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1.
Water Environ Res ; 87(5): 414-24, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26460461

RESUMEN

The influents/effluents from Calgary's water resource recovery facilities and the surface water were analyzed for pharmaceuticals in the present study. The median concentrations in the effluents for the 15 targeted pharmaceuticals were within the range of 0.006 to 3.32 ppb. Although the wastewater treatment facilities were not designed to remove pharmaceuticals, this study indicates that the wastewater treatment processes are effective in removing some of the pharmaceuticals from the aqueous phase. The removal rate estimated can be 99.5% for caffeine, whereas little or no removal was observed for carbamazepine. Biodegradation, chemical degradation, and sorption could be some of the mechanisms responsible for the removal of pharmaceuticals. The drug residues in downstream surface water could be associated with incomplete removal of pharmaceuticals during the treatment process and may lead to concerns in terms of potential impacts on the aquatic ecosystem. However, this study does not indicate any immediate risks to the downstream aquatic environment.


Asunto(s)
Monitoreo del Ambiente/métodos , Preparaciones Farmacéuticas/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Abastecimiento de Agua/análisis , Alberta , Aguas del Alcantarillado/química
2.
J Water Health ; 13(3): 859-69, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26322772

RESUMEN

Trihalomethanes (THMs) were the first disinfection by-products discovered in drinking water and are classified as probable carcinogens. This study measures and models THMs formation at two drinking water distribution systems (WDS1 and WDS2) in Ahvaz City, Iran. The investigation was based on field-scale investigations and an intensive 36-week sampling program, from January to September 2011. The results showed total THM concentrations in the range 17.4-174.8 µg/L and 18.9-99.5 µg/L in WDS1 and WDS2, respectively. Except in a few cases, the THM concentrations in WDS1 and WDS2 were lower than the maximum contaminant level values. Using two-tailed Pearson correlation test, the water temperature, dissolved organic carbon, UV254, bromide ion (Br-), free residual chlorine, and chlorine dose were identified as the significant parameters for THMs formation in WDS2. Water temperature was the only significant parameter for THMs formation in WDS1. Based on the correlation results, a predictive model for THMs formation was developed using a multiple regression approach. A multiple linear regression model showed the best fit according to the coefficients of determination (R2) obtained for WDS1 (R2=0.47) and WDS2 (R2=0.54). Further correlation studies and analysis focusing on THMs formation are necessary to assess THMs concentration using the predictive models.


Asunto(s)
Modelos Químicos , Trihalometanos/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Irán , Estaciones del Año , Trihalometanos/química , Contaminantes Químicos del Agua/química
4.
Gig Sanit ; 94(3): 101-5, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26302572

RESUMEN

There have been performed the studies of the dimensional parameters of peroxide associates in drinking water, per- forming regulatory functions in cellular metabolism, that determine the character of the biological response of the human body to drinking water The direction of action of peroxide associates type Σ [(HO2-(*) ... OH-(*) (H2O) tp)]q, (where (H2O) tp is an associate with the tetragonal structure (Walrafen pentamer Is ice VI), q is the degree of association p--parameter of ion coordination) on the cellular structures of the organism is associated with their quantum properties, determining the macroscopic parameters of the electron wave packets. Research has confirmed the addressness of the nonlocal entering electron to certain cellular structures of the body, which is determined by the structural similarity of centers of condensation of electrons in the cells of systems and organs of the body with the parameters of the electron wave packets in the associates. Methodology for the estimation of the orientation of biological effect of the drinking water to the systems of the body on the base of the analysis of variations in heart rhythm under non-contact influence of water on the human body and its relationship with the dimensional parameters and peroxide activity of associates in drinking water can be suggested for the implementation of screening tests for drinking water quality, taking into account both the individualfeatures of responses of body systems to drinking water and its group action.


Asunto(s)
Agua Potable/normas , Calidad del Agua , Abastecimiento de Agua/análisis , Humanos
6.
Community Dent Health ; 32(1): 8-15, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26263586

RESUMEN

UNLABELLED: A positive association between dental fluorosis prevalence and fluoride (F) concentration in drinking waters has been detected in Gaza Strip. Total Daily Fluoride Retention (TDFR), and Fractional Urinary Fluoride Excretion (FUFE) indicate F body burden; important in assessing fluorosis risk in susceptible age groups. OBJECTIVE: 1, To determine and compare Daily Urinary Fluoride Excretion (DUFE) and FUFE of 3-4-year-olds living in lower (< 0.7), moderate (0.7-1.2) or higher (> 1.2 ) ppm F tap water areas; 2, To determine any relationship between i, DUFE and tap water F; ii, DUFE and Total Daily Fluoride Intake (TDFI); iii, TDFI and TDFR. METHODS: 24-hour urine and tap water samples were collected from 216 children exposed to lower (n = 81), moderate (n = 72), or higher (n = 63) tap water F. ANOVA with Tukey's Test and Pearson's correlation were used to examine differences in mean DUFE and FUFE and relationships between variables. RESULTS: Mean drinking water F was 0.11(sd 0.17), 0.14 (sd 0.28) and 0.38 (sd 0.63) ppmF respectively. Differences (p < 0.0001) in mean DUFEs (0.17 (sd 0.13), 0.25 (sd 0.15) and 0.38 (sd 0.23) mg/day respectively) and mean FUFEs (48 (sd 39)%, 47 (sd 31)% and 63(sd 76)%) were found (p < 0.05). Significant (p < 0.0001) positive correlations were found between DUFE and tap water F; DUFE and TDFI, and; TDFI and TDFR. CONCLUSION: DUFEs of children drinking waters with 0.11 and 0.14ppm F, represented low F usage. The group drinking 0.38ppm F water represented optimal F usage. The weak significant positive association of DUFE with home tap water F suggests low validity for tap water F in estimating F exposure.


Asunto(s)
Cariostáticos/análisis , Fluoruros/orina , Abastecimiento de Agua/análisis , Estatura , Peso Corporal , Cariostáticos/farmacocinética , Preescolar , Creatinina/orina , Agua Potable/análisis , Femenino , Fluoruros/análisis , Fluoruros/farmacocinética , Agua Subterránea/análisis , Humanos , Masculino , Medio Oriente
8.
J Toxicol Environ Health A ; 78(12): 761-77, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26090560

RESUMEN

The occurrence of phthalate esters (PE) was examined in biota, ambient water, and sediments of two man-made lakes (Asejire and Eleyele) in southwestern Nigeria. Five fish species (Tilapia zillii, Hepsetus odoe, Parachanna obscura, Chrysichthys nigrodigitatus, and Mormyrus rume) were analyzed for PE levels and used for calculating bioconcentration factors (BCF) and biota-sediment accumulation factors (BSAF). In addition, measured PE levels were thereafter used to calculate the phthalate pollution index (PPI) in biota and the environment. At both lakes, all sampled species had k-factor > 1, showing apparently normal growth and health condition. Higher PE levels were found in sediments compared with water at both lakes, with a pattern showing that di(2-ethylhexyl) phthalate (DEHP) was predominant PE. While there were no unique patterns of PE concentrations in both lakes, differences were observed in organ concentration patterns that were evident at both lakes. For T. zillii, the BSAF was higher for dibutyl phthalate (DBP) compared to diethyl phthalate (DEP) and lowest for DEHP. The concentration pattern demonstrated that DBP concentrated more in gills (BCF: 6.7), while DEHP concentrated more in liver (BCF: 15.2) of T. zillii at Asejire. At Eleyele, T. zillii liver and gills concentrated less DEP and DEHP. The PPI value was significantly higher in sediment with respective values of 0.27 and 0.44 at Asejire and Eleyele lakes compared with water with respective values of 0.1 and 0.18 at Asejire and Eleyele lakes. Overall, our findings suggest a broader environmental and human health implication of high PE levels in these lakes, since they provide vast water volumes that are used for municipal domestic water supply. Further, these lakes support intense artisanal fisheries, representing significant sources of aquatic food resources for neighboring communities.


Asunto(s)
Ácidos Ftálicos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Abastecimiento de Agua/análisis , Animales , Monitoreo del Ambiente , Peces , Agua Dulce , Sedimentos Geológicos/análisis , Humanos , Nigeria , Palaemonidae , Prevalencia , Especificidad de la Especie , Distribución Tisular
9.
Wei Sheng Yan Jiu ; 44(1): 82-5, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25958643

RESUMEN

OBJECTIVE: To investigate the arsenic levels in endemic arsenism in Datong City, Shanxi Province. METHODS: A total of 85 inhabitants from one village in endemic arsenism area in Datong City, Shanxi Province were collected as research subjects. The People's Republic of China health industry standard for endemic arsenism was used to identify and diagnosis the patients. Daily drinking water and soil were collected and detected by atomic fluorescence spectrometry. The content of vegetables were detected by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: In the study, 85 samples were collected. Arsenic concentration in the daily drinking water were 14.41 - 90.34 µg/L, and the median value was 43.88 µg/L. The arsenic concentration of vegetables were 0.001 - 0.771 mg/kg, and 43.04% of samples, were higher than the maximal permissible limit of As in food. The results that the arsenic concentration of vegetables constant changes in the leaf vegetables > tubers > fruit vegetables. The health risk of intaking arsenic pollution in vegetables up to 71.77%. The arsenic levels in village of four directions were not exceeded the Chinese standards. CONCLUSIONS: Arsenic concentration in drinking water and vegetables are high in waterborn endemic arsenicosis area of Shanxi province. Arsenic in drinking water has been considered as a primary cause of arsenism, but direct intake of arsenic from vegetables can not be ignored.


Asunto(s)
Intoxicación por Arsénico/epidemiología , Arsénico/análisis , Ecosistema , Enfermedades Endémicas , Contaminación Ambiental , Contaminantes Químicos del Agua/análisis , Arsénico/efectos adversos , Intoxicación por Arsénico/etiología , Intoxicación por Arsénico/prevención & control , China , Humanos , Verduras , Agua , Abastecimiento de Agua/análisis
11.
Glob J Health Sci ; 7(4): 286-94, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25946951

RESUMEN

The presence of heavy metals such as lead in drinking water resources can be dangerous for human because of toxicity and biological accumulation. The consumption of water or food which contains lead in high concentration can lead to prevent from Hemoglobin Synthesis (Anemia) and Kidney diseases. In this present study, the researcher collected 432 samples of bottled water in the popular marks in summer and winter from the surface of Bandar Abbas. The lead concentration was measured by atomic absorption Spectrophotometer in model DR2800 through the Dithizone method. CDI, R and HQ which are caused by lead for adult men, women and children, have been calculated and evaluated through the equations of EPA and WHO. The mean concentration of lead, which is 3.46± 0.47 µg/l, and its range, which is 1.9-17.6 µg/l, are lower than the guideline of WHO (10 µg/l) and MPC of EPA is (15 µg/l). But the 40 samples of the bottled water (9.2%) have the concentration higher than guideline WHO and 8 samples (1.85%) has the concentration higher than the permissible limits of the EPA. CDI in different age groups is as following manner: Children>adult men>adult women. CDI in children is more than twice as much as in the adult men and women. The R of lead for children (24E-7), adult men (11E-7) and for adult women (10E-7) are more than the acceptable level of R in EPA (1E-6) but less than the acceptable level of R in WHO (1E-4). Since HQ of adult men (34E-5), adult women (31E-5) and children (84E-5), is lower than 1, it can be said that the population of Bandar Abbas is in a safe area regarding the HQ of the bottled water's lead.


Asunto(s)
Carcinógenos/análisis , Agua Potable/análisis , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Adulto , Distribución por Edad , Análisis de Varianza , Niño , Femenino , Humanos , Irán , Masculino , Riesgo , Espectrofotometría Atómica , Abastecimiento de Agua/estadística & datos numéricos
12.
Proc Natl Acad Sci U S A ; 112(20): 6325-30, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25941400

RESUMEN

High-volume hydraulic fracturing (HVHF) has revolutionized the oil and gas industry worldwide but has been accompanied by highly controversial incidents of reported water contamination. For example, groundwater contamination by stray natural gas and spillage of brine and other gas drilling-related fluids is known to occur. However, contamination of shallow potable aquifers by HVHF at depth has never been fully documented. We investigated a case where Marcellus Shale gas wells in Pennsylvania caused inundation of natural gas and foam in initially potable groundwater used by several households. With comprehensive 2D gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-TOFMS), an unresolved complex mixture of organic compounds was identified in the aquifer. Similar signatures were also observed in flowback from Marcellus Shale gas wells. A compound identified in flowback, 2-n-Butoxyethanol, was also positively identified in one of the foaming drinking water wells at nanogram-per-liter concentrations. The most likely explanation of the incident is that stray natural gas and drilling or HF compounds were driven ∼ 1-3 km along shallow to intermediate depth fractures to the aquifer used as a potable water source. Part of the problem may have been wastewaters from a pit leak reported at the nearest gas well pad-the only nearby pad where wells were hydraulically fractured before the contamination incident. If samples of drilling, pit, and HVHF fluids had been available, GCxGC-TOFMS might have fingerprinted the contamination source. Such evaluations would contribute significantly to better management practices as the shale gas industry expands worldwide.


Asunto(s)
Industria Procesadora y de Extracción/métodos , Agua Subterránea/química , Gas Natural/efectos adversos , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Cromatografía de Gases y Espectrometría de Masas , Fenómenos Geológicos , Pennsylvania
13.
Med Tr Prom Ekol ; (2): 29-34, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-25895249

RESUMEN

Performed in 2013, sampling of centralized and noncentralized water-supply and analysis of engineering technology materials on household water use in 6 cities of Murmansk region (Nikel, Zapolyarny, Olenegorsk, Montchegorsk, Apatity, Kirovsk), subjected to industrial emissions, enabled to evaluate and compare levels of 15 metals in water sources (lakes and springs) and the cities' drinkable waters. Findings are that some cities lack sanitary protection zones for water sources, most cities require preliminary water processing, water desinfection involves only chlorination. Concentrations of most metals in water samples from all the cities at the points of water intake, water preparation and water supply are within the hygienic norms. But values significantly (2-5 times) exceeding MACs (both in water sources and in drinkable waters of the cities) were seen for aluminium in Kirovsk city and for nickel in Zapolarny and Nikel cities. To decrease effects of aluminium, nickel and their compounds in the three cities' residents (and preserve health of the population and offsprings), the authors necessitate specification and adaptation of measures to purify the drinkable waters from the pollutants. In all the cities studied, significantly increased concentrations of iron and other metals were seen during water transportation from the source to the city supply--that necessitates replacement of depreciated water supply systems by modern ones. Water taken from Petchenga region springs demonstrated relatively low levels of metals, except from strontium and barium.


Asunto(s)
Agua Potable/análisis , Metales/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Agua Potable/química , Humanos , Industrias , Metales/química , Federación de Rusia , Agua/análisis , Agua/química , Contaminantes Químicos del Agua/química
14.
Toxicol Appl Pharmacol ; 284(3): 330-8, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25759245

RESUMEN

Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50 to 1000 µg/L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p<0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17ß-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic's possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females.


Asunto(s)
Intoxicación por Arsénico/genética , Arsenicales/efectos adversos , Disruptores Endocrinos/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Abastecimiento de Agua/análisis , 17-Hidroxiesteroide Deshidrogenasas/genética , Adulto , Bangladesh , Receptor alfa de Estrógeno/genética , Femenino , Perfilación de la Expresión Génica/métodos , Marcadores Genéticos , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores Sexuales
15.
Sci Total Environ ; 518-519: 280-9, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25770450

RESUMEN

Disinfection by-products (DBPs) constitute a large family of compounds. Trihalomethanes and haloacetic acids are regulated in various countries, but most DBPs are not. Monitoring DBPs can be delicate, especially for small systems, because various factors influence their formation and speciation. Short-term variations of DBPs can be important and particularly difficult for small systems to handle because they require robust treatment and operation processes. According to our knowledge, for the first time, our study covers the short-term variability of regulated and non-regulated DBP occurrence in small systems in the summer. An intensive sampling program was carried out in six small systems in Canada. Systems in the provinces of Newfoundland and Labrador and Quebec were sampled daily at the water treatment plant and at six different locations along the distribution system. Five DBP families were studied: trihalomethanes, haloacetic acids, haloacetonitriles, halonitromethanes and haloketones. Results show that there were considerable variations in DBP levels from week to week during the month of study and even from day to day within the week. On a daily basis, DBP levels can fluctuate by 22% to 96%. Likewise, the large number of sampling locations served to observe DBP variations along the distribution system. Observations revealed some degradation and decomposition of non-regulated DBPs never before studied in small systems that are associated with the difficulty these systems experience in maintaining adequate levels of residual disinfectant. Finally, this study reveals that the short term temporal variability of DBPs is also influenced by spatial location along the distribution system. In the short term, DBP levels can fluctuate by 23% at the beginning of the system, compared to 40% at the end. Thus, spatial and temporal variations of DBPs in the short term may make it difficult to select representative locations and periods for DBP monitoring purposes in small systems.


Asunto(s)
Desinfectantes/análisis , Agua Potable/química , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Terranova y Labrador , Quebec , Análisis Espacio-Temporal , Trihalometanos/análisis , Purificación del Agua/métodos , Abastecimiento de Agua/análisis , Abastecimiento de Agua/estadística & datos numéricos
16.
Artículo en Inglés | MEDLINE | ID: mdl-25734827

RESUMEN

Reports of ground water contamination in a southwestern Pennsylvania community coincided with unconventional shale gas extraction activities that started late 2009. Residents participated in a survey and well water samples were collected and analyzed. Available pre-drill and post-drill water test results and legacy operations (e.g., gas and oil wells, coal mining) were reviewed. Fifty-six of the 143 respondents indicated changes in water quality or quantity while 63 respondents reported no issues. Color change (brown, black, or orange) was the most common (27 households). Well type, when known, was rotary or cable tool, and depths ranged from 19 to 274 m. Chloride, sulfate, nitrate, sodium, calcium, magnesium, iron, manganese and strontium were commonly found, with 25 households exceeding the secondary maximum contaminate level (SMCL) for manganese. Methane was detected in 14 of the 18 houses tested. The 26 wells tested for total coliforms (2 positives) and E. coli (1 positive) indicated that septic contamination was not a factor. Repeated sampling of two wells in close proximity (204 m) but drawing from different depths (32 m and 54 m), revealed temporal variability. Since 2009, 65 horizontal wells were drilled within a 4 km (2.5 mile) radius of the community, each well was stimulated on average with 3.5 million gal of fluids and 3.2 million lbs of proppant. PA DEP cited violations included an improperly plugged well and at least one failed well casing. This study underscores the need for thorough analyses of data, documentation of legacy activity, pre-drill testing, and long term monitoring.


Asunto(s)
Industria Procesadora y de Extracción , Gas Natural , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/análisis , Pozos de Agua/análisis , Región de los Apalaches , Escherichia coli , Industria Procesadora y de Extracción/ética , Industria Procesadora y de Extracción/métodos , Agua Subterránea/análisis , Humanos , Metano/análisis , Gas Natural/provisión & distribución , Yacimiento de Petróleo y Gas , Pennsylvania , Población Rural , Aguas Residuales/química , Aguas Residuales/toxicidad , Calidad del Agua , Abastecimiento de Agua/análisis , Pozos de Agua/química
18.
AAPS J ; 17(3): 558-85, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25739816

RESUMEN

In Canada, as many as 20 pharmaceutically active compounds (PhACs) have been detected in samples of treated drinking water. The presence of these PhACs in drinking water raises important questions as to the human health risk posed by their potential appearance in drinking water supplies and the extent to which they indicate that other PhACs are present but have not been detected using current analytical methods. Therefore, the goal of the current investigation was to conduct a screening-level assessment of the human health risks posed by the aquatic release of an evaluation set of 335 selected PhACs. Predicted and measured concentrations were used to estimate the exposure of Canadians to each PhAC in the evaluation set. Risk evaluations based on measurements could only be performed for 17 PhACs and, of these, all were found to pose a negligible risk to human health when considered individually. The same approach to risk evaluation, but based on predicted rather than measured environmental concentrations, suggested that 322 PhACs of the evaluation set, when considered individually, are expected to pose a negligible risk to human health due to their potential presence in drinking waters. However, the following 14 PhACs should be prioritized for further study: triiodothyronine, thyroxine, ramipril and its metabolite ramiprilat, candesartan, lisinopril, atorvastatin, lorazepam, fentanyl, atenolol, metformin, enalaprilat, morphine, and irbesartan. Finally, the currently available monitoring data for PhACs in Canadian surface and drinking waters was found to be lacking, irrespective of whether their suitability was assessed based on risk posed, predicted exposure concentrations, or potency.


Asunto(s)
Agua Potable/análisis , Preparaciones Farmacéuticas/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Canadá , Agua Potable/normas , Monitoreo del Ambiente/métodos , Humanos , Preparaciones Farmacéuticas/química , Medición de Riesgo , Abastecimiento de Agua/normas
19.
Environ Monit Assess ; 187(4): 164, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25740689

RESUMEN

This study proposes to introduce the remote sensing and geographic information system (GIS) techniques in mapping the groundwater potential zones. Remote sensing and GIS techniques have been used to map the groundwater potential zones in Salem Chalk Hills, Tamil Nadu, India. Charnockites and fissile hornblende biotite gneiss are the major rock types in this region. Dunites and peridodites are the ultramafic rocks which cut across the foliation planes of the gneisses and are highly weathered. It comprises magnesite and chromite deposits which are excavated by five mining companies by adopting bench mining. The thickness of weathered and fracture zone varies from 2.2 to 50 m in gneissic formation and 5.8 to 55 m in charnockite. At the contacts of gneiss and charnockite, the thickness ranges from 9.0 to 90.8 m favoring good groundwater potential. The mine lease area is underlined by fractured and sheared hornblende biotite gneiss where groundwater potential is good. Water catchment tanks in this area of 5 km radius are small to moderate in size and are only seasonal. They remain dry during summer seasons. As perennial water resources are remote, the domestic and agricultural activities in this region depend mainly upon the groundwater resources. The mines are located in gently slope area, and accumulation of water is not observed except in mine pits even during the monsoon period. Therefore, it is essential to map the groundwater potential zones for proper management of the aquifer system. Satellite imageries were also used to extract lineaments, hydrogeomorphic landforms, drainage patterns, and land use, which are the major controlling factors for the occurrence of groundwater. Various thematic layers pertaining to groundwater existence such as geology, geomorphology, land use/land cover, lineament, lineament density, drainage, drainage density, slope, and soil were generated using GIS tools. By integrating all the above thematic layers based on the ranks and weightages, eventually groundwater potential zones were demarcated. The study indicates that groundwater potential is good to high in 22 villages and moderate in 13 villages. The good to high potential zone occupies an area of 128 km2 and moderate potential zone occupies an area of 77 km2. Groundwater occurrence is poor in five villages which need artificial recharge to augment groundwater.


Asunto(s)
Monitoreo del Ambiente/métodos , Sistemas de Información Geográfica , Agua Subterránea/química , Recursos Hídricos/análisis , Carbonato de Calcio , Geología , India , Minería , Estaciones del Año , Abastecimiento de Agua/análisis
20.
Sci Total Environ ; 518-519: 168-88, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25747376

RESUMEN

The Pampean plain is the most productive region in Argentina. The Pampeano Aquifer beneath the Pampean plain is used mostly for drinking water. The study area is the sector of the Pampeano Aquifer underlying the Del Azul Creek basin, in Buenos Aires province. The main objective is to characterize the chemical and isotopic compositions of groundwater and their origin on a regional scale. The methodology used involved the identification and characterization of potential sources of solutes, the study of rain water and groundwater chemical and isotopic characteristics to deduce processes, the development of a hydrogeochemical conceptual model, and its validation by hydrogeochemical modelling with PHREEQC. Groundwater samples come mostly from a two-depth monitoring network of the "Dr. Eduardo J. Usunoff" Large Plains Hydrology Institute (IHLLA). Groundwater salinity increases from SW to NE, where groundwater is saline. In the upper basin groundwater is of the HCO3-Ca type, in the middle basin it is HCO3-Na, and in the lower basin it is ClSO4-NaCa and Cl-Na. The main processes incorporating solutes to groundwater during recharge in the upper basin are rain water evaporation, dissolution of CO2, calcite, dolomite, silica, and anorthite; cationic exchange with Na release and Ca and Mg uptake, and clay precipitation. The main processes modifying groundwater chemistry along horizontal flow at 30 m depth from the upper to the lower basin are cationic exchange, dissolution of silica and anorthite, and clay precipitation. The origin of salinity in the middle and lower basin is secular evaporation in a naturally endorheic area. In the upper and middle basins there is agricultural pollution. In the lower basin the main pollution source is human liquid and solid wastes. Vertical infiltration through the boreholes annular space during the yearly flooding stages is probably the pollution mechanism of the samples at 30 m depth.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea/análisis , Abastecimiento de Agua/análisis , Argentina , Agua Subterránea/química , Hidrología , Contaminantes Químicos del Agua , Abastecimiento de Agua/estadística & datos numéricos
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