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Metal molybdate-doped aluminium phosphate heterostructures have been prepared by a solid solution method and found to be photoluminescence, semiconducting properties and effective catalysts for the photoreduction of o-nitroaniline and p-nitroaniline.

In this work, we report the redox properties in organic catalytic transformation and antibacterial activity of novel Cu x Ag x Zn1-2x O nanocomposites. Cu- and Ag-doped ZnO [Cu x Ag x Zn1-2x O (x = 0.1)] (CAZ), Cu-doped ZnO [Cu x Zn1-x O (x = 0.1)] (CZ), and Ag-doped ZnO [Ag x Zn1-x O (x = 0.1)] (AZ) were prepared via a chemical co-precipitation method. The synthesized nanocomposites were characterized using different spectroscopic techniques. The catalytic activity of CAZ, CZ, and AZ was examined for the reduction of 4-nitrophenol (4-NP) and 4-nitroaniline (4-NA) in the presence of NaBH4 in an aqueous medium. The photocatalytic oxidation efficiency of these catalysts was also observed against naphthol orange (NO) under ultraviolet light. It was found that the catalytic reduction and oxidation efficiency of CAZ is higher than that of CZ and AZ in 4-NP/4-NA and NO in a water solvent, respectively. The antibacterial property of CAZ was also studied against Gram-positive and Gram-negative bacteria by agar well diffusion and the minimum inhibitory concentration methods. It was found that CAZ shows better antimicrobial activity compared to its parental Cu(NO3)2·3H2O, AgNO3, and ZnO. Therefore, the incorporation of Cu and Ag into ZnO increases its catalytic and antimicrobial activity remarkably. Fourier-transform infrared and X-ray diffraction (XRD) studies of CAZ indicate the incorporation of Cu and Ag into the lattice of ZnO. The phase structure of CAZ was wurtzite hexagonal, and the average crystallite size was 93 ± 1 nm measured from XRD. The average grain size and particle size of CAZ were found to be 200 and 100 ± 5 nm originating from SEM and transmission electron microscopy studies, respectively. The optical energy band gap of CAZ is 3.15 eV, which supports the excellent photocatalyst under UV light. CAZ also exhibits good agreement for photoluminescence properties with a high intensity peak at 571 nm, indicating surface oxygen vacancies and defects which might be responsible for higher photocatalytic activity compared to others. The nanocomposite shows excellent reusability without any significant loss of activity.

Effluents released from various industries and domestic sewage can contaminate the seawater leading to serious impacts on marine biota. The present study aims for the estimation of trace and toxic metals concentrations in different marine biota species collected from the Thane creek area, Mumbai, India. Among different metals analyzed, the highest and the least concentration was observed for Fe (9.0–118.3 mg/kg ww) and As (4.7 × 10−4–7.8 × 10−3 mg/kg ww), respectively in most of the marine biota. The toxic metal concentrations observed in the current study are less than the Food and Agriculture Organization (FAO, 1983/1987), World Health Organization (WHO, 1983/1987) limits given for Hg (2 mg/kg ww), Pb (0.5 mg/kg ww) and As (1 mg/kg ww). In the current study, Fe was found to have the highest bio-concentration factor followed by Cu and Zn. Crab has relatively higher bio-concentration factor for most of the metals (except for Se, Hg) as compared to fish samples analyzed. Se-health benefit values were found to be positive indicating less health effects due to Hg exposure from marine biota. The estimated hazard quotient (HQ) value was observed to be highest for Cu in crabs (5.6E-02). However, the Hazard Index (HI) values of all studied marine biota species are

Hemophagocytic Lymphohistiocytosis (HLH) is a rare and fatal entity in children with fever, organomegaly, cytopenias, liver dysfunction and coagulopathy and does not respond to conventional therapies. It is categorized into two types: Primary (inherited) and Secondary (associated with infection, malignancy, autoimmune diseases, etc.). Prognosis of primary HLH is poor, whereas in secondary HLH outcome depends upon the underlying disease. This study is a retrospective analysis of case records of children admitted with a diagnosis of HLH from January 2016 to December 2019 in the Pediatrics department of a teaching hospital in Odisha, India. It describes the clinical features, laboratory findings, diagnosis, treatment and outcome of children with HLH.Thirteen children were diagnosed as HLH for 36 months in the age range from 1 month 11 days to 14 years. Fever and splenomegaly were present in 100% of cases while hepatomegaly in 69.2% and rash in 15.3% of cases. Anaemia, hyperferritinemia were detected in 100% whereas neutropenia in 76.9% and thrombocytopenia in 38.4%. Bone marrow aspiration was done in 7 patients out of whom 6 revealed haemophagocytosis. Serum fibrinogen was low in 8 cases. Out of 13 cases, 7 patients received corticosteroid, and 3 of them also received Cyclosporine along with Steroids. Two cases left against medical advice, 7 had infectious aetiology, and 3 cases were diagnosed as Systemic onset Juvenile Idiopathic arthritis (SoJIA). Seven patients required ICU care. Ten cases recovered, and one died as HLH is a rare entity and has a high chance of fatality early diagnosis and prompt therapy results in a better outcome.

The groundwater samples were found to be contaminated with high concentrations of uranium (U) in Punjab state as well as in few other locations of India. U being chemically toxic can deteriorate health when ingested. Hence, there is a need to remove U from contaminated water using an efficient, cheap and user friendly method. A study was initiated to investigate the efficiency of low-cost adsorbents in removing U from water. Seven adsorbents were screened for U removal efficiency, among which fly ash (FA) and tea waste (TW) were found to have better removal efficiency. Solid–liquid contact time and solution pH were optimized to establish conditions for better U removal efficiency. The U adsorption on FA and TW followed pseudo-second-order kinetics with rate constant values 4.63 g/mg/min and 15.63 g/mg/min, respectively. FA and TW had the highest U removal capability at pH 6 and pH 4, respectively. The U sorption data were fitted with Freundlich and Dubinin–Radushkevich isotherm models. The U adsorption on FA and TW is found to be a physical process with mean free energy (E) values less than 8 kJ/mol. Theoretically calculated maximum adsorption capacity values indicate that FA is a better adsorbent as compared to TW, which has been further confirmed experimentally. The U adsorption on both the adsorbents has interference from Ca2+ and no interference from Fe3+ at tested U concentrations. It is also found that FA and TW are effective in decontaminating U from spiked real groundwater samples to below the WHO (Guidelines for drinking water quality, 4th ed, vol 1, World Health Organization, Geneva, 2011) limit.

The green synthesis of copper nanoparticles (CuNPs) using a leaf extract from Jatropha curcas (JC) has been documented in our present research work. The existence of flavonoids, tannins, glycosides, and alkaloids was confirmed by the phytochemical analysis of the plant extract and these chemicals can be used as reducing, stabilizing and capping agents. After six months, the JC-CuNPs were found to be stable without any evidence of agglomeration. The JC-CuNPs were characterised by XRD, FT-IR, SEM, TEM and UV-vis spectrophotometry. The average particle and crystal sizes of the JC-CuNPs were found to be 10 ± 1 and 12 ± 1 nm, respectively. The SPR peaks were found at 266 and 337 nm, measured using electronic spectroscopy, and the calculated optical band gap was found to be 3.6 eV at 337 nm, indicating the semiconductor behaviour of the JC-CuNPs. JC-CuNPs have potential photocatalytic activity against methylene blue (MB) compared with other dyes in the presence of sunlight and the rate constant (k) value is 2.30 × 10−4 s−1. The JC-CuNPs also have a binding property with CT-DNA through an intercalation mode and the binding constant (Kb) is 1.024 × 102 M−1.

In the present study, the influence of coal fly ash's particle size on uranium (U) decontamination from water samples is investigated. Accordingly, fly ash is segregated into five different size fractions (i.e., 63–90 μm, 125 μm) using an electromagnetic sieve shaker. Adsorption experiments are carried out in triplicate samples (for equilibration time at pH 6) using a laboratory batch method on all the size fractions with known U concentration. The highest U adsorption is observed for the lowest size fraction (i.e.

Background and aim Nephrotic syndrome is one of the commonest glomerular diseases in children, and the majority of them have minimal change lesions in histology with a favorable outcome. Most children with minimal change disease (MCD) are steroid-sensitive, but half of them have a frequent relapse and a prolonged course. This study was conducted to evaluate the clinical manifestations and biochemical profile and to determine independent risk factors of frequent relapse in children with steroid-sensitive nephrotic syndrome (SSNS). Methods This was a tertiary care hospital-based observational study conducted at the pediatric department of Kalinga Institute of Medical Sciences (KIMS), Bhubaneswar, India, from October 2017 to September 2019. Fifty-three children from age one to 15 years admitted with steroid-sensitive nephrotic syndrome diagnosed as per the International Study of Kidney Disease in Children (ISKDC) criteria were enrolled in the study. On admission, history-taking, physical examination, and routine hematological and biochemical tests were carried out. Children who had no infection were started oral prednisolone at the dose of 2 mg/kg/day for six weeks, followed by 1.5 mg/kg/day on alternate days for six weeks with daily follow-up for evidence of proteinuria till remission. The parameters evaluated were age at presentation, sex, type of presentation, precipitating factors, laboratory findings, and rapidity of steroid response. All children were followed up for one year, and those with no relapse over a period of one year after remission served as the control group to determine the risk factors for relapse. Data were analyzed using standard statistical software (Stata version 13.1, StataCorp LLC, College Station, Texas, USA). Results Of the 53 cases, 47% of the children had a relapse. In the relapse category, 88% were male, and 67% were between one and 5.5 years. The clinical manifestations during the first episode in the relapse group were similar to the no relapse group. Investigations revealed that 64% of the children with relapse had serum total protein ≤ 4.2 g/dL (p = 0) and that 59% had serum albumin ≤ 1.8 g/dL (p = 0.004). In the relapse group, 41% of the children went into remission within two weeks of initiation of therapy as compared with 80% in the no relapse group. Conclusion The risk factors determined for relapse in SSNS are male sex, younger age, low serum albumin, low serum total protein, and delayed response to steroid therapy.

The current work employs silicon-based one dimensional photonic structure which delivers ‘20’ different types of monochromatic beams (wavelengths) via filtering action. The I/P signals are essentially varies from visible to short infrared range to justify the work. Though similar type of works related to filtering application are found in the literature, the present research deals with an output signal which could be deployed in different purposes vis-à-vis dentistry, dermatology, spectroscopy, printing, holography, barcode scanning etc. The physicality of this work incorporates 68 layers of silicon monoxide and silicon based one-dimensional optical waveguide along with their configuration where the plane wave expansion method does fulfill the nitty-gritty of required mathematics to solve out electromagnetic wave equations. Reflectance and transmittance characteristics along with the absorbance are the critical parameters that substantiate the said application.

Introduction The allergic sensitization in childhood asthma is common and the prevalence varies in different geographical locations. The data on allergen sensitization to guide clinicians on allergy avoidance is limited. Method This prospective observational study was conducted between October 2019 and April 2020 on children aged two to 14 years attending an outpatient clinic. Those with recurrent wheezing or physician-diagnosed asthma were interviewed; eosinophil count, total serum immunoglobulin E (IgE) was measured; and skin prick test (SPT) was done using standardized reagents. Wheal size of ≥3mm was considered positive. Results A total of 80 children were enrolled. The mean age was 71.15 ± 33.52 months (M:F ratio =1.96:1). Allergic rhinitis, conjunctivitis, and dermatosis were seen in 76 (95.0%), 33 (41.3%), and 22 (27.5%) cases, respectively. The mean absolute eosinophil count was 576 ± 427per cmm. The mean total IgE was 800.9 ± 883.2IU/ml. Seasonal and diurnal variations were found in 34 (42.5%) and 79 (98.8%) cases. Out of 1753 skin pricks using 27 reagents, 355 (20.25%) were positive. Increasing age was significantly associated with increasing SPT positivity (P = 0.0001). The most common sensitive aeroallergens were Kentucky bluegrass (25%), Dermatophagoides pteronyssinus (22.5%), Dermatophagoides farinae (21.3%), Timothy grass, and Alternaria alternans (20% each). The most common sensitive food allergens were spinach (25%), banana (22.5%), carp (20%), shrimp and hen’s egg (18.8% each), and cow’s milk (17.5%). Conclusion Increasing age was associated with increasing SPT positivity in childhood asthma. The most common sensitive aeroallergens were Kentucky bluegrass and Dermatophagoides pteronyssinus; spinach and banana were the most common food allergen.

To study manifestations and outcome of scrub typhus in infants. Case record analysis of infants with scrub typhus admitted to a tertiary care hospital, diagnosed by IgM ELISA from January 1, 2016 to December 31, 2019. Out of 374 children diagnosed with scrub typhus, 34 (9%) were infants. Chief presentation were fever 34 (100 %), feeding difficulty 24 (70.6%), lethargy 18 (52.9%) and irritability 15 (44.1%). Clinically, pallor 30 (88.2%), tachycardia 29 (85.3%), tachypnea 24 (70.6%), hepatosplenomegaly 30 (88.2%) and eschar 6 (17.6%) were detected. Significant laboratory parameters were anemia 33 (97.1%), leukocytosis 33 (97.1%), thrombocytopenia 17 (50%) and transaminitis 21 (63.6%). Pneumonia 18 (52.9%) was noticed as the major complication. Infants requiring intensive care 17(50%) had characteristic thrombocytopenia, hypoalbuminemia and transaminitis (P

Background Enteric fever is a major health problem in developing countries. Varied clinical presentation leads to diagnostic dilemmas resulting in fatal complications. Objective To determine the socio-demographic, clinical manifestations, complications, antibiotic sensitivity pattern, treatment, and outcome in hospitalized enteric fever patients. Methods A retrospective case record analysis of hospitalized patients in the age group one to 14 years with a discharge diagnosis of enteric fever was done in a tertiary care centre of Odisha over a period of three years (January 2017 to December 2019). Results Of 112 patients, 75% of children belonged to the six to 14 years age group with a mean age of 7.6 +/- 3.6 years and a male to female ratio of 1.66:1. The peak of cases was seen during the month of January to June with 94% of cases occurring in low and middle socioeconomic status. The commonest presentation was fever in 98.21%; other features were vomiting (39.29%), pain in abdomen (21.43%), diarrhoea (26.79%), and anorexia (14.29%). Eosinopenia was found in 58.93%, transaminitis in 30.36%, and raised CRP in 73.21%. In 30 children blood culture was positive with sensitivity to third-generation cephalosporin. All isolates were nalidixic acid-resistant Salmonella Typhi (NARST). Complications were seen in 21.42%. All recovered and two left against medical advice. Conclusion Enteric fever is a major threat in the paediatric age group. Early clinical diagnosis with rational use of antibiotics according to sensitivity pattern is important. Improved hygiene, vaccination, and awareness among people is necessary for prevention.

Objective: To study factors that influence the age of discharge of very low birth weight (VLBW) preterm neonates from the Neonatal Intensive Care Unit (NICU). Setting: This cohort study was conducted in the NICU, Department of Pediatrics, Kalinga Institute of Medical Sciences, Bhubaneswar, India, from April 2019 to December 2019. Patients: Neonates whose birth weight was

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder due to uncontrolled activation of macrophage and cytokine release, which can be due to either genetic causes (familial) or secondary to infections malignancy and other less common cause. Parvovirus B19 rarely causes HLH. Diagnosing HLH in sickle cell disease, which inherently has high ferritin levels and pancytopenia, is particularly challenging. We are reporting HLH as a complication with parvovirus B19 infection in the background of sickle beta-thalassemia. Based on our search of available medical literature, this is the first case of HLH complicating parvovirus B19 infection in a pediatric age group with sickle beta-thalassemia.

Nanomaterials and Crystal Design Laboratory, Department of Chemistry, Indira Gandhi National Tribal University, Amarkantak-484 887, Madhya Pradesh, India E-mail: tanmay.ghorai@igntu.ac.in/tanmayghorai66@gmail.com Manuscript received online 02 July 2020, accepted 29 August 2020 Green synthesis has been adopted for the synthesis of Cu based ZrO2 nanoparticles via the co-precipitation method. Differ­ent mole percentage of copper was incorporated in zirconia and prepare various Cu2xZr1-xO2 (x = 0.05, 0.1, 0.2, 0.3, 0.4) nanoparticles. Among all the compositions Cu2xZr1-xO2 (x = 0.05) (CZ) exhibits higher photocatalytic activity compare to pure ZrO2 and other compositions for degradation of naphthyl orange (NO) under visible light in the aqueous medium. Most inter­esting that the mol% of Cu2+ ion in the mother composition is increased, the degradation rate of NO is decreased but CZ takes only 45 min to decolourize NO completely. The comparative study was also investigated in various model dyes like methyl orange (MO), methyl red (MR), rhodamine B (RhB) including NO in presence of catalysts and oxidation of NO spectra was recorded at constant time interval. CZ nanoparticles were characterized by a host of different techniques such as X-ray dif­fraction, FTIR, SEM and UV-Visible spectroscopy. The phase structure of Cu2xZr1-xO2 was cubic and crystallite sizes was found to be 17±1 nm, which was also compatibility from grain sizes of nanoparticles 20±1 nm (SEM analysis). The band gap of Cu2xZr1-xO2 is 5.03 eV calculated from the optical measurement.

We report the direct observation of the light absorption enhancement effect due to the mixing of black carbon (BC) and organic carbon (OC) aerosols generated during biomass combustion. The biomass fuels viz. mango tree wood (Mangifera indica) and dung cake were burned and the dry absorption of the aerosol stream was measured using the 7-wavelength aethalometer. The absorption coefficients were measured for thermally denuded and undenuded aerosols. The measurements provided an enhancement ratio for black carbon in presence of organic carbon at seven different wavelengths. The near-source enhancement ratio for wood and dung cake at 880 nm was found to be 1.35 ± 0.06 and 1.59 ± 0.08, respectively. The enhancement effect was found to increase with the decrease in wavelength for both the fuels, indicating absorption by the brown carbon. The organic coating on the black carbon was estimated using the mie theory modelling. The organic coating factor on the black carbon was found to be 1.37 and 1.69 for wood and dung cake, respectively. The enhancement ratio at 370 nm increased with the increase in the absorption angstrom exponent (AAE). The enhancement ratio depicted negative linear dependence (r = −0.91) on the logarithmic ratio of black carbon and absorption coefficients of brown carbon at 370 nm across both fuels and burn conditions.

Size fractionated mainstream cigarette smoke (MCS) samples were collected with variable configuration cascade impactor (VCCI). Samples were extracted ultrasonically and analysis of sixteen priority polycyclic aromatic hydrocarbons (PAHs) was performed using high performance liquid chromatography (HPLC) coupled with UV-visible detector. Identification of PAHs were also carried out using gas chromatography coupled with mass spectrometry (GC-MS) technique. Data of size fractionate PAHs in MCS were used to calculate size dependent deposition in different compartment of human respiratory tract using multiple path particle dosimetry (MPPD) model. All brand cigarette smoke showed similar trends of particle mass and PAHs size distribution peaked at two sizes 0.3–0.1 µm and 0.75–1.13 µm aerodynamic diameter. All tested brands of MCS recorded around 48.75% of two and three-ring PAHs, 23 to 25% four-ring PAHs and 26–27% five and higher rings PAHs of total analyzed PAHs. Benzo[a]pyrene equivalent (B[a]Peq) PAHs emission in MCS was found to be 110 ± 12 (µ ± 1σ) ng per cigarette for tested brands. Total deposition fraction in respiratory tract was found to be 0.69 ± 0.26 for tested size ranges. Average 5th and 95th percentile values of incremental lifetime cancer risk (ILCR) for smoker due to PAHs exposure were found to be 1.3 × 10–5 to 3.9 × 10–5 respectively for tested cigarette brands.

In the present study, particulate matter (PM10) was collected from two different locations viz. Jogannapalem and Parawada sites of Visakhapatnam. During study period, PM10 concentrations were found in the range from 34.8 to 109.7 μg/m3 and from 32.3 to 137.3 μg/m3 at Jogannapalem and Parawada sites respectively. Chemical characterization of PM10 was carried out to estimate the concentration levels of various particle bound chemical species (Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Pb, Cd, Cl−, F-, NO3-, SO42−, Na+, K+, Mg2+ and Ca2+). Among different species, Al was observed to have highest average concentration (4.1 μg/m3 at Jogannapalem and 3.8 μg/m3 at Parawada) at both the sampling sites followed by K at Jogannapalem and Ca at Parawada. PM10 concentration as well as trace metals concentration (except Mn and Fe) was observed to have higher concentrations at Parawada site as compared to Jogannapalem site, indicating higher pollution at Parawada. Source apportionment study carried out using PMF (USEPA PMF5.0) receptor model identified six major sources at Jogannapalem and seven predominant sources at Parawada, which are contributing to collected PM. The two study locations share five common sources viz. crustal, sea salt spray, coal combustion, fuel oil combustion and metal industry. The other sources include biomass burning at Jogannapalem; road traffic and secondary aerosols at Parawada. At Jogannapalem, biomass burning (35%) is the predominant source, whereas coal combustion (22.6%) is dominating at Parawada. PMF factor profiles were observed to have similar elemental profiles obtained at different industrial locations of Visakhapatnam.

A study was undertaken to evaluate the radiation doses arising from a dwelling built using fly ash as one of the components of the concrete in different proportions. The radioactivity contents of the fly ash samples were determined and doses to occupants were calculated assuming different scenarios. The internal dose in an office and home were in the range of 0.028 to 0.049 mSv year-1 and 0.099 to 0.17 mSv year-1 , respectively. The external doses ranged between 0.046 and 0.21 mSv year-1 in the office and 0.1 and 0.69 mSv year-1 in the home. The cumulative dose from the use of fly ash as a building material ranged from 0.074 to 0.26 mSv year-1 in the office and 0.2 to 0.86 mSv year-1 in the home.

Firewood, coal, dung cake, kerosene and Liquefied Petroleum Gas (LPG) are the most commonly used fuels for cooking and heating purposes in developing countries. Combustion of such fuels leads to high concentrations of pollutants in the indoor environment. Polycyclic aromatic hydrocarbons (PAHs) are emitted during residential combustion, and have carcinogenic and genotoxic properties. In this study, data from an experimental setup for estimation of emission rate of particulate-bound PAHs generated during combustion of such fuels are used. PAHs emission rates were used in a probabilistic single box model for prediction of time average particle associated indoor B(a)P equivalent (B(a)Peq) concentrations of PAHs resulting from typical Indian cooking. Model parameters such as fuel consumption rate, stove power and cooking time were also evaluated experimentally. Particle bound B(a)Peq PAH emission factor was found to be highest (0.96 mg kg−1) for dung cake, and lowest for LPG (0.48 mg kg−1) among tested fuels. The time averaged B(a)P equivalent concentrations in indoor environment were found to be 0.82, 0.45, 0.87, 0.30, and 0.14 μg m−3 for firewood, coal, dung cake, kerosene and LPG respectively. Results reveal that there was higher B(a)P equivalent concentration during combustion of biomass (dung cake, fire wood) as compared to fossil fuels (coal) and non-solid fuels (kerosene, LPG). Predicted time averaged indoor air B(a)Peq concentrations of PAHs were found to be much higher than the WHO indoor air guideline values for all tested fuels.

The goal of the study is to investigate elemental concentrations and source signatures of particulate matter at a selected receptor site in an urban area Navi Mumbai which is one of the hot spots of India with heavy industrialization. To achieve the objective, particulate matter samples were collected from 2008-2010 using Gent sampler with the automatic dichotomous size segregation unit. It was observed that the three year average concentrations of coarse ((PM_(10-2.5μm)) and fine (PM_(2.5μm)) fractions of PM were 89.92 (μg m^(-3)) and 42.25 (μg m^(-3)) respectively which were higher than the national standards prescribed by Central Pollution Control Board (CPCB), India. Subsequent elemental analysis of air filters using INAA and EDXRF showed marginally higher levels of anthropogenic derived elements. Furthermore, in the present study potentially contributing sources of coarse and fine PM were identified using two different receptor model techniques Factor Analysis (FA) and Positive Matrix Factorization (PMF). Six possible contributing sources of coarse fraction and seven probable sources of fine PM were identified by both the techniques. Further, sources identified by the receptor techniques and the comparability between the two techniques were also evaluated.

Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is a fatal illness manifested by fever, morbilliform rash, multi systemic involvement and eosinophilic leucocytosis with about 10% mortality. Authors report DRESS syndrome in an adolescent girl due to anti-depressant and anti-psychotic which improved dramatically after withdrawal of offending drugs and starting of steroids

The present study provides an estimation of the site-specific distribution coefficient for radium around a uranium mining site. The soil parameters which affect the Kd value of radium were also estimated. For the estimation of the distribution coefficient of radium the equilibration time was optimized. The distribution coefficient of radium was determined using the laboratory batch method. The distribution coefficient of radium varies from 796 ± 9 mL g-1 to 2,285 ± 52 mL g-1 . Kd values of radium were observed to be higher for one-meter-depth soil samples compared with top soil samples in all the sampling locations. It was found that the Kd of radium strongly depends on different soil parameters such as pH, organic matter (OM) and cation exchange capacity (CEC). With increasing soil pH, OM and CEC, the Kd of radium increases linearly.

The typical mixtures of polycyclic aromatic hydrocarbons are established as lung carcinogens, but their exposure and associated risk from different household fuels are less known. Five commonly used household fuels namely firewood, coal, dung cake, kerosene, and liquefied petroleum gas (LPG) were tested for their size-fractionated polycyclic aromatic hydrocarbon (PAHs) emission. A total of sixteen PAHs were analyzed in size fractionated combustion aerosols using HPLC-UV technique. Single box modeling approach is applied to estimate time average B[a]Peq concentration of PAHs in indoor air during cooking time. Incremental lifetime cancer risk (ILCR) of PAH exposure during cooking time was calculated, which was found to have a positively skewed distribution for all types of fuels combustion. The uncertainty and variability of the predicted exposure risk were evaluated using Monte Carlo simulation. The 50 th percentile of risk due to exposure of PAHs emissions during household use of fuels were found to be 6.25 × 10 –5 , 2.99 × 10 –5 , 9.11 × 10 –5 , 1.14 × 10 –5 , and 3.84 × 10 –6 for firewood, coal, dung cake, kerosene and LPG stove, respectively. The 50 th percentile value of risk indicates the hazard associated with solid biomass combustion is higher than non-solid fuels; the risk associated with LPG stove use is found to be one order of magnitude less compared to other fuels.

Coal fired thermal power contributes 70% of power in India. Coal fired power generation results in huge amounts of fly ash and bottom ash of varying properties. Coal, which contains the naturally occurring radionuclides, on burning results in enrichment of these radionuclides in the ashes. In the present study, coal, bottom ash and fly ash samples collected from six coal-fired power plants in India were measured for 210 Po using alpha spectrometry and for natural U, 226 Ra, 232 Th and 40 K by an HPGe γ-ray spectrometer. 210 Po in fly ash ranged from 25.7 to 70 Bq/kg with a mean value of 40.5 Bq/kg. The range and mean activities of 238 U, 226 Ra, 232 Th, 40 K in fly ash were 38.5–101 (78.1), 60–105.7 (79), 20–125 (61.7) and 43.6–200 (100) Bq/kg respectively. Fly ash and bottom ash contains two to five times more natural radionuclides than feed coal. The results were compared with the available data from earlier studies in other countries. The effect of particle size on enrichment factor of the nuclides in fly ash was studied. 210 Po showed the largest size dependence with its concentration favoring the smaller particle size while 232 Th showed least size dependence. 238 U and 226 Ra showed behavior intermediate to that of 210 Po and 232 Th. Also the correlation between sulfur content of the feed coal and activity of 210 Po was investigated. Increased sulfur content in feed coal enhanced enrichment of 210 Po in ash.

In recent years there has been growing concern all over the globe about marine pollution due to persistent organic pollutants. Sediments, which is an important component of marine environment can serve as sorbent or concentrator for these pollutants. In this study, estimation of sedimentation rate using 210 Po dating was carried out to study the depth profile of accumulated OCPs in sediments of Thane Creek Mumbai, India. The creek is a triangular mass of brackish water receiving huge municipal and industrial sewage inputs. Spatial distribution of OCPs was assessed in surface grab sediments and depth profiles of HCH and DDT were obtained in different cores. Radiological dating was performed by estimating the 210 Po activity by alpha spectrometry, whereas the OCPs determination was carried out using gas chromatography. The total HCH concentration in the surface sediment samples was in the range of 5.6–13.3 ng/g while total DDT concentration in the surface sediment samples was in the range of 3.2–5.5 ng/g. DDT and γ-HCH were the dominant OCPs in sediments from the creek. The sedimentation rate was determined using 210 Po activity measurement in different cores of the sediment and was found to be 0.67 cm/y on average. It was observed that the sediments were highly contaminated during the period of 1970–80 just after the green revolution in India. Total DDT was highest in the 1974–1978 layers of the sediments. Total HCH was highest in the 1972–1976 layers at all the locations.

Rock phosphate ore processing and disposal of phosphogypsum contribute to enhanced levels of natural radionuclides in the environment. The concentration of naturally occurring radionuclides in soil, rock phosphate and phosphogypsum samples collected around a phosphate fertilizer plant were determined. Also the external background gamma levels were surveyed.238U, 232Th, 226Ra and 40K activities in soil samples were 21–674 Bq/kg, 11–44 Bq/kg, 22–683 Bq/kg and 51–295 Bq/kg respectively. The external background gamma radiation levels in the plant premises were ranging from 48 to 133 nGy/h.

The sedimentary record of trace metals in Cochin Estuary (Southwest coast of India) during the past few decades have evaluated by analyzing core sediment and examined their ecological risk. The collected cores were examined for the depositional trends, metal enrichment, and distribution of organic carbon. Sedimentation rate was determined using the 210Po/210Pb isotope method. Chronological study reveals that Core I has aged between 1940’s to the present and Core II has been formed since 1880’s. For Core I, the average sedimentation rate obtained is 1.27 ± 0.52 cm/year, and for the Core II, it is 1.19 ± 0.23 cm/year. Both the core samples have shown similar down core distribution pattern of metals and are in the order of Zn > Cu > Pb > Cd. Metal concentration of the core samples displays an increasing trend from the bottom layer to successive upper layers. A notable variation was observed on both the core sample from 30 cm depth to the surface. The results of this study assume that the metal contamination issue of the lake system has been mounting after the industrialization of 1940's. The increase in elemental concentration after 1990's demonstrates the progressive increment and recent addition of metallic contaminants. Present study suggests regional specific preindustrial background concentration of Zn, Pb, Cu, and Cd, which can be utilized for monitoring sediment quality of the estuarine systems in India.

N-Nitrosamines (NAs) are amongst the most potent and versatile carcinogens. These compounds can be readily formed from the precursors that are widely distributed in environment. The carcinogenic NAs are capable of being formed from a wide range of nitrogen-containing substances and nitrosating agents directly in various living organisms. Nineteen edible marine species were collected from the local market of western coasts of Maharashtra, India. About 20 g of sample was homogenized with methanol, water, 1 % sulfamic acid, 1.5 M sulfuric acid (50:40:8:2) and vigorously shacked with n-Hexane. Before centrifugation, alkalization of the aqueous layer with 25 ml of 1 M KOH was done and extracted with dichloromethane. An HPLC method was optimized for the estimation of five volatile nitrosamines. These NAs were separated on a 25 cm × 4.6 mm i.d. (Lichrosphere RP-18) column (particle size 5 μm) with a high polarity mobile phase using acetonitrile water mixture (1:9). Detection of different NAs was carried out with UV detector set at 230 nm. The detection limit was found to be in the range of 0.2 to 0.4 ng for different NAs. The optimized procedure was applied for the estimation of NAs in different marine species. Effect of refrigerator storage on NAs concentration in the samples was also tested. The refrigerated storage was found to enhance the NAs concentration by many folds.

The particle size distribution of cigarette smoke is an important factor in predicting the deposition fraction of the inhaled particles in various regions of the respiratory tract. Mainstream cigarette smoke is a direct concern for smokers, while the exhaled and side stream smoke contribute to passive (second hand) smoking. The particle size distribution of tobacco smoke for mainstream and exhaled smoke has been studied in this work. This study investigates how smoking behavior, including puff volume and number of puffs, affect the particle size distribution of mainstream cigarette smoke. Scanning Mobility Particle Sizer (SMPS) was used to measure the particle size distribution of mainstream and exhaled cigarette smoke. The values of count median diameter (CMD) mobility size for the first four consecutive puffs were found to be 193 nm, 198 nm, 194 nm and 186 nm. As the volume of a puff increases from 35 mL to 85 mL, the CMD shifted slightly towards the higher particle size ranges, because of increased probability of coagulation and other combination processes. For the exhaled cigarette smoke, the growth factor was found to be 1.5 ± 0.3 with respect to mainstream cigarette smoke. The experimental results of particle size distributions were used in a Multiple Path Particle Dosimetry (MPPD) model to predict deposition patterns in the human respiratory tract. The MPPD model results show the deposition fractions for mainstream cigarette smoke were 0.163, 0.152 and 0.298 for the head, trachea and bronchi (TB) and pulmonary region, and those for exhaled cigarette smoke were 0.273, 0.064 and 0.134 respectively. The total calculated deposition fraction for mainstream and exhaled cigarette smoke was found to be 0.613 and 0.471, respectively.

We report levels of polycyclic aromatic hydrocarbons in sediment, seawater, fish and crab samples from Thane creek, India. Concentrations of sixteen USEPA PAH in sediments varies from 874 to 1925 ng g−1, dry weight (dw) in winter, between 219–495 ng g−1 in summer. In seawater Σ16 PAHs concentration during winter was recorded 706 ± 193 ng L−1, and during summer 337 ± 79 ng L−1. Total concentrations of PAHs in consumable portion of lizard fish, bombay duck and crab were found 156.8 ± 18 and 122 ± 24.5 ng g−1, 117.4 ± 17.65 ng g−1 and 95.8 ± 16.2 ng g−1, 348 ± 94.5 and 95.62 ± 31.9 ng g−1 wet weight (ww) in summer and winter respectively. PAHs concentration were compared with sediments quality guidelines viz. ERL-ERM, TEL-PEL indexes for finding ecotoxicological risk on marine organism. The ILCR values were above public screening criteria for carcinogens.

In this study, size fractionated mass and 210Po activity concentrations in mainstream cigarette smoke (MCS) were monitored for three popular cigarette brands. Size segregated collection of MCS was carried out using a cascade type impactor, while mass and 210Po activity concentration were analyzed gravimetrically and alpha spectrometry (following the radiochemical separation) respectively. Multiple-Path Particle Dosimetry (MPPD V2.11) model is used for prediction of deposition fraction calculations for the MCS deposition in different compartment of human respiratory tract. The activity concentration of 210Po is founds 10.56 ± 2.46 mBq per cigarette for the tested cigarette brands. 210Po size distribution indicates most of this associates with fine fraction (Dp