Search Results (112)

Background: Access to safe and reliable water and sanitation remains a critical public health and development challenge, with rural and low-income communities being disproportionately affected by inadequate services and heightened exposure to waterborne diseases. Despite global efforts and infrastructure-based progress indicators, significant disparities persist, and these often overlook users’ perceptions of water quality, reliability, and safety. This study explores the determinants of household satisfaction with drinking water in rural areas, comparing subjective user feedback with official access data to reveal gaps in current monitoring approaches and support more equitable, user-centered water governance. Methods: This study was conducted in Kazakhstan’s Atyrau Region, where 1361 residents from 86 rural villages participated in a structured survey assessing household access to drinking water and perceptions of its quality. Data were analyzed using descriptive statistics and multinomial logistic regression to identify key predictors of user satisfaction, with results compared against official records to evaluate discrepancies between reported experiences and administrative data. Results: The field survey results revealed substantial discrepancies between official statistics and residents’ reports, with only 58.1% of respondents having in-house tap water access despite claims of universal coverage. Multinomial logistic regression analysis identified key predictors of user satisfaction, showing that uninterrupted supply and the absence of complaints about turbidity, odor, or taste significantly increased the likelihood of higher satisfaction levels with drinking water quality. Conclusions: This study underscores the critical need to align official water access statistics with household-level experiences, revealing that user satisfaction—strongly influenced by supply reliability and sensory water quality—is essential for achieving equitable and effective rural water governance. Full article

Cadmium (Cd) pollution poses a serious threat to freshwater ecosystems. The freshwater mussel Anodonta woodiana is increasingly used as a bioindicator for monitoring Cd pollution in aquatic environments. However, the primary routes of Cd accumulation in A. woodiana remain unclear, and the molecular regulatory mechanisms underlying Cd accumulation are poorly understood. To address these gaps, this study employed a novel stable isotope dual-tracer technique to trace Cd from water (waterborne ¹¹²Cd) and the green alga Chlorella vulgaris (dietary ¹¹³Cd) during the simultaneous exposure experiment. Comparative transcriptomic analysis was then conducted to characterize molecular responses in A. woodiana following Cd exposure. The results showed that although newly accumulated ¹¹²Cd and ¹¹³Cd increased with exposure concentration and duration, the relative importance of ¹¹²Cd (91.6 ± 2.8%) was significantly higher than that of ¹¹³Cd (8.4 ± 2.8%) (p < 0.05). Cd exposure induced differentially expressed genes primarily enriched in the metabolic processes, cellular processes, and/or the ubiquitin-mediated proteolysis pathway. Within the ubiquitin-mediated proteolysis pathway, TRIP12 (E3 ubiquitin-protein ligase TRIP12) and Cul5 (cullin-5) were significantly upregulated. The findings will provide critical insights for interpreting Cd biomonitoring data in freshwater environments using mussels as bioindicators. Full article

Background: Non-cholera Vibrio species are rare waterborne pathogens that can cause severe infections. Among these, few cases of Vibrio metschnikovii infections have been reported, especially in the gastrointestinal tract, with no cardiac tissue involvement as a result. Following the PRISMA checklist, we conducted a literature review, and thirteen articles for twenty-two cases overall were included: seven cases of sepsis (in three cases, the echocardiographic results were negative), seven cases of pneumonia, two skin infections, eleven cases of diarrhoea, and a gastroenteritis outbreak. This report documents the expanding clinical spectrum and the role played by V. metschnikovii in infective endocarditis. Case report: A 28-year-old male patient was referred to the cardiac surgery unit for urgent mitral valve replacement due to suspicion of infective endocarditis. Microbiological tests yielded negative results. Following recovery and discharge with antimicrobial therapy for 6 weeks, the patient experienced prosthesis detachment, necessitating re-hospitalisation for an emergency valve replacement. Vibrio metschnikovii was identified on the prosthesis valve through PCR and successfully treated with ciprofloxacin. However, a spontaneous rupture of the ascending thoracic aorta led to a neurological injury. Discussion: This case represents the first case of valve infection caused by Vibrio metschnikovii, characterised by diagnostic and therapeutic challenges and the involvement of the great vessels. Also considered in this case, for a disease with a median age of 58 years (11–83) and a male-to-female ratio of 2.2, were one male neonate and six cases for whom neither sex nor age was indicated. Excluding gastrointestinal cases, the septic forms are associated with high morbidity, although the single case described involved a young and healthy subject. Risk factors for the pathogen or predisposing/pathological conditions for endocarditis did not emerge. The routes and the time of infection could not be determined, deepening the possibility of occupational exposure via the patient’s position as a boat worker. Poor sensitivity to third-generation cephalosporins has been reported in the literature: the absence of an antibiogram does not allow for a comparison, although resolution was achieved with ciprofloxacin. Conclusion: The rising global incidence of non-cholera Vibrio infections, driven by environmental changes, calls for urgent research into the factors behind their pathogenicity and infection routes. Diagnostic complexities have emerged together with clinical severity. Full article

Starry flounder (Platichthys stellatus) (weight 96.42 ± 19.17 g, length 20.65 ± 1.04 cm) were exposed to waterborne copper at 0, 0.5, 1, 3, 6, 12, 24, and 48 mg Cu²⁺/L for 96 h. The lethal concentration 50 (LC₅₀) of the P. stellatus exposed to waterborne copper was 15.644 mg Cu²⁺/L. Hemoglobin, hematocrit, and RBC count were significantly decreased by waterborne copper exposure. MCV (mean corpuscular volume) (µL) and MCHC (mean corpuscular hemoglobin concentration) (%) were also significantly decreased. The inorganic components, plasma calcium, and plasma magnesium were significantly increased. The organic components, such as plasma glucose, were significantly increased. In enzymatic components, the AST and ALT were also significantly increased by copper exposure. The results of this study indicate that exposure to copper may have effects on the survival rates and hematological parameters of the P. stellatus. Full article

Nanoplastics (NPs) pose a significant environmental threat due to their small sizes, widespread distribution, and bioavailability, enabling interactions with marine organisms from pelagic to benthic species. In this study, the effects of 10 days of exposure to waterborne poly(methyl)methacrylate (PMMA) NPs were evaluated in the crab Carcinus maenas by assessing behavioral and biochemical endpoints (in gills, hepatopancreas, muscle, and hemolymph). Behavioral assessments using an open field test revealed that exposure to PMMA NPs resulted in an increase in distance walked (from 73.662 ± 17.137 cm in control to 248.560 ± 25.462 cm in the highest PMMA NPs concentration) and in random movement patterns. Muscle acetylcholinesterase (AChE) activity decreased from 10.83 ± 0.73 to 6.75 ± 0.45 nmol/min/mg of protein with PMMA NPs concentration increase, which, combined with behavioral responses, suggests neurological incapacities. In the gills and hepatopancreas, defense and detoxification mechanisms were activated, with a significant increase in superoxide dismutase (SOD) activity (at 20 µg/L in gills and 80 µg/L in hepatopancreas) and glutathione S-transferases (GSTs) activity (all PMMA NPs concentrations in gills and 20 and 320 µg/L in hepatopancreas). Despite these activations, oxidative damage was observed, with a significant increase in protein carbonylation (PC) levels (20, 80, and 320 µg/L in gills and 5, 20, and 80 µg/L in hepatopancreas) and lipid peroxidation (LPO) (80 and 320 µg/L in gills and 80 µg/L in hepatopancreas). Effects on hemolymph followed a pattern similar to those reported for gills and hepatopancreas. An increase in SOD hemolymph activity was observed in organisms exposed to 5 and 80 µg/L, and GSTs activity increased in crabs exposed to 80 µg/L. Oxidative damage in hemolymph was only detected through LPO at 5 and 320 µg/L. Overall, this study showed that PMMA NPs induce biochemical alterations and damage in different tissues of C. maenas and affect its behavior with potential impacts at a population level. Full article

Conventional micro-surfacing materials often delaminate, crack, or peel. These defects shorten pavement life. High-performance polymer-modified mixtures are essential for rapid pavement maintenance. We added waterborne epoxy resin (WER) at different dosages to styrene–butadiene rubber (SBR) to create a composite-modified micro-surfacing mixture. A series of laboratory comparative tests were conducted to investigate the effect of WER content on the overall performance of the WER-SBR micro-surfacing mixture. In addition, the microstructure of the mixtures was observed to analyze the mechanism by which the composite-modified emulsified asphalt enhances material performance, and the optimal WER dosage was determined. The results showed that higher WER content improved abrasion and rutting resistance but gains plateaued above 6% WER. Below 9% WER, mixtures showed good water stability; at 3–6% WER, they also maintained skid and low-temperature crack resistance. Notably, when the WER content was approximately 6%, the WER-SBR micro-surfacing mixture showed significantly reduced abrasion damage after exposure to freeze–thaw cycles, moisture, and salt spray conditions. SEM images confirmed that 6% WER creates a uniform asphalt film over aggregates, boosting mixture performance. Therefore, we recommend 6% WER. This study has developed a WER-SBR composite-modified emulsified asphalt micro-surfacing product with excellent overall performance. It holds significant practical value for extending pavement service life and improving road service quality. Full article

Waterborne pathogens seriously threaten human life and can cause diarrhea, gastrointestinal disorders, and more serious systemic infections. These pathogens are usually caused by contaminated water sources that contain disease-causing microorganisms, such as bacteria, viruses, and parasites, which cause infection and disease when they enter the human body through drinking water or other means. Due to the wide range of transmission routes and the high potential risk of waterborne pathogens, there is an urgent need for an ultrasensitive, rapid, and specific pathogenic microorganism monitoring platform to meet the critical monitoring needs of some water bodies’ collection points daily monitoring needs. Microfluidics-based pathogen surveillance methods are an important stage towards automated detection through real-time and multi-targeted monitoring, thus enabling a comprehensive assessment of the risk of exposure to waterborne pathogens and even emerging microbial contaminants, and thus better protection of public health. Therefore, this paper reviews the latest research results on the isolation and detection of waterborne pathogens based on microfluidic methods. First, we introduce the traditional methods for isolation and detection of pathogens. Then, we compare some existing microfluidic pathogen isolation and detection methods and finally look forward to some future research directions and applications of microfluidic technology in waterborne pathogens monitoring. Full article

Lead (Pb) is a non-essential toxic metal that accumulates in aquatic environments, negatively impacting fish health. This study evaluated the acute toxicity of Pb in starry flounders (Platichthys stellatus). Fish (41 ± 8.1 g, 14 ± 0.9 cm) were exposed to Pb concentrations of 0, 10, 20, 40, 80, 160, 320, and 640 mg Pb²⁺/L for 96 h. The lethal concentration (96 h LC₅₀) was determined to be 227 mg Pb²⁺/L. Hematological analysis showed significant decreases in RBC counts, hemoglobin, and hematocrit, while MCH and MCHC increased at ≥160 mg Pb²⁺/L. Plasma calcium levels significantly decreased following Pb exposure, and AST activity was reduced. These findings suggest that acute waterborne Pb exposure adversely affects survival, hematological parameters, and plasma components in P. stellatus, providing insight into Pb toxicity in aquatic organisms. Full article

Corticosterone (CORT) is a key glucocorticoid hormone that regulates energy balance and physiological responses to environmental stressors, making it a valuable biomarker for assessing how organisms cope with changing conditions. Understanding how amphibians respond to chronic thermal stress is critical in the context of climate change and urbanization. We investigated the effects of a week-long exposure to elevated water temperatures on CORT release rates and growth in Gulf Coast toad (Incilius nebulifer) tadpoles, a species adapted to variable thermal environments. Using a non-invasive water-borne hormone method, we measured CORT at multiple time points (1 h, 2 h, 6 h, 24 h, 48 h, and 5 days) post-treatment to assess how CORT varied with time after exposure to elevated heat vs. the control temperature. We found a significant time-by-treatment response in tadpoles after a week of exposure to 32 °C versus 23 °C (control) temperatures. Both control and treatment individuals showed a marked decrease in CORT release rates 6 h post-return to room temperature, but by 24 h post-experiment, CORT release rates were higher in the tadpoles exposed to 32 °C. Heat-exposed tadpoles also showed significantly faster growth during and after treatment, but a lower survival to 12 days, indicating a potential trade-off between survival and accelerated growth. Overall, our study highlights a trade-off for populations of I. nebulifer when exposed to thermal stress and suggests that amphibian responses to chronic environmental stressors are shaped by adaptive physiological strategies, with implications for understanding and conserving amphibian populations in a rapidly changing world. Full article

Wood, a vital material for both modern and heritage objects, is particularly susceptible to degradation caused by water due to its hydrophilic nature and porous structure. Therefore, developing sustainable strategies to protect wood is of significant importance. This study aims to produce a highly hydrophobic coating for the protection of wood following a straightforward procedure and using materials that are compatible with wood. First, nano/sub-microlignin (NL) is isolated and produced from beech wood through a one-step tailored organosolv process. Next, NL is incorporated into Sivo 121, a water-borne and solvent-free silane system recommended by the manufacturer for protecting wood surfaces. Composite coatings containing various concentrations of NL and Sivo 121 are applied to chestnut (Castanea spp.) and oak (Quercus spp.). The impact of NL concentration on the contact angles of water drops (CAs) and colour changes (ΔE) of the treated wood specimens is investigated. The coating with 4% w/w NL demonstrates enhanced hydrophobicity (CA = 145°) and has a negligible effect on the colour of pristine oak (ΔE < 3). The wetting properties of coated oak are not affected after 100 tape peeling cycles. However, the coating exhibits poorer performance on chestnut, i.e., CA = 135°, which declines after 80 peeling cycles, and ΔE > 5. The drop pH does not have any noticeable effect on CA. The latter remains stable even after prolonged exposure of coated oak and chestnut samples to artificial UV radiation and outdoor environmental conditions. Finally, the composite coating offers good and comparable protection for both wood species in the biological durability soil burial test Full article

Cadmium (Cd) is a highly toxic substance in the aquatic ecosystem, which can represent a high risk to fish. Fish are exposed to heavy metals through waterborne and dietary pathways, some of which are absorbed by the body and can accumulate in specific tissues without being eliminated. The accumulation varies depending on several factors such as dose, exposure route, exposure time, metal types, and biological status of the fish, and environmental parameters such as DO, salinity, pH, and metal speciation. As Cd speciation occurs in the water, the amount accumulated in the fish can vary, and consuming Cd-accumulated fish can pose a risk to human health. Cd introduced into the body of fish can directly affect blood properties through the circulatory system. Cd introduced into the circulatory system of fish can reach all tissues through the blood flow, and the accumulation of specific tissues is different depending on the blood flow by the energy and oxygen demand of each tissue. Therefore, this review aimed to determine the toxic effects of Cd exposure in fish and identify indicators to assess the extent of Cd bioaccumulation toxicity in fish induced by Cd exposure. Full article

For the removal of waterborne pathogens in remote areas and disaster emergency situations, point-source water treatment methods are more suitable. Photothermal sterilization is ideal for point-of-use (POU) systems, as it effectively eliminates pathogens without secondary pollution or bacterial resistance issues. By combining photothermal with membrane treatment, these membranes rapidly heat up under near-infrared (NIR) light, enabling both bacterial retention and sterilization. However, the decrease in membrane flux due to pore clogging during water treatment can significantly impact membrane efficiency. And adjusting the membrane pore size can significantly enhance flux recovery during cleaning, thereby restoring membrane efficiency. By synthesis multifunctional membranes that combine bacteria retention, sterilization, and flux recovery, it can meet the requirements of point-source water treatment: compact size, high efficiency, good safety, and easy maintenance. In this study, we developed an intelligent thermally responsive membrane (NIPAN@CNTs/PAN) by incorporating carbon nanotubes (CNTs) and forming a copolymer of N-isopropylacrylamide and polyacrylonitrile (NIPAN) coating into polyacrylonitrile membranes, offering dual functions of photothermal sterilization and self-cleaning. With 3% CNTs, the membrane achieves 100% sterilization within 6 min of NIR exposure, while the NIPAN layer’s added roughness boosts photothermal efficiency, achieving 100% sterilization within 4 min. Rinsing at 50 °C improved flux recovery from 50% to 87% and reduced irreversible fouling from 49.7% to 12.9%, demonstrating stable performance over multiple cycles and highlighting its potential for long-term use in practical POU applications. Full article

Predicting public health risk associated with exposure to and recreational use of surface waters is often challenging due to substantial variability in concentrations of pathogenic bacteria, even among seemingly similar streams. In this study, we document significant differences in the surface water concentrations of the common bacteria indicators Escherichia coli and fecal coliform between two major stream types—blackwater and redwater streams (p < 0.001). We propose and present evidence that these findings result from natural biogeochemical variation between physiographic regions (p < 0.001). These findings suggest that physiographic stream type may influence the degree of exposure to waterborne pathogens and risk of waterborne disease. Future research is needed to assess whether the inclusion of stream type in risk assessments can improve public health modeling and mapping. Full article

Lead (Pb) is a well-known neurotoxin with established adverse effects on the neurological functions of children and younger adults, including motor, learning, and memory abilities. However, its potential impact on older adults has received less attention. Using the zebrafish model, our study aims to characterize the dose–response relationship between environmentally relevant Pb exposure levels and their effects on changes in behavior and transcriptomics during the geriatric periods. We exposed two-year-old zebrafish to waterborne lead acetate (1, 10, 100, 1000, or 10,000 µg/L) or a vehicle (DMSO) for 5 days. While lower concentrations (1–100 µg/L) reflect environmentally relevant Pb levels, higher concentrations (1000–10,000 µg/L) were included to assess acute toxicity under extreme exposure scenarios. We conducted adult behavior assessment to evaluate the locomotor activity following exposure. The same individual fish were subsequently sacrificed for brain dissection after a day of recovery in the aquatic system. RNA extraction and sequencing were then performed to evaluate the Pb-induced transcriptomic changes. Higher (1000–10,000 ug/L) Pb levels induced hyperactive locomotor patterns in aged zebrafish, while lower (10–100 ug/L) Pb levels resulted in the lowest locomotor activity compared to the control group. Exposure to 100 µg/L led to the highest number of differentially expressed genes (DEGs), while 10,000 µg/L induced larger fold changes in both directions. The neurological pathways impacted by Pb exposure include functions related to neurotransmission, such as cytoskeletal regulation and synaptogenesis, and oxidative stress response, such as mitochondrial dysfunction and downregulation of heat shock protein genes. These findings emphasize a U-shape dose–response relationship with Pb concentrations in locomotor activity and transcriptomic changes in the aging brain. Full article

In saline soil areas, the concrete piers of concrete bridges experience long-term corrosion, mainly caused by chloride salts due to alternating temperature changes. Waterborne concrete coatings are prone to failure in this aggressive salt environment. Implementing coating protection measures can improve the durability of concrete and enhance the service life of bridges. However, the effectiveness and longevity of coatings need further research. In this paper, three types of waterborne concrete anti-corrosion coatings were applied to analyze the macro and micro surface morphology under wet–dry cycles and long-term immersion conditions. Various indicators such as glossiness, color difference, and adhesion of the coatings were tested during different cyclic periods. The chloride ion distribution characteristics of the buried concrete coatings in saline soil, the macro morphology analysis of chloride ion distribution regions, and the micro morphology changes of the coatings under different corrosion times were also investigated. The results showed that waterborne epoxy coatings (ES), waterborne fluorocarbon coatings (FS), and waterborne acrylic coatings (AS) all gradually failed under long-term salt exposure, with increasing coating porosity, loss of internal fillers, and delamination. The chloride ion content inside the concrete decreased with increasing depth at the same corrosion time, while the chloride ion content at the same depth increased with time. The chloride ion distribution boundary in the cross-section of concrete with coating protection was not significant, while the chloride ion distribution boundary in the cross-section of untreated concrete gradually contracted towards the concrete core with increasing corrosion time. During the corrosion process in saline soil, the coatings underwent three stages: adherence of small saline soil particles, continuous increase in adhered material area, and multiple layers of uneven coverage by saline soil. The failure process of the coatings still required erosive ions to infiltrate the surface through micropores. The predicted lifespans of FS, ES, and AS coatings, obtained through weighted methods, were 2.45 years, 2.48 years, and 2.74 years, respectively, which were close to the actual lifespans observed in salt environments. The developed formulas effectively reflect the corrosion patterns of different resin-based coatings under salt exposure, providing a basis for accurately assessing the corrosion behavior and protective effectiveness of concrete under actual environmental factors. Full article