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1.
Sensors (Basel) ; 22(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36236229

RESUMO

Groundwater resource assessment and forecasting in mountain areas requires the monitoring of two conditions, local meteorological conditions, and springs' groundwater parameters. The reliability of the monitoring data and conditions are linked to the technical instrumentation, multiparametric probes, and sensors. This paper presents a set of attractive tools and sensors for springs' groundwater resource monitoring and assessment in mountain basins. Data from the combination of weather station sensors with spring flow-rate instruments, installed in the alpine Mascognaz basin, can guarantee an entire understanding of how one set of parameters can affect other results, defining consequential cause-and-effect relationships. Since a large part of the Alpine groundwater bodies are exploited for drinking purposes, understanding the evolution of their rechange processes requires making the right economic and instrumental investments aimed at using them according to forecast predictions and sustainable development goals.


Assuntos
Água Subterrânea , Nascentes Naturais , Compreensão , Monitoramento Ambiental , Reprodutibilidade dos Testes , Tempo (Meteorologia)
2.
Zootaxa ; 5169(5): 472-480, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-36095430

RESUMO

A new monotypic genus of freshwater snail from late Holocene spring deposits in Viesca, Coahuila (Mexico), is described based on shell morphology. Spinopyrgus luismaedai n. gen. et n. sp. has two to three carinate shells with long and wide shovel-shaped spines, strong axial ridges and a pointed protoconch. All sculptural ornamentations on the teleoconch are part of the calcareous shell material and not projections of the periostracum. This combination of shell features and their almost marine-like appearance is unknown among North American recent and fossil freshwater snails. Because of its shell characteristics, we placed the new genus tentatively in the Cochliopidae. The springs of Viesca dried up in the second half of the 20th century so that any living occurrence of this species in neighboring areas is unlikely, rendering the new genus and species possibly extinct.


Assuntos
Nascentes Naturais , Caramujos , Animais , Fósseis , Água Doce , México
3.
Sci Rep ; 12(1): 7679, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538207

RESUMO

As a traditional water source, springs are vital for Himalayan communities and it is essential to consciously focus on springs conservation. We report oxygen isotopes (δ18O) of spring water before, within, and after the tectonically active zones of the Alaknanda Valley, Uttarakhand. Higher variation of δ18O in the spring waters is found in highly tectonically disturbed zone i.e., Zone-2 with δ18O range - 4.9‰ to - 9.0‰ compared to tectonically less disturbed zones: Zone-1 and Zone-3 with δ18O value range - 7.9‰ to - 9.9‰ and - 7.4 to - 10.2‰ respectively. We hypothesize that the highly active thrust zones (Zone-2) with increased permeability compared to other Zones, manifested as greater spring density, results in higher water recharge in Zone-2. Very high to high spring density stretches are dominant in Zone-2 compared to Zone-1 and Zone-3. Stretches in Zone-2 with high spring density formed due to its highly tectonically active nature leads to the higher isotopic variation in Zone-2. The study also identifies the geosystem services provided by thrust zones as water resources to the local people and need of conservation modalities to manage the spring water resources in the thrust zones.


Assuntos
Monitoramento Ambiental , Nascentes Naturais , Meio Ambiente , Monitoramento Ambiental/métodos , Humanos , Isótopos de Oxigênio/análise , Água
4.
PLoS One ; 17(5): e0264501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35511881

RESUMO

In many respects, freshwater springs can be considered as unique ecosystems on the fringe of aquatic habitats. This integrates their uniqueness in terms of stability of environmental metrics. The main objective of our study was to evaluate how environmental variables may shape invertebrate diversity and community composition in different freshwater spring types and habitats within. In order to do so, we sampled invertebrates from 49 springs in Iceland, where we included both limnocrene and rheocrene springs. At each site, samples were taken from the benthic substrate of the spring ("surface") and the upwelling groundwater at the spring source ("source"). To collect invertebrates from the spring sources we used a modified method of "electrobugging" and Surber sampler for collecting invertebrates from the surface. In total, 54 invertebrate taxa were identified, mostly Chironomidae (Diptera). Chironomid larvae also dominated in terms of abundance (67%), followed by Ostracoda (12%) and Copepoda (9%). The species composition in the surface samples differed considerably between rheocrene and limnocrene springs and was characterised by several indicator species. Alpha diversity was greater at the surface of springs than at the source, but the beta diversity was higher at the source. Diversity, as summarized by taxa richness and Shannon diversity, was negatively correlated with temperature at the surface. At the source, on the other hand, Shannon diversity increased with temperature. The community assembly in springs appears to be greatly affected by water temperature, with the source community of hot springs being more niche-assembled (i.e., affected by mechanisms of tolerance and adaptation) than the source community of cold springs, which is more dispersal-assembled (i.e., by mechanisms of drift and colonization).


Assuntos
Fontes Termais , Nascentes Naturais , Animais , Biodiversidade , Ecossistema , Água Doce , Invertebrados
5.
PLoS One ; 17(5): e0268252, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35522687

RESUMO

Turbidite successions can behave either as aquitards or aquifers depending on their lithological and hydraulic features. In particular, post-depositional processes can increase rock permeability due to fracture development in the competent layers. Thus, at a local scale, turbidite systems warrant further detailed investigations, aimed at reconstructing reliable hydrogeological models. The objective of this work was to investigate from the hydrogeological perspective a turbiditic aquifer located in southern Italy, where several perennial and seasonal springs were detected. Considering the complex hydrodynamics of these systems at the catchment scale, to reach an optimal characterization, a multidisciplinary approach was adopted. The conceptual framework employed microbial communities as groundwater tracers, together with the physicochemical features and isotopic signature of springs and streams from water samples. Meanwhile, geophysical investigations coupled with the geological survey provided the contextualization of the hydrogeological data into the detailed geological reconstruction of the study area. This modus operandi allowed us to typify several differences among the samples, allowing identification of sources and paths of surface water and groundwater, along with diffuse groundwater outflow along streams. As a final result, a hydrogeological conceptual model was reconstructed, underlining how at a very local scale the lithologic, hydraulic, and geomorphological heterogeneity of the studied relief can lead to an improved hydrogeological conceptual model compared to that of other turbidite systems. These results open new questions about the hydrogeological behavior of turbiditic aquifers, which could be pivotal in future research. In fact, these systems could support relevant ecosystems and anthropic activities, especially where climate change will force the research of new (and probably less hydrogeologically efficient) water sources.


Assuntos
Água Subterrânea , Nascentes Naturais , Ecossistema , Monitoramento Ambiental , Água Subterrânea/química , Água
6.
Sci Total Environ ; 838(Pt 2): 156041, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35597350

RESUMO

Over the last several decades, rising nitrate concentrations in springs discharging from north Florida's karstic Upper Floridan Aquifer have coincided with proliferation of algae in Florida spring runs and subsequent ecosystem degradation. As agriculture and development are primary contributors to groundwater nitrate and are predicted to continue expanding, understanding unique contributions and transmission pathways of nitrate pollution is vital to restoring impaired spring ecosystems. In this study, we use statistics and signal processing to analyze continuous nitrate timeseries data collected over five years at four north Florida springs. We quantified a significant, low-frequency annual signal in nitrate concentrations superimposed on increasing nitrate trends. We show nitrate concentrations at springs increase during the rainy season, potentially in response to recharge and seasonal fertilizer application. Thus, we suggest seasonal fluctuations observed in nitrate concentrations are caused by increased recharge of nutrient-rich soil waters through fractures that deliver water on relatively short timescales to conduits during the rainy season. We further speculate the steady, monotonically increasing concentration is maintained by accumulation of Nitrogen as slow flow through matrix porosity through the remainder of the year. Seasonal nitrate concentrations resulting from flow through karst aquifers may thus be poorly simulated using equivalent porous media models that are increasingly being used for nutrient management, because they do not capture heterogenous flow and transport dynamics.


Assuntos
Água Subterrânea , Nascentes Naturais , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental/métodos , Nitratos/análise , Poluentes Químicos da Água/análise
7.
J Fluoresc ; 32(4): 1357-1367, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35377047

RESUMO

A propylimidazole functionalized coumarin derivative (IPC) was fabricated for the first time and applied as a dual responsive fluorescent chemoprobe for sensitive and selective recognition of picric acid (PA) and Fe3+. Strong fluorescence quenching phenomena of the IPC were observed in H2O/ACN (5/95, v/v) medium (λem=408 nm) upon the additions of Fe3+or PA. The fabricated dual responsive IPC offered good selectivity and sensitivity with the low limit of detection values (0.92 µM for PA and 0.22 µM for Fe3+) lower than the acceptable amounts of Fe3+ and PA by the international official authorities. The validation study for the chemoprobe IPC for PA and Fe3+ was also performed. The interaction phenomena of IPC with PA and Fe3+ based on the findings of a range of experiments were considered and DFT computations were done to verify their recognition mechanisms. The sensing phenomena of IPC towards PA (1:1) and Fe3+ (3:1) were confirmed by the MALDI TOF-MS, FT-IR, 1H-NMR titration and Job's methods. Furthermore, the compound IPC was effectively applied as a fluorescent sensor for Fe3+ and PA detection in real natural spring water samples.


Assuntos
Nascentes Naturais , Água , Cumarínicos , Corantes Fluorescentes/química , Picratos , Espectrometria de Fluorescência/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
8.
J Water Health ; 20(4): 737-754, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35482389

RESUMO

The scarcity of drinking water has become a bitter reality in many countries. The gap between demand and supply of water has been increasing exponentially year by year. Deforestation, vigorous use of groundwater for agricultural practices, and pollution of our present water resources such as rivers, lakes, and wells are triggering the freshwater scarcity problem. Ninety percent of people in Uttarakhand depend on springs for their daily life activities. In such a case, the quality and quantity of spring water should be a prime topic to be focussed on. In the Kumaon region of Uttarakhand, spring water quality is good but there is an issue with its availability, especially in summer. This review paper details the studies that have been conducted on nutrient status, hardness, heavy metals, and the presence of microbiological diversity in spring water. It also uncovers information on some critical springs, geological settings of their aquifers, and the steps that have been adopted to rejuvenate the spring. Some other measures have been carried out by the government and local communities for springs' revival and their improvement in discharge rate, including the construction of percolation pits, contour trenches, check dams, and improvement of water resources. It has been observed among the analyzed sample that the Kumaon region is dominated by arsenic, cadmium, chromium, and lead, whereas aluminum, barium, cobalt, and manganese are more in the Garhwal region. Apart from springs, this review paper also reveals the physicochemical characteristics of the spring-fed rivers and lakes of the Kumaon region.


Assuntos
Água Subterrânea , Nascentes Naturais , Humanos , Lagos , Rios , Qualidade da Água
9.
Ground Water ; 60(6): 801-807, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35452131

RESUMO

Simulating the interaction of groundwater with surface water networks using traditional boundary packages available with MODFLOW-USG can be challenging for complex systems. Often several package types are required as they are typically purpose built. Moreover, these packages generally do not interact with one another which complicates accounting of groundwater discharge at different points within the system. Here, we demonstrate that the connected linear network (CLN) package of MODFLOW-USG, and advances therein in USG-Transport, can be used to simulate groundwater interaction with a complex surface water network comprised of creeks, ponds, wetlands, and springs, in a manner that is comparable with these other packages, but with additional benefits, including explicit routing of water between the features.


Assuntos
Água Subterrânea , Nascentes Naturais , Movimentos da Água , Água , Modelos Teóricos
10.
Appl Radiat Isot ; 184: 110203, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35366603

RESUMO

A computational simulation of alpha-particle expansion, emitted by 222Rn naturally diluted in the water of a spring located in the state of Puebla Mexico, is presented. This simulation provided information on the volume of expansion of the alpha particles in the vicinity of the spring and thus awareness if there was a radiological risk for the users or the population that lived near to it. Before performing the simulation, several measurements were made to water samples with a dynamic measurement system. This in order to know the level of radon concentration and compare the results obtained with the levels recommended by the United States Environmental Protection Agency (US-EPA) and the World Health Organization (WHO). In addition, to know if there was a radiological risk due to the presence of gamma emitting radionuclides, complementary water analyses were carried out using gamma-ray spectrometry techniques. The simulation was developed using the scientific software of particle interaction with matter, Geant4. The different variables declared for the software parameters are presented in this document. The results of the radon measurements in the water and the computational simulation, determined that there was no radiological risk due to alpha radiation. Furthermore, the results from the gamma-ray spectrometer showed that there was no presence of other hazardous radionuclides in the water.


Assuntos
Água Potável , Nascentes Naturais , Monitoramento de Radiação , Radônio , Poluentes Radioativos da Água , Partículas alfa , Água Potável/análise , México , Monitoramento de Radiação/métodos , Radioisótopos/análise , Radônio/análise , Estados Unidos , Poluentes Radioativos da Água/análise
11.
Sci Total Environ ; 825: 153827, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35157871

RESUMO

Karst aquifers are globally important source of drinking water and harbor specific ecosystems that are vulnerable to anthropogenic contamination. This paper provides insights into the occurrence and ecotoxicological characterization of 21 emerging contaminants (ECs) detected in the karst catchment of Jadro and Zrnovnica springs (Dinarides, Croatia). Karst springs used for water supply, surface water, and groundwater were sampled during seven campaigns. The ECs concentration levels ranged from 0.3 ng/L (tramadol in Jadro spring) to 372 ng/L (1H-benzotriazole in Cetina River). DEET was the most frequently detected ECs with an average concentration of around 50 ng/L in both surface water and groundwater. To prioritise detected ECs, their persistence (P), bioaccumulation (B), mobility (M) and toxicity (T) were assessed based on in silico strategy for PBT assessment and recently developed REACH PMT guidelines. PBT scores ranging below the threshold of 0.5, indicated non-PBT compounds of expected low concern. However, only 4 out of 21 detected ECs were not assessed as PMT/vPvM. Concerningly, 20 ECs were categorised as very mobile. Karst springs exhibited larger proportions of ECs meeting PMT/vPvM criteria than surface water. To characterise the contamination extent and estimate the incidence of adverse effects of detected ECs, a preliminary environmental risk assessment (ERA) was conducted. Most ECs posed no environmental risk with RQ values predominantly below 0.01. The total risk quotient RQsite accentuated Cetina River as having the highest risk compared to other sampling sites. This is the first study on ECs in Croatian karst, contributing to a growing need to understand the impacts of emerging contaminants in karst aquifers, which are still largely unexplored.


Assuntos
Água Subterrânea , Nascentes Naturais , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Água , Poluentes Químicos da Água/análise
12.
Environ Microbiol Rep ; 14(2): 308-319, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35199456

RESUMO

Reduced substrates produced by the serpentinization reaction under hydration of olivine may have fuelled biological processes on early Earth. To understand the adaptive strategies and carbon metabolism of the microbes in the serpentinizing ecosystems, we reconstructed 18 draft genomes representing dominant species of Omnitrophicaeota, Gammaproteobacteria and Methanobacteria from the Manleluag serpentinizing spring in Zambales, Philippines (hyperalkaline and rich in methane and hydrogen). Phylogenomics revealed that two genomes were affiliated with a candidate phylum NPL-UPA2 and the references of all our genomes were derived from ground waters, hot springs and the deep biosphere. C1 metabolism appears to be widespread as most of the genomes code for methanogenesis, CO oxidation and CO2 fixation. However, likely due to the low CO2 concentration and election acceptors, the biomass in the spring was extremely low (<103 cell/ml). Various Na+ and K+ transporters and Na+ -driving ATPases appear to be encoded by these genomes, suggesting that nutrient acquisition, bioenergetics and normal cytoplasmic pH were dependent on Na+ and K+ pumps. Our results advance our understanding of the metabolic potentials and bioenergetics of serpentinizing springs and provide a framework of the ecology of early Earth.


Assuntos
Euryarchaeota , Nascentes Naturais , Carbono/metabolismo , Ecossistema , Euryarchaeota/metabolismo , Nascentes Naturais/microbiologia , Filipinas
13.
J Water Health ; 20(1): 193-204, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35100167

RESUMO

Infection with Acanthamoeba spp. may result in granulomatous amoebic encephalitis and Acanthamoeba keratitis. Water is an important habitat where Acanthamoeba species thrive. Therefore, studying the occurrence of this free-living amoeba in water sources will help understand the infection dynamics. The aim of the study was to survey and report on the presence of Acanthamoeba spp. in water resources from the Ordu and Giresun provinces in Black Sea. Acanthamoeba spp. was found in 1/17 natural spring water samples from Ordu and in 2/18 from Giresun. Acanthamoeba species were not detected in any of the investigated tap water samples. Sequencing of the (SSU) rDNA gene resulted in the identification of haplotype I (Acanthamoeba genotype: KJ094684). T4 (8.6%) was the only isolated genotype in both Ordu and Giresun provinces. This is the first report of Acanthamoeba T4 genotype in natural spring water resources in the Black Sea. The occurrence of Acanthamoeba species in natural spring water sources should be considered as a potential risk for human infection, especially to high-risk populations.


Assuntos
Acanthamoeba , Nascentes Naturais , Acanthamoeba/genética , Mar Negro , Genótipo , Humanos , Turquia , Recursos Hídricos
14.
Environ Monit Assess ; 194(2): 87, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35020087

RESUMO

Springs are a significant source of high quality and perennial freshwater supply for remote communities and sustain rich biodiversity and ecosystems in the Himalayas. About 60-70% of the Himalayan population directly depends on springs to meet their domestic and livelihood needs. Despite that, decline in approximately 60% of low discharge springs have been reported in the last couple of decades. In addition, nitrates and faecal coliform contamination linked to septic tanks, open defecation, and fertiliser application have been reported. A high degree of urbanization with 500 growing townships and 8-10 large cities has further threatened the sustenance of these vital resources, causing a severe water crisis in the Himalayas. Spring rejuvenation can enhance water access and livelihoods and help achieve several sustainable development goals (SDGs). However, multiple challenges hinder the success of such initiatives. A fundamental limitation is the poor understanding of complex groundwater (spring) systems and their interactions with human societies. This review identified crucial knowledge gaps by synthesizing available knowledge on springs and revival efforts from peer-reviewed journals and reports by practitioners and governing bodies. The review also highlights the limitations of spring revival approaches and recommends future management options. There is a critical lack of comprehensive data as a large research on the Himalayan spring systems results from small-scale spring centric studies focussing primarily on hydrology. In contrast, the impacts of hydrogeology, ecology, socio-economics and developmental activities on springs are less explored. Lack of scientific inputs on the hydrogeological regime and limited support by the state is a barrier to scaling spring rejuvenation programs. Long term monitoring, location-specific mapping of local hydrogeological and socio-economic settings at aquifer scale and collaborations among different stakeholders are essential to facilitate holistic knowledge development on spring systems and successful spring revival. The authors recommend ensuring sustenance by recognizing the value of springs in the mainstream programs and policies and develop appropriate management framework for the management of spring systems.


Assuntos
Água Subterrânea , Nascentes Naturais , Ecossistema , Monitoramento Ambiental , Humanos , Água
15.
Environ Geochem Health ; 44(7): 2021-2035, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33844102

RESUMO

The Island of Ischia, one of the Italian active volcanoes, is a famous tourist resort for spa treatments. Spas are supplied by withdrawals from groundwaters which are characterized by a wide range of chemical compositions, salinity and temperature. In natural conditions, the hydrogeological system is recharged by rainfall and by deep fluids; the discharge is towards the sea and the springs. During the peak of the tourist season, when approximately 240 wells are operating simultaneously, a significant additional recharge of the aquifers derives from seawater and from upwelling increase in deep fluids. Although this does not compromise the availability of groundwater, the pumping often determines variation in composition and temperature of groundwater over time. Conversely, the maintenance of a stable quality of thermal waters represents one of the requirements for their therapeutic use in the spas. The study aims to establish game-theoretical modeling of the optimal sustainable exploitation of the groundwater resources of the island by competing users (spas) falling in the same flow tube of the aquifer. In the game the spas are the players, the strategy of a player consists of a fixed pumping rate and daily time durations of pumping, and the player's utility or payoff is proportional to the total quantity of withdrawn thermal water in a given time period. A special constrained Pareto optimal strategy choice is obtained, considered as a cooperative solution of the game. Pareto optimality means that there is no other strategy choice that makes one player better off without making some other player worse off.


Assuntos
Água Subterrânea , Nascentes Naturais , Água Subterrânea/química , Modelos Teóricos , Água , Poços de Água
16.
Environ Geochem Health ; 44(7): 1971-1994, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33660150

RESUMO

In the context of global climate change, understanding the relationships between climate and groundwater is increasingly important. This study in the NW Alps represents the first regional-scale investigation of the groundwater feature variation in mountain aquifers due to climate variability. The analysis of groundwater temperature and discharge in 28 natural mineral water springs and meteorological parameters (rainfall and air temperature) permitted us to evaluate the annual behaviour and possible trends of these parameters during the period from 2001 to 2018. The air temperature showed a positive trend almost everywhere, with a rise of up to 0.03 °C/year. In contrast, only ten springs showed a positive trend for groundwater temperature, but with the smallest rates of increase. Moreover, despite the substantial stability of the rainfall amount, 50% of the analysed springs showed a trend (29 and 21% for positive and negative trends, respectively) with low discharge variations. Finally, cross-correlation analyses proved the close relationship between air and groundwater temperatures, with a time lag between 0 and 3 months, and between spring discharge and air temperature, with a time lag between 1 and 3 months. In particular, spring discharge is closely connected to snow melting in spring and subordinate to rainfall. These results highlight the existing correlations between spring discharge and various meteorological and topographic parameters in the studied mountain area and provide a preliminary framework of the impacts of climatic variability on the availability and temperature of the exploited water resources.


Assuntos
Água Subterrânea , Águas Minerais , Nascentes Naturais , Mudança Climática , Temperatura
17.
J Med Virol ; 94(3): 985-993, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34672374

RESUMO

The objective of this study was to validate the use of spring water gargle (SWG) as an alternative to oral and nasopharyngeal swab (ONPS) for SARS-CoV-2 detection with a laboratory-developed test. Healthcare workers and adults from the general population, presenting to one of two COVID-19 screening clinics in Montréal and Québec City, were prospectively recruited to provide a gargle sample in addition to the standard ONPS. The paired specimens were analyzed using thermal lysis followed by a laboratory-developed nucleic acid amplification test (LD-NAAT) to detect SARS-CoV-2, and comparative performance analysis was performed. An individual was considered infected if a positive result was obtained on either sample. A total of 1297 adult participants were recruited. Invalid results (n = 18) were excluded from the analysis. SARS-CoV-2 was detected in 144/1279 (11.3%) participants: 126 from both samples, 15 only from ONPS, and 3 only from SWG. Overall, the sensitivity was 97.9% (95% CI: 93.7-99.3) for ONPS and 89.6% (95% CI: 83.4-93.6; p = 0.005) for SWG. The mean ONPS cycle threshold (Ct ) value was significantly lower for the concordant paired samples as compared to discordant ones (22.9 vs. 32.1; p < 0.001). In conclusion, using an LD-NAAT with thermal lysis, SWG is a less sensitive sampling method than the ONPS. However, the higher acceptability of SWG might enable a higher rate of detection from a population-based perspective. Nonetheless, in patients with a high clinical suspicion of COVID-19, a repeated analysis with ONPS should be considered. The sensitivity of SWG using NAAT preceded by chemical extraction should be evaluated.


Assuntos
COVID-19 , Nascentes Naturais , Adulto , COVID-19/diagnóstico , Humanos , Antissépticos Bucais , Nasofaringe , SARS-CoV-2/genética , Saliva , Manejo de Espécimes/métodos , Água
18.
Environ Sci Pollut Res Int ; 29(6): 8253-8268, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34482481

RESUMO

The World Health Organization lists cadmium (Cd) as one of the top ten chemicals of public health concern. Cd is toxic at relatively low exposure levels and has acute and chronic effects on both health and the environment. In this study, we investigate a suite of data-driven methods that could assist decision-makers in estimating Cd levels in water springs, and in identifying polluting sources. Machine learning (ML) regression models were used to identify sources of contamination and predict Cd levels based on support vector machines and a variety of tree-based models, including Random Forests, M5Tree, CatBoost, and gradient boosting. Feature selection analysis revealed that heavy traffic and distance to a major power plant in the sampled area play a leading role in springs Cd contamination, together with precipitation levels and average of slopes of the closest waste dumps upstream to sampled springs. Our best performing ML model was the Adaboost regression tree using all the features (RMSE = 19.36, R^2 = 0.64). Our findings highlight the effectiveness of predictive data-driven modeling in addressing environmental challenges, particularly in high-risk areas with low resources.


Assuntos
Cádmio , Nascentes Naturais , Poluição Ambiental , Aprendizado de Máquina , Água
19.
Environ Monit Assess ; 194(1): 30, 2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34921632

RESUMO

The quality of spring water and its suitability for human consumption is determined by examining its physicochemical and microbiological characteristics. Preliminary investigations were conducted to determine the potability of seven traditionally used springs in the highly populated hill town of Bhaderwah in Union Territory of Jammu and Kashmir, India. The water analysis was performed for various physico-chemical and microbial parameters during April 2019-March 2020. Water temperature, TDS, EC, pH, DO, free CO2, total alkalinity, total hardness, Ca2+, Mg2+, Na+, K+, CO32-, HCOֿ3, Cl‾, NOֿ3, PO43-, SO42-, total coliforms, and thermotolerant coliforms were all measured. Eleven physical and chemical characteristics were used to generate the Water Quality Index. The Piper diagram demonstrated the predominance of Ca2+-HCOֿ3 water types, whereas the Schoeller diagram indicated that all springs had a similar lithological origin. The chemical composition of springs tested met the required criteria for drinking water quality. The microbiological indicators, on the other hand, did not satisfy the criteria except for Eidgah spring, which lacked thermotolerant coliforms. Our results on spring water potability indicate that the town's most dependable springs are susceptible to anthropogenic contamination and therefore need treatment prior to use. Apart from frequent monitoring, the responsible municipal corporation is expected to develop comprehensive plans to rehabilitate and revitalise these vulnerable drinking water sources.


Assuntos
Água Potável , Nascentes Naturais , Monitoramento Ambiental , Humanos , Índia , Qualidade da Água
20.
Sci Rep ; 11(1): 22429, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789791

RESUMO

Adequate water supply is one of the public health issues among the population living in low-income settings. Vibriosis remain a significant health challenge drawing the attention of both healthcare planners and researchers in South West districts of Uganda. Intending to clamp down the disease cases in the safest water deprive locality, we investigated the virulent toxins as contaminants and epidemiologic potentials of Vibrio species recovered from surface waters in greater Bushenyi districts, Uganda. Surface water sources within 46 villages located in the study districts were obtained between June and October 2018. Standard microbiological and molecular methods were used to analyse samples. Our results showed that 981 presumptive isolates retrieved cell counts of 10-100 CFU/g, with, with (640) 65% confirmed as Vibrio genus using polymerase chain reaction, which is distributed as follows; V. vulnificus 46/640 (7.2%), V. fluvialis 30/594 (5.1), V. parahaemolyticus 21/564 (3.7), V. cholera 5/543 (0.9), V. alginolyticus 62/538 (11.5) and V. mimicus 20/476 (4.2). The virulence toxins observed were heat-stable enterotoxin (stn) 46 (82.10%), V. vulnificus virulence gene (vcgCPI) 40 (87.00%), extracellular haemolysin gene {vfh 21 (70.00)} and Heme utilization protein gene {hupO 5 (16.70)}. The cluster analysis depicts hupO (4.46% n = 112); vfh (18.75%, n = 112); vcgCPI and stn (35.71%, & 41.07%, n = 112). The principal component analysis revealed the toxins (hupO, vfh) were correlated with the isolate recovered from Bohole water (BW) source, while (vcgCPI, stn) toxins are correlated with natural raw water (NRW) and open springs (OS) water sources isolates. Such observation indicates that surface waters sources are highly contaminated with an odds ratio of 1.00, 95% CI (70.48-90.5), attributed risk of (aR = 64.29) and relative risk of (RR = 73.91). In addition, it also implies that the surface waters sources have > 1 risk of contamination with vfh and > six times of contamination with hupO (aR = 40, - 66). This is a call of utmost importance to the population, which depends on these water sources to undertake appropriate sanitation, personal hygienic practices and potential measures that ensure water quality.


Assuntos
Toxinas Bacterianas/análise , Toxinas Bacterianas/genética , Nascentes Naturais/microbiologia , Vibrioses/prevenção & controle , Vibrio/genética , Vibrio/patogenicidade , Fatores de Virulência/análise , Fatores de Virulência/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Genes Bacterianos , Proteínas Hemolisinas/análise , Proteínas Hemolisinas/genética , Reação em Cadeia da Polimerase/métodos , Uganda/epidemiologia , Vibrio/classificação , Vibrioses/epidemiologia , Vibrioses/microbiologia , Virulência/genética
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