Bioaccumulation of heavy metals in fish tissues of a freshwater lake of Bhopal

Contamination of heavy metals, namely, lead, cadmium, zinc, nickel, copper, chromium and mercury was evaluated in the samples of water and tissues of Labeo rohita and Ctenopharyngodon idella of Upper Lake of Bhopal collected during summer, rainy and winter seasons of 2005–2006. Different organs of the fishes accumulated varying quantities of different heavy metals. In L. rohita, accumulation of heavy metals was in the sequence liver > kidney > gills > muscles, and in C. idella, it was gills > liver > kidney > muscles. Zn was the highest accumulating metal in fish, whilst Hg was the lowest and was well corroborated with those of water. The values of heavy metals were so far well within the maximum permissible standard value of heavy metals for drinking water and for fish culture as prescribed by various national and international agencies.     

Treatment technologies for sustainable management of wastewater from iron and steel industry — a review

Environmental Science and Pollution Research - The iron and steel industries are a vital driving force for propelling the nation’s economic growth. In 2019, to boost the economy and to...     

Assessing Respiratory Morbidity Through Pollution Status and Meteorological Conditions for Delhi

The study focuses on assessing the status of respiratory morbidity in Delhi over a four years period from 2000–2003. An attempt was made to investigate the role of important pollutants (SO₂, NO₂, SPM and RSPM) and various meteorological factors (temperature minimum & maximum, relative humidity at 0830 and 1730 hrs. and wind speed) in being responsible for respiratory admissions on account of COPD, asthma and emphysema. The study showed that winter months had greater exposure risk as pollutants often get trapped in the lower layers of atmosphere resulting in high concentrations. Statistical analysis revealed that two pollutants have significant positive correlation with the number of COPD cases viz., SPM (r = 0.474; p < 0.01) and RSPM (r = 0.353; p < 0.05), while a meteorological factor temperature (minimum) has a significant negative correlation (r = −0.318; p < 0.05) with COPD. Stepwise multiple regression analysis was performed for COPD as dependent variable and R² value of 0.33 was obtained indicating that SPM and RH(1730) were able to explain 33 percent variability in COPD. The partial correlation of SPM and RH(1730) on COPD was higher than any other combination and therefore they can be regarded as important contributing variables on COPD.     

Spatial variability and temporal changes in the trace metal content of soils: implications for mine restoration plan

Trace metals in soils may be inherited from the parent materials or added to the system due to anthropogenic activities. In proposed mining areas, trace metals become an integral part of the soil system. Usually, researchers undertake experiments on plant species selection (for the restoration plan) only after the termination of mining activities, i.e. without any pre-mining information about the soil-plant interactions. Though not shown in studies, it is clear that several recovery plans remain unsuccessful while carrying out restoration experiments. Therefore, we hypothesize that to restore the area effectively, it is imperative to consider the pre-mining scenario of metal levels in parent material as well as the vegetation ecology of the region. With these specifics, we examined the concentrations of trace metals in parent soils at three proposed bauxite locations in the Eastern Ghats, India, and compared them at a spatio-temporal scale. Vegetation quantification and other basic soil parameters accounted for establishing the connection between soil and plants. The study recorded significant spatial heterogeneity in trace metal concentrations and the role of vegetation on metal availability. Oxidation reduction potential (ORP), pH and cation exchange capacity (CEC) directly influenced metal content, and Cu and Ni were lithogenic in origin. It implies that for effective restoration plant species varies for each geological location.     

Central Composite Design Model to Study Swelling of GrA-cl-poly(AAm) hydrogel and Kinetic Investigation of Colloidal Suspension

In the present study, the flocculation behavior of crosslinked copolymer GrA-cl-poly(AAm) hydrogel has been studied for the removal of turbidity from waste water. Sodium borohydride has been used for the reduction of the Gum rosin acids by which it gets converted into rosin alcohols. The reduced Gum rosin alcohol was crosslinked by the use of MBA and copolymerized with acrylamide using KPS as a redox initiator. Synthesized sample was then optimized for reaction conditions like reaction time, reaction temperature and the amount of solvent, monomer concentration, initiator concentration and pH of the reaction medium in order to get maximum percentage swelling. Synthesized samples were characterized using Fourier transform infrared spectroscopy, scanning electron of microscopy and X-ray diffraction techniques. Response surface methodology (RSM) based central composite design was used to study the effect of pH of swelling medium and temperature to maximize the percentage swelling. A statistical model (ANOVA) predicted pH 7.0 and temperature 40?°C as optimum operating conditions in order to get maximu swelling. GrA-cl-poly(AAm) hydrogel was found to be pH and temperature sensitive. Kaolin has been employed as a coagulant. The flocculation efficiency of the synthesized polymer was studied as a function of polymer dose, temperature and pH of the solution. GrA-cl-poly(AAm) observed to show maximum flocculation efficiency (95%) with 70mgL^?1 polymer dose in pH 5.0 at 30?°C. The adsorption capacity of malachite green dye removal (95%) was also studied with this synthesized polymer. The results validate that GrA-cl-poly(AAm) hydrogel has significant flocculation and dye removal properties and can be employed as an effective and low-cost material for removal of impurities from waste water.     

Determining groundwater quality using indices and multivariate statistical techniques: a study of Tosham block,Haryana, India

Environmental Geochemistry and Health - Water is the most important component for human survival and often the most misused one. The present study deals with the assessment of groundwater quality...     

Non-point source-driven carbon and nutrient loading to Ganga River (India)

This study was designed to test whether the atmospheric deposition (AD) significantly influences gross primary productivity (GPP) and dissolved organic carbon (DOC) build-up in the Ganga River. We collected data for three consecutive years (2012–2014) along with 37 km river stretch with respect to AD-input of carbon, nutrients, and surface runoff chemistry to relate changes in the river water. We found strong linkages among carbon and nutrients in AD, surface runoff and in the river. The concentration of DOC in the river was highest in the rainy season while those of dissolved inorganic nitrogen and dissolved reactive phosphorus were highest in winter. Spatio-temporal changes in DOC indicated dependence on point- and non-point sources and within-system DOC build-up. The GPP in the river increased consistently over time and significantly correlated with AD-N (R^2?=?0.96, p?<?.001) and AD-P (R^2?=?0.97, p?<?.001). Basin level extrapolation showed that the Ganga River Basin receives 1.81?Tg organic-C, 2.77 Tg reactive-N, and 130?Gg reactive-P annually through atmospheric deposition. Non-point source contributions of carbon and nutrients to the river were substantially higher than those of point sources. The study has relevance for regional scale carbon and nutrient budgeting and action plans for integrated river basin management.     

Monitoring water quality of Coimbatore wetlands, Tamil Nadu, India

Signs of wetland-water quality degradation have been apparent for decades, especially in those wetlands situated in the vicinity of cities and human habitations. Investigation on four urban wetlands of Coimbatore have been undertaken to assess the water quality with reference to pollution from various sources. The pH and total dissolved solids (TDS) values of the lakes were found to be different from those reported almost a decade back. The concentrations of phosphate and sulphate were much lower than the earlier reported values. The present scenario states that though the biochemical oxygen demand and chemical oxygen demand values were lower for the Ukkadam wetland, the values for Perur wetland have shown a gradual increase. Alkalinity and chloride concentrations were thrice higher than the previous findings. Electrical conductivity and TDS ranged from 303.67 to 4,456.7 μS/cm and from 169 to 2,079.3 mg/l, respectively, and were positively correlated with chloride and sulphate (P?< 0.05). These changes are a reflection of the environmental changes happening in the cityscape of the Coimbatore, a fast-growing city in south India.