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Journal of Environmental and Public... 2019There is scarcity of information about the quality and safety of drinking water in Africa. Without such vital information, sustainable development goal number 6 which...
BACKGROUND
There is scarcity of information about the quality and safety of drinking water in Africa. Without such vital information, sustainable development goal number 6 which promotes availability and sustainable management of water and sanitation remains elusive especially in developing countries. The study aimed at determining concentrations of inorganic compounds, estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), incremental lifetime cancer risk (ILCR), and identify safe drinking water source sources in Southwestern Uganda.
METHODS
This was an observational study in which 40 drinking water samples were collected from georeferenced boreholes, springs, open wells, bottled, and taps within Bushenyi district of Southwestern Uganda. Water samples were analyzed for copper (Cu), iron (Fe), zinc (Zn), lead (Pb), cadmium (Cd), and chromium (Cr) levels using atomic absorption spectrometry (AAS). Water safety measures (EDI, HI, and ILCR) were established for each water source and compared with local and international water permissible standards for each analyte. A spatial map was drawn using qGIS®, and analysis of quantitative data was done using MS Excel 2013 at 95% significance.
RESULTS
Heavy metals were present in the following order: 11.276 ppm > 4.4623 ppm > 0.81 ppm > 0.612 ppm > 0.161 ppm for Fe, Zn, Pb, Cu, and Cd, respectively, while Cr was not detected. Fe was the primary water heavy metal in the order of open well > borehole > tap > spring > bottled water. This was followed by Zn levels in the order of tap > bottled > spring > borehole > open well. All compounds were within international water safety standards except Pb. Hence, there is need for the government of Uganda to establish water filtration systems, particularly for Pb to improve the quality of water for the general public. The EDI was similar ( > 0.05) for water consumed from spring, bottled, and tap sources for Fe and Zn levels. Similarly, no differences were found in the EDI for children and adults ( > 0.05). Furthermore, the HI showed an absence of noncarcinogenic risk associated (HI < 1), although the ILCR was higher in adults than children ( < 0.05) due to high Cd concentrations.
CONCLUSION
The current identified Fe is a major heavy metal in drinking water of Uganda, and boreholes were the major safest sources of drinking water identified in this study.
Topics: Dietary Exposure; Drinking Water; Humans; Metals, Heavy; Risk Assessment; Uganda; Water Pollutants, Chemical; Water Quality; Water Supply
PubMed: 31019536
DOI: 10.1155/2019/7813962 -
Microbiome Mar 2020Limiting microbial growth during drinking water distribution is achieved either by maintaining a disinfectant residual or through nutrient limitation without using a...
Limiting microbial growth during drinking water distribution is achieved either by maintaining a disinfectant residual or through nutrient limitation without using a disinfectant. The impact of these contrasting approaches on the drinking water microbiome is not systematically understood. We use genome-resolved metagenomics to compare the structure, metabolic traits, and population genomes of drinking water microbiome samples from bulk drinking water across multiple full-scale disinfected and non-disinfected drinking water systems. Microbial communities cluster at the structural- and functional potential-level based on the presence/absence of a disinfectant residual. Disinfectant residual alone explained 17 and 6.5% of the variance in structure and functional potential of the drinking water microbiome, respectively, despite including multiple drinking water systems with variable source waters and source water communities and treatment strategies. The drinking water microbiome is structurally and functionally less diverse and variable across disinfected compared to non-disinfected systems. While bacteria were the most abundant domain, archaea and eukaryota were more abundant in non-disinfected and disinfected systems, respectively. Community-level differences in functional potential were driven by enrichment of genes associated with carbon and nitrogen fixation in non-disinfected systems and γ-aminobutyrate metabolism in disinfected systems likely associated with the recycling of amino acids. Genome-level analyses for a subset of phylogenetically-related microorganisms suggests that disinfection selects for microorganisms capable of using fatty acids, presumably from microbial decay products, via the glyoxylate cycle. Overall, we find that disinfection exhibits systematic selective pressures on the drinking water microbiome and may select for microorganisms able to utilize microbial decay products originating from disinfection-inactivated microorganisms. Video abstract.
Topics: Archaea; Bacteria; Disinfectants; Disinfection; Drinking Water; Eukaryota; Metagenomics; Microbiota; Water Purification
PubMed: 32197656
DOI: 10.1186/s40168-020-00813-0 -
Eastern Mediterranean Health Journal =... Nov 2016Drinking water at Shatila Palestinian Refugee Camp in Beirut, Lebanon is of poor quality and unpredictably intermittent quantity. We aimed to characterize drinking water...
Drinking water at Shatila Palestinian Refugee Camp in Beirut, Lebanon is of poor quality and unpredictably intermittent quantity. We aimed to characterize drinking water sources and contamination at Shatila and determine how drinking water can be managed to reduce community health burdens. We interviewed the Popular Committee, well owners, water vendors, water shopkeepers and preschool administrators about drinking water sources, treatment methods and the population served. Water samples from the sources and intermediaries were analysed for thermotolerant faecal coliforms (FCs), Giardia lamblia, Cryptosporidium parvum and microsporidia, using immunofluorescent antibody detection for G. lamblia and C. parvum, and chromotrope-2 stain for microsporidia. All drinking water sources were contaminated with FCs and parasites. FC counts (cfu/mL) were as follows: wells (35-300), water vendors (2-178), shops (30-300) and preschools (230-300). Responsible factors identified included: unskilled operators; improper maintenance of wells and equipment; lack of proper water storage and handling; and misperception of water quality. These factors must be addressed to improve water quality at Shatila and other refugee camps.
Topics: Drinking Water; Interviews as Topic; Lebanon; Refugees; Water Pollution; Water Purification; Water Wells
PubMed: 27834438
DOI: 10.26719/2016.22.8.568 -
Journal of Water and Health Dec 2014Anatoxin-a (ANTX-a) is a potent alkaloid neurotoxin, produced by several species of cyanobacteria and detected throughout the world. The presence of cyanotoxins,... (Review)
Review
Anatoxin-a (ANTX-a) is a potent alkaloid neurotoxin, produced by several species of cyanobacteria and detected throughout the world. The presence of cyanotoxins, including ANTX-a, in drinking water sources is a potential risk to public health. This article presents a thorough examination of the cumulative body of research on the use of drinking water treatment technologies for extracellular ANTX-a removal, focusing on providing an analysis of the specific operating parameters required for effective treatment and on compiling a series of best-practice recommendations for owners and operators of systems impacted by this cyanotoxin. Of the oxidants used in drinking water treatment, chlorine-based processes (chlorine, chloramines and chlorine dioxide) have been shown to be ineffective for ANTX-a treatment, while ozone, advanced oxidation processes and permanganate can be successful. High-pressure membrane filtration (nanofiltration and reverse osmosis) is likely effective, while adsorption and biofiltration may be effective but further investigation into the implementation of these processes is necessary. Given the lack of full-scale verification, a multiple-barrier approach is recommended, employing a combination of chemical and non-chemical processes.
Topics: Cyanobacteria Toxins; Drinking Water; Tropanes; Water Pollutants, Chemical; Water Purification
PubMed: 25473970
DOI: 10.2166/wh.2014.018 -
Journal of Water and Health Aug 2016Quantitative microbial risk assessment (QMRA), the assessment of microbial risks when model inputs and estimated health impacts are explicitly quantified, is a valuable... (Review)
Review
Quantitative microbial risk assessment (QMRA), the assessment of microbial risks when model inputs and estimated health impacts are explicitly quantified, is a valuable tool to support water safety plans (WSP). In this paper, research studies undertaken on the application of QMRA in drinking water systems were reviewed, highlighting their relevance for WSP. The important elements for practical implementation include: the data requirements to achieve sufficient certainty to support decision-making; level of expertise necessary to undertake the required analysis; and the accessibility of tools to support wider implementation, hence these aspects were the focus of the review. Recommendations to support the continued and growing application of QMRA to support risk management in the water sector are provided.
Topics: Drinking Water; Models, Theoretical; Risk Assessment; Safety Management; Water Microbiology; Water Purification; Water Supply
PubMed: 27441853
DOI: 10.2166/wh.2016.262 -
Preventing Chronic Disease Dec 2020Recent legislation requires public and charter schools in California to test drinking water for lead. Our objective was to describe 1) results from this testing program...
INTRODUCTION
Recent legislation requires public and charter schools in California to test drinking water for lead. Our objective was to describe 1) results from this testing program in the context of other available water safety data and 2) factors related to schools and water utilities associated with access to safe drinking water in schools.
METHODS
Our study focused on a random sample of 240 California public and charter schools. We used multivariable logistic regression, accounting for clustering of tested water sources in schools, to examine school-level factors associated with failure to meet lead-testing deadlines and any history of water utility noncompliance.
RESULTS
Of the 240 schools, the majority (n = 174) tested drinking water for lead. Of the schools tested, 3% (n = 6) had at least 1 sample that exceeded 15 parts per billion (ppb) (California action level) and 16% (n = 28) exceeded 5 ppb (bottled water standard). Suburban schools had lower odds of being served by noncompliant water systems (OR = 0.17; CI, 0.05-0.64; P = .009) than city schools. Compared with city schools, rural schools had the highest odds of not participating in the water testing program for lead (OR = 3.43; CI, 1.46-8.05; P = .005). Hallways and common spaces and food services areas were the most frequent school locations tested; one-third of all locations sampled could not be identified.
CONCLUSION
In our study, geography influenced access to safe drinking water in schools, including both water utility safety standards and school lead-testing practices. Considerations for improving the implementation of state lead-testing programs include establishing priority locations for sampling, precisely labeling samples, and developing well-defined testing and reporting protocols.
Topics: California; Child; Cross-Sectional Studies; Drinking Water; Female; Health Policy; Humans; Lead Poisoning; Male; Schools; Students
PubMed: 33416472
DOI: 10.5888/pcd17.200366 -
Accounts of Chemical Research May 2019Wildfires are a natural part of most forest ecosystems, but due to changing climatic and environmental conditions, they have become larger, more severe, and potentially...
Wildfires are a natural part of most forest ecosystems, but due to changing climatic and environmental conditions, they have become larger, more severe, and potentially more damaging. Forested watersheds vulnerable to wildfire serve as drinking water supplies for many urban and rural communities. The highly variable nature of wildfire behavior combined with spatially complex patterns in vegetation, landscape, and hydrologic factors create uncertainty surrounding the postfire effects on water supplies. Wildfires often cause dramatic changes in forest vegetation structure and soil conditions, and alter the watershed processes that control streamflow, soil erosion, nutrient export, and downstream water chemistry. The authors' work centers on field and laboratory studies to advance knowledge of postfire changes in soil and water chemical composition that influence drinking water treatment. High intensity postfire rainstorms typically increase runoff that erodes ash and soil from burned landscapes and dramatically elevates turbidity, nutrient, and dissolved organic carbon (DOC) levels in surface waters, which can cause short-term challenges for water providers. There is also growing evidence that water quality impacts can persist after high severity fires due to slow vegetative recovery, and nitrogen and DOC have remained elevated for 15 years following high severity fire. Low-moderate temperatures during wildfire may also influence water quality. Research by the authors showed that the solubility of organic matter, and C and N released from soils increased following soil heating at temperatures ≤ 350 °C. Further, the water extracted organic matter from soils heated at 225-350 °C included higher proportions of condensed aromatic structures, such as black carbon and black nitrogen. Short-term postfire water quality degradation following high intensity rainstorms can force water treatment plants to shut down or can significantly challenge treatment process performance. Extreme turbidity and high DOC in poststorm water, coupled with compositional organic matter changes, reduced the coagulation efficiency of postfire water supplies. Field and lab-based studies documented the formation of small, aromatic soluble compounds during wildfire that contribute to inefficient DOC removal from postfire stormwater. Due to increased postfire DOC concentrations, and poor treatability of poststorm runoff, toxic disinfection byproduct (DBP) formation increased during water treatment. Exceedance of drinking water standards for the carbonaceous DBPs, trihalomethanes and haloacetic acids, may present a critical management concern for water providers following wildfires. Further, postfire formation of nitrogen compounds and increased nitrogenous DBP precursors for haloacetonitriles and chloropicrin were discovered. N-DBPs pose a public health concern due to their toxicity, and water providers should be aware of potential increases in N-DBP formation following fire. Evidence from the authors' studies demonstrates that even partially burned watersheds and wildfires burning at moderate temperature can have significant, lasting effects on C and N exports, source water quality, drinking water treatability, and DBP formation. Both short- and long-term postfire water quality impacts can create challenges for drinking water providers as they confront variability in supply and treatability. Communities, forest managers, and potable water providers will need to adapt to more frequent, destructive wildfires and anticipate greater variability in water quality.
Topics: Carbon; Drinking Water; Forests; Fresh Water; Nitrogen; Water Pollutants, Chemical; Water Purification; Water Quality; Wildfires
PubMed: 31059225
DOI: 10.1021/acs.accounts.8b00670 -
International Journal of Geriatric... Mar 2023Lithium, a mood stabilizer, is known to exhibit neuroprotective effects in animal models and may have anti-dementia effects.
BACKGROUND
Lithium, a mood stabilizer, is known to exhibit neuroprotective effects in animal models and may have anti-dementia effects.
AIMS
We used data from Scottish Mental Survey 1932, a population-based cohort study, to investigate the association between lithium in drinking water and dementia rate in humans.
METHOD
Lithium levels in drinking water from 285 sampling sites across Scotland dating from 2014 were obtained from the sole public water provider (Scottish Water). Dementia and non dementia cases were identified from cohort data by electronic health records until 2012, and linked to postcode.
RESULTS
The mean lithium level at all sampling sites was 1.45 μg/L (SD 1.83, range 0.5-18.2) and was 1.26 (SD 0.63, range 0.55-9.19) for sites matched to participant data. Of 37,597 study members, 3605 developed dementia until June 2012. Lithium levels were positively associated with the risk of dementia in women (highest in second quartile, HR 1.17, 95%CI 1.04-1.32), but there was no relationship in men (highest in second quartile, HR 0.95, 95% CI 0.81-1.12). The pattern of association was explored further by decile, and in females there was an association between lithium level and increased dementia risk compared to the lowest decile (0.55-0.68 μg/L) in all deciles except the highest, corresponding with lithium levels 0.68-2.1 μg/L.
CONCLUSIONS
Lithium levels in drinking water are very low across Scotland which limited detection of potential effect. Our results do not support an association between extremely low levels of lithium and later dementia risk. We found a trend to increased risk in females at lithium levels below but not above 2.1 μg/L.
Topics: Male; Humans; Female; Lithium; Cohort Studies; Drinking Water; Surveys and Questionnaires
PubMed: 36747488
DOI: 10.1002/gps.5890 -
Neurotoxicology and Teratology 2023Fluoride (F) exposure in drinking water may lead to reduced cognitive function among children; however, findings largely remain inconclusive. In this pilot study, we...
Fluoride (F) exposure in drinking water may lead to reduced cognitive function among children; however, findings largely remain inconclusive. In this pilot study, we examined associations between a range of chronic F exposures (low to high: 0.4 to 15.5 mg/L) in drinking water and cognition in school-aged children (5-14 years, n = 74) in rural Ethiopia. Fluoride exposure was determined from samples of community-based drinking water wells and urine. Cognitive performance was measured using: 1) assessments of ability to draw familiar objects (donkey, house, and person), and 2) a validated Cambridge Neuropsychological Test Automated Battery's (CANTAB) Paired Associate Learning (PAL), which examines memory and new learning and is closely associated with hippocampus function of the brain. Associations between F and cognitive outcomes were evaluated using regression analysis, adjusting for demographic, health status, and other covariates. The median (range) of water and urine F levels was 7.6 (0.4-15.5 mg/L) and 6.3 (0.5-15.7 mg/L), respectively; these measures were strongly correlated (r = 0.74), indicating that water is the primary source of F exposure. Fluoride in drinking water was negatively associated with cognitive function, measured by both drawing and CANTAB test performance. Inverse relationships were also found between F and drawing objects task scores, after adjusting for covariates (p < 0.05). Further analysis using CANTAB PAL tasks in the children confirmed that F level in drinking water was positively associated with the number of errors made by children (p < 0.01), also after adjusting for covariates (p < 0.05). This association between water F and total errors made became markedly stronger as PAL task difficulty increased. Fluoride exposure was also inversely associated with other PAL tasksthe number of patterns reached, first attempt memory score and mean errors to success. These findings provide supportive evidence that high F exposures may be associated with cognitive deficits in children. Additional well-designed studies are critically needed to establish the neurotoxicity of F in children and adults exposed to both low levels known to protect dental caries, as well as excess F levels in drinking water.
Topics: Humans; Child; Fluorides; Drinking Water; Pilot Projects; Dental Caries; Cognition
PubMed: 37690675
DOI: 10.1016/j.ntt.2023.107293 -
Acta Medica Portuguesa Feb 2019
Topics: Drinking Water; Lithium; Portugal; Suicide
PubMed: 30896404
DOI: 10.20344/amp.11945