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1.
Environ Res ; 214(Pt 2): 113958, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35921904

RESUMO

Brackish lake systems and estuaries are unique aquatic systems that support diversified life forms and strongly influence a region's economy. Major chemical water quality parameters of India's second-largest brackish water lake, Pulicat were assessed. Physico-chemical parameters like pH, temperature, suspended solid concentrates, total dissolved solids, salinity, nitrogenous nutrients, phosphate, silicate, and chlorophyll a were analysed. The results obtained for different parameters were compared and interpreted with statistical software SPSS version 20 and images were plotted using the Arc GIS spatial analyst tool. During the summer months, the nitrogen to phosphorus ratio ranges from a minimum of 1.96 to a maximum of 16.64 (9.55 ± 4.01) while it ranges from a minimum of 7.98 to a maximum of 15.52 (12.47 ± 2) during the pre-monsoon. In the monsoon season, the nitrogen to phosphorus ratio of surface water suggests a range from a minimum of 8.64 to a maximum of 17.58 (13.87 ± 2.14). During the post-monsoon season, the nitrogen to phosphorus ratio ranges from 4.98 to 17.34 (11.77 ± 3.68). The average nitrogen to phosphorus ratios were 9.6, 12.5, 13.9 and 11.8 in summer, pre-monsoon, monsoon, and post-monsoon respectively. The nitrogen to phosphorus ratio was lower than the Redfield ratio for all the seasons. The average concentration of chlorophyll a was 14.9, 13.4, 12.8 and 11.8 in summer, pre-monsoon, monsoon, and post-monsoon respectively. As per the Pearson Correlation Coefficient, there was no significant correlation among nitrogen, phosphorus, and chlorophyll a. This suggests the influence of suspended solid concentrates, and nitrogen and phosphorus flux in the sediment-water interface might be interfering with the nutrient cycles and primary productivity.


Assuntos
Lagos , Poluentes Químicos da Água , Ásia , Clorofila A/análise , Monitoramento Ambiental , Lagos/análise , Nitrogênio/análise , Fósforo/análise , Águas Salinas , Estações do Ano , Poluentes Químicos da Água/análise
2.
Mar Pollut Bull ; 171: 112728, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34303058

RESUMO

The presence of microplastics in all ecological and environmental conditions has been identified as a global problem. This article aimed to study edible salt-associated microplastics from the major salt-producing states of India. The crystal and powder salt from Tamil Nadu and Gujarat (five samples of powder salt and three samples of crystal salt from each state) were collected and analyzed for their microplastic content. The total microplastic content in the salts ranged from 46 to 115 particles per 200 g in Gujarat salt and 23 to 101 particles per 200 g in Tamil Nadu salt. The microplastics are dominated by red and blue color fibrous-shaped materials. The most common microplastics identified in the edible salts were polyethylene, polyester, and polyvinyl chloride derived from marine and salt-processing units.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Índia , Plásticos , Poluentes Químicos da Água/análise
3.
Mar Pollut Bull ; 137: 610-616, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30503475

RESUMO

This is the first study on the distribution and characteristics of plastic debris found in the sediments of Rameswaram Island, Gulf of Mannar, India. Studies on the distribution of plastics and microplastic content in highly populated coral islands and their impact on the coral ecosystem are very scarce. For this purpose, marine sediment samples were collected from 20 locations along the coastal areas of the study region. The distribution and characterization study was carried out by visual examination followed by FTIR spectroscopy. The results showed abundance of white-colored and irregular-shaped plastic debris in this study area. Polypropylene was identified as a dominant polymer variety, followed by polyethylene, polystyrene, nylon, and polyvinyl chloride. Tourist activities and fishing practices were found to be the possible sources of the microplastic debris. Additionally, the distribution of the plastics was found to be dominantly controlled by the aeolian process and the nature of the coast.


Assuntos
Sedimentos Geológicos/análise , Plásticos/análise , Poluentes Químicos da Água/análise , Praias , Recifes de Corais , Ecossistema , Índia , Ilhas , Nylons/análise , Polietileno/análise , Polipropilenos/análise , Poliestirenos/análise , Cloreto de Polivinila/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduos/análise
4.
Mar Pollut Bull ; 133: 107-116, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30041297

RESUMO

Eighty-three surface sediments were collected to investigate the element concentration based sediment pollution and potential ecological risk status of the Pulicat lagoon, southeast coast of India. The textural characteristics, Fe and Mn concentration in the surface sediments are chiefly controlled by the confluence of riverine inputs and vicinity of the marine environment. The varied distribution of CaCO3 concentration is due to the depth of the lagoon followed by the sand and silty sand characteristics of the substratum. The surface sediments are derived from riverine sources. Sediment Pollution Index (SPI), Potential Ecological Risk Index of the sediments suggests that they are falling under less polluted and low potential ecological risk category.


Assuntos
Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Carbonato de Cálcio/análise , Monitoramento Ambiental , Índia , Medição de Risco , Poluição Química da Água/análise
5.
Indian J Tuberc ; 65(3): 260-261, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29933871

RESUMO

A 50-year-old woman presented with pain, swelling, and reduced range of motion of right knee joint since one year. Radiograph of knee joint revealed eccentric, expansile, geographic lytic lesion on the medial epiphyseal region of tibia mimicking giant cell tumor (GCT). She underwent minimally invasive biopsy, which was positive for acid-fast bacilli and revealed necrotizing chronic granulomatous lesion, diagnostic of tuberculosis (TB). This case emphasizes to consider tuberculosis arthritis as differential diagnosis when a case of destructive giant cell tumor is encountered.


Assuntos
Articulação do Joelho , Tuberculose Osteoarticular/diagnóstico , Antituberculosos/uso terapêutico , Diagnóstico Diferencial , Feminino , Tumores de Células Gigantes/diagnóstico , Humanos , Pessoa de Meia-Idade , Dor/etiologia , Tuberculose Osteoarticular/complicações , Tuberculose Osteoarticular/diagnóstico por imagem , Tuberculose Osteoarticular/tratamento farmacológico
6.
Data Brief ; 18: 180-189, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29896509

RESUMO

From koppunuru study area totally 58 samples were collected in 7 different boreholes, minimum depth of 28 m and Maximum depth of 157.7 m. The borehole samples geochemical analysis (major and trace elements) was carried out at Atomic Minerals Directorate for Exploration & Research (AMD), Hyderabad, India. Major and trace element studies have been conducted on the Neoproterozoic Palnad sub-basin Andhra Pradesh, South India, to determine their Geochemistry, Uranium mineralization and provenance characteristics. Geochemically, this sedimentary basin has a different litho - unit like as gritty quartzite, conglomerate, and Shale. This study area mainly dominated by Uranium deposited and radioactive elements are predominately deposit. Strong positive correlation between Uranium and Lead (r = 0.887) suggested radiogenic nature of this system.

7.
Mar Pollut Bull ; 131(Pt A): 547-551, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29886981

RESUMO

Nine sampling stations were fixed to carry out the preliminary investigation on coastal debris from Nallathanni island, Gulf of Mannar Biosphere Reserve, Southeast coast of India. The coastal debris were separated and identified using hand picking, visual identification and microscopic studies. The coastal areas of the study region were less dominated by micro plastic contamination. The coastal debris was dominated by polyethylene bottles and fibrous fishnet materials. The distribution of the coastal debris along the coastal region is chiefly controlled by winnowing action of sea waves and Aeolian action along the berm region.


Assuntos
Resíduos/análise , Poluentes da Água/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Índia , Ilhas , Plásticos/análise , Polietileno/análise , Poluentes Químicos da Água/análise
8.
Mar Pollut Bull ; 62(11): 2537-42, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21924748

RESUMO

A survey on the Partially Extracted Trace Metals (PETMs) concentration (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd) in beach sediments is reported for the first time from 57 different locations in Chennai Metropolitan City of Southeast coast of India. The concentration of PETMs suggests that they are mainly concentrated with organic matter in the crowded part of the industrial regions in the beaches from the northern part rather than the tourist beaches in the southern part of the city. The comparison on enrichment of trace metals indicates higher values of Pb, Ni in the beaches than lowest effect level (LEL) and effects range low (ERL) than the tourist beaches.


Assuntos
Praias , Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Sedimentos Geológicos/análise , Metais Pesados/análise , Coleta de Dados , Monitoramento Ambiental/métodos , Índia
9.
Mar Pollut Bull ; 62(4): 845-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21414640

RESUMO

A survey on the metal concentrations (As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, Zn) in beach water and sediments is reported from the tourist destination of Acapulco city on the Pacific coast of Mexico. The concentration of dissolved trace metals (DTMs) in beach water and acid leachable trace metals (ALTMs) in sediments indicated that they are anthropogenic in nature due to the increased tourist activities in the crowded beach locations. The statistical analysis indicates Fe and Mn play a major role as metal scavengers in both the medium (water and sediment) and the higher value of other metals is site specific in the study area, indicating that they are transported from the local area. Comparison results suggest that the beach water quality has deteriorated more than the sediments and special care needs to be taken to restore the beach quality.


Assuntos
Praias/estatística & dados numéricos , Sedimentos Geológicos/química , Metais/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , México , Poluição Química da Água/estatística & dados numéricos
10.
Environ Monit Assess ; 170(1-4): 609-29, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20052614

RESUMO

The article presents the results for enrichment of total trace metals (TTMs) from Pallikaranai salt marsh in South Chennai, a metropolis on the southeast coast of India. TTMs Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, Sr, V, and Hg along with sediment texture, OC, and CaCO3 were analyzed in 36 surface sediments collected during August 2008 to recognize and observe the input of TTMs in the marsh from various sources in the city limits. In view of the rapid urbanization and industrialization in Chennai City, especially on the southern side, uncontrolled input of sewage, garbage, and industrial effluents into the Pallikaranai marsh land, the elevated concentrations are not surprising. The level of enrichment of TTMs has also increased by 20% to 60% for most of the elements when compared with all other ecosystems in the world as well as the nearby area. The results also indicate that the marshy region is more heavily contaminated with Cd, Hg, Cr, Cu, Ni, Pb, and Zn than other regions on the southeast coast of India. The Enrichment Factor, Contamination Factor, and I (geo) indexes are calculated, and these values are useful to assess the degree of pollution in sediments. The spatial distributions of TTMs are also controlled by other factors like geochemical, precipitation, and flocculation of particulate substances in the marsh. The results of the present study suggest the need for a regular monitoring and management program which will help to improve the quality of Pallikaranai pristine marsh land.


Assuntos
Água Doce/química , Metais/análise , Urbanização , Poluentes Químicos da Água/análise , Áreas Alagadas , Monitoramento Ambiental , Sedimentos Geológicos/química , Índia
11.
Singapore Med J ; 50(8): e287-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19710961

RESUMO

Spondylolisthesis associated with neurofibromatosis is rare, and only 12 cases have been reported so far. However, only one report of grade 4 spondylolisthesis with neurofibromatosis has been reported in the literature. A 15-year-old boy with neurofibromatosis was admitted for back pain and neurological claudication. Radiograph showed grade 4 spondylolisthesis of the L5 vertebra with scalloping of the L4-L5 vertebrae. L4-L5 laminectomy, reduction, L3-S1 posterior instrumentation and fusion were performed. The reduction of the spondylisthesis was done entirely from the posterior approach using pedicle screws. Radiography at four months showed a broken S1 screw with a loss of reduction. The patient was re-operated on, to provide additional stability with pelvic fixation. He was pain-free with a good fusion at the two-year follow-up. Adequate posterior stabilisation with fusion gives good results in grade 4 spondylolisthesis associated with neurofibromatosis and dural ectasia.


Assuntos
Neurofibromatoses/complicações , Neurofibromatoses/diagnóstico , Espondilolistese/complicações , Espondilolistese/diagnóstico , Adolescente , Dor nas Costas , Parafusos Ósseos , Dilatação Patológica/diagnóstico , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/cirurgia , Humanos , Fixadores Internos , Vértebras Lombares/diagnóstico por imagem , Masculino , Neurofibromatoses/diagnóstico por imagem , Neurofibromatoses/cirurgia , Radiografia , Escoliose/diagnóstico , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Espondilolistese/diagnóstico por imagem , Espondilolistese/cirurgia
12.
Spine (Phila Pa 1976) ; 34(11): 1167-75, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19444065

RESUMO

STUDY DESIGN: It is a retrospective study of 52 neuromuscular scoliosis patients with cerebral palsy (CP). OBJECTIVE: To determine the effectiveness and amount of correction using posterior-only pedicle screw construct. SUMMARY OF BACKGROUND DATA: Although there have been many reports in literature supporting the use of pedicle screw-only constructs for the correction of adolescent idiopathic scoliosis, similar studies have not been reported in patients with CP. METHODS: We retrospectively evaluated outcomes of 52 neuropathic scoliosis patients (28 males and 24 females) with CP over minimum 2 years of follow-up. All patients underwent pedicle screw fixation without any anterior procedure for the correction. Pelvic fixation was done in 10 patients who had pelvis obliquity more than 15 degrees . All coronal and sagittal parameters were noted after surgery and at final follow-up. Patient's functional outcome was measured using modified Rancho Los Amigos Hospital system criteria. Complications were recorded from record sheets and any change in the ambulatory status was also recorded. RESULTS: Mean age was 22 years at the time of operation and average follow-up was 36.1 month. Cobb's angle was improved to 62.9% (P < 0.0001) from 76.8 degrees to 30.1 degrees after surgery and 31.5 degrees at final follow-up. This correction of scoliosis (41% approximately 92%) was found to be statistically significant (P < 0.0001). Overall correction in pelvic obliquity was 56.2% from 9.2 degrees before surgery to 4.0 degrees after surgery which was 43.1% at final follow-up to 5.2 degrees. Twenty-one patients (42%) improved their functional ability by grade 1 with 2 patients by grade 2. After the operation parent or caretakers of patients exhibited better sitting balance and nursing care. There were 32% complications in the series major being pulmonary. There were 2 perioperative deaths and 1 patient developed neurologic deficit due to screw impingement in canal, which was resolved after removal. CONCLUSION: We reported satisfactory coronal and sagittal correction with posterior-only pedicle screw fixation without higher complication rate in CP patients. Further long-term study is recommended to evaluate the success of pedicle screw in this population.


Assuntos
Parafusos Ósseos , Paralisia Cerebral/complicações , Escoliose/cirurgia , Fusão Vertebral/métodos , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Cifose/fisiopatologia , Cifose/cirurgia , Masculino , Avaliação de Resultados em Cuidados de Saúde , Radiografia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Escoliose/complicações , Escoliose/fisiopatologia , Fusão Vertebral/instrumentação , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/fisiopatologia , Vértebras Torácicas/cirurgia , Fatores de Tempo , Adulto Jovem
13.
Eur Spine J ; 18(1): 52-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19037669

RESUMO

It is a measurement of Cobb's angles between adolescent (AIS) and juvenile (JIS) idiopathic scoliosis who had stable curves (variation <5 degrees) in more than three visits. Main objective of this paper is to measure inter- and intra-observer reliability of measurements between AIS and JIS who had stable curves in regular follow-up. Twenty-nine JIS and 44 AIS patients who had stable curves without bracing were identified using PACS system. Two observers independently measured Cobb's angle twice on first, during follow-up and final radiogram using computer-based digital radiogram. Both observers were given pre-decided level of upper and lower end plates. Inter- and intra-observer reliability of the measurement was calculated using Pearson correlation-coefficient test between JIS and AIS group. There was no significant difference in Cobb's angle in all measurements by both observers either in JIS (p = 0.756, range 0.706-0.815; ANOVA) or AIS (p = 0.871, range 0.795-0.929; ANOVA) group which suggested that there is no significant difference in Cobb's angle in repeated measurements. Intra-observer reliability for JIS (r = 0.600, range 0.521-0.751; Pearson test) was less than AIS (r = 0.969, range 0.943-0.984; Pearson test); and similarly, inter-observer reliability for JIS (r = 0.547, Pearson test) was also less than AIS (r = 0.961, Pearson test) which indicates that Cobb's angle measurement is less reliable in patients who have juvenile idiopathic scoliosis. Using the identical condition for measurements in both the groups, we could find only one reason for less reliability in JIS group and that is poor demarcation of the vertebral end-plates in this group. This poor inter- and intra-observer reliability in JIS due to ill-defined endplates can be reduced by measuring all previous curves along with latest curves at the same time during the follow-up of patients with JIS to decide about the progression of curves and treatment options.


Assuntos
Variações Dependentes do Observador , Escoliose/diagnóstico por imagem , Escoliose/epidemiologia , Adolescente , Criança , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Radiografia
14.
Arch Orthop Trauma Surg ; 129(4): 425-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18600335

RESUMO

Congenital short femur is a rare and complex deformity that is often associated with other anomalies. There are few reports of either hip or knee dislocations during femoral lengthening in congenital short femur predisposed by associated anomaly. However, there are probably no case reports of both hip and knee joint dislocation occurring in same case during femoral lengthening in congenital short femur. We have this case of congenital short femur, where both hip and knee dislocation occurs during femoral lengthening. We reviewed different article to understand the cause and avoid such unwanted complications in future.


Assuntos
Fêmur/anormalidades , Fêmur/cirurgia , Luxação do Quadril/etiologia , Técnica de Ilizarov/efeitos adversos , Luxação do Joelho/etiologia , Criança , Comorbidade , Feminino , Luxação do Quadril/diagnóstico por imagem , Luxação do Quadril/epidemiologia , Humanos , Luxação do Joelho/diagnóstico por imagem , Luxação do Joelho/epidemiologia , Desigualdade de Membros Inferiores/etiologia , Psoríase/epidemiologia , Radiografia
15.
Asian Spine J ; 2(2): 74-80, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20404960

RESUMO

STUDY DESIGN: A retrospective study. PURPOSE: To compare outcomes of apical derotation with pedicle screws in idiopathic and neuromuscular scoliosis (NMS). OVERVIEW OF LITERATURE: No information about apical derotation in NMS with pedicle screws is available. METHODS: We performed deformity correcting surgery using pedicle screw constructs on 12 adolescent idiopathic scoliosis (AIS) patients (mean age 14.1 years) and 16 NMS patients (mean age 16.5 years). Preoperative, postoperative, and final follow-up radiographs were analyzed for Cobb's angle and pelvic obliquity, while apical rotation was measured on CT scans using the Aaro-Dahlborn method. RESULTS: For AIS, the mean preoperative Cobb's angle, pelvic obliquity, and apical rotation values were 57.3 degrees , 2.8 degrees , and 20.4 degrees , respectively, and postoperatively they were 16.8 degrees , 1.1 degrees and 14.7 degrees , respectively, showing significant correction. For NMS, the mean preoperative Cobb's angle, pelvic obliquity, and apical rotation values were 75.6 degrees , 13.7 degrees , and 42.9 degrees , respectively, and postoperatively they were 27.1 degrees , 5.8 degrees , and 34.1 degrees , respectively, also showing significant correction. There were no significant differences between AIS and NMS patients Cobb's angle p=0.306, pelvic obliquity p=0.887 and apical derotation p=0.113 degrees . There were no differences in curve severity in the three groups (AIS, NMS >80 degrees and NMS <80 degrees ); or the correction of apical rotation (p=0.25), although less correction was achieved in the Cobb's angle in the >80 NMS group (p=0.04). CONCLUSIONS: Apical axial derotation can be achieved with posterior only pedicle screw fixation in NMS without anterior release, with comparable results in idiopathic scoliosis.

16.
Asian Spine J ; 2(2): 90-3, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20404962

RESUMO

STUDY DESIGN: We evaluated computer assisted digital measurement of radiographic parameters in patients with idiopathic scoliosis. PURPOSE: To assess the reliability of digital measurements. OVERVIEW OF LITERATURE: Various authors analyzed scoliotic deformities by conventional radiographs, but very few studies have addressed the reliability of digital radiographic measurement using computer software. METHODS: Three independent, blinded observers measured 318 whole spine pre-operative antero-posterior radiograms of children with varying degrees of idiopathic scoliosis. Only one curve per radiograph was measured. Each observer measured the Cobb angle three times with a 1-week gap between each measurement. The computer system, picture archiving and communication system (PACS, PiViewSTAR version 5) was used in all cases. The end vertebrae were pre-selected to avoid this as a potential source of error. The results were statistically analyzed for intraobserver and interobserver reliability and variability. RESULTS: The 95% confidence intervals for intraobserver and interobserver variability were +/-1.30 and +/-1.260, respectively. There was better reliability in larger curves. CONCLUSIONS: Measurement using a digitized system may help to minimize measurement discrepancies by eliminating an intrinsic cause of error.

17.
Asian Spine J ; 2(1): 38-43, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20411141

RESUMO

STUDY DESIGN: Retrospective comparative study using radiographs and clinical findings. PURPOSE: To test the hypothesis that asymmetric loading of immature spines in young athletes initiates scoliosis. OVERVIEW OF LITERATURE: Scoliosis in athletes has been reported in the literature, but its causative factors have not been investigated. METHODS: We compared the incidence, type and magnitude of scoliotic curves in volleyball players with those in the non-player population. One hundred sixteen adolescent volleyball players were grouped for selective screening. Data regarding their playing duration, handedness, age, height, and menarchal status (in girls) were recorded, along with clinical examination and radiological investigation when necessary. We analyzed data from 46,428 non-player school children, and their data were compared to athletes to determine differences. RESULTS: Volleyball players had a statistically significant increase in the incidence of scoliotic spinal curves. Playing hand dominance was related to the curve direction. Cobb angle had no significant correlation with the duration of playing. CONCLUSIONS: There is a five-fold increase in the incidence of mild scoliosis in volleyball players. A high percentage (41%) of asymmetry was present on the Adams forward bending test, as compared to controls. The curves were either thoracic or thoracolumbar.

18.
Methods Find Exp Clin Pharmacol ; 29(2): 93-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17440625

RESUMO

High concentration of fluorine is noxious to the health of humans and animals. Analysis of fluoride in water samples meant for human consumption in the Vellore District of Tamil Nadu, India, revealed its presence above the permissible limit (4.56 ppm). The present study was aimed to investigate the toxic effects of oral administration of the water sample that contains the highest fluoride content on the status of pathophysiological parameters and lipid peroxidation in experimental rats. A positive control group orally treated with 4.5 ppm of fluoride was also included in the study. The assay of pathophysiological enzymes and histological observations made on the stomach and intestinal tissue have revealed the toxic effects of fluoride intoxication. The observed increase in the levels of thiobarbituric acid reactive substances (TBARS) both in plasma and in intestinal epithelium, with a concomitant decrease in both enzymatic and nonenzymatic antioxidants in the plasma of experimental rats, revealed that the altered antioxidant status during fluoride intoxication may be due to increased free radical generation.


Assuntos
Antioxidantes/metabolismo , Fluoretos/toxicidade , Mucosa Intestinal/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Animais , Ânions , Cátions , Exposição Ambiental , Intoxicação por Flúor , Fluoretos/administração & dosagem , Radicais Livres/metabolismo , Humanos , Índia , Masculino , Ratos , Ratos Wistar , Poluentes Químicos da Água
19.
Environ Pollut ; 145(1): 245-57, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16698156

RESUMO

Core sediments from Mullipallam Creek of Muthupet mangroves on the southeast coast of India were analyzed for texture, CaCO(3), organic carbon, sulfur and acid leachable trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn and Cd). Textural analysis reveals a predominance of mud while CaCO(3) indicates dissolution in the upper half of the core, and reprecipitation of carbonates in reduction zones. Trace metals are diagenetically modified and anthropogenic processes control Pb and, to some extent, Ni, Zn and Fe. A distinct event is identified at 90 cm suggesting a change in deposition. Strong relationship of trace metals with Fe indicates that they are associated with Fe-oxyhydroxides. The role of carbonates in absorbing trace metals is evident from their positive relationship with trace metals. Comparison of acid leachable trace metals indicates increase in concentrations in the study area and the sediments act as a sink for trace metals contributed from multiple sources.


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos , Metais Pesados/análise , Ácidos/química , Cádmio/análise , Carbonato de Cálcio/análise , Carbono/análise , Carbonatos/química , Cromo/análise , Cobalto/análise , Cobre/análise , Monitoramento Ambiental/métodos , Índia , Ferro/análise , Chumbo/análise , Manganês/análise , Níquel/análise , Sulfatos/análise , Zinco/análise
20.
Environ Monit Assess ; 132(1-3): 263-74, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17180415

RESUMO

The Lower Ponnaiyar River Basin forms an important groundwater province in South India constituted by Tertiary formations dominated by sandstones and overlain by alluvium. The region enjoyed artesian conditions 50 years back but at present frequent failure of monsoon and over exploitation is threatening the aquifer. Further, extensive agricultural and industrial activities and urbanization has resulted in the increase in demand and contamination of the aquifer. To identify the sources and quality of groundwater, water samples from 47 bore wells were collected in an area of 154 km2 and were analysed for major ions and trace metals. The results reveal that the groundwater in many places is contaminated by higher concentrations of NO3, Cl, PO4 and Fe. Four major hydrochemical facies Ca-Mg-Cl, Na-Cl, Ca-HCO3 and Na-HCO3 were identified using Piper trilinear diagram. Salinity, sodium adsorption ratio, and sodium percentage indicate that most of the groundwater samples are not suitable for irrigation as well as for domestic purposes and far from drinking water standards. The most serious pollution threat to groundwater is from nitrate ions, which are associated with sewage and fertilizers application. The present state of the quality of the lower part of Ponnaiyar River Basin is of great concern and the higher concentration of toxic metals (Fe and Ni) may entail various health hazards.


Assuntos
Rios/química , Poluição da Água/análise , Água/normas , Substâncias Perigosas/análise , Índia , Íons/análise , Metais Pesados/análise , Nitratos/análise , Sais/análise , Sódio/análise , Abastecimento de Água/análise , Abastecimento de Água/normas
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