WHO published new air quality guidelines structured in Intermediate targets and final targets which are lower than the previous recommendations published in 2005. Estimating the costs of air pollution requires analysis of extensive data sets by means of econometric and statistical methodologies. In this session is discussed the assessment at country level for Europe and worldwide which is particularly valuable for estimating statistical value of life (VSL) and the value of a life year (VOLY) for counties that have not been the focus of global estimations so far. Moreover, this workshop adds valuable new information on the Western Balkans and Ukraine that could be used in systematic efforts to develop evidence-based air pollution reduction plans and to track progress toward reducing air pollution and consequently the health impacts. The studies included in this session represent valuable efforts to acquire evidence in support of further alignment of national air quality policies with those of the EU. Key messages • The newest evidence supports efforts to further aligning the Western Balkans and Ukrainian air quality policies with those of the EU and contribute to national and local implementation. • The meta-analysis of existing literature leads to the development of econometric models for estimating VSL and VOLY at country level worldwide.

Changes in ambient particulate matter exposure and evaluation of its health relevance in Germany

Abstract Introduction To evaluate the health relevance of fine particulate matter (PM2.5), it is necessary to assess the PM2.5 exposure of the populations. For this purpose, time series (2010-2021) for two PM2.5 indicators for Germany were developed: (1) the mean population-weighted PM2.5 exposure per year and (2) the proportion of the population exceeding the recent WHO air quality guideline value for PM2.5 of 5 µg/m3 (annual mean). Methods To calculate the two indicators for the period 2010-2021, nationwide modelled annual means of PM2.5 background concentrations were used. They were joined with spatial information on population density from the 2011 census. The population data were additionally scaled for each year according to the official population update. On this basis, the population could be assigned to different PM2.5 exposure classes per year. Results Over the years considered, the mean population-weighted PM2.5 exposure in Germany decreased by approximately 41 %: in 2021, the indicator value of 9.3 µg/m3 was significantly lower than in 2010 with 15.9 µg/m3. However, throughout the time series, almost 100 % of the German population was exposed to PM2.5 annual mean concentrations above the current WHO air quality guideline value. Conclusions Generally, the decreasing PM2.5 exposure of the German population is very positive. Measures taken in recent years to reduce emissions from stationary sources and the transport sector have contributed significantly to this development. On the other hand, the large proportion of the population above the WHO guideline value shows that the current annual average PM2.5 reduction is still far from being sufficient to protect human health. In fact, far-reaching measures are required to significantly reduce particulate matter concentrations in Germany. Key messages • The mean population-weighted particulate matter exposure in Germany has decreased significantly in recent years. • The exposure reduction in Germany is still not sufficient. To protect human health, further and far-reaching measures are required to significantly reduce particulate matter concentrations in Germany.

Water quality index, ecotoxicology and human health risk modelling of surface and groundwater along illegal crude oil refining sites in a developing economy

Water quality index, ecotoxicology and human health risk models were applied to surface and groundwater samples along illegal crude oil refining sites in Rivers State, Nigeria. Eight (8) surface water and four (4) groundwater sampling points were identified along illegal refining sites. Thirty-six (36) samples in triplicates were collected monthly from each of the twelve (12) sampling points over a three (3) month period. Water samples were collected and analyzed using standard methods as prescribed by the American Public Health Association. The mean pH for surface and groundwater ranged from 5.61 ± 0.15 to 7.34 ± 0.10 and 5.80 ± 0.10 to 6.39 ± 0.13, respectively. Turbidity, TDS, and BOD data for surface water samples exceeded the WHO guideline values. The ionic dominance pattern of anions for both surface and groundwater water samples were the same and in the order Cl− > SO42− > NO3− > PO42−. Mean heavy metal concentration was in the order Pb > Ni > Fe > Cd > Mn > Cu for surface water and Pb > Cd > Fe > Mn > Ni > Cu for groundwater. Cd and Pb concentrations in both sources were generally high, with Cd exceeding the WHO guideline value (GV). The CCME water quality index model ranked 62.5% of surface water as marginal, 12.5% as good, 12.5% as poor, and 12.5% as fair. The impact of heavy metals on public health was in the order Pb > Cd > Ni > Fe > Mn, with 83% of samples seriously affected by Pb pollution. The potential ecological risk index ranged from 1.61 × 103 to 2.64 × 103 for surface water and 8.10 × 102 to 2.21 × 103 for groundwater. Heavy metal contamination was very high, and the ecological risk effect was extremely high. The health risk through oral ingestion was in the order of adults > infants > children. Two principal components, PC1 and PC2, explained 50.51% and 16.00% of the variations in surface water quality, respectively. For groundwater quality data, three principal components explained the observed variations in water quality data, of which 51.39% is attributed to PC1, 26.29% to PC2, and 16.58% to PC3.

3‐Aminopropyl Triethoxysilane Capped ZnO Quantum Dots for Acrylamide Detection

AbstractAcrylamide (AA) is a carcinogenic, neurotoxin, and pregnancy‐harmful agent produced in food thermal processing. A specified excellent analytical technique performance is desired for detecting low AA concentration for human protection from its adverse impacts. A photoluminescent sensor APTES capped zinc oxide quantum dots (APTES/ZnO QDs) has been synthesized for AA quantification. Different capping agent's effects, for instance, triethanolamine (TEA), oleic acid (OA), tetraethyl orthosilicate (TEOS), polyvinyl pyrrolidone (PVP), 3‐aminopropyl triethoxysilane (APTES), and ethyl acetate (EA) on ZnO QDs are examined. The photoluminescence (PL) response of pristine ZnO QDs and APTES/ZnO QDs probe toward AA concentrations is investigated. This developed sensor exhibits selectivity as well as sensitivity for detecting AA ranging from 0.01 to 8.0 mM with a strong correlation coefficient (R2) of 0.9998 and a limit of detection (LOD) of 0.0019 mM, which is lesser than the WHO and European Union's guideline value. The possible photoluminescence enhancement mechanism of the APTES/ZnO QDs probe for AA detection is studied. Additionally, the reliability and performance of this facile, rapid, and precise analytical technique for quantifying AA in potato chip samples is confirmed and revealed satisfactory recoveries from 99.30 to 101.69% with relative standard deviations (RSD) from 1.4 to 1.6%.

Three-year monitoring of the efficacy and improvement of the most popular arsenic removal filter in Nepal

This paper presents the monitoring results of the arsenic removal efficacy of 27 Kanchan Arsenic Filters (KAF) in Nepal over a 3-year period. The average arsenic removal rate was 57%; however, 84% of the filtered water samples exceeded WHO guideline values. Arsenic removal capacities declined from over 90% to below 30% within approximately 1 year. Replacement of iron nails improved the arsenic removal capacities of two different testing groups by 10% and 23%, respectively, whereas changing all filter media, i.e., sand, gravel, and iron nails, with a limited budget of USD 17 per unit, improved the arsenic removal capacity by over 90% on average. The results of this study revealed that one reason for the reduced arsenic removal capacity of the KAF was the change in the type of iron nails used by the manufacturer, the substitution of non-galvanized with galvanized nails. An analysis of the different stages of the arsenic removal process using KAFs with already declined arsenic removal capacity revealed that the average arsenic removal rate from the supernatant to filtered water was −24%. In contrast, on average, most of the total iron (91%) from the supernatant water was removed from the filtered water. Based on these results, it was suggested that natural sand compounds may play a role in arsenic removal, and is recommended that the filter sand of the KAF be replaced every 3–4 months to maintain the effectiveness of the KAF in rural areas of developing countries, considering its maintenance and monitoring issues.

Quality of drinking water used by communities in selected villages from Iringa rural, Kongwa and Mufindi districts, Tanzania

Drinking water quality was assessed in selected villages from Kongwa, Mufindi and Iringa rural districts between March and August 2020. Ten villages from three districts were involved in the study: Kongwa (4 villages), Iringa rural (3 villages), and Mufindi (3 villages). Methods used in data gathering were observation, in-situ, and ex-situ measurement of water parameters. A total of 150 samples were collected from different water sources (a bore hole, a well, a spring, and a river) and analyzed using standard methods. Results show that the minimum and maximum values of dissolved oxygen (DO), biochemical oxygen demand (BOD, pH, total dissolved solids (TDS), turbidity, calcium, magnesium, fluoride, nitrate, and hardness were 3.35-9.62, 0.52-1.93, 4.40-8.28, 13.0-2000 mg/L, 0.47–31.6 NTU, 0.41-1.32 mg/L, 0.25-1.35 mg/L, 0.02-1.02 mg/L, 1.30-167 mg/L, and 0.68-216 mg/L, respectively. TDS (2000 mg/L) and nitrate (167 mg/L) were significantly higher than WHO guideline values in some villages from different sources. Further results indicated that 3 out of 17 sampling sites had Escherichia coli, indicating fecal contamination. Higher levels of physical-chemical parameters and microbial contamination observed are of health concern and call for mitigation measures. The study recommends regular water testing, monitoring its quality, treating source points, and providing education to communities surrounding the water sources.

Hydrogeochemical Evaluation of Groundwater for Drinking and Irrigation Purposes in Avudaiyarkoil Block, Pudukkottai District, Tamil Nadu, India

The purpose of this study is to evaluate the quality of groundwater for drinking and irrigation in the Avudaiyarkoil block of the Pudukottai district, which is a drought-prone region. Samples were collected from 20 wells on January 2021 and analysed for the water quality parameters, such as pH, EC, TDS, Ca2+, Mg2+, Na+, K+, Cl-, HCO3, SO4, NO3 and F-. The analysis revealed that SO4 is the dominant ion followed by Cl-, HCO3-, Na+, Ca2+, Mg2+, K+, NO3- and F- with respect to the mean value 292>234>208.4>125>100>24.75>18>16.15>0.2. The analytical results were compared with WHO and BIS guideline values to know the groundwater potability and TH, TA, SAR, Na%, RSC, PI, MgC and KI were calculated using the analytical results to identify the suitability of groundwater for irrigation purposes.

Identification of Critical Locations for Improvement of Air Quality Developing a Prioritized Clean Air Assessment Tool (PCAT)

Fourteen Indian cities, including urban and rural locations, were chosen for the present study across India, with unhealthy air quality based on National Air Quality Index (NAQI > 100). However, it was found that NAQI values over the locations are driven by the undifferentiated mass concentration of particulate matter (PM, both PM10 and PM2.5) than other criteria pollutants. The PM2.5 and PM10 concentration during the winter violated the National Ambient Air Quality Standards (NAAQS) of India by two to five times at six urban locations, with the mean daily PM2.5 concentration averaged over the month; the the largest being at Patna (353 µg m−3) during the winter and lowest at Bengaluru (27 µg m−3) during the summer. The analysis of chemical species, in general, indicated NO2 (SO2, CO) as having a 25% to 70% (16% to 50%, 16% to 85%) increase in concentration from the summer to winter, which is adequately reflected in higher fuzzy scores during the winter. Thus, to provide a realistic approach to air quality management, the present study focuses on identifying priority-based locations requiring immediate mitigation measures by developing a Prioritized Clean Air Assessment Tool (PCAT). The tool utilizes a fuzzy-based algorithm to incorporate the cumulative effect of all six criteria pollutants, taking into consideration the severity of their expected health implications. Using PCAT, Delhi and Varanasi cities are identified for prioritized mitigation considering the NAAQS of India, unlike all cities (except Bengaluru) during the winter and nine out of fourteen cities during the summer, considering the NAQI. Using more stringent WHO guideline values in PCAT, six cities out of fourteen were identified requiring immediate mitigation during the winter and summer months; locations such as Solapur and Patna are identified to need season-specific mitigation measures during the summer and winter, respectively. The tool is simplistic, user-friendly, and quickly evaluates multiple locations simultaneously to provide priority sites.

Hydrogeochemical characterization of ground and surface water in the eastern part of the Adamawa-Yade domain, Bertoua-Cameroon

Groundwater and surface water are major sources of water supply to the inhabitants of Bertoua. Hydrogeochemical study conducted in the study area aimed at identifying the processes that control the chemistry of groundwater sources and to examine the quality of the water sources for domestic and agricultural purposes. Fifty water samples were collected from boreholes, open wells, springs, and rivers within the study area in January 2022 (the dry season). The samples were analyzed for physicochemical characteristics including pH, electrical conductivity (EC), total dissolved solids (TDS) and major ions. The water samples were acidic with 94% of pH values less than 6.5. The EC varied from 21 to 776 µS/cm and TDS (8.5–388 mg/l). The low EC and TDS indicate low mineralization and fresh water. The relative abundance of major ions (meg/l) was Ca2+> Mg2+> K+>Na+ for cations and {text{H}text{C}text{O}}_{3}^{-}>Cl−>NO3−>SO42− for anions. These major ions concentrations were low and within the WHO guideline values for drinking water. From Piper diagram three water facies were observed; Ca-SO4, Ca-HCO3 and mixed Ca-Mg-Cl. Rock-water interaction, ion exchange, silicate weathering and anthropogenic activities were the processes responsible for the groundwater chemistry with some minor evaporative effects. Based on Sodium Adsorption Ratio and Residual Sodium Bicarbonate all samples fall in the excellent category for agriculture.