Drinking Water Quality Research Articles

Exploring tectonic sites with radon from groundwater sources and dose evaluation in various age groups in Baramulla, J&K, India

Maintaining water quality is essential to protect human health from elevated levels of radon, a water-soluble radioactive gas that can pose serious risks when levels are above safe thresholds. This study evaluated the radon levels in groundwater sources in the Baramulla district of Jammu and Kashmir using a scintillation-based smart RnDuo detector. The levels of radon showed significant fluctuations, ranging from 19 ± 0.7 to 93 ± 1.5 Bq L−1, with an arithmetic mean of 41.3 ± 1.0 Bq L−1. Notably, 51 % of the samples exceeded the limits set by USEPA (11 Bq L−1) and UNSCEAR (40 Bq L−1), yet all of them remained below the WHO's guideline of 100 Bq L−1. Furthermore, 13 % of the samples exceed 60 Bq L−1. Annual inhalation and ingestion doses vary across age groups surpassing the WHO recommendations for drinking water quality but lying below the UNSCEAR 1000 μSv y−1 suggested levels. Importantly, the mean annual effective dose throughout all age groups falls well below the ICRP range (3–10 mSv y−1). The analysis suggested that radon exposure could lead to 0.52 to 3 excess cancer cases per thousand people, with average values for all age groups remaining less than the permitted value of 1.45 × 10−3 as suggested by UNSCEAR. The study also explores physiochemical parameters, aiding future epidemiological studies and fault investigations.

The Impact of Pit Latrines on the Pollution of Groundwater in the District of Rwamagana, Rwanda

The composition and condition of a water body change over time and across different locations due to internal and external factors. In many rural and peri- urban communities in Rwamagana, the lack of treated water has increased reliance on groundwater for various household and community needs. Groundwater sources are essential for meeting the water demand in these regions. An investigation was carried out in the Rwamagana district of the eastern province of Rwanda to evaluate the influence of pit latrines on groundwater quality. The research examined the water quality of four boreholes with hand pumps and 18 improved springs located near pit latrines. The evaluation specifically looked at total coliforms (TC), electrical conductivity (EC), turbidity, and pH. The proximity of the pit latrines to the boreholes or springs was considered in order to determine the presence of fecal coliforms in the groundwater, with the goal of establishing a minimum safe distance between the pit latrines and water sources. The physicochemical indicators of the water samples met the drinking water quality criteria set by the World Health Organization (WHO). However, the levels of biological contaminants exceeded the WHO's drinking water quality standards. The highest coliform counts detected in the study were 99cfu/100ml of water. The research findings suggest a clear relationship between fecal microbes from pit latrines and their impact on groundwater quality, with the contamination effect extending up to 322.4m for improved springs and 266.2m for boreholes with hand pumps.

Groundwater quality and health risk assessment of nitrate and fluoride in Al Qaseem area, Saudi Arabia

Abstract Groundwater serves as the lifeline in arid regions, where aquifer overuse and climatic factors can substantially degrade its quality, posing significant challenges. The current study examines the drinking water quality in the Al Qaseem area and assesses the potential health risks from nitrate ( NO 3 − {\text{NO}}_{3}^{-} ) and fluoride (F−) exposure to infants, children, and adults. This evaluation employs parameters such as the daily water intake, hazard quotient, and non-carcinogenic hazard index. Groundwater samples from 38 wells and boreholes were analyzed for major cations and anions. The water quality index and multivariate tools were utilized. The average concentrations of SO 4 2 − {\text{SO}}_{4}^{2-} , Cl–, Ca+, Na+, Mg2+, and K+ exceeded acceptable limits. Among the 38 samples, 8 were unsuitable for drinking, with 5 categorized as very poor quality, 10 as poor, 14 as good, and 1 as excellent. Nitrate levels ranged from 1.30 to 108.00 mg/L, with a mean of 36.56 mg/L. Three wells exceeded World Health Organization (WHO) guidelines (50.00 mg/L). Fluoride ranged from 0.10 to 0.98 mg/L, with a mean of 0.71 mg/L and none surpassing WHO recommendations (1.5 mg/L). The HI values for adults, children, and infants were 0.993, 2.606, and 2.78, respectively. About 57.89% of the water samples exceeded the safety level of 1 for adults and 94.73% for both children and infants. Thus, the groundwater in the study area may pose non-carcinogenic health risks to infants, children, and adults when used as drinking water.

Groundwater potability assessment through integration of pollution index of groundwater (PIG) and groundwater quality index (GWQI) in Linggi River Basin, Negeri Sembilan, Malaysia

Groundwater acts as a natural insurance in ensuring sustainable freshwater supply for multiple sectors, as well as drinking water for 2.5 billion people globally. In Malaysia, Kelantan, Perlis, and Negeri Sembilan have shifted to groundwater as a freshwater alternative to combat existing water scarcity issues. Multiple sectors in Malaysia such as domestic (60%), industrial (35%), and agricultural (5%) sectors utilise groundwater to ensure economic progression. Aligning with the 6th Sustainable Development Goal (Clean Water and Sanitation), this study aims to assess the overall groundwater quality, factors controlling the groundwater hydrochemistry, and its suitability for drinking purposes. In this study, 108 groundwater samples (dry and wet seasons) were collected along the Linggi River Basin for the determination of physicochemical parameters, followed by the application of statistical analyses (principal component analysis (PCA), hierarchical cluster analysis (HCA), Pearson's correlation), as well as drinking water quality assessments (pollution index of groundwater (PIG) and groundwater quality index (GWQI)). The PCA indicated that weathering of rocks influenced the groundwater hydrochemistry the most, followed by agricultural practices, intrusion of seawater, and dissolution of ions. The Piper plot exhibited the occurrence of seawater intrusion due to the transition of groundwater type from Ca–HCO3 to Ca–Cl water type and Na–Cl during the wet season. Stations BH12 (PIG: 8.54, GWQI: 1034.55) and BH13 (PIG: 6.97, GWQI: 952.55) experienced high contamination from their respective PIG and GWQI values during the wet season. The HCA justified the classification of these polluted stations during the wet season by dividing the polluted stations into a separate cluster (Cluster II). Overall, the outcome of this study indicates that groundwater quality during the wet season is more polluted than in the dry season. As a precaution, it is advisable to treat the groundwater in Linggi River Basin before further consumption.

Implementation Of Water Quality Index For Measuring Groundwater Quality

Groundwater is one of the major sources of water consumption in developing countries. The aim of the study was to investigate the variations in physicochemical characteristics and metal content and to calculate the Water Quality Index (WQI) to assess the groundwater quality of seven districts (Central, East, West, South, Malir, Korangi, and Kemari) of Karachi City, Pakistan. A stratified sampling approach was used to collect groundwater samples and turbidity, pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Nitrate-N, and arsenic concentrations were investigated to profile WQI. The physicochemical parameters from districts South, West, Korangi, and Kemari were as per APHA standards and found suitable for drinking purposes. EC and TDS were in ranges of (2660-3870μS/cm) and (1596-2322mg/L) exceeding the standard limits resulting in poor drinking water quality respectively in districts Central, Malir, and East. These districts fail to meet the APHA standards and become unfit for human consumption on the WQI scale. However, TSS and arsenic was not detected in any of the collected samples. The correlation matrix for the[1] correlation coefficient (R-value) of tested parameters with WQI indicated significant linear and high R-value among tested parameters. The statistical analysis showed that turbidity, pH, EC, TDS, and Nitrate-N have significant effects on WQI. EC and TDS showed a direct correlation with WQI (R=1.0) whereas turbidity significantly correlates with the presence of nitrate in drinking water (R=0.64). These findings help the decision makers to plan mitigation strategies for comprehensive water quality monitoring of the respective areas and ensure the availability of clean and safe drinking water to the public.

Identification and assessment of Critical parameters affecting drinking water quality: A case study of water treatment plants of India

Water-borne diseases are common in India and are mostly brought on by shortages and poor quality of potable water. Watercourses receive many effluents, generally residential sewage, due to inadequate sanitation and wastewater treatment. Hence, drinking water treatment plants (DWTPs) face difficulties in meeting the drinking water standards. The current study evaluated the water quality before and after the conventional drinking water treatment process. The water quality was analyzed every month from three major DWTPs in Guwahati, Assam, India for one year. The study showed significant variation in river water turbidity and pathogen levels. During monsoon, river water turbidity reached up to 470 ± 20 NTU, and an increase in pathogen concentration was observed during the dry seasons at low flow conditions. Many times, drinking water turbidity and MPN values exceeded the BIS guideline value in drinking water. The total organic carbon (TOC), one major precursor of disinfection by-products observed in treated drinking water, was found to be in a higher range in water before and after treatment. After treatment, the TOC of (3.25 ± 0.5 mg/L) was found. For better understanding, the water quality was evaluated using the Modified Entropy-weight Water Quality Index (MEWQI) which showed very poor status in the raw water collected from the river Brahmaputra. While the plant's water quality after treatment varied in the category of fair to very good in certain months of the year, but never excellent quality was achieved in any of the selected plants. The results of the sensitivity analysis suggest that turbidity and MPN exhibit the greatest contribution to the WQI of raw water followed by TOC in drinking water. By providing accurate water quality data, this study benefits researchers, policymakers, and water scientists. It also facilitates the adoption of clean production methods to mitigate pollution and enhance water quality.

Geographic Information Systems for Water Quality Modeling in the Zhytomyr District Communities

Abstract To ensure safe and quality drinking water for residents of rural settlements who use their own wells, boreholes, and natural sources for domestic water supply, a comprehensive approach to evaluating the quality of underground drinking water using geographic information system (GIS) technologies is necessary. The purpose of the study was to assess the quality of drinking water sources of noncentralized water supply in rural settlements of the united territorial communities (UTCs) of Zhytomyr district and to create geoinformation models based on the research results. The following research methods were used during the research: analytical, field, laboratory, statistical, calculation, and cartographic. The research was conducted in 129 settlements of 12 UTCs of Zhytomyr district, where drinking water samples were collected from noncentralized water supply sources for further analysis in the Measurement Laboratory of Polissia National University, and the creation of geoinformation models using the ArcGIS Pro software package. It has been proven that the average pH level in none of the studied settlements exceeded the norm. The average nitrate concentration in the drinking water from noncentralized water sources exceeded the norm by 1.4–3.5 times, specifically in the water of the Pulyny, Cherniakhiv, Vilshanka, Volytsia, and Oliivka communities, exceeding the maximum acceptable concentration (MAC) limit by more than two times. Only in rural settlements in the Liubar community was the average iron content found to be above the norm by more than 1.9 times. Overall, it was established that the calculated value of the overall water quality class in the Zhytomyr district was 2.03, which is determined as “good,” clean water of acceptable quality. The best water quality was found in the Vilshanka, Cherniakhiv, and Stanyshivka communities, with a quality class range of 1.85–1.93, while the worst water quality was recorded in the Oliivka, Teterivka, and Liubar communities, with a quality class range of 2.13–2.31. It was determined that the highest contribution to the overall water quality was made by nitrate and iron content. The obtained research results and models based on them can be used by local governments of the studied communities to inform the population about the quality of drinking water and to develop a plan for improving the state of drinking water supply with the aim of increasing the level of environmental safety of drinking water.

Water pollution with fluoride in the Republic of Moldova and its impact on oral health

Water quality, especially drinking water quality, is one of the most essential requirements for the survival of not only mankind but all terrestrial life on Earth. As a determining factor of health, the quality of drinking water must correspond to sanitary regulations, and the violation of the water protection regime results in pollution. Water pollution is one of the major threats to public health in the Republic of Moldova. According to data compiled by the Yale Center for Environmental Law and Policy, globally, the Republic of Moldova was placed 83rd out of 180 countries in terms of drinking water quality, the first place being occupied by the countries with the highest drinking water quality. The „age-standardized life-years lost per 100,000 people due to exposure to unsafe drinking water (Daily rate)” is a measure used to evaluate the quality of water. The Daly score for the Republic of Moldova in 2022 was 50.0. The Republic of Moldova is considered a biogeochemical zone with regard to some chemical elements in the environment, including the content of fluorine in groundwater, soil, and subsequently in food products. The analysis of water samples taken by the National Public Health Center of the Republic of Moldova demonstrated that in 90% of cases, water sources subjected to laboratory investigations for microbiological and chemical parameters (boron, fluorine, and nitrates) do not meet the requirements. The present study was a prospective, observational one, the main objective of which was to evaluate the epidemiological dental characteristics of children from the fluorosis-endemic area of the Republic of Moldova. The study targeted 520 12- and 15-year-old children from Fălești district, where the fluoride concentration in drinking water exceeds 16 times the permissible norm of 16.2 ppm/l. Thus, the prevalence of dental fluorosis in this locality (Dean index ≥1) was 98.7 for 12-year-old children and 100% for 15-year-old adolescents. The prevalence of dental caries was 51.2% with an intensity of 2.1 for 12-year-old children, and for 15-year-old children, the prevalence was 67.1% with an intensity of 3.5. Children’s age and severity of dental fluorosis were independent predictors of dental caries intensity. Thus, a positive correlation was established between the severity of dental fluorosis and the intensity of dental caries in both study groups and in all groups of teeth. The percentage of children with a COAD index (decayed, filled, or absent teeth) ≥1 was higher in those whose Dean index was ≥ 5 in the second molar compared to other groups of teeth. Conclusion. Dental fluorosis remains the most common dental disease in fluorosis-endemic areas, and the severity of fluorosis increases with increasing fluoride concentrations in drinking water. Contrary to the previously established opinion, tooth decay also develops in children from endemic areas of fluorosis, and its frequency and intensity are directly correlated with the concentration of fluoride in drinking water. The higher the concentration of fluoride, the higher the values of the prevalence indices and intensity of dental caries. Republic of Moldova performs suboptimally in the prevention of oral diseases in the pediatric population, and the implementation of dental disease prevention programs would have major implications for improving dental morbidity.

The Impact of Extreme Hydrological Events on Drinking Water Quality in Rural Areas – Case Study South-eastern Serbia

The Impact of Extreme Hydrological Events on Drinking Water Quality in Rural Areas – Case Study South-eastern Serbia

Health risk assessment of arsenic and lead contamination in drinking water: A study of Islamabad and Rawalpindi, Pakistan

ABSTRACT The present research study explores the drinking water quality of Rawalpindi and Islamabad to identify the potent dissolved contaminants and carry out a health risk assessment as the study area houses more than 3 million people. A total of 95 drinking water samples were collected from the union councils of the selected study area and analyzed for 12 physicochemical water quality indicators. The collected datasets were interpreted using general statistics, principal component analysis and spatial analysis for knowing the variations among the collected samples. The results revealed that overall 51.57% of the drinking water samples were unsatisfactory for human consumption. The rate of physicochemical contamination was 87.27% in the rural and unauthorized housing societies. Arsenic (As) and lead (Pb) were the potent contaminants in the drinking water samples. The health risk assessment uncovered that 31.57 and 10.45% of samples had a hazard quotient (HQ) >1 for arsenic and lead, respectively. Collectively, 41 drinking water sources were identified as potential health risk sources for the residents.

Performance evaluation of the compact water treatment system pilot project at Timah Tasoh Water Treatment Plant, Perlis, Malaysia

Abstract Clean water is crucial to ensuring the well-being of people. The Package Timah Tasoh Water Treatment Plant (WTP) is designed to support the existing conventional plant in coping with the growing demand for clean water. The package plant used the Compact Water Treatment System, classified as a Category B in the Suruhanjaya Perkhidmatan Air Negara (SPAN) guidelines; thus, this performance monitoring research was conducted prior to product registration. The plant consists of aeration, flocculation, clarification, and filtration processes. The performance of this package plant was monitored through comparative and efficiency analysis of removal parameters and carried out over a period of six (6) months. Twelve (12) water quality parameters were selected, including turbidity, pH, total dissolved solids (TDS), colour, ammonia, residual chlorine, aluminium, iron (Fe), manganese (Mn), fluoride, standard total coliform, and E. coli with sampling water of RW, SW, FW, and TW, which was then assessed alongside the drinking water quality standards set by Ministry of Health (MOH). As a result, eight key parameters such as pH, turbidity, colour, TDS, iron, aluminium, manganese, and ammonia were meeting the MOH drinking water quality standards in over 94 % of cases. The remaining parameters are chlorine residual, fluoride, E. coli and standard total coliform were in non-compliance due to the inoperability of disinfection and fluoridisation processes. Most of the significant parameters deduced a better performance in terms of removal efficiency (> 60 %) consistently, except for TDS, throughout the monitoring activity.

Groundwater Hardness and Alkalinity As Risk Factors for Kidney Stone Disease in Alwar, India: An Ecological Study.

Rajasthan is a semi-arid state in India where people still use groundwater for drinking purposes. However, the quality of groundwater as compared to standards have not been studied in any details. This ecological study was done to study the groundwater quality parameters in the stone-belt states, compare the quality of groundwater in Alwar with the rest of Rajasthan, and study the morbidity profile of surgical in-patients in the same district, with special emphasis on kidney stone disease (KSDs). The morbidity profile of patients coming to the surgery department of a tertiary teaching hospital between January 2002 and June 2023 was obtained from the medical records department, and water quality data was obtained from the publicly available Water Resources Information System (WRIS) groundwater dataset for the year 2023. The dataset provided detailed information on the chemical parameters of water samples throughout the country that were evaluated to estimate the quality of groundwater. It was found that the groundwater in Alwar is non-potable due to the presence of iron, alkalinity, magnesium, and total dissolved solids (TDS). Iron was estimated to be much higher than the acceptable limit of the Bureau of Indian Standards (BIS) drinking-water quality guidelines (0.3 mg/L). Similarly, most of the chemical parameters in the groundwaters of Rajasthan significantly exceeded the national average. The median electrical conductivity, fluoride, magnesium, sodium, hardness, alkalinity, and turbidity were found to be 1680 μS/cm, 1.05 parts per million (PPM), 41 PPM, 233 PPM, 330 PPM, 310 PPM, 988 PPM, respectively, which are above the WHO recommendations for drinking water guidelines. The levels of iron and total alkalinity were significantly higher in the study district as compared to the rest of the state. Also, magnesium hardness and TDS levels were very high in the groundwater of the entire state of Rajasthan, making the population vulnerable to KSDs in the long run.

Bacteriological Examination of Drinking Water from Different Sites at a Tertiary Care Hospital Campus of Western India

Introduction: This study presents a detailed investigation into the drinking water quality at campus, focusing on various drinking water sources. Access to safe and clean drinking water is crucial for maintaining public health. In this study, we aimed to assess the drinking water quality at Bhaikaka University campus by collecting and analyzing drinking water samples from various sources. The research focused on identifying the presence of coliform bacteria, particularly E. coli, and evaluating the extent of contamination at different sites. Methodology: A total of 68 drinking water samples were collected from diverse drinking water sources across the campus. The MPN technique was employed to analyze the samples for the presence of coliform bacteria. The sites included all the buildings from the campus of Bhaikaka University. Results: Out of the 68 drinking water samples, 12 samples (17.64%) tested positive for contamination, while 56 samples (82.35%) showed no contamination. The highest number of positive samples (5 out of 15) was observed at Hospital, indicating the need for targeted interventions. Conclusion: This study provides valuable insights into the drinking water quality at campus with the identification of specific sites with higher contamination rates allows for targeted interventions. Future research can build upon these findings to implement effective strategies for sustainable water management on the campus.

Low Cost Water Purification: Harnessing Adsorbents for Sustainable Treatment Solutions

Water is essential for life, yet millions lack access to clean drinking water. Low-cost treatment methods are crucial to ensure equitable access to safe water and prevent waterborne diseases in underserved communities. The study devised a 12-liter water filter utilizing pebbles, sand, and adsorbents biochar of Julifora, cashew nut shell and rice husk. Results demonstrated the filter's effectiveness in sustaining pH levels while reducing chloride, fluoride, hardness and alkalinity. Particularly noteworthy was the capacity of cashew nut biochar to efficiently adsorb chloride, fluoride, hardness and alkalinity as 27%, 37%, 38% and 43% respectively. This indicates its promising role as an adsorbent for water purification. The findings underscore the potential of the designed filter in improving drinking water quality by mitigating contaminants. Further refinement and optimization of the filter could enhance its efficacy in meeting stringent water quality standards, addressing the pressing need for accessible and safe drinking water globally.

Examining drinking water quality: analysis of physico-chemical properties and bacterial contamination with health implications for Shangla district, KhyberPakhtunkhwa, Pakistan.

A comprehensive understanding of water quality is essential for assessing the complex relationship between surface water and sources of pollution. Primarily, surface water pollution is linked to human and animal waste discharges. This study aimed to investigate the physico-chemical characteristics of drinking water under both dry and wet conditions, assess the extent of bacterial contamination in samples collected from various locations in District Shangla, and evaluate potential health risks associated with consuming contaminated water within local communities. For this purpose, 120 groundwater and surface water samples were randomly collected from various sources such as storage tanks, user sites, streams, ponds and rivers in the study area. The results revealed that in Bisham, lakes had the highest fecal coliform levels among seven tested sources, followed by protected wells, reservoirs, downstream sources, springs, rivers, and ditches; while in Alpuri, nearly 80% of samples from five sources contained fecal coliform bacteria. Similarly, it was observed that the turbidity level, total dissolved solids, electrical conductivity, biological oxygen demand, and dissolved oxygen in the surface drinking water sources of Bisham were significantly higher than those in the surface drinking water sources of Alpuri. Furthermore, the results showed that in the Alpuri region, 14% of the population suffers from dysentery, 27% from diarrhea, 22% from cholera, 13% from hepatitis A, and 16% and 8% from typhoid and kidney problems, respectively, while in the Bisham area, 24% of residents are affected by diarrhea, 17% by cholera and typhoid, 15% by hepatitis A, 14% by dysentery, and 13% by kidney problems. These findings underscore the urgent need for improved water quality management practices and public health interventions to mitigate the risks associated with contaminated drinking water. It is recommended to implement regular water quality monitoring programs, enhance sanitation infrastructure, and raise awareness among local communities about the importance of safe drinking water practices to safeguard public health.

Potable water boiling can induce havoc in the water quality management arena due to the presence of microplastics

Around 30 % of the world’s population lacks access to safe water despite being a critical factor that modulates the complex dynamics of ecosystems and societies. Efficient technologies to purify water to potable form are either inaccessible or economically not viable for the majority. Water poverty and scarcity can be potentially exacerbated by the recent, widespread detection of plastics in drinking water sources, tap water and groundwater. This can induce various emerging bottle necks in global drinking water quality management. One of the most affordable disinfection techniques practiced across the world is to boil the water. Plastic pollutants in potable water sources can pose emerging water quality management bottlenecks, including leaching additives and chemicals due to water boiling. Exposure to plastic leachates in drinking water can lead to potential health risks, including oxidative stress, cancers, endocrine disruption, cardiovascular diseases, and developmental effects. The current global drinking water scenario and the emerging impacts of plastic pollutants specifically micro- and nano-plastics in drinking water, are also enlisted. Further, evidence-based prospects for drinking water quality management and impacts on one health initiative in the wake of the presence of plastics are discussed. Monitoring and surveillance, improved water treatment, and infrastructure incorporating technological innovations explicitly focusing on plastic pollutants in drinking water can ensure sustainable management and mitigation of the ill effects to a satisfactory extent. The need for firm policy instruments, partnerships between various private and public stakeholders, and the judicious use and management of potable water are contented in this article, which will steer humanity and the earth system toward achieving one health mandate and a sustainable future.

The poverty of sustainability: behavioral choices of drinking water in Kenya and Germany

Worldwide countries are engaged in technological improvements, changes in legislation, economic incentives, strengthened administrative structures, and political strategies to allocate and distribute water among different sections of the population. These macro measures treat water as an object of social, cultural, and environmental production unit for distribution and allocation, distancing it from the micro behavioral practices of drinking water. The poverty of sustainability stems from the gap between macro instrumental measures and the inner human dimensions that determine the micro practices. This paper explores the disconnect between macro sustainability measures and the micro practice of drinking water choice among individuals and their motives in the city of Nakuru in Kenya and the state of North Rhine-Westphalia in Germany. Both Kenya and Germany have developed top-down policies with a fix-it mindset. Kenya aims to provide drinking water to its population through piped network technology despite being a water-scarce region with inadequate housing and governance. In contrast, Germany, which is rich in water resources with highly regulated governance arrangements, spends billions treating water to attain drinking water quality only for most citizens to buy bottled water to drink. Despite water resources being finite, both of these nations source additional water through instrumental approaches to satisfy the demands of the materialistic world. In this context, the challenge of overcoming the poverty of sustainability remains a topic of debate that can be ameliorated by complementing scientific approaches with nonscientific knowledge and practices.

Source-specific nitrate intake and all-cause mortality in the Danish Diet, Cancer, and Health Study

IntroductionNitrate and nitrite are naturally occurring in both plant- and animal-sourced foods, are used as additives in the processing of meat, and are found in water. There is growing evidence that they exhibit a spectrum of health effects, depending on the dietary source. The aim of the study was to examine source-dependent associations between dietary intakes of nitrate/nitrite and both all-cause and cause-specific mortality.MethodsIn 52,247 participants of the Danish Diet, Cancer and Health Study, associations between source-dependent nitrate and nitrite intakes––calculated using comprehensive food composition and national drinking water quality monitoring databases––and all-cause, cardiovascular disease (CVD)-related, and cancer-related mortality over 27 years were examined using restricted cubic splines within Cox proportional hazards models adjusting for demographic, lifestyle, and dietary confounders. Analyses were stratified by factors hypothesised to influence the formation of carcinogenic N-nitroso compounds (namely, smoking and dietary intakes of vitamin C, vitamin E, folate, and polyphenols).ResultsPlant-sourced nitrate intake was inversely associated with all-cause mortality [HRQ5vsQ1: 0.83 (0.80, 0.87)] while higher risks of all-cause mortality were seen for higher intakes of naturally occurring animal-sourced nitrate [1.09 (1.04, 1.14)], additive permitted meat-sourced nitrate [1.19 (1.14, 1.25)], and tap water-sourced nitrate [1.19 (1.14, 1.25)]. Similar source-dependent associations were seen for nitrite and for CVD-related and cancer-related mortality except that naturally occurring animal-sourced nitrate and tap water-sourced nitrate were not associated with cancer-related mortality and additive permitted meat-sourced nitrate was not associated with CVD-related mortality. No clear patterns emerged in stratified analyses.ConclusionNitrate/nitrite from plant sources are inversely associated while those from naturally occurring animal-sources, additive-permitted meat sources, and tap water-sources are positively associated with mortality.

Valuing drinking water quality after a PFAS contamination event: Results from a meta-analysis benefit transfer

Drawing upon an extensive body of valuation literature focused on water quality, this paper performs a meta-analysis benefit transfer exercise aimed at quantifying willingness to pay (WTP) for an enhancement in drinking water quality for households that have been directly exposed to Perfluoroalkyl Substances (PFAS) over recent decades in Italy. The analysis compiles metadata of 72 WTP estimates extracted from 40 previous valuation studies conducted in advanced economies. The benefit transfer is realized estimating a meta regression model (MRM) which includes both study design and socio-economic explanatory variables, according to the Weak Structural Utility Theoretic approach. To determine the most suitable MRM specification, a comparative evaluation of various model configurations is developed exploiting the Least Absolute Shrinkage and Selection Operator (LASSO) selection criterion, and assessing their predictive performances in terms of transfer error and explanatory power. The mean transfer error (MTE) and the adjusted R-squared of the preferred MRM are in line with past published meta-analyses (0.665 and 0.607, respectively). The parameters estimated in the model align with both economic theory and intuition. The benefit transfer process results in an estimated annual WTP of € 250.80 per household for improved drinking water quality in the PFAS-affected area and an aggregated value of social benefits from PFAS decontamination of around € 12 million.

Impact of leachate on groundwater quality using physicochemical characteristics

ABSTRACT This study assesses the impact of Koshe open dump site leachate on nearby groundwater quality. Groundwater quality is threatened by open dump sites. Groundwater samples around Koshe open dump sites showed elevated levels of various physicochemical characteristics, including Electrical conductivity (EC), Potassium (K), Iron (Fe), Chromium (Cr3), Lead (Pb), Mercury (Hg), Total Alkalinity, Nitrate (NO3−), Phosphate (PO4+), Cadmium (Cd), Bicarbonates (HCO3−), Arsenic (As), Salinity, Cobalt (Co), and Silicon (Si), exceeding Ethiopian, WHO, and EPA drinking-water quality standards. Among the sampled wells, the one located at Ayer Tena High School, upstream of Koshe, exhibited significantly lower concentrations of parameters indicating leachate impact on groundwater quality As, Cd, Cr3, Pb, Hg, Molybdenum (Mo), NO3-, K, and PO4+ compared to others. The presence of these parameters in nearby groundwater wells suggests a substantial impact of the Koshe dump site on groundwater quality. Traditional landfills and dump sites must be outlawed, and new hygienic landfills must be constructed in a convenient location to end the continued groundwater pollution.