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1.
Nature ; 619(7969): 317-322, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37438590

RESUMEN

Plastic debris is thought to be widespread in freshwater ecosystems globally1. However, a lack of comprehensive and comparable data makes rigorous assessment of its distribution challenging2,3. Here we present a standardized cross-national survey that assesses the abundance and type of plastic debris (>250 µm) in freshwater ecosystems. We sample surface waters of 38 lakes and reservoirs, distributed across gradients of geographical position and limnological attributes, with the aim to identify factors associated with an increased observation of plastics. We find plastic debris in all studied lakes and reservoirs, suggesting that these ecosystems play a key role in the plastic-pollution cycle. Our results indicate that two types of lakes are particularly vulnerable to plastic contamination: lakes and reservoirs in densely populated and urbanized areas and large lakes and reservoirs with elevated deposition areas, long water-retention times and high levels of anthropogenic influence. Plastic concentrations vary widely among lakes; in the most polluted, concentrations reach or even exceed those reported in the subtropical oceanic gyres, marine areas collecting large amounts of debris4. Our findings highlight the importance of including lakes and reservoirs when addressing plastic pollution, in the context of pollution management and for the continued provision of lake ecosystem services.


Asunto(s)
Lagos , Plásticos , Contaminación del Agua , Abastecimiento de Agua , Ecosistema , Lagos/química , Plásticos/análisis , Plásticos/clasificación , Contaminación del Agua/análisis , Contaminación del Agua/estadística & datos numéricos , Encuestas y Cuestionarios , Urbanización , Actividades Humanas
2.
Arch Microbiol ; 206(7): 295, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856934

RESUMEN

Microbial community biofilm exists in the household drinking water system and would pose threat to water quality. This paper explored biofilm formation and chlorination resistance of ten dual-species biofilms in three typical household pipes (stainless steel (SS), polypropylene random (PPR), and copper), and investigated the role of interspecific interaction. Biofilm biomass was lowest in copper pipes and highest in PPR pipes. A synergistic or neutralistic relationship between bacteria was evident in most biofilms formed in SS pipes, whereas four groups displayed a competitive relationship in biofilms formed in copper pipe. Chlorine resistance of biofilms was better in SS pipes and worse in copper pipes. It may be helped by interspecific relationships, but was more dependent on bacteria and resistance mechanisms such as more stable extracellular polymeric substance. The corrosion sites may also protect bacteria from chlorination. The findings provide useful insights for microbial control strategies in household drinking water systems.


Asunto(s)
Bacterias , Biopelículas , Cloro , Agua Potable , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Cloro/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificación , Agua Potable/microbiología , Cobre/farmacología , Microbiología del Agua , Acero Inoxidable , Polipropilenos , Abastecimiento de Agua , Halogenación , Corrosión , Desinfectantes/farmacología
3.
Biofouling ; 40(3-4): 262-279, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38695072

RESUMEN

In newly commissioned drinking-water polyethylene (PE) pipes, biofilm develops on the inner pipe surface. The microbial community composition from colonization to the establishment of mature biofilms is less known, including the effect on the distributed water quality. Biofilm development was followed through 1.5 years in PE-pipe side streams at two locations of a full-scale, non-chlorinated drinking-water distribution system (leaving a waterworks versus 5-6 km from a waterworks) along with inlet and outlet water quality. Mature biofilms were established after ∼8-9 months, dominated by Proteobacteria, Actinobacteria and Saccharibacteria (61-93% relative abundance), with a higher diversity (OTUs/Shannon Index/16S rRNA gene amplicon sequencing) in pipes in the far end of the distribution system. Comamonadaceae, and specifically Aquabacterium (>30% of reads), dominated young (∼1.5-month-old) biofilms. Young biofilms were linked to increased microbiological counts in drinking water (HPC/ATP/qPCR), while the establishment of mature biofilms led to a drop in HPC and benefited the water quality, highlighting the importance of optimizing commissioning procedures for rapidly achieving mature and stable biofilms.


Asunto(s)
Biopelículas , Agua Potable , Polietileno , Abastecimiento de Agua , Biopelículas/crecimiento & desarrollo , Agua Potable/microbiología , Microbiología del Agua , Dinamarca , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Calidad del Agua , ARN Ribosómico 16S/genética
4.
J Environ Manage ; 351: 119614, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38043309

RESUMEN

This comprehensive review delves into the forefront of wastewater treatment technology, with a specific focus on the revolutionary concept of Zero Liquid Discharge (ZLD). (ZLD), underpinned by a sustainable ethos, aspires to accomplish total water reclamation, constituting a pivotal response to pressing environmental issues. The paper furnishes a historical panorama of (ZLD), elucidating its motivating factors and inherent merits. It navigates a spectrum of (ZLD) technologies encompassing thermal methodologies, (ZLD) synergized with Reverse Osmosis (RO), High-Efficiency Reverse Osmosis (HERO), Membrane Distillation (MD), Forward Osmosis (FO), and Electrodialysis Reversal (EDR). Moreover, the study casts a global purview over the deployment status of (ZLD) systems in pursuit of resource recovery, accentuating nations such as the United States, China, India, assorted European Union members, Canada, and Egypt. Meticulous case studies take center stage, underscoring intricate scenarios involving heavily contaminated effluents from challenging sectors including tanneries, textile mills, petroleum refineries, and paper mills. The report culminates by distilling sagacious observations and recommendations, emanating from a collaborative brainstorming endeavor. This compendium embarks on an enlightening journey through the evolution of wastewater treatment, (ZLD)'s ascendancy, and its transformative potential in recalibrating water management paradigms while harmonizing industrial progress with environmental stewardship.


Asunto(s)
Resiliencia Psicológica , Purificación del Agua , Aguas Residuales , Agua , Membranas Artificiales , Ósmosis , Tecnología , Abastecimiento de Agua
5.
Int J Environ Health Res ; 34(1): 625-638, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36617354

RESUMEN

Water use of domestic activities was quantified by interviewing 217 people in a peri-urban community near Bandung, Indonesia. Resulting in data on domestic water demand and data needed for exposure modelling of domestic activities: drinking, cooking, brushing teeth, swimming, bathing, laundry, dishwashing, religious cleansing, washing hands and cleaning food. Average total domestic water usage was 117 l/person/day, topping the WHO guidelines for basic needs (50-100 l/person/day). This water use level is comparable with higher income countries for the same set of activities but 100% higher than water use in an Indonesian traditional rural community. The final dataset provides insight in quantity of water used for domestic activities, as well as the use-frequency, duration and water sources used. These data are scarce for Indonesia and other low-middle income countries but necessary for water demand studies and estimating risks through exposure to pathogens and emerging contaminants in human exposure modelling.


Asunto(s)
Abastecimiento de Agua , Agua , Humanos , Indonesia , Población Rural
6.
J Clin Pediatr Dent ; 48(1): 111-119, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38239163

RESUMEN

Despite efforts to promote breastfeeding, many babies aged <6 months receive only baby formula reconstituted with bottled water. The intake of high levels of fluoride during amelogenesis has been associated with hypomineralization of the tooth enamel, with aesthetic and mechanical repercussions. The objective of this study was to determine the potential risk of dental fluorosis associated with baby formulas marketed in Spain. We measured 26 baby formulas frequently consumed in Spain; 17 brands for babies aged <6 months, 5 for those aged >6 months, and 4 ready-to-use brands. They were prepared with 4 types of water: distilled water and three brands of bottled water with different levels of fluoride. The fluoride concentration (mg/L or ppm F) was measured with an ion-specific electrode coupled to an ion analyzer. Each sample was prepared according to the manufacturer's instructions and analyzed in triplicate. A descriptive analysis was carried out. The minimum fluoride level found was 0.04 mg/L and the maximum was 1.02 mg/L. Considering the daily intake of these formulas, none exceeded the clinically-acceptable daily dose limit risk for fluorosis (0.07 mg F/day/kg body weight) when mixed with bottled water with a low level of fluoride (0.1 mg/L). However, when the same brands of formula were reconstituted with bottled water with a higher fluoride content (0.99 mg/L), they all exceeded the daily dose limit for the risk of fluorosis. As the potential risk of dental fluorosis associated with the formulas tested depends exclusively on the fluoride concentration of the waters used for reconstitution, formula packaging should contain a warning.


Asunto(s)
Agua Potable , Fluorosis Dental , Lactante , Humanos , Fórmulas Infantiles/efectos adversos , Fluoruros , Fluorosis Dental/etiología , Agua Potable/análisis , España , Abastecimiento de Agua
7.
Environ Sci Technol ; 57(16): 6387-6402, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37052478

RESUMEN

Water-soluble synthetic polymers (WSPs) are distinct from insoluble plastic particles, which are both critical components of synthetic polymers. In the history of human-made macromolecules, WSPs have consistently portrayed a crucial role and served as the ingredients of a variety of products (e.g., flocculants, thickeners, solubilizers, surfactants, etc.) commonly used in human society. However, the environmental exposures and risks of WSPs with different functions remain poorly understood. This paper provides a critical review of the usage, environmental fate, environmental persistence, and biological consequences of multiple types of WSPs in commercial and industrial production. Investigations have identified a wide market of applications and potential environmental threats of various types of WSPs, but we still lack the suitable assessment tools. The effects of physicochemical properties and environmental factors on the environmental distribution as well as the transport and transformation of WSPs are further summarized. Evidence regarding the degradation of WSPs, including mechanical, thermal, hydrolytic, photoinduced, and biological degradation is summarized, and their environmental persistence is discussed. The toxicity data show that some WSPs can cause adverse effects on aquatic species and microbial communities through intrinsic toxicity and physical hazards. This review may serve as a guide for environmental risk assessment to help develop a sustainable path for WSP management.


Asunto(s)
Purificación del Agua , Agua , Humanos , Abastecimiento de Agua , Polímeros , Plásticos
8.
Sensors (Basel) ; 23(13)2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37448054

RESUMEN

Water Loss (WL) is a global issue. In Italy, for instance, WL reached 36.2% of the total fresh water conveyed in 2020. The maintenance of a water supply system is a strategic task that requires a huge amount of investment every year. In this work, we focused on the use of Distributed Fiber Optic Sensors (DFOS) based on Stimulated Brillouin Scattering (SBS) technology for monitoring water pipeline networks. We worked on High-Density Polyethylene (HDPE) pipes, today the most widely used for creating water pipelines. By winding and fixing the optic fiber cable on the pipe's external surface, we verified the ability to detect strain related to pressure anomalies along a pipeline, e.g., those caused by water leakage. We performed two experimental phases. In the first one, we assessed the sensibility of sensor layout on an HDPE pipeline solicited with static pressure. We investigated the viscoelastic rheology of the material by calibrating and validating the parameters of a Burger model, in which Maxwell and Kelvin-Voigt models are connected in series. In the second experimental phase, instead, we focused on the detection of the pressure anomaly produced by leakage in a pipeline circuit set up with running water moved by a pump. The theoretical and experimental studies performed returned overall positive feedback on the use of DFOS for the monitoring of HDPE water pipelines. Future developments will be focused on more detailed studies of this monitoring solution and on the industrial production of "natively smart" HDPE pipes in which DFOS cables are integrated into the pipeline surface during the extrusion process.


Asunto(s)
Polietileno , Abastecimiento de Agua , Tecnología de Fibra Óptica , Agua , Agua Dulce
9.
J Environ Manage ; 345: 118779, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37586171

RESUMEN

The role of the water distribution system (WDS) requires that it supply water of sufficient quality to households. Unregulated leaching of micro and nanoplastics from plastic pipes of the distribution system is therefore a cause for concern, particularly with the rise in research associating these plastic particles to adverse health impacts in living organisms. Within this study, four parameters (pH, free chlorine concentration, pipe material, and time) were varied in a pipe loop network to observe their effect on microplastic (MP) and nanoplastic (NP) leaching into the simulated distribution network. Results indicated an abundance of MPs/NPs in different shapes and sizes throughout the samples. Graphical trends illustrated that basic pH values contributed to a higher number of particles. Statistical analysis via analysis of variance (ANOVA) confirmed this observation and further showed interaction of chlorine dose and pH concentration (p-value = 0.000), and chlorine dose and pipe material (p-value = 0.038) was also significant to leaching. Numerically, polyethylene (PE) particles were the most abundant with a total of 15194 particles, followed by 12920 polypropylene random copolymer (PPR) particles and 12317 polyvinyl chloride (PVC) particles. It was also noticed that the number of particles decreased with time.© 2023 Elsevier Inc. All rights reserved.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Agua/química , Abastecimiento de Agua , Microplásticos , Cloro/análisis , Cloro/química , Plásticos/química , Cloruros , Contaminantes Químicos del Agua/análisis
10.
Environ Monit Assess ; 195(2): 325, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36692796

RESUMEN

Fluorine is a naturally occurring element found in soil, water, food materials, and natural minerals such as fluorapatite, sellaite, and cryolite and exists as fluoride compounds with other elements because of high reactivity. The exposure of fluoride to the environment and human beings are industrial factors, food, water, and geogenic factors that impact the health of millions of human beings worldwide. Overexposure to fluoride exceeding the permissible limit (1.5 mg/l as per WHO) causes several diseases in human beings, such as teeth mottling, thyroid inflammation, dental fluorosis, skeletal fluorosis, lesions in the kidney, and other organs. To overcome the deleterious impact of fluoride, its detection at an early stage is very much required. Therefore, feeling the importance of the same, immense efforts have been made to the selective and sensitive determination of fluoride in water by numerous researchers. This review paper summarizes the various conventional methods such as spectroscopic, ion chromatography, ICP-OES, and gas chromatography-mass spectrometry, their advantages, and drawbacks leading to the development of advanced ready-to-use detection strategies such as stamartphones for on-the-spot fluoride detection. This review paper also discusses future directions, which will assist scientists in achieving a new benchmark in developing a reliable, cost-effective, and user-friendly fluoride detector.


Asunto(s)
Fluoruros , Fluorosis Dental , Humanos , Fluoruros/análisis , Agua/análisis , Monitoreo del Ambiente , Abastecimiento de Agua
11.
Pol Merkur Lekarski ; 51(6): 620-623, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38207063

RESUMEN

OBJECTIVE: Aim: The aim of the study was to determine the indicators of caries and its complications in the temporary teeth of children who permanently live in a region with a high fluoride content in drinking water. PATIENTS AND METHODS: Materials and Methods: It was examined with the definition of caries and its complications 277 children in the age range from 2 to 13 years, who were born and permanently live in the urban-type settlement of Mashivka. The fluoride content in the drinking water of the settlement was 1.7-2.5 mg/l. RESULTS: Results: During the analysis of data from the survey of children who were born and permanently lived in the urban-type settlement of Mashivka, it was determined that the prevalence of caries of temporary teeth probably increases with age. Half of the 3-5-year-old children had caries-affected teeth, and temporary tooth caries reached the highest rates in 10-year-old children. It should be noted that a fifth of children in the youngest age group (3-5 years old) suffer from pulpitis and periodontitis of temporary teeth. CONCLUSION: Conclusions: The conducted examination of children urban-type settlement of Mashivka confirms the opinion that the excessive content of fluorine in drinking water does not have a caries-protective effect, and the intensity of the process reaches the indicators characteristic of regions with its optimal content. Such a situation requires strengthening measures for both primary and secondary prevention of dental diseases.


Asunto(s)
Caries Dental , Agua Potable , Fluorosis Dental , Humanos , Preescolar , Niño , Adolescente , Fluoruros/efectos adversos , Fluorosis Dental/epidemiología , Flúor/análisis , Abastecimiento de Agua , Susceptibilidad a Caries Dentarias , Prevalencia , Caries Dental/epidemiología , Caries Dental/etiología
13.
J Water Health ; 20(7): 1126-1136, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35902994

RESUMEN

Although the presence of free-living amoebae (FLAs) in various water sources has been reported, few studies have been surveyed on their abundance in medical-unit and dental-unit water samples. The current study aimed to identify morphological and molecular characteristics of FLA isolates in the water samples of the dental unit in Iran. A total of 232 water samples were collected from 17 dental units. Then, filtration and cultivation were conducted on a non-nutrient agar (NNA) medium. Also, polymerase chain reaction (PCR) assay and sequencing were performed by using the genus/species-specific primers plus a common primer set on positive samples. One hundred and sixty-six samples were positive for FLA by the microscopic method, whereas 114 samples were positive by the molecular method with a common primer set. Considering the PCR assay with genus/species-specific primers, 23.27% (54/232) samples were identified as Acanthamoeba spp. (belonging to T4 genotype), 36.63% (85/232) as Vermamoeba vermiformis, and 1.72% (4/232) as Vahlkampfiidae family (Naegleria lovaniensis). These results highlight a need to improve filtration systems in dental units and periodic screenings for FLA in dental-unit water.


Asunto(s)
Acanthamoeba , Amoeba , Naegleria , Amoeba/genética , Agua , Abastecimiento de Agua
14.
Health Commun ; 37(2): 152-162, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-33016137

RESUMEN

The Safe Drinking Water Act Public Notification Rule requires that customers of public water systems (PWS) be informed of problems that may pose a risk to public health. Boil water advisories (BWA) are a form of communication intended to mitigate potential health risks. The Centers for Disease Control and Prevention (CDC) developed guidance for BWAs. We examined how local US news media incorporate the CDC's guidelines when reporting on BWAs. A content analysis of 1040 local news media articles shows these reports did not consistently incorporate CDC guidelines. Overall, 89% of the articles communicated enough information for readers to determine if they were included in the impacted area. Articles that included at least some of the CDC's instructions for boiling water were likely (p < .001) to include other risk information, such as the functions for which water should be boiled (e.g., drinking, brushing teeth) and that bottled water could be used as an alternative source. However, this information was included in only 47% of the articles evaluated. Results suggest public notifications often do not serve the public need for clear risk communication.


Asunto(s)
Agua Potable , Abastecimiento de Agua , Centers for Disease Control and Prevention, U.S. , Comunicación , Humanos , Medios de Comunicación de Masas , Estados Unidos
15.
Community Dent Health ; 39(2): 106-112, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34982862

RESUMEN

OBJECTIVES: Contemporary research, surveillance and monitoring of water fluoridation requires an understanding of the population coverage of this intervention. The aims of this research are to create the first publicly available record of water fluoride concentrations in England and to describe and visualise the observed variation in water fluoride concentrations and optimal fluoridation (⟩/= 0.7 mg F/L) between 2009-2020. BASIC RESEARCH DESIGN: Routine water quality sampling data were requested from water companies in England from 2009-2020 under the provisions of the Environmental Information Regulations 2004. Fluoride concentrations of Water Supply Zones (WSZs) were assigned to Lower Super Output Areas (LSOAs) using population-weighted centroids. RESULTS: Between 2009-2020 4247 LSOAs (12.9%) had an annual mean water fluoride concentration of ⟩/= 0.7 mg F/L in at least one year, and 3019 LSOAs (9.1%) had a grand mean fluoride concentration of ⟩/= 0.7 mg F/L. Coverage of optimal fluoridation varied over time; from 10.9% of LSOAs in 2014 to 6.3% in 2016. DISCUSSION: This study confirms previous work identifying variability in the coverage and achieved concentrations of water fluoridation programmes. The current provision for accessing, collating and utilising these data are a barrier to essential monitoring, surveillance and research. An annually maintained and publicly accessible database of water fluoride concentrations is urgently required.


Asunto(s)
Fluoruración , Fluoruros , Inglaterra , Fluoruros/análisis , Humanos , Abastecimiento de Agua
16.
J Environ Manage ; 317: 115510, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35751294

RESUMEN

Stormwater is a major contributor to microplastic (MP) pollution in the aquatic environment. Although MPs are associated with many toxicological effects, their levels in stormwater are not regulated. This review compared the effectiveness of different MP removal technologies from stormwater runoff and examined the performance of typical stormwater treatment systems for MP removal to assess possible MP pollution control via stormwater management. Bioretention and filtration systems performed similarly with 84-96% MP removal efficiencies. Despite the limited number of studies that focused on wetlands and retention ponds, preliminary data suggested potential for MP removal with efficiencies of 28-55% and 85-99%, respectively. Despite the higher efficiency of bioretention and filtration systems, their removal efficiency of fibrous MPs was not optimal. Furthermore, wetlands were less effective in removing MPs than retention ponds, although the limited data might lead to an inaccurate representation of typical performances. Therefore, more research is required to arrive at definitive conclusions and to investigate alternative treatment options, such as ballasted sand flocculation, flotation, and biological degradation, and evaluate the effectiveness of bioretention and filtration for MPs <100 µm.


Asunto(s)
Microplásticos , Purificación del Agua , Plásticos , Lluvia , Abastecimiento de Agua
17.
Environ Geochem Health ; 44(3): 1129-1136, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34173906

RESUMEN

Prolonged exposure to higher concentrations of fluoride (> 1.5 mg/L) is associated with dental and skeletal fluorosis. The effects of fluoride on dental and skeletal system have been studied extensively; however, the neurological consequences of fluoride in population-based studies are limited. The study aims to assess the epidemiology of neurological and other manifestations of fluorosis among rural populations living in the Main Ethiopian Rift valley. In this cross-sectional study, we enrolled 316 individuals from 23 rural communities in the Main Ethiopian Rift valley. Fluoride concentration was measured in drinking water samples collected from 23 community wells. Association between fluoride concentrations and clinical features of fluorosis was assessed using student t test, chi square, multivariable regression using adjusted odds ratio (OR). The mean fluoride concentration in the drinking water was 6.8 ± 4.3 mg/L (range: 0.3-15.5 mg/L). At least one clinical sign of skeletal fluorosis was observed in 54.4% (n = 175) of the study participants. Headache and joint pain reported by 67.1% and 56.3% of the participants as the most common neurological manifestation, and skeletal fluorosis symptom, respectively. The mean fluoride level was higher for those individuals who reported paresthesia compared to those with no-paresthesia. Loss of appetite, constipation, and fatigue were reported by 48.0%, 45.6%, and 56.6% of the participants, respectively. Signs of crippling fluorosis were observed in small proportion (1.6%) of the participants. Individuals who reported headache are most likely exposed to higher fluoride concentrations in drinking water compared to those reported no-headache (p < 0.001). The study demonstrates high prevalence of neuro-medical manifestations of fluorosis in population living in the Main Ethiopian Rift valley. Fluoride concentration in drinking water and joint pain were independent predictors of fluorosis.


Asunto(s)
Agua Potable , Intoxicación por Flúor , Fluorosis Dental , Estudios Transversales , Intoxicación por Flúor/epidemiología , Fluoruros/efectos adversos , Fluorosis Dental/epidemiología , Fluorosis Dental/etiología , Humanos , Prevalencia , Abastecimiento de Agua
18.
Environ Monit Assess ; 194(5): 327, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35381961

RESUMEN

Fluoride concentrations of 0.5 mg/L in drinking water are considered useful for dental caries prevention. However, fluoride concentrations higher than 1.2 mg/L in water can pose a risk of dental fluorosis due to high exposure to fluoride. The objective is to determine the fluoride concentration in water from aqueducts of different Colombian municipalities of Cauca (Popayán, Coconuco, and Puracé) to assess the fluoride dietary intake from the consumption of this water. A total of 66 water samples have been taken from Popayán, Coconuco, and Puracé. Fluoride content was determined by fluoride ion-selective electrode (ISE) potentiometry. The fluoride concentrations recorded in Coconuco and Puracé water were ≤ 0.002 mg/L. The mean fluoride content recorded in the Popayán water was 0.42 mg/L, with its highest concentration in Cauca River water (0.83 mg/L). Considering the admissible intake values, the water from Popayán confers remarkable fluoride intakes, especially in children with high percentages of contribution to the admissible daily intake (46.7% to 7- to 12-month children and 41.5% to 1- to 3-year children). The fluoride content in the water of Coconuco and Puracé does not reach an optimal value (< 0.5 mg/L) for the protective effect against dental caries, while the water of the main Cauca River basin does reach the optimal value. Likewise, the intake of fluoride from the consumption of the analyzed water does not confer any health risk. However, the implementation of monitoring systems for fluoride levels is recommended in order to safeguard the consumer's health.


Asunto(s)
Caries Dental , Agua Potable , Fluorosis Dental , Niño , Colombia , Monitoreo del Ambiente , Fluoruros/análisis , Humanos , Ríos , Abastecimiento de Agua
19.
Gen Dent ; 70(6): 41-45, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36288074

RESUMEN

Optimal exposure to fluoride and calcium from tap water is beneficial for dental caries prevention. Water fountains may be an important source of drinking water in work and educational settings. The aims of this study were to quantify the fluoride and calcium concentrations of drinking water samples collected from public water fountains on the Indiana University-Purdue University Indianapolis campus; compare the fluoride and calcium concentrations in water collected at 2 different times; and determine whether the presence or absence of a visible external filter affects fluoride and calcium concentrations. Ninety samples were collected from 45 water fountains accessible to the public, and 90 duplicate samples were collected 1 month later. A fluoride ion-selective electrode was used in conjunction with an ion-specific meter to determine fluoride concentration, while atomic absorption spectrometry in an air-acetylene flame was implemented to quantify the calcium concentration. The fluoride and calcium concentration of drinking water samples displayed ranges of 0.62 mg/L to 0.97 mg/L and 56.61 mg/L to 89.11 mg/L, respectively. The concentrations of fluoride and calcium in drinking water were slightly lower at the second collection period (P < 0.001; Wilcoxon signed rank test). No statistically significant differences were observed in the fluoride or calcium concentration of drinking water collected from water fountains with an external filter cartridge in comparison with fountains that did not have a filter. Fluoride concentrations were within the optimal range recommended by the US Public Health Service for fluoridated drinking water, and calcium concentrations were consistent with those reported in previous surveillance studies.


Asunto(s)
Caries Dental , Agua Potable , Humanos , Fluoruros/uso terapéutico , Abastecimiento de Agua , Calcio , Universidades , Alquinos/análisis
20.
Environ Sci Technol ; 55(3): 2076-2086, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33435682

RESUMEN

The presence of biopolymers in surface waters and their significance for potable water supply have received little attention previously owing to their low concentrations. In this paper, we present the results of an extensive study that has investigated the role and benefits of biopolymers during the purification of surface water with reference to their specific biological and physico-chemical properties. Using samples collected from two representative surface waters in China and the United Kingdom, macromolecular biopolymers were separated and concentrated for subsequent investigation of their role in coagulation, metal ion adsorption, and membrane separation. Our results show that biopolymers significantly improve the antifouling capability of membrane nanofiltration, in combination with the enhanced conventional coagulation performance and additional security against several unhealthy metal pollutants (e.g., Fe, Al, and Cr). We believe this is the first study that reveals the versatile benefits and the fate of natural biopolymers in surface water purification processes.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Biopolímeros , China , Reino Unido , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua
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