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1.
Environ Monit Assess ; 186(5): 3001-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24497080

RESUMEN

Polybrominated diphenyl ethers (PBDEs) used extensively over the past 3 decades as flame retardants in most types of polymers, all over the world, have been identified as global pollutants. PBDEs pose various health problems such as thyroid hormone disruption, permanent learning and memory impairment, behavioral changes, hearing deficits, delayed puberty onset, fetal malformations, and possibly cancer. Many measurements of PBDEs in various matrices from Sweden, Holland, Japan, the USA, and elsewhere have been reported, but few measurements are available for India. In this study, a preliminary screening of different congeners of PBDEs has been performed in different old electronic and consumer products with an objective to build capacity in order to analyze PBDEs and BFRs. Six different samples, foam from upholstery, motherboard of a computer, children toy composite sample, old vanishing window blind sample, electrical wire sample, and PVC flooring sample, were collected and analyzed for the presence of the following PBDE congeners: BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, and BDE-209. It was found that three out of six samples were positive for the presence of PBDEs. Three congeners were detected in the samples, i.e., BDE-47, BDE-153, and BDE-209, of which, highest concentration was of BDE-209. Among the samples, motherboard of computer showed the highest concentration of BDE-209 followed by window blind and foam from upholstery. The results of this preliminary investigation indicate that PBDEs are still present in the old consumer products which can be an important additional source of exposure to the population.


Asunto(s)
Monitoreo del Ambiente , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , Sustancias Peligrosas/análisis , Materiales Manufacturados/análisis , India , Juego e Implementos de Juego , Bifenilos Polibrominados/análisis
2.
Bull World Health Organ ; 91(8): 553-561J, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23940402

RESUMEN

OBJECTIVE: To rank pollutants in two Nigerian water supply schemes according to their effect on human health using a risk-based approach. METHODS: Hazardous pollutants in drinking-water in the study area were identified from a literature search and selected pollutants were monitored from April 2010 to December 2011 in catchments, treatment works and consumer taps. The disease burden due to each pollutant was estimated in disability-adjusted life years (DALYs) using data on the pollutant's concentration, exposure to the pollutant, the severity of its health effects and the consumer population. FINDINGS: The pollutants identified were microbial organisms, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc. All were detected in the catchments but only cadmium, cobalt, chromium, manganese and lead exceeded World Health Organization (WHO) guideline values after water treatment. Post-treatment contamination was observed. The estimated disease burden was greatest for chromium in both schemes, followed in decreasing order by cadmium, lead, manganese and cobalt. The total disease burden of all pollutants in the two schemes was 46 000 and 9500 DALYs per year or 0.14 and 0.088 DALYs per person per year, respectively, much higher than the WHO reference level of 1 × 10(-6) DALYs per person per year. For each metal, the disease burden exceeded the reference level and was comparable with that due to microbial contamination reported elsewhere in Africa. CONCLUSION: The estimated disease burden of metal contamination of two Nigerian water supply systems was high. It could best be reduced by protection of water catchment and pretreatment by electrocoagulation.


Asunto(s)
Agua Potable/química , Contaminantes del Agua/aislamiento & purificación , Abastecimiento de Agua/análisis , Costo de Enfermedad , Personas con Discapacidad , Humanos , Nigeria , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Medición de Riesgo/métodos , Purificación del Agua/normas
3.
Environ Monit Assess ; 184(11): 6627-35, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22131013

RESUMEN

Bacteria play a significant role in water contamination. Chemicals are mostly used for the treatment of bacteriologically contaminated water. The use of bacterial interactions is a new approach to limit the pathogens' growth. Detection of antimicrobial substances produced by lactic acid bacteria against the waterborne pathogens is the objective of this work. Microbiological and biochemical methods were used to identify lactic acid bacteria having an antimicrobial activity. Evaluation of antimicrobial activity with growth kinetic measurements was performed. Four isolates of lactic acid bacteria obtained from whey and curd were identified. The predominant species belonging to the Lactobacillus genera are: Lactobacillus rhamnosus, Lactobacillus sakei, Lactobacillus paracasei, and Lactobacillus paraplantarum. The present study revealed that the Lactobacillus consortium is able to inhibit Staphylococcus aureus's growth along with Escherichia coli and Vibrio species. In mixed culture, after 24 h, the Lactobacillus consortium reduces the growth of S. aureus by 2.03 log; moreover, the growth of the latter bacteria totally ceased after 72 h of incubation. The protein produced by the Lactobacillus consortium was responsible for arresting the growth of S. aureus.


Asunto(s)
Bacterias/crecimiento & desarrollo , Agentes de Control Biológico , Lactobacillus/fisiología , Microbiología del Agua , Antibacterianos/metabolismo , Antibacterianos/toxicidad , Bacteriocinas/metabolismo , Bacteriocinas/toxicidad , Escherichia coli/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/crecimiento & desarrollo
4.
Environ Monit Assess ; 184(4): 2487-96, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21671013

RESUMEN

Heavy metals released from different sources in urban environment get adsorbed on respirable particulate matter less than 10 µm in size (PM(10)) and are important from public health point of view causing morbidity and mortality. Therefore, the ambient air quality monitoring was carried out to study the temporal and special pattern in the distribution of PM(10) and associated heavy metal content in the atmosphere of Nagpur, Maharashtra State, India during 2001 as well as in 2006. PM(10) fraction was observed to exceed the stipulated standards in both years. It was also observed that minimum range of PM(10) was observed to be increased in 2006 indicating increase in human activity during nighttime also. Six heavy metals were analyzed and were observed to occur in the order Zn > Fe > Pb > Ni > Cd > Cr in 2006, similar to the trend in other metro cities in India. Lead and Nickel were observed to be within the stipulated standards. Poor correlation coefficient (R(2)) between lead and PM(10) indicated that automobile exhaust is not the source of metals to air pollution. Commercial and industrial activity as well as geological composition may be the potential sources of heavy metal pollution. Total load of heavy metals was found to be increased in 2006 with prominent increase in zinc, lead, and nickel in the environment. Public health impacts of heavy metals as well as certain preventive measures to mitigate the impact of heavy metals on public health are also summarized.


Asunto(s)
Contaminantes Atmosféricos/análisis , Ciudades , Metales Pesados/análisis , Monitoreo del Ambiente , India
5.
Environ Monit Assess ; 179(1-4): 619-25, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21063769

RESUMEN

The present investigation reports the results of a monitoring study focusing on groundwater quality of Bhandara District of central India. Since, remediation of groundwater is very difficult, knowledge of the existing nature, magnitude, and sources of the various pollution loads is a prerequisite to assessing groundwater quality. The water quality index (WQI) value as a function of various physicochemical and bacteriological parameters was determined for groundwater obtained from a total of 21 locations. The WQI during pre-monsoon season varied from 68 to 83, while for post-monsoon, it was between 56 and 76. Significantly (P < 0.01) lower WQI for the post-monsoon season was observed, indicating deterioration of the groundwater overall in corresponding season. The study revealed that groundwater from only 19% locations was fit for domestic use, thus indicating the need of proper treatment before use.


Asunto(s)
Agua Dulce/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , India , Estaciones del Año , Contaminación Química del Agua/estadística & datos numéricos
6.
Bioresour Technol ; 99(7): 2552-8, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17566726

RESUMEN

Anaerobic acclimatization of activated sludge from a textile effluent treatment plant to high concentration of RB5 could effectively decolorize RB5 dye solution. The strains viz. Pseudomonas aeruginosa and Bacillus circulans and other unidentified laboratory isolates (NAD1 and NAD6) were predominantly present in the microbial consortium. The conditions for efficient decolorization, biostimulation to increase effectiveness of microbial consortium, its tolerance to high salt concentration and non-specific ability towards decolorization of eight azo dyes, are reported. The optimum inoculums concentration for maximum decolorization were found to be 1-5 ml of 1800+/-50 mg l(-1) MLSS and 37 degrees C, respectively. The decolorization efficiency was 70-90% during 48 h. The biomass showed efficient decolorization even in the presence of 10% NaCl, as tested with RB5. In the presence of flavin adenine dinucleotide (FAD) more than 99% decolorization occurred in 8h. The decolorization of RB5 was traced to extracellular enzymes. The effectiveness of acclimatized biomass under optimized conditions towards decolorization of two types of synthetic dye bath wastewaters that were prepared using chosen azo dyes is reported.


Asunto(s)
Compuestos Azo/metabolismo , Bacillus/metabolismo , Color , Colorantes/metabolismo , Pseudomonas aeruginosa/metabolismo , Espectrofotometría Ultravioleta
7.
J Environ Biol ; 28(4): 851-6, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18405124

RESUMEN

Increased risk of ill-health and diseases has been associated with employment in the ferro-alloy factory. Since measurement of transition metals in human blood and hair along with respective exposure rates, provides a means of assessing individual risk, it has been the most important part of the study. In the study majority of the elements in the transition series, such as, vanadium (V), chromium (Cr), iron (Fe), manganese (Mn), cobalt, (Co) nickel (Ni), copper (Cu), zinc (Zn), molybdenum (Mo) and cadmium (Cd) were considered which are randomly emitted from the source, that is, manganese ore (used during ferro-alloy manufacturing process). The commonly available transition, metals, observed in biological samples of ferro-alloy workers, were found to be Fe, Zn, Co, Ni, Cu, Cr, Cd, V Mn and Mo in blood, while in hair, Mn, Fe, Zn, Co, Ni, Cu, Cr, Cd, V and Mo were present in decreasing order Surveillance of bio-concentration of these metals in workers, exposed to close proximity of the coke-ovens and smelting furnaces, revealed that the workers were prone to several physical disorders.


Asunto(s)
Exposición Profesional , Elementos de Transición/análisis , Cabello/química , Humanos , Elementos de Transición/sangre
8.
Artículo en Inglés | MEDLINE | ID: mdl-25745563

RESUMEN

Garden biomass (GB) is defined as low density and heterogeneous waste fraction of garden rubbish like grass clippings, pruning, flowers, branches, weeds; roots. GB is generally different from other types of biomass. GB is mostly generated through maintenance of green areas. GB can be processed for bio energy production as it contains considerably good amount of cellulose and hemicellulose. However, pretreatment is necessary to delignify and facilitate disruption of cellulosic moiety. The aim of the present investigation was to pretreat GB using Fenton's reagent and to study the influence of Fe(2+) and H2O2 concentrations on degradation of lignin and cellulose. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14 to optimize different process variables such as temperature, concentration of Fe(2+) and H2O2. The results of the present investigation showed that Fenton's reagent was effective on GB, however, concentration of Fe(2+) and H2O2 play crucial role in determining the efficiency of pretreatment. An increase in H2O2 concentration in Fenton's reagent significantly increased the rate of cellulose and lignin degradation in contrast to increasing concentration of Fe(2+) ion which led to a decrease in lignocellulosic degradation.

9.
Waste Manag ; 40: 92-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25816769

RESUMEN

A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment.


Asunto(s)
Álcalis/química , Biomasa , Lignina/química , Energía Solar , Agricultura , Celulasa , Celulosa/química , Restauración y Remediación Ambiental , Hidrólisis , India , Microscopía Electrónica de Rastreo , Polisacáridos/química , Eliminación de Residuos , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Luz Solar , Temperatura , Difracción de Rayos X
10.
Water Res ; 49: 186-96, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24333520

RESUMEN

Recent evidence shows that water distribution system (WDS) is a major risk factor in piped water supply system and the degree of contamination of water in WDS is usually influenced by seasonal variation. Risk assessment studies eliminate the effect of seasonality whenever annualized estimate of concentration of contaminants in water is used to determine the risk to health. In tropical climate where strong seasonal variation prevails, the excess risk during dry and hot season, above the annualized risk can be significant. This study investigates what impact seasonal adjustment may have on health improvement targets for WDS. Water quality data of two Nigerian water supply schemes were used to estimate the impact of WDS on water quality. Seasonal deviation from the annualized impact was quantified as the latent risk in disability-adjusted life years (DALYs). The hazards identified in both WDSs were cadmium and lead, and the estimated 95th-percentile risk of the metals, over the course of dry season was about 31-38%, and 1-3% higher than the estimated yearly average risk, respectively. Wilcoxon signed-rank test showed that the risk distributions during the dry season was significantly higher (p < 0.05) than the yearly average. The median latent risks (5th, 95th-percentiles), for both WDS were 0.014 (7.6 × 10(-3), 0.023) and 4.8 × 10(-3) (-, 7.6 × 10(-3)) DALYs/person/year for cadmium and 0.87 × 10(-3) (0, 0.1 × 10(-3)) and 0.16 × 10(-3) (0, 0.031 × 10(-3)) DALYs/person/year, respectively, for lead. These risks are substantially higher than the WHO limit (1 × 10(-6) DALYs/person/year). Therefore, to achieve effective health improvement target, mitigation measures should be planned and executed by season.


Asunto(s)
Costo de Enfermedad , Estaciones del Año , Clima Tropical , Calidad del Agua , Abastecimiento de Agua , Modelos Teóricos , Nigeria , Contaminantes Químicos del Agua/análisis
11.
Bioresour Technol ; 114: 382-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22444633

RESUMEN

The effect of various additives such as fly ash, phosphogypsum, jaggery, lime, and polyethylene glycol on green waste composting was investigated through assessing their influence on microbial growth, enzymatic activities, organic matter degradation, bulk density, quality of finished compost including gradation test, heavy metal analysis, etc. A perusal of results showed that addition of jaggery and polyethylene glycol were helpful to facilitate composting process as they significantly influenced the growth of microbes and cellulase activity. The quality of finished compost prepared from jaggery and polyethylene glycol added treatments were superior to other composts, wherein reduction in C/N ratio was more than 8% in jaggery treatment. All other parameters of compost quality including gradation test also favored jaggery and polyethylene glycol as the best additives for green waste composting.


Asunto(s)
Tecnología Química Verde/métodos , Compuestos Orgánicos/química , Compuestos Orgánicos/metabolismo , Eliminación de Residuos/métodos , Microbiología del Suelo , Suelo/química
12.
Water Res ; 44(3): 681-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19822345

RESUMEN

A molecularly imprinted polymer (MIP) adsorbent for carcinogenic polycyclic aromatic hydrocarbons (PAHs) was prepared using a non-covalent templating technique. MIP particles sized from 2 to 5 microm were synthesized in acetonitrile by using six PAHs mix as a template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. When compared with the non-imprinted polymer (NIP), the MIP showed an excellent affinity towards PAHs in aqueous solution with binding capacity (B(max)) of 687 microg g(-1)MIP, imprinting effect of 6, and a dissociation constant of 24 microM. The MIP exhibited significant binding affinity towards PAHs even in the presence of environmental parameters such as dissolved organic matter (COD) and total dissolved inorganic solids (TDS), suggesting that this material may be appropriate for removal of carcinogenic PAHs. The feasibility of removing PAHs from water by the MIP demonstrated using groundwater spiked with PAHs. In addition, the MIP reusability without any deterioration in performance was demonstrated at least ten repeated cycles.


Asunto(s)
Carcinógenos/aislamiento & purificación , Impresión Molecular/métodos , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Polímeros/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Conservación de los Recursos Naturales , Ambiente , Humanos , Microscopía Electrónica de Rastreo , Impresión Molecular/economía , Suelo/análisis , Propiedades de Superficie , Temperatura , Factores de Tiempo , Abastecimiento de Agua/análisis
13.
Environ Sci Technol ; 43(8): 2871-7, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19475964

RESUMEN

A molecularly imprinted polymer (MIP) was synthesized using a polycyclic aromatic hydrocarbon (PAH) standard as a template, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, and acetonitrile as a porogen. This polymer was used as a solid phase adsorbent for the quantitative enrichment of PAHs in coastal sediments, atmospheric particulates, and industrial effluents. The MIP selective adsorption capacity for PAHs started reducing when the chemical oxygen demand (COD) and total dissolved solids (TDS) was more than 800 mg L(-1) in the targeted environmental samples. The adsorption stability of the MIP was tested by the consecutive contact of environmental samples, and it was shown that the performance of the MIP did not vary after 10 enrichments and desorption cycles. Recoveries of eight PAH compounds, extracted from 10 g of coastal sediments and 1 L of industrial effluent spiked with 10 microL of standard PAHs, showed recoveries between 85 and 96%. The fluorescence spectrophotometer limit of detection of PAHs varied from 10 to 30 etag L(-1) in industrial effluent and from 0.1 to 2.9 etag kg(-1) in solid samples (coastal sediment and atmospheric particulates), and this indicates that the environmental analytical method is significantly sensitive, when compared with other commonly used methods such as gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry.


Asunto(s)
Contaminantes Ambientales/análisis , Compuestos Policíclicos/análisis , Polímeros/química , Espectrometría de Fluorescencia/métodos , Adsorción , Impresión Molecular , Propiedades de Superficie
14.
Environ Monit Assess ; 146(1-3): 191-201, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18095178

RESUMEN

To meet the growing energy demand worldwide, oil and gas exploration and production activities have increased rapidly both in onshore and offshore areas. The produced oil from the ocean bed is transported onshore either by ship or pipeline. This has increased the risk of oil spill in the coastal area. In order to prepare an emergency preparedness plan and to assess the magnitude of risk involved in transporting and offloading oil, oil spill simulation studies play an important role. This paper describes a simulation of oil spill in coastal bay of Arabian Gulf where new developments are taking place using MIKE 21 model. The developments include a diesel based thermal power plant near Sir Baniyas Island, which is an ecological fragile area. Based on the project activity, two probable scenarios, one for diesel leak (250 m3/h) for 1 h and the other for instantaneous spill (500 m3) are considered. The MIKE 21 model was calibrated for hydrodynamics using measured field data followed by diesel-spill simulation to track its movement in the Arabian Gulf. The results for both leak and instantaneous spill indicate that spilled diesel will not move towards the Sir Banyas Island and more than 45% of the diesel will be evaporated within 48 h of oil spill. Based on the results, a clean up and contingency plan is proposed to mitigate the adverse impacts arising due to diesel spill in the study area.


Asunto(s)
Simulación por Computador , Combustibles Fósiles/análisis , Agua de Mar/química , Arabia
15.
Bull Environ Contam Toxicol ; 79(4): 384-7, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17713713

RESUMEN

Heavy metals composition of foods is of immense interest because of its essential or toxic nature. In view of this, we determined concentrations of select heavy metals from food items such as, potato chips and biscuits that were obtained from Nagpur City, India. The present study revealed preferred digestion method for different heavy metal recovery. The accumulation trend for Potato chips was in following order Fe > Al > Zn > Ni > Cu > Mn > Co > Cr > Pb and Cd, while for Biscuits it was Al > Fe > Zn > Ni > Mn > Co > Cr > Pb > Cu and Cd.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Contaminación de Alimentos/análisis , Residuos Industriales , Metales Pesados/análisis , Ciudades , Contaminantes Ambientales/química , Contaminantes Ambientales/metabolismo , India , Metales Pesados/química , Metales Pesados/metabolismo
16.
Environ Monit Assess ; 133(1-3): 87-98, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17286178

RESUMEN

Stratospheric input and photochemical ozone formation in the troposphere are the two main sources determining the ozone levels in the surface layer of the atmosphere. Because of the importance of ozone in controlling the atmospheric chemistry and its decisive role in the heat balance of atmosphere, leading to climate change, the examination of its formation and destruction are of great interest. This study characterized the distribution of Ground level Ozone (GLO) in Chandrapur district is lying between 19 degrees 25'N to 20 degrees 45'N and 78 degrees 50'E to 80 degrees 10'E. Continuous ozone analyzer was used to quantify GLO at thirteen locations fixed by Global Positioning System (GPS) during the winter of 2005-2006. The daily GLO at all the locations ranged between 6.4 and 24.8 ppbv with an average and standard deviation of 14.9 +/- 6.5 ppbv. The maximum and minimum concentration occurs during 1300-1600 h and 0300-0500 h may be due to high solar radiation facilitating photochemical production of O(3) and downward mixing from the overlying air mass and in situ destruction of ozone by deposition and/or the reaction between O(3) and NO. GIS based spatial distribution of GLO in Chandrapur district is indicates that the central core of the district and southern sites experienced elevated levels of GLO relative to the northern and western areas. The sites near by Chandrapur city are particularly affected by elevated GLO. The average variation of GLO with temperature shows a significant correlation of r = 0.55 indicating a direct relationship between GLO and temperature. Similarly an attempt has been made to compare the GLO monitored data in Chandrapur district with the reported values for other locations in Indian cities. This generated database helps regulatory agencies to identify locations where the natural resources and human health could be at risk.


Asunto(s)
Contaminantes Atmosféricos/análisis , Minas de Carbón , Ozono/análisis , Sistemas de Información Geográfica , India
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