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3.
Sci Rep ; 12(1): 4641, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388035

RESUMO

Dense data acquisition for 3-D high-resolution aquifer mapping through heliborne transient electromagnetic (HTEM) survey is continually not possible due to various technical and administrative constraints. Consequently, we apply ground geophysical surveys at possibly closer spacing to collect the sub-surface information in the no-fly area, which provides only a regional aquifer picture. In the area near Patna of Northern India, an extent of 18% was covered under the HTEM survey, and the rest was surveyed by ground geophysical methods. Both data are integrated using the theory of regionalized variables. The parameters of multi-aquifers i.e., top of the first aquifer, top of the separating clay layer, top and the bottom of second aquifer, are estimated together with their respective resistivities. The estimations are made at an interval of 250 m, practically an appropriate distance at which dense data generation was carried out using the HTEM survey. The integrated approach generates the data in the no-fly area with the same spatial density as the flown area. With this, we achieved the goal of completing the 3-D aquifer mapping of the entire area with dense data at high spatial resolution. This is a unique finding to manage the handicapped situation in this HTEM surveys, and an aide to overcome such constraints with cost-effectiveness.

4.
Sci Rep ; 12(1): 6191, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418610

RESUMO

Assessment of morphodynamic groundwater reserves is important for the sustainable management of water resources. It is a truth that groundwater resource evaluation is anxious with the ambiguity of its several factors and employing methods. Thus, an information-based model has been hypothesized to assess natural groundwater reserves in a morphodynamic system in a part of the Ganga basin of Northern India, where the spatial variability in natural groundwater reserve exists. Marginal information of rainfall data, and transinformation among the rainfall, and monthly depth to groundwater level measurement at 50 wells in a dense monitoring network were used for evaluating natural groundwater reserve. The results indicate that an average recharge rate is about 246 mm/monsoon and or 32.65% of the seasonal rainfall, and its values are well-correlated with the soil infiltration rate. It has been found that the estimated recharge rates are about 54.08, 45.85, 33.77, 32.48, and 32.14% of the seasonal rainfall in an active flood plain, back swamp, natural levees, flood plain, and palaeochannel, respectively. The calculated annual rainfall input to groundwater reserve is found about 127.98 MCM/monsoon rainfall, which could be employed for sustainable management of groundwater resources in the morphodynamic system of the Ganga river basin.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Monitoramento Ambiental/métodos , Inundações , Índia , Rios , Poços de Água
5.
Adv Exp Med Biol ; 1306: 121-127, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33959910

RESUMO

Analysis of fluoride in body fluids (urine and serum) is essential for fluorosis diagnosis. Although 24-h urine collection is adopted to assess community defluoridation/fluoride supplementation program/research studies, but not feasible for Clinical/Pathological laboratories. Patients are reluctant to bring 24-h urine samples. Hence, spot urine samples are collected in clean, dry polypropylene bottles (not glass) without any preservative and analyzed on the same day by the Ion analyzer (ISE method). Equal volumes of Total Ionic Strength Adjustment Buffer (TISAB) solution are then added with body fluids before analysis and mixed well to eliminate interference from other ions besides pH adjustment and to provide a constant ionic strength. Results are reported as mg of Fluoride/l (ppm). High fluoride level in body fluids is an indication of confirmed cases of fluorosis. Two interventions, e.g. withdrawal of fluoride intake and intake of nutritive diet was introduced for prevention and control of fluorosis. The present study is to provide useful guidelines for monitoring of fluorosis disease in human beings, those who are at the risk of fluoride exposure.


Assuntos
Líquidos Corporais , Fluorose Dentária , Fluoretos , Fluorose Dentária/diagnóstico , Humanos , Eletrodos Seletivos de Íons , Concentração Osmolar
6.
Sci Rep ; 11(1): 9279, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33927257

RESUMO

An increased nitrate (NO3-) concentration in groundwater has been a rising issue on a global scale in recent years. Different consumption mechanisms clearly illustrate the adverse effects on human health. The goal of this present study is to assess the natural and anthropogenic NO3- concentrations in groundwater in a semi arid area of Rajasthan and its related risks to human health in the different groups of ages such as children, males, and females. We have found that most of the samples (n = 90) were influenced by anthropogenic activities. The background level of NO3- had been estimated as 7.2 mg/L using a probabilistic approach. About 93% of nitrate samples exceeded the background limit, while 28% of the samples were beyond the permissible limit of 45 mg/L as per the BIS limits. The results show that the oral exposure of nitrate was very high as compare to dermal contact. With regard to the non-carcinogenic health risk, the total Hazard Index (HITotal) values of groundwater nitrate were an average of 0.895 for males, 1.058 for females, and 1.214 for children. The nitrate health risk assessment shows that about 38%, 46%, and 49% of the samples constitute the non-carcinogenic health risk to males, females, and children, respectively. Children were found to be more prone to health risks due to the potential exposure to groundwater nitrate.


Assuntos
Testes Diagnósticos de Rotina/métodos , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Nitratos/análise , Medição de Risco/métodos , Poluentes Químicos da Água/análise , Idoso , Criança , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade
7.
Chemosphere ; 265: 129096, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33280841

RESUMO

Arsenic contaminated groundwater is seen as one of the most critical routes of human exposure to geogenic pollutants. Recently around 40 million inhabitants of the world are living in the hazardous zone having groundwater As level >50 µg/L. As problem of groundwater in Bhagirathi-Ganga deltaic plain is well-known for over the last three decades. Hydrogeochemical analytical data related to the As concentration had been analysed to identify the As sources in groundwater of the active floodplains of the Ganga basin in Northern India. The natural background level of As was also estimated using Grubb's test and cumulative probability plots. The natural background level is a crucial parameter for identifying and quantifying groundwater pollution and assessing measures to control pollution. The anthropogenic addition of As in groundwater was separated by the estimated inflection point. The results show that the highest As concentration, which is 8-times more than the permissible limit, is observed at Gyantoli village in Begusarai district in Bihar state. Groundwater is alkaline with a high concentration of HCO3- as compared to other chemical parameters. Further, it indicates the dominance of carbonate weathering and relatively high pH values (range: 8.00-9.00) helps to release As in groundwater. The reducing environment of the aquifer system becomes oxic at the shallow depth due to comparatively shallow groundwater level, and impressive water level fluctuation resulting in vertical mixing of anthropogenic As contaminants.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Monitoramento Ambiental , Humanos , Índia , Rios , Poluentes Químicos da Água/análise
8.
Environ Pollut ; 266(Pt 3): 115150, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32755763

RESUMO

Natural background levels (NBLs) and threshold values (TVs) are crucial parameters for identification and the quantification of groundwater pollution, and the evaluation of pollution control measures. The cumulative probability distribution technique was used for the evaluation of NBLs for 36 samples collected during two climate conditions in the part of the desert area from Rajasthan, India. The NBLs for Na+, Cl-, SO42-, HCO3-, NO3- and F- ions were assessed and compared with the natural and anthropogenic processes. The TVs were also calculated for Na+, Cl-, SO42-, HCO3-, NO3- and F- ions, and compared with the drinking limits of the Bureau of Indian Standards. Additionally, the pollution percentage (%) at the individual well was estimated and identified the polluted zones. Results indicate that most of the polluted areas were situated in the southern part, which was influenced by the natural and anthropogenic factors. The sodium concentrations above the TVs, in indicating the saline nature of water. Chloride threshold value above the drinking water limit was mainly observed in the dry season, related to intensive evaporation and industrial waste, which leads to groundwater quality degradation. The NO3- concentration (∼56% samples) above the TVs indicates extensive use of nitrate fertilizers and sewage effluent. The values of total dissolved solids (TDS) shows the suspicious scenario as about 84% of the samples in the dry period and about 89% in the wet season exceeding the drinking limit. Assessment of background concentrations and threshold values on regional and local scale assigns the basis for the identification of groundwater pollution, and helpful for better water quality guidelines to protecting of water resources.


Assuntos
Água Subterrânea , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Índia , Qualidade da Água
9.
Homo ; 66(5): 455-70, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26142831

RESUMO

Variations in finger and palmar dermatoglyphic patterns are investigated among the Limboo (18-60 years, 150 males and 150 females), a little known population of Sikkim. The results for Limboo were compared with other North-East Indian populations. The most commonly occurring pattern was loop (males: 64.33%; females: 75.00%) followed by whorl (males: 31.00%; females: 21.33%) and finally arch (males: 4.67%; females: 3.66%). There were no significant differences between sexes in pattern types. The overall values of pattern intensity (P.I.I.), Dankmeijer's (D.I.) and Furuhata's (F.I.) indices were 14.08, 12.60 and 96.06 respectively. The P.I.I. was within the range for East Asian populations of North-East India. The D.I. was similar to those reported for Rajbanshi, Kalita, Rabha and Newar populations, while F.I. was higher than in other populations of Eastern Himalaya and North-East India. The most frequently occurring mainline formulae in all palm prints (left and right combined) were 7.5'.5.- followed by 9.7.5.- and finally 11.9.7.- (p>0.05) and these were similar to the reported values for other North-eastern populations of India. The mean values of total finger ridge count (TFRC) and absolute finger ridge count (AFRC) were greater among males (138.03; s=42.26 and 198.78; s=77.4) than females (137.91; s=44.15 and 194.47; s=86.71). The a-b ridge count was greater among females than males. Sex differences in AFRC and a-b ridge count were both statistically significant (p<0.05). The mean TFRC values were within ranges for populations of North-East India. Cluster analysis based on P.I.I., D.I. and F.I. shows affinity of the Limbo to some of the populations of Assam and North-East India.


Assuntos
Dermatoglifia , Adolescente , Adulto , Dermatoglifia/classificação , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Siquim , Adulto Jovem
10.
Lett Appl Microbiol ; 58(2): 184-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24118020

RESUMO

UNLABELLED: Assessment of antibacterial as well as antiherpes virus activity of sulfonoquinovosyldiacylglyceride (SQDG), a glycolipid, isolated from the leaves of Azadirachta indica has been described. Antimicrobial activity was evaluated against Gram-positive, Gram-negative bacteria and herpes simplex virus. SQDG showed significant inhibitory activity against Salmonella typhi and two isolates of Shigella dysenteriae with MIC values 32 µg ml(-1) , while three isolates of Salm. typhi, Escherichia coli and Vibrio cholerae were inhibited at 64 µg ml(-1) and have shown zone diameter ranging from 6.2 to 12.3 mm. The growth kinetics study of SQDG on Salm. typhi and Sh. dysenteriae revealed that the growths were completely inhibited at their MIC values within 24 h of exposure. Interestingly, SQDG inhibits herpes simplex virus (HSV) type 1 and 2 with the EC50 of 9.1 and 8.5 µg ml(-1) , compared with acyclovir (2.2 and 2.8 µg ml(-1) against HSV-1 and HSV-2). The selectivity index (SI) was found to be 12.4 against HSV-1 and 13.41 with HSV-2. Furthermore, the expression of proinflammatory cytokines of HSV-infected and SQDG-treated macrophages using ELISA kit revealed that SQDG significantly downregulated the production of TNF-α, IL-1ß, IL-12 and IL-6. SIGNIFICANCE AND IMPACT OF THE STUDY: The water-soluble metabolite sulfonoquinovosyldiacylglyceride (SQDG) isolated from Azadirachta indica (Neem) possess significant antibacterial as well as anti-HSV activity. The efficacies as well as the solubility factor of SQDG substantiate a greater attention for its use as phytotherapeutic drug for controlling microbial infections as most consumers have better acceptance of phytomedicines than synthetic drugs.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Azadirachta/química , Glicolipídeos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Simplexvirus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Citocinas/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Glicolipídeos/química , Glicolipídeos/isolamento & purificação , Bactérias Gram-Negativas/crescimento & desenvolvimento , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/crescimento & desenvolvimento , Ensaio de Placa Viral
11.
J Assoc Physicians India ; 62(7): 572-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25672028

RESUMO

OBJECTIVES: The objective of this communication is to disseminate scientific and technical information for early diagnosis of Fluorosis; recent developments in care and management of patients of Fluorosis. MATERIAL AND METHODS: Body fluids collected from patients suspected of Fluorosis referred by hospitals, samples of drinking water used by them are the materials that have been investigated. Fluoride level in body fluids and water samples are tested by the ion selective electrode (ISE) potentiometry. Forearm X-ray radiograph is taken to assess interosseous membrane calcification. Upon diagnosis of the disease, two corrective measures, namely diet editing and diet counselling are introduced for practice in daily life. In the former, all sources of fluoride ingestion and use are withdrawn whereas in the latter, the patient is encouraged to consume a diet rich in essential nutrients, antioxidants and micronutrients through fruits, vegetables and dairy products. The patients are monitored at intervals to assess fluoride in body fluids. Reduction in fluoride levels has a direct relationship with disappearance of health complaints and subsequent recovery. RESULTS: Eight case studies (5 male + 3 female) are described. Patients'complaints are gastrointestinal discomfort, polyuria, polydipsia, muscle weakness, fatigue and joint pain. Body fluids may have high fluoride with normal or high fluoride level in drinking water.The main source(s) of fluoride entry identified are (i) consuming fluoride contaminated food/snacks/beverages laced with black rock salt; (ii) drinking of untreated ground water; (iii) using fluoridated toothpaste. The duration of recovery varies from patient to patient depending upon their body physiology and the seriousness with which the interventions were practiced. Recurrence of the disease may occur in some patients due to change in life-style, not practicing interventions, entry of fluoride inadvertently. CONCLUSION: This communication provides an overview of Fluorosis, its occurrence, manifestations, diagnostic tests, results, interventions practiced, monitoring and recovery from the disease.


Assuntos
Doenças Ósseas/induzido quimicamente , Países em Desenvolvimento , Diagnóstico Precoce , Fluoretos/efeitos adversos , Fluorose Dentária/diagnóstico , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/diagnóstico , Adulto , Doenças Ósseas/diagnóstico , Doenças Ósseas/dietoterapia , Diagnóstico Diferencial , Comportamento Alimentar , Feminino , Fluoretos/administração & dosagem , Fluorose Dentária/dietoterapia , Gastroenteropatias/dietoterapia , Humanos , Índia , Masculino , Pessoa de Meia-Idade
12.
Int J Occup Environ Med ; 4(2): 61-72, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23567531

RESUMO

BACKGROUND: Fluoride is used increasingly in a variety of industries in India. Emission of fluoride dust and fumes from the smelters of primary aluminum producing industries is dissipated in the work environment and poses occupational health hazards. OBJECTIVE: To study the prevalence of health complaints and its association with fluoride level in body fluids of smelter workers in a primary aluminum producing industry. METHODS: In an aluminum industry, health status of 462 smelter workers, 60 supervisors working in the smelter unit, 62 non-smelter workers (control group 1) and 30 administration staff (control group 2) were assessed between 2007 and 2009. Their health complaints were recorded and categorized into 4 groups: 1) gastro-intestinal complaints; 2) non-skeletal manifestations; 3) skeletal symptoms; and (4) respiratory problems. Fluoride level in body fluids, nails, and drinking water was tested by an ion selective electrode; hemoglobin level was tested using HemoCue. RESULTS: The total complaints reported by study groups were significantly higher than the control groups. Smelter workers had a significantly (p<0.001) higher urinary and serum fluoride level than non-smelter workers; the nail fluoride content was also higher in smelter workers than non-smelter workers (p<0.001). The smelter workers with higher hemoglobin level had a significantly (p<0.001) lower urinary fluoride concentration and complained less frequently of health problems. Only 1.4% of the smelter workers were consuming water with high fluoride concentrations. A high percentage of participants was using substances with high fluoride contents. CONCLUSION: Industrial emission of fluoride is not the only important sources of fluoride exposure--consumption of substance with high levels of fluoride is another important route of entry of fluoride into the body. Measurement of hemoglobin provides a reliable indicator for monitoring the health status of employees at risk of fluorosis.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Alumínio , Fluoretos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Adulto , Poluentes Ocupacionais do Ar/análise , Estudos de Casos e Controles , Fluoretos/análise , Nível de Saúde , Humanos , Índia/epidemiologia , Metalurgia , Pessoa de Meia-Idade , Unhas/química , Prevalência
13.
J Environ Biol ; 34(6): 1059-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24555337

RESUMO

The present study explores the potentiality of sugarcane charcoal for fluoride removal from synthetic fluoride solution. Column adsorption experiments with respect to variation of flow rate, pH, initial concentration, and column depths were carried out. Sugarcane charcoal exhibited almost consistent scavenging capacity at various bed depths with a flow rate 4.34 ml min(-1). Maximum adsorption capacity of sugarcane charcoal was recorded 7.33 mg g(-1). The adsorption studies were simulated using Thomas and Bed depth service time model. Both the models consistently predict its characteristic parameters and describe the breakthrough profiles in the whole range of sorption process.


Assuntos
Carvão Vegetal/química , Fluoretos/isolamento & purificação , Saccharum/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Modelos Químicos
14.
J Environ Biol ; 34(5): 963-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24558813

RESUMO

The objective of the present study was to access the pollutant generated from bio-fuels like bamboo sticks, cow dung, paddy straw, carbon dust cake, gobar gas, jute stick, and mustard stick and synthetic fuel like LPG during cooking in rural villages of Burdwan, West Bengal, India and its fluctuation in living room. The average SO2 released from the fuels was found in the following order: bamboo stick > cow dung > paddy straw > carbon cake > gobar gas > jute stick > LPG > mustard stick; NO2 emission was in the following order : mustard stick > carbon dust cake > paddy straw > cow dung cake > LPG, jute stick > gobar gas > bamboo stick > and SPM was obtained in the following sequence: cow dung cake > bamboo stick > carbon dust cake > gobar gas > LPG > mustard stick > paddy straw > jute stick, respectively. The highest living room to kitchen room (L/K) ratio of SO2, NO, and SPM was found in LPG, gobar gas, jute stick respectively in 2009 and followed by bamboo stick > paddy straw > jute stick > cow dung cake, respectively in 2010. Results of this study suggest that different fuels released different amount of air pollutants, but more extensive study is needed to confirm the relationship between fuels and released air pollutants.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental , Dióxido de Nitrogênio/análise , Material Particulado/análise , Dióxido de Enxofre/análise , Biocombustíveis , Culinária , Monitoramento Ambiental , Índia
15.
Environ Monit Assess ; 185(6): 4869-86, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23054274

RESUMO

A geophysical survey was conducted over an industrial belt encompassing 80 functional leather factories in Southern India. These factories discharge untreated effluents which pollute shallow groundwater where electrical conductivity (EC) value had a wide range between 545 and 26,600 µS/cm (mean, 3, 901 µS/cm). The ranges of Na(+) and Cl(-) ions were from 46 to 4,850 mg/L (mean, 348 mg/L) and 25 to 10,390 mg/L (mean, 1,079 mg/L), respectively. Geoelectrical layer parameters of 37 vertical electrical soundings were analyzed to demarcate fresh and saline water zones. However, the analysis not did lead to a unique resolution of saline and fresh waters. It was difficult to assign a definitive value to the aquifer resistivity of any area. Thus, geophysical indicators, namely longitudinal unit conductance (S), transverse unit resistance (T), and average longitudinal resistivity (Rs), were calculated for identifying fresh and saline waters. Spatial distributions of S, T, and R s reflected widely varying ranges for the saline and fresh water zones. Further, the empirical relation of formation factor (F) was established from pore-water resistivity and aquifer resistivity for fresh and saline aquifers, which may be used to estimate local EC values from the aquifer resistivity, where well water is not available.


Assuntos
Fenômenos Geológicos , Água Subterrânea/química , Salinidade , Cloreto de Sódio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Índia
16.
Environ Monit Assess ; 184(8): 5121-38, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21927785

RESUMO

This paper deals with a systematic hydrogeological, geophysical, and hydrochemical investigations carried out in SIPCOT area in Southern India to demarcate groundwater pollution and saline intrusion through Uppanar River, which flows parallel to sea coast with high salinity (average TDS 28, 870 mg/l) due to back waters as well as discharge of industrial and domestic effluents. Hydrogeological and geophysical investigations comprising topographic survey, self-potential, multi-electrode resistivity imaging, and water quality monitoring were found the extent of saline water intrusion in the south and pockets of subsurface pollution in the north of the study area. Since the area is beset with highly permeable unconfined quaternary alluvium forming potential aquifer at shallow depth, long-term excessive pumping and influence of the River have led to lowering of the water table and degradation of water quality through increased salinity there by generating reversal of hydraulic gradient in the south. The improper management of industrial wastes and left over chemicals by closed industries has led surface and subsurface pollution in the north of the study area.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Poluentes Químicos da Água/análise , Índia , Salinidade , Poluição Química da Água/estatística & dados numéricos
17.
Environ Monit Assess ; 184(5): 2857-79, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21713490

RESUMO

Groundwater in a tannery belt in Southern India is being polluted by the discharge of untreated effluents from 80 operating tanneries. Total dissolved solids and chloride (Cl(-)) measurements in open wells in the tannery cluster vary from 27,686 to 39,100 and 12,000 to 13,652 mg/l, respectively. A mass transport model was constructed using Visual MODFLOW Premium 4.4 software to investigate the chloride migration in an area of 75.56 km(2). Input to the chloride migration model was a groundwater flow model that considered steady and transient conditions. This model was calibrated with field observations; and sensitivity analysis was carried out whereby model parameters, viz., conductivity, dispersivity, and source concentration were altered slightly, and the effect on calibration statistics was evaluated. Results indicated that hydraulic conductivity played a more sensitive role than did dispersivity. The Cl(-) migration was mainly through advection rather than dispersion. It was found that even if the pollutant load reduced to 50% of the present level, the Cl(-) concentration in groundwater, even after 6 years, would not be reduced to the permissible limit of drinking water in the tannery belt.


Assuntos
Cloretos/análise , Água Subterrânea/química , Curtume/estatística & dados numéricos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Índia , Cinética , Modelos Químicos , Movimentos da Água , Poluição Química da Água/estatística & dados numéricos
18.
Environ Monit Assess ; 177(1-4): 315-35, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20711862

RESUMO

The impact of seawater intrusion was investigated using major hydrogeochemical ions to evaluate the origin of salinity in Sadras watershed located between Buckingham Canal and Bay of Bengal in the southeastern coast of India. From empirical data collected twice during pre- and post-monsoon seasons, it was found that groundwater was slightly acidic to mildly alkaline, and more than 44% of groundwater samples had EC > 3,000 µS/cm in both the seasons. Results of principle component analysis (PCA) showed that Na( + ), Cl( - ), Mg(2 + ), and SO[Formula: see text] concentrations had the highest loading factor and the samples affected by saline/seawater were separated from the cluster. Hydrochemical processes that accompany the saline/seawater were identified using ionic changes. It was observed during sampling periods that the mixing due to saline/seawater intrusion varied from 4.82-7.86%. Negative values of ionic change (e (change)) for Na( + ) and K( + ) decreased with the increasing fraction of seawater. Furthermore, salinity, sodium adsorption ratio, percentage of sodium Na (%), and exchangeable sodium percentage in well samples showed that groundwater was unsuitable for irrigation purposes.


Assuntos
Ânions/análise , Cátions/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Ânions/química , Cátions/química , Monitoramento Ambiental , Água Doce/química , Fenômenos Geológicos , Concentração de Íons de Hidrogênio , Índia , Análise de Componente Principal , Salinidade , Sódio/análise , Sódio/química , Poluentes Químicos da Água/química
19.
Environ Monit Assess ; 163(1-4): 215-27, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19267209

RESUMO

There is a growing concern over the potential accumulation of trace element concentration in groundwater of coastal aquifer owing seawater encroachment in the last several decades. A total of 29 groundwater samples collected from Pesarlanka Island, Krishna delta, Andhra Pradesh, India were analyzed for 13 trace elements (B, V, Mn, Fe, Ni, Co, Cu, Zn, As, Sr, Cd, Ba, and Pb) using inductively coupled plasma mass spectrometry. The results reveal that B, Fe, Ni, As, Sr, and Pb vary from 11.22 to 710.2, 1.25 to 684.6, 0.02 to 37.33, 27.8 to 282.3, 164.1 to 7,009, and 1.97 to 164.4 microg/l, respectively. Ba, Cd, Co, Cu, Ni, V, and Zn are almost within permissible limits for drinking water, but As, Fe, Mn, Pb, B, and Sr are above the permissible limit. The toxic element Pb is 1.64 times more than the maximum permissible limits of drinking water. The minimum value of As is also 2.78 times more, whereas the maximum is 28.2 times the permissible limit. The spatial distributions of alkaline earths (Sr, Ba), transition metals (V, Co, Ni, Fe), metallic elements (Cu, Pb), and (As) were found in considerable variation in the entire Island. Good cross-correlations were found between As, B, Co, and Sr with total dissolved solids and among other trace elements such as B, As, Co, and Sr. The variability observed within the groundwater samples is closely connected to the sea spray input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and time of year. The trace element levels, in particular those of heavy metals, are very low, suggesting an origin from natural sources rather than from anthropogenic contamination. A few trace elements (Sr and B) are found as sensitive parameters responding to changes in fresh to saline groundwater environment. The highly elevated trace elements in this area which may be attributed to marine sediments or death and decay of plants are presented in this paper.


Assuntos
Oligoelementos/análise , Poluentes Químicos da Água/análise , Índia
20.
Environ Monit Assess ; 158(1-4): 145-54, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18839323

RESUMO

Lakshadweep is a group of 36 coral islands scattered in the Arabian Sea off the western coast of India. On such small tiny islands, groundwater is the only source of fresh water for the islanders. Due to the growing population on these islands, demand for fresh water is also increasing and on the other side the peculiar hydrologic, geologic and geomorphic features restrict the availability of groundwater. Therefore, a proper understanding of the groundwater condition is important in order to meet this increasing demand and also to formulate future development and management strategies. Detailed hydrogeological, geophysical and hydrochemical studies have been carried out to identify potential fresh groundwater resources and quantify vulnerable parts of Andrott Island, Union Territory of Lakshadweep. Systematic collection and analysis of hydrological, geophysical and hydrochemical data reveal that fresh groundwater is only available between 2.5 to 5.0 m depths and provide an early sign of deterioration in groundwater quality in the peripheral parts of eastern and western coasts of this island. It suggests immediate measures for arresting the deterioration in groundwater quality as well as augmentation for restoration of aquifer in some parts of the island.


Assuntos
Monitoramento Ambiental , Água Doce/análise , Geografia , Índia , Água do Mar/análise , Movimentos da Água
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