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Managing future air quality in megacities: co-benefits assessement for delhi(Atomspheric Environment) (Bhanarkar AD., Purohit P., Rafaj P., Amann M., Bertok I., Cofala J., Rao PS., HarshavarhanB., Kiesewetter Gregor, Sander Robert, Schöpp Wolfgang, Majumdar Dipanjali, Srivastava A., Deshmukh S., Kawarti A., Kumar R. ,186,,158-177,Year : 2018)
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Urbanization, population and economic growth in Indian megacities like Delhi have resulted in an increase in energy and transportation demand leading to severe air pollution and related health impacts, as well as to the rapid growth in the greenhouse gas emissions. In this study, an integrated assessment of air quality and climate policiesfor Indiancities –withaparticularfocuson NationalCapital TerritoryofDelhi,hasbeencarriedout.We have developed emission inventory of air pollutants and greenhouse gases for the base year (2010) and evaluated the impact ofcurrent policieson emission projections by2030 in the business-as-usual scenario. Emissions of coarse and ?neparticulate matter areprojected to be51% and 15%higher in2030 as compared to present. As the current legislations do not indicate progress towards the achievement of the Indian National Ambient Air Quality Standards in Delhi, we explored the e?ectiveness of additional emission control strategies with either advanced end-of-pipe emission controls or low carbon policies. Relative to the baseline scenario, the set of alternativepolicystrategieswouldreduceemissionsrapidlyin2030.Theresultsrevealedthatairqualitypolicies under various scenarios could also have co-bene?ts of reducing carbon emissions. At the same time, the results suggest that low carbon policies would be more e?cient to cut emissions as compared to advanced end-of-pipe emission control policies. However, their implementation could be limited by the availability of clean fuels. In the climate policy scenario, carbon emission in 2030 is estimated to decrease by 19% relative to baseline. Additional controls combined with low carbon policies like controlling non-industrial emissions create an opportunity to further enhance the scope for co-bene?ts and to attain the air quality standards in Delhi.
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Emission estimation of aromatic and halogenated VOCs from household solid fuel burning practices(International Journal of Environmental Science and Technology) (Verma M. , Pervez S. , Majumdar D. , Chakrabarty R. & Pervez Y. F. ,,,,Year : 2018)
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This study describes the emission factors (EFs) of 16 volatile organic compounds (VOCs) for the combustion of commonly used household solid fuels including coal balls (CB), fuelwood (FW), dung cakes (DC), crop residues (CR), and mixed fuels (MF: DC + FW), collected from ten states of India. Sum of 16 VOCs EF (g kg-1) have shown highest level (50.0 ± 22.7 g kg-1) for CB, followed by CR (23.71 ± 10.64 g kg-1), DC (19.08 ± 3.29 g kg-1), MF (15.77 ± 9.49 g kg-1), and FW (12.79 ± 5.69 g kg-1). These findings are multifold higher than those reported for biomass burning in test chamber studies. Benzene and dichloromethane EFs were found to be dominating among the aromatic and halogenated VOCs, respectively. Annual TVOCs emission estimates were evaluated to be 12.58 ± 5.92 Gg year-1 from household solid fuel burning practices. It was the 1/6th of TVOCs emission estimates (73 Gg year-1) from biomass burning in India during 2009.
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Perturbation of Background Atmospheric Black Carbon/PM1 Ratio during Firecracker Bursting Episode(Asian journal of atmospheric Environment) (Deepanjan Majumdar and Ashok Gangadhar Gavane
,11(4),,322-329,Year : 2018)
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Perturbation in ambient particulate matter (PM1, PM2.5, PM10) and black carbon (BC) concentrations was studied during a firecracker bursting episode in Diwali (Festival of Lights) celebrations in Nagpur, India. Firecracker bursting resulted in greater escalation in fine particulates over coarse particulates while PM2.5 was found to be dominated by PM1 concentration. On the Diwali day, daily mean concentration of PM2.5 and PM10 exceeded Indian National Ambient Air Quality Standards by over 1.8 and 1.5 times, respectively, while daily mean BC concentration on the same day was almost two times higher than the previous day. The BC/PM1 ratio reduced remarkably from about 0.26 recorded before firecracker bursting activity to about 0.09 during firecracker bursting on Diwali night in spite of simultaneous escalation in ambient BC concentration. Such aberration in BC/PM1 was evidently a result of much higher escalation in PM1 than BC in ambient air during firecracker bursting. The study highlighted strong perturbations in ambient PM1, PM2.5, PM10 concentrations and BC/PM1 during the firecracker bursting episode. Altered atmospheric BC/PM1 ratios could serve as indicators of firecracker-polluted air and similar BC/PM1 ratios in local and regional air masses might be used as diagnostic ratios for firecracker smoke.
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Arsenic in groundwater of West Bengal, India: A review of human health risks and assessment of possible intervention options.(Journal of Science of the Total Environment) (Bhowmick S., Pramanik S., Singh P., Mondal P., Chatterjee D., Nriagu J,40266,,856,Year : 2018)
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"This paper reviews how active research inWest Bengal has unmasked the endemic arsenismthat has detrimental effects on the health of millions of people and their offspring. It documents howthe pathways of exposure to this toxin/poison have been greatly expanded through intensive application of groundwater in agriculture in the regionwithin the Green Revolution framework. A goal of this paper is to compare and contrast the similarities and differences in arsenic occurrence in West Bengal with those of other parts of the world and assess the unique socio-cultural factors that determine the risks of exposure to arsenic in local groundwater. Successful intervention options are also critically reviewedwithemphasis on integrative strategies that ensure safewater to the population, proper nutrition, and effective ways to reduce the transfer of arsenic from soil to crops. While no universal model may be suited for the vast areas of the world affected with by natural contamination of groundwater with arsenic, we have emphasized community-specific sustainable options that can be adapted. Disseminating scientifically correct information among the population coupled with increased community level participation and education are recognized as necessary adjuncts for an engineering intervention to be successful and sustainable."
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Optimisation of laboratory arsenic analysis for groundwaters of West Bengal, India and possible water testing strategy(International Journal of Environmental Analytical Chemistry) (Kundu AK., Majumder S., Biswas A., Bhowmick S., Pal C., Mukherjee A., Majumder M., Chatterjee D,40266,,,Year : 2018)
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Regularmonitoring of arsenic (As) in groundwater is crucial frompublic health perspectives as millions of people are suffering due to use of contaminated aquifer water for drinking purposes. The routine analyses, especially in developing nations, are mostly done in localised government/non-government laboratories with limited resources, having the target of analysing large number of samples in each run. Thus apart from analytical sensitivity, cost-effectiveness of the method and eco-friendliness of the experimental operation are key surreptitious factors. This demands optimisation of total As measurement methods and finding a method that gives ‘optimumbenefit’ considering all these factors together. The present study therefore evaluates four common As (total) measurement methods [iodometric- colorimetric method, silver diethyl dithiocarbamate method, molybdenum blue method and hydride generation atomic absorption spectrophotometric (HG-AAS) method] practised in the Bengal Delta Plain, in view of their analytical sensitivity, related environmental hazard and experimental costs. It was found that the HG-AAS method is analytically more sensitive, whereas the iodometric-colorimetricmethod and the molybdenum blue method are better choices in terms of eco-friendliness and cost-effectiveness, respectively. However, when all three factors (analytical reliability, environmental hazard and cost) are considered simultaneously, themolybdenumbluemethodwas found to be placed first in the ‘optimum performance rank’ list. It was also found that both environmental hazard and cost play a more crucial role than analytical reliability, although this is case specific andwould differ from place to place around the globe. Finally based on the results, we have hypothesised a water testing strategy for developing countries such as India where the molybdenum blue method can be adapted as a screening method and later the HG-AASmethod can be used to precisely identify the groundwater samples with As concentration below the WHO drinking water guideline value of 10 g/L.
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Arsenic retention in cooked rice: Effects of rice type, cooking water, and indigenous cooking methods in West Bengal, India(Journal of Science of the Total Environment) (Mandal U., Singh P., Kundu AK., Chatterjee D., Nriagu J., Bhowmick S.,40266,,,Year : 2018)
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This study evaluated the concentration of arsenic in paired raw and cooked rice prepared by individual households in arsenic-endemic rural area of West Bengal. The aim was to investigate how the cooking habits of rural villagers of West Bengal might influence the arsenic content of rice meals. It was found that the use of arsenicrich groundwater for cooking could elevate the arsenic concentration in cooked rice (up to 129% above the raw sample), thereby enhancing the vulnerability of the rural population of West Bengal to arsenic exposure through rice consumption. The risk is heightened by the habit of drinking the stewed rice water (gruel) in the local communities. The cooking method employed, rice variety, background arsenic concentration in raw rice and cooking water arsenic concentration were found to be important predisposing factors that could affect the accumulation of arsenic in cooked form. The fundamental indigenous cooking practice followed by the villagers requires use of low-arsenic water for cooking as a necessary strategy to alleviate arsenic exposure in their staple food.
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Worldwide distribution of polyclyclicaromatic hydrocarbons in urban road dust.(International Journal of Environmental Science and Technology) (Majumdar, Deepanjan, Rajaram, B., Meshram, S., Suryawanshi, P., Rao, C. V. C. ,142,,397-420,Year : 2018)
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Polycyclic aromatic hydrocarbons (PAHs) is considered as one of the most important groups of organic environmental contaminants due to their toxicity, persistence and ubiquity. PAHs have been monitored in urban road dust at various locations worldwide in about last three decades. Resuspension of road dust containing PAHs is an important route of PAHs exposure to humans. This paper collates the available information on reported concentrations of PAHs in urban road dust at various locations worldwide classified as industrial, residential, traffic, city and commercial and other areas, reported sources of PAHs in urban road dust and related interpretations. Also, available information has been reviewed and documented country-wise. Variation in PAHs concentrations over various worldwide locations have been scrutinized and interestingly, most of the reported average PAHs concentrations were found to be distributed within a very narrow range of values, implying only little variation in average PAH concentrations in spite of great distances between locations, climatic variation and differences in anthropogenic activity.
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Managing future air quality in megacities : A case study for Delhi (Atomspheric Environment) (Amann, M., Purohit, P., Bhanarkar, A.D., Bertok , I., Borken - Kleefeld, J., Cofala, J., Majumdar , D., Nguyen, B., Rafaj, R., Schopp, W., Srivastava, A.,Vardhan, B.H.,161,,99-111,Year : 2017)
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"Urbanization, population and economic growth in Indian megacities like Delhi have resulted in an increase in energy and transportation demand leading to severe air pollution and related health impacts, as well as to the rapid growth in the greenhouse gas emissions. In this study, an integrated assessment of air quality and climate policies for Indian cities –with a particular focuson National Capital Territory of Delhi,has been carried out.We have developed emission inventory of air pollutants and greenhouse gases for the base year (2010) and evaluated the impact ofcurrent policieson emission projections by 2030 in the business-as-usual scenario. Emissions of coarse and neparticulate matter areprojected to be 51% and 15% higher in 2030 as compared to present. As the current legislations do not indicate progress towards the achievement of the Indian National Ambient Air Quality Standards in Delhi, we explored the efectiveness of additional emission control strategies with either advanced end-of-pipe emission controls or low carbon policies. Relative to the baseline scenario, the set of alternative policy strategies would reduce emissions rapidly in 2030.The results revealed that air quality policies under various scenarios could also have co-benefits of reducing carbon emissions. At the same time, the results suggest that low carbon policies would be more eficient to cut emissions as compared to advanced end-of-pipe emission control policies. However, their implementation could be limited by the availability of clean fuels. In the climate policy scenario, carbon emission in 2030 is estimated to decrease by 19% relative to baseline. Additional controls combined with low carbon policies like controlling non-industrial emissions create an opportunity to further enhance the scope for co-bene?ts and to attain the air quality standards in Delhi. "
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Synthesis, Spectral Properties and DFT Calculations of new Ruthenium (II) polypyridyl Complexes; DNA Binding Affinity and in Vitro Cytotoxicity Activity(Journal of Fluorescence) (Mallepally, R.R., Chintakuntla, N., Putta, V.R., K, N., Vuradi, R.K., P,M., S, S.S., Chitumalla, R.K., Jang J.,Penumaka, N., Sirasani, S. ,27 (4),,1513-1530,Year : 2017)
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In this paper a novel ligand debip (2–(4–N,N–diethylbenzenamine)1H–imidazo[4,5–f] [1, 10]phenanthroline) and its Ru(II) polypyridyl complexes [Ru(L)2(debip)]2+, (L = phen (1), bpy (2) and dmb (3)) have been synthesized and characterized by spectroscopic techniques. The DNA binding studies for all these complexes were examined by absorption, emission, quenching studies, viscosity measurements and cyclic voltammetry. The light switching properties of complexes 1–3 have been evaluated. Molecular docking, Density Functional Theory (DFT) and time dependent DFT calculations were performed. The Ru(II) complexes exhibited efficient photocleavage activity against pBR322 DNA upon irradiation and exhibited good antimicrobial activity. Also investigated 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay, lactate dehydrogenase (LDH) release assay and reactive oxygen species (ROS) against selected cancer cell lines (HeLa, PC3, Lancap, MCF-7 and MD-MBA 231).
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Polycyclic aromatic hydrocarbons over a tropical urbon and a high altitude Himalayan Station in India Temporal variation and source apportionment (Atomospheric Reserch) (Ray, D; Chatterjee,A; Majumdar,D; Ghosh,S.K; Raha.S,197,,331-341,Year : 2017)
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The temporal variations and major sources of polycyclic aromatic hydrocarbons (PAH) intrinsic to PM10 were investigated over a tropical urban atmosphere on the Indo-Gangetic Plain (IGP) and for the ?rst time over a high altitude urban atmosphere at eastern Himalaya in India. Samples were collected over Kolkata, a megacity and Darjeeling, a high altitude (2200 m asl) hill station in eastern India during the dry season (October 2015–May 2016). Fourteen PAHs were detected and quanti?ed over Kolkata and Darjeeling during three consecutive seasons, viz., post-monsoon, winter and pre-monsoon. The total-PAHs concentrations were in the order of winter (78.08–146.71 ngm?3) > post-monsoon (83.42–113.52 ngm?3) > pre-monsoon (37.65–109.27 ngm?3) at Kolkata, whereas post-monsoon (22.72–36.60 ngm?3) > winter (8.52–28.43 ngm?3) > pre-monsoon (5.45–13.34 ngm?3) at Darjeeling. The observed seasonality of PAHs at Kolkata vis-a-vis Darjeeling has been explored in the light of anthropogenic activities, boundary layer dynamics and meteorological parameters such as temperature, relative humidity, wind speed and solar radiation. Negative correlation was observed between total-PAHs and temperature, wind speed and solar radiation over Kolkata and Darjeeling. The positive matrix factorization (PMF) model calculations suggested that coal (26%), petrol (24%) and diesel (17%) combustion, commercial and household kitchens (18%) and municipal solid waste incineration (15%) are the possible contributors to the PM10 associated PAHs over Kolkata whereas diesel (37%), commercial and household kitchens (23%), coal (21%) and petrol (20%) are the possible PM10 associated PAH sources over Darjeeling.
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Analyric Techniques used to Detect DNA Binding Modes of Ruthenium(II) Complexes with Extended Phenthroline Ring (Journal of Fluorescence) (Devi, C.S; Thulasirm, B; Satyanarayana, S; Nagababu,P.
,,,2119-2130,Year : 2017)
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This review describes the analytical techniques used to detect DNA-probes such as Ru(II) complexes with hetero cyclic imidazo phenanthroline (IP) ligands. Studies on drug-DNA interactions are useful biochemical techniques for visualization of DNA both in vitro and in vivo. The interactions of small molecules that binds to DNA are mainly classified into two major classes, one involving covalent binding and another non-covalent binding. Covalent binding in DNA can be irreversible and may leads to inhibition of all DNA processes which subsequently leads to cell death. Usually, covalent interactions leads to permanent changes in the structure of nucleic acids. The non-covalent interaction of molecules with DNA can be due to electrostatic interaction, intercalation and groove binding. These interactions of DNA probes can be explored by various spectroscopic techniques viz. UV-visible, emission, emission quenching spectroscopy, viscosity and thermal denaturation measurements.
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How the Atmosphere over Eastern Himalaya, India is Polluted with Carbonyl Compounds? Temporal Variability and Identification of Sources(Aerosol and Air Quality Research) (,,,,Year : 2017)
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A study was conducted on atmospheric carbonyl compounds for the first time over a Himalayan atmosphere in India. Samples were collected from a high altitude hill station, Darjeeling (27.01°N, 88.15°E, 2200 masl) during June 2012 to May 2013. Temporal variation, meteorological influence, source apportionment and ozone formation potential etc were studied for acetaldehyde, formaldehyde, acetone, butanaldehyde, propanaldehyde, benzaldehyde, crotonaldehyde, valeraldehyde, isovaleraldehyde, hexanaldehyde, p-tolualdehyde and o-tolualdehyde. High concentration of Acetone (81.6 ± 63.5 μg m–3) was observed which could be due to the higher photochemical production from its precursor volatile organic compounds emitted from tea plants and tea processing units. The concentration of acetaldehyde (20.7 ± 47.6 μg m–3) and formaldehyde (11.6 ± 16.3 μg m–3) were found to be comparable with metro cities of India and world. The average annual concentration of total carbonyl compounds was 174.2 ± 184.6 μg m–3 with maximum during postmonsoon (456.9 ± 199.5 μg m–3) and minimum during winter season (72.2 ± 42.9 μg m–3). Meteorological parameters like temperature and surface reaching solar radiative flux played the major roles for the seasonal variation of the carbonyl concentration over the hill station. The average ratio of formaldehyde to acetaldehyde over Darjeeling was found to be 1.64 ± 1.43 well representing a typical urban atmosphere at this part of Himalaya. Positive matrix factorization model showed that the biogenic emissions from tea plants and vehicular emissions were the major sources of carbonyl compounds over the hill station.
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The genetic influence in fluorosis(Environmental Toxicology and Pharmacology) (Sreemanta Pramanik, Depanwita Saha (Corresponding Author),56,,157-162 ,Year : 2017)
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Fluorosis, caused by ingestion of excess fluoride, is endemic in at least 25 countries across the globe, China and India being the worst affected among them. Dental, skeletal and non-skeletal are the major types of fluorosis affecting millions of people in these countries. A number of genetic epidemiological studies carried out by investigators have shown the evidence for association between genetic polymorphisms in candidate genes and differences in the susceptibility pattern of different types of fluorosis among individuals living in the same community and having the same environmental exposure. These studies have pointed out that genetic variants in some candidate genes like COL1A2 (Collagen type 1 alpha 2), CTR (Calcitonin receptor gene), ESR (Estrogen receptor), COMT (Catechol-o-methyltransferase), GSTP1 (Glutathione S-transferase pi 1), MMP-2 (Matrix metallopeptidase 2), PRL (Prolactin), VDR (Vitamin D receptor) and MPO (Myeloperoxidase) could increase or decrease the risk of fluorosis among the exposed individuals in endemic areas. So, it is increasingly becoming evident that an individual's genetic background could play a major role in influencing the risk to fluorosis when other factors like specific environmental exposures including dietary patterns of fluoride intake and other nutrients remain the same. The current manuscript presents an up-to-date critical review on fluorosis, focusing mainly on the genetic association studies that have looked at the possible involvement of genetic factors in fluorosis.
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Nutrient and enzyme mobilization in earthworm casts: A comparative study with addition of selective amendments in undisturbed and agricultural soils of a mountain ecosystem(International Biodeterioration & Biodegradation) (Pooja Singh, Sudip Mitra, Deepanjan Majumdar, Pradip Bhattacharyya, Amit Prakash, Pallabi Borah, Ankita Paul, Latha Rangan,119,,437-447,Year : 2017)
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Earthworms are known to bio-degrade various types of organic materials added or already present in soil. Two soils were collected from different land use patterns viz. an agricultural land (AL) and an undisturbed land (UL) of a mountain ecosystem of State of Himachal Pradesh in India for the present investigation. A laboratory microcosm study was carried out to elucidate effects of various agricultural soil amendments, viz. wood ash (WA), rice husk (RH), cow dung (CW) and their mixture (MA) applied @25 t ha_1, on selective biological and chemical properties of earthworm (Eisenia fetida) casts and growth in the collected soils. Subsequently, earthworms were reared in soils from both AL & UL, treated with the amendments; and the resultant earthworm cast (EwC) properties were found to be largely determined by the nature of amendments rather than land use types. Soils treated with MA produced casts displayed higher nutrient content, microbial biomass C with higher activities of dehydrogenase and urease. Earthworm growth and cast formation were greater in the soil from UL over soil from AL for all treatments except WA, implying better acclimatization and earthworm activity in the former. Further, casts produced under UL had higher nutrient mobilization and enzyme activity in comparison to AL. Results suggested that agricultural intervention in an undisturbed land might weaken its ability to support growth, development in conjunction with the activities of earthworms and associated enzymes.
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Polycyclic aromatic hydrocarbons and metals in mosquito coil and coilash: are the concentrations alarming(International Journal of Environment and Pollution) (Majumdar, Deepanjan, Maske, N., Kamal, N.
,611,,46-63,Year : 2017)
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Unmanaged mosquito coil ash could be regarded as a possible source of metal and PAH contamination in households but such risk is generally overlooked. Therefore, to address this issue, polycyclic Aromatic Hydrocarbons (PAHs) and metals were estimated in the ash generated by a few popular mosquito coils marketed in India. The detected concentration range of PAHs in coil ash samples was 8 (Benz(a) anthracene) to 2925 ng g-1 ash (Phenanthrene) while metal concentration ranged from 0.1 (Cd) to 28366 µg g-1 ash (Fe). In the coil base material, concentration of metals ranged from 0.1 (cd) to 3193.0 (Fe) µg g-1 coil powder, indicating substantial magnification of metal concentration in coil ash over coil base material. The study indicated that mosquito coil ash could be an important source of metal and PAH contamination in households and hence should be carefully managed.
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Inter-seasonal and spatial distribution of ground-level greenhouse gases(CO2, CH4, N2O) over Nagpur in India and their management roadmap(Environmental Monitoring andAssessment) (Majumdar, Deepanjan, Rao, P., Maske, N.,189(3),,121,Year : 2017)
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Ground level concentrations of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) were monitored over three seasons i.e. post-monsoon (September-October), winter (January-February) and summer (May-June) for 1 year during 2013-2014 in Nagpur city in India. The selected gases had low to moderate variation both spatially (residential, commercial, traffic intersections, residential cum commercial sites) and temporally (at 7:00, 13:00; 18:00 and 23:00 h in all three seasons). Concentrations of gases were randomly distributed diurnally over city in all seasons and there was no specific increasing or decreasing trend with time in a day. Average CO2 and N2O concentrations in winter were higher over post-monsoon and summer while CH4 had highest average concentration in summer. Observed concentrations of CO2 were predominantly above global average of 400 ppmv while N2O and CH4 concentrations frequently dropped down below global average of 327 ppbv and 1.8 ppmv, respectively. Two tailed Student’s ‘t’ test indicated that post-monsoon CO2 concentrations were statistically different from summer but not so from winter while difference between summer and winter concentrations was statistically significant (P<0.05). CH4 concentrations in all seasons were statistically at par to each other. In case of N2O, concentrations in post-monsoon were statistically different from summer but not so from winter, while difference between summer and winter concentrations was statistically significant (P<0.05). Average ground level concentrations of the gases calculated for 3 seasons together were higher in commercial areas. Environmental management priorities vis a vis greenhouse gas emissions in the city are also discussed.
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Characterization of polycyclic aromatic hydrocarbons in fugitive PM10 emissions from an integrated iron and steel plant(Science of the Total Environment) (V.V. Khaparde, A.D. Bhanarkar, Deepanjan Majumdar, C.V. Chalapati Rao,562 (2016) ,,155–163,Year : 2016)
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Fugitive emissions of PM10 (particles b10 ?m in diameter) and associated polycyclic aromatic hydrocarbons (PAHs) were monitored in the vicinity of coking unit, sintering unit, blast furnace and steel manufacturing unit in an integrated iron and steel plant situated in India. Concentrations of PM10, PM10-bound total PAHs, benzo (a) pyrene, carcinogenic PAHs and combustion PAHs were found to be highest around the sintering unit. Concentrations of 3-ring and 4-ring PAHs were recorded to be highest in the coking unit whereas 5-and 6-ring PAHs were found to be highest in other units. The following indicatory PAHs were identified: indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, benzo (k) fluoranthene in blast furnace unit; indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, chrysene in sintering unit; Anthracene, fluoranthene, chrysene in coking unit and acenaphthene, fluoranthene, fluorene in steel making unit. Total-BaP-TEQ (Total BaP toxic equivalent quotient) and BaP-MEQ (Total BaP mutagenic equivalent quotient) concentration levels ranged from 2.4 to 231.7 ng/m3 and 1.9 to 175.8 ng/m3, respectively. BaP and DbA (dibenzo (a,h) anthracene) contribution to total-BaP-TEQ was found to be the highest.
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DETERMINATION OF AIR CHANGE RATES BY USING INDOOR CO AS TRACER: APPLICABILITY AND ENVIRONMENTAL ISSUES(Environmental Engineering and Management Journal) (Deepanjan Majumdar, Dinakar Patil, Raman Malviya, Jitendra Trivedi,15(2),,421-427,Year : 2016)
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Air change rates and ventilation of a room was determined by CO Tracer Decay Technique. The tracer was generated by burning bulk amount of mosquito coils, an easy and low cost method of CO generation. The temporal decay in CO concentration in indoor air under closed and open room conditions were determined by collecting indoor air periodically at a few minutes interval in Tedler Bags and analyzing the same for CO. The air changes rate per hour (ACH) was calculated from the temporal decline of indoor CO concentration in indoor air. The study indicated that CO generated by a low cost and easily applicable method like combustion of organic materials could be used as a tracer to determine ACH and ventilation rate. Background CO in air could be suitably used for ventilation studies in rural/urban slum dwellings in India and many other countries where substantial CO is found indoors due to combustion of biomass, incense sticks and mosquito coils.
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Inhalation exposure or body burden? Better way of estimating risk - an application of PBPK model(Environmental Toxicology and Pharmacology) (Dipanjali Majumdar; Chirasree Dutta; Subha Sen.,41 ,,54–61,Year : 2016)
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We aim to establish a new way for estimating the risk from internal dose or body burden due to exposureof benzene in human subject utilizing physiologically based pharmacokinetic (PBPK) model. We alsointend to verify its applicability on human subjects exposed to different levels of benzene. We estimatedpersonal inhalation exposure of benzene for two occupational groups namely petrol pump workers andcar drivers with respect to a control group, only environmentally exposed.Benzene in personal air was pre-concentrated on charcoal followed by chemical desorption and anal-ysis by gas chromatography equipped with flame ionization detector (GC-FID). We selected urinarytrans,trans-muconic acid (t,t-MA) as biomarker of benzene exposure and measured its concentrationusing solid phase extraction followed by high performance liquid chromatography (HPLC).Our estimated inhalation exposure of benzene was 137.5, 97.9 and 38.7 g/m3for petrol pump workers,car drivers and environmentally exposed control groups respectively which resulted in urinary t,t-MAlevels of 145.4 ± 55.3, 112.6 ± 63.5 and 60.0 ± 34.9 g g−1of creatinine, for the groups in the same order.We deduced a derivation for estimation of body burden from urinary metabolite concentration usingPBPK model. Estimation of the internal dose or body burden of benzene in human subject has beenmade for the first time by the measurement of t,t-MA as a urinary metabolite using physiologically basedpharmacokinetic (PBPK) model as a tool. The weight adjusted total body burden of benzene was estimatedto be 17.6, 11.1 and 5.0 g kg−1of body weight for petrol pump workers, drivers and the environmentallyexposed control group, respectively using this method. We computed the carcinogenic risk using boththe estimated internal benzene body burden and external exposure values using conventional method.Our study result shows that internal dose or body burden is not proportional to level of exposure ratherhave a non-linear relationship. At a higher exposure level such as for occupational exposure of petrolpump workers and drivers, the conventionally estimated risk is higher than risk estimated from internalbody burden. Likewise, for environmental exposure the conventional risk estimation predict lower levelthan estimated in our study. This emphasizes the importance of body burden and to consider it as a keyparameter while estimating health risk at varying level of exposure.
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Characterization of Bioaerosols and their Relation with OC, EC and Carbonyl VOCs at a Busy Roadside Restaurants-Cluster in New Delhi.(Aerosol and Air Quality Research) (Smita Agarwal, Papiya Mandal, Dipanjali Majumdar, Shankar G. Aggarwal, Anjali Srivastava,16,,3198–3211,Year : 2016)
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Measurement of biological particles (bioaerosols) in ambient air is of great importance as it is directly linked with the health issues. However, data on the bioaerosols characterization are scarce. Here we report on the concentration and characterization of bioaerosols (including bacterial and fungal aerosols) as well as determination of organic and elemental carbon (OC and EC) in total suspended particulate matter (TSPM) at a busy roadside restaurants-cluster site in New Delhi. In addition, 14 carbonyl volatile organic compounds (carbonyl VOCs) were also measured and their relationship with bioaerosols and OC/EC is assessed. The culturable airborne bacterial and fungal concentrations (CAB and CAF) at restaurant area varied significantly in different seasons ranging from 1.7 × 104–9.8 × 104 (averaged 6.3 × 104 ± 2.6 × 104 cfu m–3) and 3.5 × 102–9.5 × 103 (3.9 × 103 ± 3.1 × 103 cfu m–3) cfu m–3, respectively. Major concentration peaks of TSPM, OC, EC as well as bacterial and fungal aerosols were found in winter and spring seasons. These peaks can be attributed to the low atmospheric boundary layer (ABL) height and favourable meteorological conditions for microbial growth in winter and spring seasons in New Delhi. Good correlations (R2 > 0.5) were observed between CAB, CAF, TSPM and OC. On the other hand, CAB and CAF were not found to be correlated with carbonyl compounds (R2 < 0.2) indicative of their diverse sources. The bacterial identification was done by 16s rDNA sequencing and the identified strains were Bacillus sp., Bacillus firmus, Bacillus licheniformis, Bacillus cereus, Bacillus pumilus, Acinetobacter sp. and Acinetobactor radioresistens gene. Predominant fungal genera identified were Aspergillus, Cladosporium, Alternaria and Fusarium, which are known for adverse health effects causing numerous allergic and pathogenic inflammations.
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