Rajendra Dobhal

Arsenic speciation analysis and remediation techniques in drinking water

Abstract Arsenic is present in environment in trace amounts in rocks, soil, water and air but its toxicity effects are highly dependent on its chemical forms; inorganic and organic. There is a direct association between elevated arsenic exposure through drinking water and prevalence of different types of cancers. Present review describes the brief account of arsenic chemistry with reference to water and environment which is relevant to its toxicity arising out of different arsenic species and finally its remediation technologies. The quantification of arsenic species is difficult owing to the low concentration of arsenic in drinking water which is relatively lower than detection limits of modern analytical methods. New hyphenated techniques with more advanced tools have therefore, been discussed in the present paper which are being used in arsenic speciation analysis. The present review also highlights the importance to identify and quantify each chemical species of arsenic as more than 20 arsenic compoun...

A review on characterization and bioremediation of pharmaceutical industries’ wastewater: an Indian perspective

During the past few decades, pharmaceutical industries have registered a quantum jump contributing to high economic growth, but simultaneously it has also given rise to severe environmental pollution. Untreated or allegedly treated pharmaceutical industrial wastewater (PIWW) creates a need for time to time assessment and characterization of discharged wastewater as per the standards provided by the regulatory authorities. To control environmental pollution, pharmaceutical industries use different treatment plans to treat and reuse wastewater. The characterization of PIWW using advanced and coupled techniques has progressed to a much advanced level, but in view of new developments in drug manufacture for emerging diseases and the complexities associated with them, better sophisticated instrumentation and methods of treatment are warranted. The bioremediation process to treat PIWW has undergone more intense investigation in recent decade. This results in the complete mineralization of pharmaceutical industries’ wastewater and no waste product is obtained. Moreover, high efficiency and low operation cost prove it to be an effective tool for the treatment of PIWW. The present review focuses on the characterization as well as bioremediation aspects of PIWW.

Chemical composition and antibacterial properties of the essential oil and extracts of Lantana camara Linn. from Uttarakhand (India)

Abstract Objective The purpose of this study was to evaluate the essential oil composition as well as antibacterial activities of essential oil and leaves extracts of Lantana camara against five bacterial strains. Methods Essential oil was obtained by hydro-distillation from the leaves and analyzed by GC and GC-MS. The antibacterial activities of essential oil and the leaves extracts were tested by using disk diffusion method against five bacterial strains. Results Thirty seven compounds were identified representing 98.11% of the total oil, of which trans-caryophyllene (13.95%), bicyclogermacrene (9.77%), ±-curcumene (8.57%), sabinene (8.28%), (E)-citral (6.90%), 1,8 cineole (5.06%), ±-pinene (4.03%), -terpinene (3.83%) and germacrene D (3.13%) were detected as major components. In respect to the antibacterial activities, essential oil showed the high degree of sensitivity against Micrococcus luteus, Escherichia coli, Staphylococcus aureus and Bacillus cereus except Pseudomonas aeruginosa while extracts of leaves obtained through petroleum ether, benzene, methanol and water exhibited good to moderate antimicrobial activity against all tested bacterial strains. Conclusions The present study suggested that M. luteus showed best zone of inhibition for the essential oil as well as aqueous extract among all the tested bacterial strains. The most active extract can be subjected to isolation of the therapeutic antimicrobials to carry out further pharmacological evaluation.

Advanced and Hyphenated Techniques for Nano-Level Analysis of Iron in Water

The monitoring of iron in water sources has been and will be of immense importance because modern applications require accurate and reliable results of quantification of low levels of iron in water being used in specialized fields. Although iron in drinking water supplies is found to exist in four forms, Fe(II), Fe(III), iron bacteria, and organic iron, no single method is capable of nano-level analysis of all these forms of iron. Hence, various advanced and hyphenated techniques are being used for the determination of iron species in drinking water sources that give precise and reliable results and reduce human effort. The present article reviews the new generation of equipment and a variety of modified and hyphenated instrumental techniques for iron analysis. Additionally, this review describes detection limits of widely used hyphenated techniques for quantitative analysis of four forms of iron in water down to ultratrace levels.

Water quality evaluation of Himalayan Rivers of Kumaun region, Uttarakhand, India

Water quality of Himalayan rivers has been steadily deteriorating over several decades due to anthropogenic activities, dumping of treated or untreated effluents, poor structured sewerage and drainage system, etc. In the present study, the water quality of five important rivers namely, Gola, Kosi, Ramganga, Saryu and Lohawati rivers were investigated which flow through the different districts of Kumaun region of Uttarakhand Himalaya. The water of all these rivers serves as the major source for drinking and irrigation purposes in these districts of the Kumaun region of Uttarakhand. River water samples collected in pre-monsoon and post-monsoon seasons of the years 2011 and 2012 were analyzed for various water quality characteristics. Statistical analyses indicate positive correlation among most of the chemical parameters. Piper diagram illustrates that all the water samples fall in Ca–Mg–HCO3 hydrochemical facies, Moreover, the suitability of water for drinking purposes determined by water quality index indicated that river water in both the seasons is unsuitable. Irrigation water quality of all the river water was found suitable during both the seasons according to the result of sodium adsorption ratio, sodium percentage and residual sodium carbonate. The present study revealed that major factors contributing to deterioration of water quality of all the rivers might be eutrophication, tourism, anthropogenic and geogenic processes. Therefore, to restore the vitality and water quality of all these rivers, proper water resource planning programme should be developed.

Studies of River Water Quality Using River Bank Filtration in Uttarakhand, India

The poor water quality, bacterial contamination, seasonal variation, uncertainty in monsoon, lack of sustainability etc. are some major challenges of the water sector in the Himalayan region of India. To tackle the major problem of water quality, River Bank Filtration (RBF) has been applied in Uttarakhand as a domestic water pre-treatment technology. This technique is found to be effective for removal of turbidity and bacterial contamination present in surface water of four rivers of Uttarakhand, namely Alaknanda, Mandakini, East Nayar, and Pinder. The present paper reveals the improved water quality of rivers produced through RBF in a sustainable manner as compared to surface river water being supplied for drinking purpose. The classification of water quality using Pearson correlation followed by Piper trilinear and Chadha’s diagrams further provide support to the better water quality through RBF. Moreover, the results of Water Quality Index (WQI) also reflect the excellent water quality with ‘A-Grade’ of all river water samples obtained after RBF process in comparison to normal river water samples having good water quality with ‘B-Grade’ except the Srinagar site, where the river water sample was found to be unsuitable for drinking purpose with ‘E-Grade’. Alluvial deposits of RBF sites along the banks of the four rivers show the potential of replication of RBF at large scale in the hill state of Uttarakhand.

Application of Chemometric Techniques in the Assessment of Groundwater Quality of Udham Singh Nagar, Uttarakhand, India

In the present study, groundwater quality of district Udham Singh Nagar was evaluated using chemometric techniques viz. cluster, principal component and factor analyses to investigate the spatial variations of the most significant water quality parameters and to determine origin of pollution sources. Water samples collected from 6 sampling sites were analysed for 23 water quality parameters in pre- and post-monsoon seasons during the years 2010 and 2011. The concentration of alkalinity, total hardness, total dissolved solids, calcium, magnesium total coliform and faecal coliform of samples exceeded the Bureau of Indian Standard limits. Correlations among selected water quality parameters were statistically examined. Cluster analysis grouped 6 sampling sites into three clusters, i.e. less, moderate and high polluted, based on similarities of water quality characteristics. The principal component/factor analysis extracted four factors, which explain the ground water quality. Factor 1 (anthropogenic pollution) includes hardness, alkalinity, TDS calcium and magnesium, Factor 2 (hydrogeologic and agricultural pollution) includes turbidity, pH and nitrate, Factor 3 (industrial pollution) comprises

Population Genetic Study of Fagopyrum tataricum from Western Himalaya Using ISSR Markers

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