Browsing by Author "Devendra Mohan"

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A Critical Appraisal of Biomedical Waste Management in Uttar Pradesh
(Springer Science and Business Media Deutschland GmbH, 2022) Praveen Kumar Tiwari; Surendra Kumar Pandey; Rohit Kushwaha; Sonam; Kapil Malviya; Markandeya; Sheo Prasad Shukla; Devendra Mohan
Bio-medical waste is the waste generated from hospitals, including infectious waste, and has a high potential for causing injury and infections to humans as well as to the environment. Effective bio-medical waste management is the requisite parameter for a healthy and unpolluted environment. It is a social and legal responsibility of the medical community and common people to participate in the proper hygienic waste disposal actively and lead the environment free from various infectious diseases. BMW is precarious in the constitution and is different from general municipal waste; hence, it requires a unique approach and handling to avoid environmental and human health risks. The government of India made a statutory requirement for appropriate handling and disposal of bio-medical waste with the publication of gazette notification in July 1998 and further making required changes in it. This article explains various components, techniques for remediation, and consequences of improper disposal of BMW and provisions of BMW management in India. It also gives a brief overview of bio-medical waste management of hospitals in Uttar Pradesh. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
A review on health impacts, monitoring and mitigation strategies of arsenic compounds present in air
(Elsevier Ltd, 2021) Yogesh Kumar Vishwakarma; Sonam Tiwari; Devendra Mohan; R.S. Singh
Arsenic, even in trace concentration presents several adverse impacts on human health and are classified among carcinogenic species. The subsequent health concerns owing to consumption of arsenic contaminated water has been widely reported, however, the presence and effects of arsenic through air still remains to be explored thoroughly, due to the availability of limited research and literature; the reason being difficulty in estimation of arsenic compounds in gaseous or particulate associated form. The objective of the current review is to present a detailed picture of sources, estimation techniques and control strategies available currently and propose futuristic approaches for abatement of the problem. A summary of the studies conducted globally has been included in the review with an objective to figure out the occurrence and exposure to arsenic in different parts of the world, exposure assessment and control strategies followed to overcome the problem. Studies on dispersion of As in gaseous or particulate form has also been discussed, on the basis of ground observation as well as predicted models. © 2021 The Authors
A way to identify groundwater potential zones (GWPZS) in rocky Terrains (India)
(EM International, 2016) Brijesh Kumar; Virendra Kumar Chandola; Devendra Mohan; Kanhu Charan Patra
The objective of this study is to explore the way to find out sound groundwater potential zones in draught-prone rocky terrains. In the present paper, groundwater potential zones have been delineated using two aquifer parameters viz. transmissibility (T), storability (S) and GIS techniques. The transmissibility (T) and storability (S) values for different well location are being used to prepare two thematic raster layers viz. Isotransmissibility and Isostorability map using kriging interpolation method. Thereafter, these two maps have allocated an equal weight in weighted overlay technique of ArcGIS to get the weighted map. Thus, the obtained weighted map is groundwater potential zones map (GWPZs) and has six groundwater potential zones, viz., very good, good, moderate, poor, very poor and nil. The prepared thematic maps may prove very supportive to enhance planning and management of groundwater resources in these rocky terrains. Copyright © EM International.
An overview of human health risk from opium alkaloids and related pharmaceutical products pollution in aquatic ecosystems
(Elsevier, 2022) Sonam; Markandeya; Y. Shiv Shankar; Prashant Bhushan; Deepak Gautam; Pankaj Kumar; S.P. Shukla; Devendra Mohan
Fresh water is a valuable resource, but the increase in pollution of aquatic ecosystem is a matter of concern. Industries are rapidly budding in India, which discharge their effluents into the water bodies either directly or after treating partially. Pharmaceutical compounds are very important, but at the same time, release toxic contaminants in the environment. Pharmaceutical products impose huge effects on aquatic environment, resulting in acute and chronic damages, reproductive damage, behavioral changes, and inhibition of cell proliferation. The effluents produced from alkaloid processing industries is highly polluted having low pH, high COD, BOD5, sulfate, and TKN values, and a characteristic dark brown color. A number of physical as well as biological processes occurring in aquatic ecological unit may cause reduction of trace concentrations of pharmaceutical compounds. Treatment of wastewater generated from alkaloid processing is a challenging task because of the complex mixture of contaminants. Several methods for the treatment of these wastes, such as anaerobic and aerobic biological treatment, anaerobic treatment with membrane treatment, and aerobic treatment with catalytic wet air oxidation have been reported. Studies have also been conducted on physicochemical treatment in combination with activated sludge process. Membrane processes and Fenton oxidation have also been investigated as a post-treatment method. Membrane technologies are desirable for industrial wastewater treatment as no external addition of chemicals is required. © 2022 Elsevier Inc. All rights reserved.
Assessment of groundwater quality with special reference to arsenic in Nawalparasi district, Nepal using multivariate statistical techniques
(Springer Verlag, 2014) Ishwar Chandra Yadav; Ningombam Linthoingambi Devi; Devendra Mohan; Qi Shihua; Surendra Singh
Groundwater is a precious resource for humankind not only in Nepal but also across the globe due to its diverse functions. A total of 48 groundwater samples were collected from three villages of Nawalparasi district, Nepal, during pre-monsoon and monsoon to estimate the overall groundwater quality and to identify the sources of contamination with emphasis on arsenic (As). The average concentrations of all tested groundwater quality parameters (temp., pH, EC, ORP, Ca2+, Mg2+, Na+, K+, Cl-, F-,SO4 2-, PO4 3-, HCO3 -, NO3 -, Cu, Ni, Mn, Cd, Pb, Fe, Zn, Cr, and As) were well within permissible limits of WHO for drinking water, except for Ni, Cd, Pb, Cr, and As. Concentration of As ranged from 60 to 3,100 μg L-1 and 155 to 1,338 μg L-1 in pre-monsoon and monsoon, respectively. The Piper diagram of the groundwater chemistry showed groundwater of Nawalparasi belongs to Ca-Mg-HCO3 and Mg-HCO3 water type with HCO3 - as dominant ions. As content in the study area was negatively correlated with Fe in pre-monsoon, while it was positively correlated in monsoon. Furthermore, As was negatively correlated with oxidation reduction potential suggesting reducing condition of groundwater. Principal component analysis revealed seven major factors that explained 81.996 and 83.763 % of total variance in water quality in pre-monsoon and monsoon, respectively. The variance of water quality was related mainly with the degree of water-rock interaction, mineralization, and anthropogenic inputs. © 2013 Springer-Verlag Berlin Heidelberg.
Bioremediation of contaminated soils: An overview
(Springer Singapore, 2017) Manisha Mishra; Devendra Mohan
Bioremediation has attracted attention of scientists and biotechnologists for environmental control and it employs biological agents mainly microorganisms like yeast, fungi, algae, or bacteria to treat contaminated soils or water derived in the process applied for treatment of such sites. Microbial bioremediation for in-situ removal of organic pollutants, heavy toxic metals, radionuclides, etc., can be applied successfully. Specific bioremediation technologies can also be developed based on toxicity of contaminants and the site conditions. As a component of bioremediation, application of plants for removal of contaminants from environment, known as phytoremediation, can also be made and hyperaccumulator species are capable of accumulating toxic metals about 100 times higher than those typically found in common plants. Uses of a number of biosorbents for soil treatment by uptake of ionic species present even up to tracer levels (around 10-7 M) has been demonstrated successfully. Molecular approaches can be effectively applied to enhance bioremediation. This paper presents an overview of various studies carried out on bioremediation of contaminated soils. © Springer Nature Singapore Pte Ltd. 2017. All rights reserved.
Bioremediation of Imidacloprid in a Stirred Tank Reactor Using Bacterial Consortium: Kinetic Analysis and Toxicity Assessment
(American Chemical Society, 2023) Sonam Tiwari; Pranjal Tripathi; Devendra Mohan; R.S. Singh
Imidacloprid is an insecticide of systemic nature that exhibits an adverse impact on several non-target organisms. In the present study, potential bacteria have been isolated and used for biodegradation of imidacloprid in batch studies and stirred tank reactor. The optimum process condition for degradation has been found to be at pH 7, a temperature of 35 °C, and a shaking speed of 150 rpm. Maximum degradation of 78% has been achieved by the bacterial consortium in the batch study, while, in the reactor, it increases to 90%. Kinetics analysis suggests that the Teisser model best fits the experimental data, with a correlation coefficient (R2) of 0.98. Ecotoxicological assessment using luminescent bacteria reveals 40% and 90% inhibition in luminescence in the case of untreated sample upon exposure for 30 min and 24 h, respectively, while the values obtained in the case of treated samples are 9% and 29%, respectively. Cytotoxicity assessment indicates 60% reduction in cell proliferation in untreated samples and <10% cell proliferation inhibition in treated samples, indicating a considerable decrease in toxicity post-bacterial treatment. © 2023 American Chemical Society
Current status of groundwater arsenic and its impacts on health and mitigation measures in the Terai basin of Nepal: An overview
(2011) Ishwar C. Yadav; Umesh P. Dhuldhaj; Devendra Mohan; Surendra Singh
Nepal is located in the vicinity of Himalayas. Nearly 47% (11 million) of the total Nepalese population lives on the flat lands located in the southern part of the country, the Terai region. The majority (90%) of people living in the Terai region of Nepal depends on groundwater as their primary source of potable water. Out of 24 674 tested wells in the Nawalparasi district approximately 7896 wells (32%) had As concentrations greater than 10 μg·L-1 (safe-water limit set by WHO). In addition, 3676 wells (14.9%) had As concentrations greater than 50 μg·L-1 (standard permissible limit proposed by Nepal). However, at present, none of the wells in the Terai districts of Nepal are free from As. Based on sedimentaquifer studies, the Siwalik Hills and the higher Himalayas are assumed to be the possible sources of As in the Terai region. Leaching of As from natural rocks has been the main source of groundwater contamination in Nepal. However, little is known about the mechanism of As release in the Terai groundwater. High levels of As contamination in the drinking water poses a serious risk to the health of resident living in the Terai plain regions. In the region, 23% (2.53 million, based on WHO guideline of μg·L -1) and 5% (0.5 million, Nepal's standard of >50 μg·L-1) of population are at the risk of As exposure. Chronic exposure to As imparts characteristic skin manifestations (pigment change), melanosis and keratosis. The prevalence of arsenicosis was found to be 3.6%, 0.9%, and 0.7% in Nawalparasi, Rupandehi, and Kapilavastu districts, respectively. Arsenicosis is most prevalent among the male population, especially those in their late 50s. The most promising approach for the removal of As to acceptable levels include the use of Gagri filters and iron-assisted bio-sand filters. Here, we review the current status of groundwater arsenic and its impacts on health and mitigation measures in the Terai region of Nepal.
EMERGING POLLUTANTS: OCCURRENCE, FATE, TOXICOLOGICAL IMPACTS AND REMOVAL TECHNOLOGIES
(Nova Science Publishers, Inc., 2021) Sonam; Rohit Kushwaha; Pranjal Tripathi; R.S. Singh; Devendra Mohan
The presence of emerging contaminants in the effluents of wastewater treatment plants is a matter of growing concern. Emerging contaminants are chemical compounds including pesticides, pharmaceuticals, hormones, other endocrine disruptors, surfactants, surfactant metabolites, industrial additives and personal care products. The occurrence of various emerging pollutants is often related to discharges from treatment plants, as a consequence of the extensive use of such compounds and the lack of efficient removal technologies. The list of compounds considered as emerging pollutants has increased significantly in recent years leading to a number of parent compounds and transformation products found in wastewater effluent, surface and groundwater and drinking water. The identification and quantification of these compounds in water or wastewater has become a major scientific task requiring highly sophisticated analytical methodologies which can detect even minute levels of pollutants. The quantification of emerging contaminants in complex waste water samples recognized through non-target screening approaches, has played a key role in the planning and design of water treatment facilities. A majority of emerging contaminants do not have standard regulations and could lead to lethal effects on human and aquatic life even at small concentrations. The conventional primary and secondary water treatment plants do not remove or degrade these toxic pollutants efficiently and hence need cost effective tertiary treatment method. Currently, membrane filtration technologies and the use of advanced oxidation processes (AOPs) are widely studied for the removal of micropollutants, either in wastewater or in drinking water. Among these treatments, the most relevant processes include ozonation, photocatalysis, electrochemical reactions, membrane bioreactors, nanofiltration or ultrafiltration, reverse osmosis and adsorption. Adsorption is a promising method for removal of pollutants, because of low initial cost for implementation, highly-efficient and has simple operating design. Research has shown that the application of different adsorbents such as activated carbons, modified bio-chars, nano-adsorbents (carbon nanotubes and graphene), composite adsorbents, and others are being used for removal of emerging contaminants from water and wastewater. Technologies based on hydrogen peroxide oxidation, such as Fenton or others activated by UV and ultrasound have also proved significant. The various sources and types of emerging pollutants along with their toxicological effect on health and environment have been highlighted. The review further focusses on the information about advancements in wastewater treatment technologies such as constructed wetland (CW) and advanced oxidation processes (AOPs) and the fate of emerging contaminants during these treatments. The ecological effects of these contaminants and their by-products formed during advanced treatment processes as well as different analytical techniques for the analysis of emerging contaminants have also been discussed. © 2021 by Nova Science Publishers, Inc.
Fluoride removal using capacitive deionization process employing carbon electrodes
(John Wiley and Sons Inc, 2023) Praween Kumar; Rohit Kushwaha; Devendra Mohan
Contamination of groundwater with fluoride poses adverse health impacts for humans. This study aims to investigate the feasibility of capacitive deionization process for fluoride removal from groundwater. In this study, composition of binder content was optimized and the experiments were performed using a lab scale batch reactor. Effect of initial ionic concentration on the removal efficiency was also studied. The electrodes were also evaluated for their efficiency to remove arsenic. The maximum fluoride removal efficiency obtained was 99.1% for the PVDF content of 15% (w/w) whereas for arsenic it was only 52%. The voltage applied across the electrodes was only 1.2V. Electrodes were tested for their physical strength and their characterization was done using Scanning Electron Microscope. Sorption kinetics of the electrodes was also investigated and was found that the adsorption followed elovich model most closely. © 2022 Wiley Periodicals LLC.
Fluoride Removal Using Capacitive Deionization with Electrodes Coated on Both Sides
(American Society of Civil Engineers (ASCE), 2025) Devendra Mohan; Rohit Kushwaha; Divakar Bhaskar; Sonam Tiwari; Vikas Srivastava; Markandeya Tiwari; Sheo Prasad Shukla
The present study was focused on the fabrication of a device to remove fluoride using capacitive deionization (CDI). The conventional CDI device was modified such that electrodes coated on both sides could be used. The electrodes were prepared by mixing activated carbon (AC), graphite powder (GP), polyvinylidene fluoride (PVDF), and N, N-dimethylacetamide (NDMAc). The proportion of the constituents was varied to obtain the optimum composition for the most efficient electrodes. Electrodes with composition of AC:GP:PVDF=70:16:14 wt% were found to have sufficient mechanical strength and favorable capacitive characteristics for the electrosorption of fluoride ions. The maximum removal efficiency obtained with single-side coated electrodes was 90.38%±1.33% under 45 min, whereas for electrodes coated on both sides, the maximum efficiency achieved was 97.38%±0.44% under 25 min. The study was performed using a batch-type CDI device. The device could operate effectively at a low voltage of 1.5 V, making it an environment-friendly and efficient technology. The cost involved for the treatment of water was USD 0.039/L. © 2024 American Society of Civil Engineers.
Impacts assessment of municipal solid squander dumping in riparian corridor using multivariate statistical techniques
(Springer Singapore, 2017) Abaidya Nath Singh; Deepak Kumar Gautam; Pankaj Kumar; Devendra Mohan
Crumbling soil quality and reduction in vegetation plenitude are grave outcomes of open squanders dumping which have brought about growing public concern. The center of the present study is to assess the contribution of open squander dumping in riparian soil contamination and its impact on plant assorted qualities in riparian corridor of river Varuna. Surface soil sample (n = 6 + 2) was gathered from both the open squander dumping and control site. The assorted qualities of vegetation were learned at both sites. Significant changes were seen in the soil attributes of the dumping sites. Soils at the dumping indicated high pH, TDS and EC regime in contrast with control site. The assorted qualities of vegetation were also learned at both sites. A comparable pattern was seen in plant assorted qualities. Control site indicated differentiated assortment of plants, i.e., 12 plant species while this number decreased at the dumping sites. The principal component analysis created three significant components explaining 95.764 of the variance in the data attributable to open dumping effect. Hierarchical cluster analysis grouped six-dumping sites into three clusters having similar characteristics and source of contamination, i.e., moderate and highly polluted dumping sites. © Springer Nature Singapore Pte Ltd. 2017. All rights reserved.
Phototrophic cultivation of NaCl-tolerant mutant of Spirulina platensis for enhanced C-phycocyanin production under optimized culture conditions and its dynamic modeling
(Blackwell Publishing Inc., 2018) Apurva Gupta; Devendra Mohan; Rishi Kumar Saxena; Surendra Singh
Commercial cultivation of Spirulina sp. is highly popular due to the presence of high amount of C-phycocyanin (C-PC) and other valuable chemicals like carotenoids and γ-linolenic acid. In this study, the pH and the concentrations of nitrogen and carbon source were manipulated to achieve improved cell growth and C-PC production in NaCl-tolerant mutant of Spirulina platensis. In this study, highest C-PC (147 mg · L−1) and biomass (2.83 g · L−1) production was achieved when a NaCl-tolerant mutant of S. platensis was cultivated in a nitrate and bicarbonate sufficient medium (40 and 60 mM, respectively) at pH 9.0 under phototrophic conditions. Kinetic study of wildtype S. platensis and its NaCl-tolerant mutant was also done to determine optimum nitrate concentrations for maximum growth and C-PC production. Kinetic parameter of inhibition (Haldane model) was fitted to the relationship between specific growth rate and substrate concentration obtained from the growth curves. Results showed that the maximum specific growth rate (μmax) for NaCl-tolerant mutant increased by 17.94% as compared to its wildtype counterpart, with a slight increase in half-saturation constant (Ks), indicating that this strain could grow well at high concentration of NaNO3. C-PC production rate (Cmax) in mutant cells increased by 12.2% at almost half the value of Ks as compared to its wildtype counterpart. Moreover, the inhibition constant (Ki) value was 207.85% higher in NaCl-tolerant mutant as compared to its wildtype strain, suggesting its ability to produce C-PC even at high concentrations of NaNO3. © 2017 Phycological Society of America
Predicting phytoplankton growth and dynamics in relation to physico-chemical characteristics of water body
(2009) Naveen K. Sharma; Devendra Mohan; Ashwani K. Rai
In recent times, frequency and severity of algal blooms has increased significantly. To control their expansion, it is essential to identify the factors responsible for blooming of waters. Nutrient over-enrichment (mainly due to anthropogenic activities) and environmental factors (including the climate change) are considered the major catalyst for onset, proliferation, and development of blooms. A eutrophic subtropical water reservoir (Durgakund Pond, Varanasi) was sampled for 2 years (2000-2002), and data were obtained on various physico-chemical factors such as temperature, dissolved oxygen, pH, phosphorus (PO4 - and other P forms), nitrogen (NO3 -, NO2 -, and NH+ 4), chloride, iron, and phytoplankton biomass in terms of chlorophyll a, total protein, and carbohydrate content. Linear regression models that developed indicated that phosphorous, nitrogen, and iron had maximal impact on phytoplankton growth. Physical factors, though vital, had an indirect effect in facilitating the interaction among various nutrients and their availability. © 2009 Springer Science+Business Media B.V.
Spatial distribution of arsenic in groundwater of southern Nepal
(2012) Ishwar Chandra Yadav; Surendra Singh; Ningombam Linthoingambi Devi; Devendra Mohan; Madhav Pahari; Pratap Singh Tater; Birendra Man Shakya
Groundwater is a significant source of drinking water in virtually all parts of the world. Protected groundwater is safer to drink, in terms of microbiological quality, than is water from open dug wells and ponds (World Bank 2005). However, groundwater is notoriously prone to chemical and other types of contamination, such as arsenic (As) that derives from natural or anthropogenic sources. © 2012 Springer Science+Business Media, LLC.