Safe drinking water is defined as water that complies with health standards and can be consumed directly without posing a risk to human health. Adequate sanitation during water processing is crucial to prevent bacterial contamination, which may lead to illnesses such as diarrhea. In Indonesia, diarrhea continues to be one of the primary causes of mortality among children under five. This study sought to examine the relationship between hygiene and sanitation conditions at refill drinking water depots (DAMIU) and the bacteriological quality of the water produced in Kediri. An observational analytic approach with a cross-sectional design and saturated sampling was employed. Bivariate analyses were performed using the Chi-Square test, with Fisher’s Exact test applied when Chi-Square assumptions were not fulfilled. Of the 17 DAMIU assessed, 8 failed to meet the 2010 Ministry of Health bacteriological standards, which stipulate that acceptable drinking water must contain 0 E. coli and 0 total coliforms per 100 ml. Furthermore, 7 depots did not comply with required hygiene and sanitation standards. The analysis showed a significant relationship between DAMIU sanitation hygiene and the bacteriological quality of drinking water. Factors influencing contamination include water source, treatment process, sterilization tools, operator hygiene, and the treatment environment. This finding highlights the importance of maintaining sanitation hygiene throughout the refill water treatment process to ensure safe and bacteria-free drinking water.

Groundwater serves as the primary source of clean water for residents of Suka Damai Village, Muara Badak Subdistrict, Kutai Kartanegara Regency. However, laboratory analyses reveal severe microbiological and physicochemical contamination in both shallow dug wells and deep boreholes, exceeding the standards set by the Indonesian Ministry of Health Regulation No. 2 of 2023. This study aims to design a hybrid groundwater treatment system based on empirical laboratory data to produce safe drinking water. Water samples were collected from two strategic locations—a deep borehole and a shallow dug well—and analyzed at the Environmental Laboratory of DLHK Kutai Kartanegara. Results showed that raw water exhibits total coliform levels up to 6,488 MPN/100 mL, E. coli at 259 MPN/100 mL, total dissolved solids (TDS) of 704 mg/L (exceeding the 300 mg/L standard), turbidity of 47.6 NTU, and offensive odor. Based on these findings, a three-stage hybrid system is recommended: (1) aeration using an aeration tower, (2) multistage filtration (zeolite sand, manganese media, granular activated carbon), and (3) ultraviolet (UV) disinfection—deliberately avoiding chlorine to prevent the formation of carcinogenic disinfection by-products (DBPs), such as trihalomethanes (THMs). System sustainability is ensured through a governance model managed by the Village-Owned Enterprise (BUMDes) and supported by household willingness to pay (WTP) of IDR 50,000–150,000 per month. This research demonstrates that contaminated groundwater can be transformed into safe drinking water through an integrated approach combining appropriate technology, social engagement, and renewable energy.

Water Partnerships empower stakeholders to support locally-led decision making around the motivation, form, and sustainable management of a safe water system. While partnerships can support the long-term success of water systems, the forms of such partnerships are not yet well understood. This study learned about creating Water Partnerships from hundreds of water leaders on four continents: (1) who needs to be involved, (2) what are the roles of various partners, and (3) what tools ensure that everyone is confident and able to participate? Stakeholders and their roles are identified and recommendations are shared for each of eight steps in a participatory water process from ignition through participatory design, construction, and operations. Essential tasks involved aligning project goals, establishing roles and responsibilities, selecting a locally-appropriate water system design, developing a water action plan including financial management, operations and maintenance, accountability, and training for water leaders. These findings are critically assessed in the context of participatory frameworks including the Ladder of Citizen Participation. The appropriate level of citizen participation varied throughout the process: values-based decisions were made by community members, whereas informed decisions of science, health or operational nature were mostly taken after consultation with outside experts. Participants reported that participatory processes expanded their impacts by “multiplying ourselves into other community structures”. Effective partnerships require trust, which may be built through transparency, revealing one’s interests, and the ability to listen. The Water Partnerships approach is underlined by the quote: “ People understand their water challenges, and they know their water solutions too ,” which highlights the need to listen, to empower, and to integrate local knowledge.

Using machine learning to predict heavy metal concentrations and induced health risks in drinking water distribution systems from key cities in China.

Identification of priority management tributaries to protect drinking water sources in the Yangtze River mainstream: A novel framework based on simulated arsenic pollution incidents.

Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent synthetic chemicals with known toxicological effects, including endocrine and developmental disruption. Perfluorooctanesulfonic acid (PFOS), one of the most prevalent PFASs, can enter freshwater ecosystems via runoff and effluents, potentially transferring through food webs to humans. Freshwater pulmonate snails (family: Lymnaeidae) occupy a basal trophic position and may act as both PFOS bioindicators and contaminant vectors. We tested whether Stagnicola elodes snails could detect and behaviorally avoid PFOS at environmentally relevant concentrations using a Y-tube choice assay. Snails were given a choice between control water and PFOS solutions ranging from 4 to 2500 ng/L. Behavioral outcomes were classified as movement toward PFOS, toward control water, or no decision. Avoidance behavior was significant at 300 ng/L when excluding non-decision snails, and at 100, 300, and 400 ng/L when including them. These results suggest that S. elodes can detect PFOS within a narrow concentration range, but behavioral responses are modest and at levels above safe drinking water standards (∼4 ng/L), minimizing both their potential as a strong bioindicator species for PFOS contamination and their ability to limit trophic transport.

A large portion of the Nigerian population lack access to safe drinking water, leading many to depend on sachet water because it is affordable and widely available. This study evaluated heavy metals and trace elements concentrations in sachet water samples from various locations across Lagos State, Nigeria. A cross-sectional study was conducted on 29 sachet water samples from the 20 Local Government Areas of Lagos State. The concentrations of heavy metals and trace elements were measured using the Agilent 5800 Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) system. The samples were clear and debris-free on physical examination, NAFDAC registration numbers, product names, and manufacturing addresses were seen on their labels, however relevant information including batch number, expiry and production dates were not found among the information on the sachet water labels. Chemical analysis of the sachet water showed that the concentrations of lead, arsenic, uranium, and mercury exceeded WHO safety limits in 65.5%, 51.7%, 17.2%, and 3.5% of the samples, respectively. Other heavy metals and trace elements analyzed were within permissible limits. Most of the metals had hazard quotient values below 1, suggesting minimal health risks from these elements for both adult and children's consumers. Sachet water samples in the study area generally meet safety limits for heavy metal and trace element exposure, however, the presence of elevated levels of heavy metals in some samples and poor compliance with the laid down regulations for the sachet water labels calls for strengthened regulatory monitoring.

Nearly one-third of the global population lacks access to safe drinking water, with the unavailability of simple and efficient disinfection devices being a key contributing factor. Mercury lamps are effective, safe, and reliable UV-based disinfection devices, whereas their application is limited to regions with a stable power supply. Here, we design a manually operated triboelectric-electromagnetic hybrid generator able to power a UV mercury lamp. Combining the advantages of a triboelectric nanogenerator and an electromagnetic generator, this unit exhibits electrical output of variable impedance characteristics, matching the power requirement of UV mercury lamps. Powered with cranking or pedaling, enabled by our tailor-designed transmission system, the device achieves 8-log pathogen removal from 2 L of water in 25 min with cranking or 10 L in 15 min with pedaling. The latter is sufficient to meet the daily drinking water needs of a family of four set by the World Health Organization. With a low capital cost, this grid-free UV disinfection system could potentially provide safe drinking water, at a levelized cost of 8.57 USD/(capita·yr) to ∼1.8 billion people in over 375 million households in underdeveloped countries/regions, substantially contributing to the United Nations Sustainable Development Goal 6.

Water, sanitation, and hygiene (WASH) are foundational determinants of public health and community development. Globally, approximately 2.3 billion people still lack access to safe drinking water and sanitation services. These disparities are most pronounced in low- and middle-income countries such as Haiti, and regions affected by conflict, political instability, or fragile health infrastructure. An integrative review was conducted to evaluate the best practices in community health volunteers' training on WASH practice outcomes in underserved communities. A literature search was performed, including articles published between 2015 to 2025 in PubMed, CINAHL, and Embase. Whittemore and Knafl's method of integrative review was employed to ensure a rigorous approach for the review, and the Johns Hopkins Nursing Evidence-Based Practice appraisal tool was used for quality and grading. Nine studies were included in the review that involved CHV training interventions in underserved populations. Results were synthesized and interpreted using the COM-B behavioral change framework. Four themes were identified across the literature, which included (1) behavioral change, (2) knowledge and capability, (3) confidence and motivation, and (4) community engagement and opportunity, to promote successful community volunteer-led WASH training programs. Knowledge improved in most studies, but behavioral change was inconsistent. Given that the COM-B model supports that only one of the domains need to change to elicit behavior change, findings in this study suggest that building knowledge/capacity, or promoting opportunity, or encouraging motivation alone can be powerful. Recommendations from the literature support the implementation of community volunteer-led WASH training programs to improve overall knowledge and confidence among those engaged in WASH efforts. The recommendations are applicable to the context of WASH practices in Haiti, which remains sparse, especially in rural areas. Community-engaged research plays an integral role in how communities can embrace the behavior change necessary to achieve long-term improvements in hygiene and sanitation.

Physicochemical and bacterial contamination pose a significant threat to drinking water quality in Bangladesh, requiring comprehensive analysis. This study investigates the physicochemical and metagenomic quality of drinking water from one of four water treatment plants (WTPs) in Kushtia Municipality, Bangladesh. Water samples (n = 3) from untreated, treated, and supplied water were collected between March 1 and 7, 2025. Thirteen physicochemical parameters were analyzed using traditional methods, while bacterial load was assessed using Plate Count Agar. Microbial diversity was analyzed through metagenomic sequencing of DNA extracted using the DNeasy PowerWater Kit, targeting the 16S rRNA gene (V3-V4 region) on the Illumina MiSeq platform. Alpha and beta diversity were evaluated with Chao1, Shannon, and Simpson indices, and taxonomic and pathway analysis were performed on the Kaiju and Nephele platforms. Water quality was assessed using treatment efficiency metrics, the Water Quality Index (WQI), and the Nemerow Pollution Index (NPI). Results reveal that only three of the physicochemical parameters meet the water quality standards of Bangladesh. The WTP's cumulative efficiency metric was found to be 30.76%. The WQI indicated that all water samples were unfit for drinking. The NPI showed that eight out of thirteen physicochemical parameters significantly contribute to poor water quality. Microbial evaluations revealed high bacterial levels in untreated and supplied water samples. Alpha diversity analysis, using Shannon and Simpson indices, showed no significant differences in bacterial abundance across water types. Beta diversity analysis indicated minimal dissimilarity. Functional profiling suggested the presence of antibiotic resistance-associated pathways, with predicted beta-lactam resistance representing 24.1% in treated water and 25.0% in supplied water. The dominant phyla include Proteobacteria (38% in untreated, 39% in treated, and 42% in supplied). About 75%, 83%, and 67% of the identified bacterial species were found to be pathogenic, antibiotic-resistant, and biofilm-forming, respectively, while 58% were classified as opportunistic pathogens. These results underscore the need for improved water treatment practices and more robust monitoring systems to ensure the population can access safe drinking water.

Access to safe drinking water remains a major challenge in sub-Saharan Africa, where reliance on unimproved water sources exposes millions to waterborne diseases and undermines progress toward Sustainable Development Goal 6 (SDG 6). Understanding spatial patterns and determinants of unimproved water use is essential for targeting WASH interventions. We analyzed data from 500,845 households across 20,492 clusters in 34 sub-Saharan African countries using Demographic and Health Surveys (2012-2024). Data was processed using Microsoft Excel and STATA version 17. Prevalence estimates accounted for the DHS complex sampling design. Spatial analyses (Global Moran's I, Getis-Ord Gi*, SaTScan™, Anselin Local Moran's I) and Geographically Weighted Regression (GWR) were conducted to identify clusters and key predictors. Overall, 58% (95% CI: 51%-65%) of households relied on unimproved drinking water sources. This indicates that approximately three in five households utilize unimproved water source. Significant spatial clustering was detected (Global Moran's I = 0.2415, p < 0.001), with major hotspots in Madagascar, Uganda, Rwanda, Mozambique, Malawi, Chad, Nigeria, Togo, Burkina Faso, Liberia, Sierra Leone, Mali, Ethiopia, parts of Angola, the Congo Republic, Zambia, and Zimbabwe. SaTScan™ identified 109 significant clusters, and Local Moran's I revealed mixed high- and low-risk zones. GWR (adjusted R² = 0.917) highlighted key predictors: rural residence, female-headed households, older household heads (50 + years), poverty, limited media exposure, lack of electricity, and poor water access. Unimproved water use remains widespread and spatially concentrated across sub-Saharan Africa. The determinants identified by GWR poverty, rural residence, limited infrastructure access, and low household media exposure highlight critical inequities driving this burden. Addressing these disparities requires localized, data-driven WASH planning that prioritizes hotspot regions, expands access to affordable improved water systems, strengthens electricity and media outreach infrastructure, and supports vulnerable households. Implementing these targeted and multi-sectoral strategies is essential for accelerating equitable progress toward SDG 6 and improving public health resilience across the region.

Solar water disinfection (SODIS) is an emerging, sustainable method for improving water quality in regions facing limited access to safe drinking water, including the Middle East and North Africa (MENA). SODIS has been applied to a wide range of microorganisms, which show varying levels of sensitivity to the treatment. Dormant forms, such as spores and cysts, are typically more resistant to inactivation, while bacteria are, in general, more susceptible and can be inactivated within 1 h, depending on solar irradiance intensity. The higher the solar radiation, the faster the inactivation process. Virus inactivation by SODIS follows a pattern similar to that of bacteria, although MS2 bacteriophage is more resistant than both bacteria and other viruses. While some microorganisms require extended exposure times (up to 6 h), certain additives or methods can significantly reduce the time needed for effective disinfection. For example, hydrogen peroxide (H 2 O 2 ), which forms via reactive oxygen pathways, acts as an oxidative agent, damaging DNA and contributing to the inactivation process. Singlet oxygen (1O 2 ), a key reactive species, is responsible for oxidizing proteins and breaking down DNA and RNA strands, leading to microbial cell death. Overall, SODIS is an effective, low-cost, and simple method for pathogen inactivation, requiring minimal skills and equipment, making it particularly useful in disaster-stricken areas such as those affected by earthquakes or other natural disasters. Its accessibility and effectiveness make it particularly valuable in disaster-stricken areas and resource-limited settings, providing a practical strategy for reducing waterborne disease risks in the MENA region.

Many Americans distrust tap water, leading them to purchase more expensive drinking water sold from water vending machines (e.g., kiosks) that are poorly regulated and sparingly monitored for quality. Here, we analyzed the water quality of 20 kiosks from 4 different manufacturers across 6 states in the first comprehensive comparison of the chemical and microbial characteristics of kiosk water to paired tap samples. Of the 16 kiosks listing specific water treatment processes (others indicated "filtered" or "purified"), only 1 dispensed water with ionic composition (e.g., Na+, Ca2+, Mg2+) inconsistent with the stated treatment. Most kiosks tested used reverse osmosis (RO), which removed fluoride and residual disinfectant, although we found no evidence of microbial contamination. RO also provided the benefit of removing per- and polyfluoroalkyl substances. However, we frequently detected higher lead levels in kiosk water than in nearby tap water. Lead was detected (>0.05 μg/L, our method detection limit) in 15 kiosks; 5 were >1 μg/L (American Academy of Pediatrics recommendation), 2 were >5 μg/L (FDA allowable level for bottled water), and 1 was >10 μg/L (US EPA Action Level). Lead co-occurred with zinc and copper, consistent with corrosion of lead-containing plumbing materials. XRF analysis of plumbing in 2 kiosks from different manufacturers with nationwide distribution confirmed this suspicion although all components in question met the definition of lead free under the Safe Drinking Water Act. Lead release was most evident with the use of RO treatment, which can produce corrosive water low in alkalinity and pH. Going forward, the removal of lead-containing plumbing components downstream of RO treatment and regulation with routine testing of kiosk water quality is imperative to address this unchecked public health risk.

Access to safe and clean drinking water is a key determinant of public health and well-being. This study explores the relationship between perceived unpleasant odor of tap water (as a proxy of water quality) and perception of health risks from tap water, in low- and middle-income areas of Mexico, emphasizing the role of perceptions shaped by sensory indicators such as taste, color, and odor. The connection between perceived unpleasant odor of tap water and perceived risk warrants attention as a public health concern, given its potential to influence consumer behavior, risk exposure, and trust in health-related products and services. The analysis draws on household survey data collected through face-to-face interviews in Zapopan, Jalisco, Mexico, in October 2018, complemented with a review of existing literature. Statistical regression models were executed to assess the association between perceived water quality and perceived health risk from drinking tap water. The analysis shows that households perceiving an unpleasant odor in tap water had 29% higher odds of identifying it as a health risk (OR = 1.29), controlling for socioeconomic and demographic conditions. The findings underscore the need for public health interventions that address both actual and perceived water quality. Integrated water policies should prioritize equity, strengthen community trust, and incorporate engagement strategies to mitigate health risks linked to water insecurity.

Access to safe drinking water in rural areas remains a global challenge, particularly where decentralized supply systems are common and water quality is highly variable. In this study, we analyze the relationship between the chemical composition of drinking water and community perceptions of its quality in rural settlements of the Akmola Region of Kazakhstan across different landscape types. Using a mixed-methods approach, hydrochemical analyses of household water samples were conducted, ANOVA and Spearman correlation tests were applied, and village-level survey data were collected to assess the complaints, satisfaction, and water purification practices of residents. Results indicate that most water sources are of Ca–Mg–Cl–HCO 3 type, with steppe villages showing higher levels of dissatisfaction. These findings highlight the importance of aligning technical water assessments with local perceptions to improve rural water governance and foster community trust in water safety initiatives.

Long-term Prediction of Saltwater Intrusion Based on Sequence Learning Framework.

Access to safe drinking water is essential for public health, especially in rural communities that depend on alternative water supply sources such as boreholes. This study aimed to characterize the quality of water supplied from boreholes in the community of Nicuapa, in the district of Montepuez, Mozambique, by evaluating physical and chemical parameters and comparing the results with the standards established by Mozambican Decree No. 18/2004 and the guidelines of the World Health Organization. Five water samples were collected at different points within the community and analyzed at the Environmental Quality Control Laboratory of Moz Environmental – Pemba. The evaluated parameters included pH, turbidity, total suspended solids, chemical oxygen demand, nutrients, phenols, inorganic ions, and electrical conductivity. The results showed that, at most sampling points, the water presented physicochemical quality within the legal limits, indicating suitability for human consumption. However, the sample collected at the point located outside the school showed elevated values of turbidity, total suspended solids, and phenol, suggesting possible localized contamination. It is concluded that, although borehole water in Nicuapa is generally adequate, spatial variations in water quality exist, highlighting the need for regular monitoring and improved sanitary protection of the sources to ensure a safe and sustainable water supply for the population.

Vertical migration of multi-source nitrates driven by multiple water inputs in groundwater based on combined nitrogen-oxygen and hydrogen-oxygen stable isotopes.

Arsenic (As) and fluoride (F⁻) in groundwater limit access to safe drinking water across East Africa, yet process-based understanding of their co-occurrence in Precambrian basement aquifers of northern Tanzania remains limited. This study analyzed groundwater samples (n = 88) from 13 wards in Geita district, Lake Victoria Basin, adjacent to large-scale and artisanal gold mining areas. An integrated approach combining hydrogeochemistry, geospatial analysis, and geochemical modeling was used to investigate spatial variability and the hydrogeochemical processes controlling the distribution of As and F⁻ in the aquifer. Arsenic concentrations ranged from 2.5 to 280 μg/L and F⁻ from 0.13 to 2.17 mg/L; with approximately 82% and 8% samples exceeding World Health Organization (WHO) guideline values, respectively. Groundwater pH was 5.7–7.5, electrical conductivity (EC) and total dissolved solids (TDS) indicated generally acceptable salinity and dissolved As occurred predominantly as As(V) species. As and F⁻ exhibited spatial clustering and co-occurrence associated with migmatite-granitoid-metasediment complexes and volcano-sedimentary Greenstone Belt lithologies, with higher concentrations observed in mining-affected areas. These patterns are interpreted within a Critical Zone framework, where coupled lithological, hydrological, and biogeochemical processes regulate weathering reactions, generate reactive Fe-oxide and clay surfaces, and establish pH and redox conditions that control trace element mobility. Variations in pH (5.7–7.5) influenced As mobility primarily through oxidative weathering of arsenopyrite and other sulfides, forming secondary Fe(III) oxides and hydroxides. Subsequent reductive dissolution of these Fe phases under favorable geochemical conditions released sorbed or co-precipitated As into groundwater, particularly within Ca-HCO3 type waters. Fluoride mobilization was enhanced under alkaline, Na–HCO₃ waters, low Ca²⁺ activity, elevated Na⁺ and HCO₃⁻, ion exchange, and calcite precipitation, which together favored fluorite dissolution and desorption. By linking observed spatial patterns to Critical Zone weathering processes, this study provided a mechanistic basis for As and F⁻ co-occurrence in Precambrian basement aquifers of Northwest Tanzania and offered insights for groundwater-risk assessment and the design of safe drinking-water supply strategies in mining-affected regions.

The critical importance of access to water has been recognized both nationally and internationally. In the United States, the National Infrastructure Protection Plan and other planning documents highlight the potentially dire public health implications of impacts on public water systems. According to the Fifth National Climate Assessment, safe and reliable potable water supplies are at risk due to climate change, flooding, drought, and sea level rise, and such risks are expected to increase going forward. Internationally, the Sustainable Development Goals include ensuring availability and sustainability of water and sanitation. Despite this fact, acute shocks and long-term stressors may cause contamination or otherwise limit access to safe drinking water. The Federal Emergency Management Agency's Community Lifelines approach encompasses access to water and other necessities, and requires emergency managers to take a whole-community approach to response and recovery. However, preparedness and mitigation efforts have not historically taken this same approach. Recent water crises, such as the ones in Flint, Michigan, and Jackson, Mississippi, have shown a disconnect between water system managers and emergency managers. Inclusive emergency management demands consideration of both current and future needs, and consideration of Community Lifelines, regardless of the circumstances surrounding the adverse event. The recent saltwater intrusion threat along the lower Mississippi River in southeast Louisiana has provided yet another example of vulnerability in the drinking water sector and the intersection of emergency management and public health.