This study presents the results of indoor and outdoor ambient gamma dose rates and radon concentration in groundwater at different locations of Koppa and Narasimharajapura taluks of Chikmagalur district, (13°40' north latitude and 75° 62' east longitudes). The total annual effective dose ranged between 0.67 mSv/y and 1.76 mSv/y with an average value of 1.16 mSv/y. The calculated total annual effective dose was found to be higher than the world average. The radon concentration in groundwater was analyzed using radon emanometry technique. The measured radon concentrations ranged from 3.96 Bq/l to 90.63 Bq/l with an average value of 35.34 Bq/l. This study reveals that 80% of drinking water samples have radon levels higher than the maximum contaminant level of 11 Bq/l recommended by the United States Environmental Protection Agency. All the recorded radon concentration values were found to be well below the action level of 100 Bq/l recommended by the World Health Organization. It is also found that the dose due to borewell water samples is higher compared to dose due to water from other sources such as hand pump, open well, and tap water.

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Soil samples were collected from Hassan district of South India. The analysis was carried out using NaI (Tl) gamma ray spectrometer. The ²³²Th activity was found to vary from 20.4 ± 1.3 Bq/kg to 136.3 ± 3.3 Bq/kg with a mean value of 56.9 ± 2.0 Bq/kg, and ²²⁶Ra activity was found to vary from 22.5 ± 1.4 Bq/kg to 90.6 ± 3.4 Bq/kg with a mean value of 41.4 ± 2.1 Bq/kg. The activity of ⁴⁰K was ranged from 278.2 ± 4.0 Bq/kg to 650.7 ± 6.7 Bq/kg with a mean value of 388.4 ± 5.1 Bq/kg. Relatively higher levels of thorium were observed in soil. The radium equivalent activity and other radiological parameters were also determined.

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Tritium (³H) is one of the important long-lived radioisotopes in the gaseous effluent from nuclear power plants. In this article, we present the results of ³H monitoring in ambient air samples around the Kaiga Nuclear Power Plant, on the West Coast of India. Air samples were collected by moisture condensation method and the ³H concentration was determined by liquid scintillation spectrometry. The ³H concentration in the 2.3–15 km zone of the power plant varied in the range of <0.04–6.64 Bq m⁻³ with a median of 0.67 Bq m⁻³. The samples collected from the 2.3–5 km zone of the power plant exhibit marginally higher concentration when compared to the 5–10 km and 10–15 km zones, which is as expected. The values observed in the present study for Kaiga region are similar to those reported from other nuclear power plants, both within India and other parts of the world.

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In the present study, Radon (²²²Rn) and Thoron (²²⁰Rn) concentration have been measured in the Bangalore University Campus using RAD7 during the postmonsoon season. The results reveal that ²²²Rn concentration ranged from 360 ± 146 to 643 ± 196 Bq/m³ with the geometric mean (GM) of 497 ± 173 Bq/m³ whereas ²²⁰Rn Concentration varied from 2668 ± 208 to 6128 ± 246 Bq/m³ with the GM of 4287 ± 262 Bq/m³. The radon and thoron exhalation rates were also calculated and found to lie between 15.62 ± 6.34 and 27.91 ± 8.51 mBq/m²/s with the GM of 21.58 ± 7.50 mBq/m²/s and 1316 ± 102 and 3024 ± 121 mBq/m²/s with the GM of 2115 ± 129 mBq/m²/s, respectively. An attempt was made to see the dependence of radon/thoron exhalation rate on few soil and atmospheric parameters. The concentration of radon and thoron was observed to be normally distributed and hence arithmetic mean, GM and median were found to be nearly same.

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Measurement of outdoor Radon-222 (²²²Rn) activity at National Atmospheric Research Laboratory (NARL), Gadanki, India, is carried out using Alpha GUARD PQ 2000 PRO from October 2011 to July 2014 and analyzed. The general inspection of time series reveals the decomposition of periodicity, significant diurnal and seasonal trend, and correlation between the measured and dependent variables. Detailed analyses have revealed that the Fast Fourier transform power spectrum of ²²²Rn has several energy peaks at different time scales that indicate the daily evolution of radon concentration. The composite seasonal plot shows that at least 21% of the average monthly radon concentration can be attributable to nonlocal effects. In a case study, it is observed that the time evolution of precipitation is one of the important governing factors of radon concentration near the surface. The activity of radon varies from 2 to 65 Bq/m³ with a mean of 12.35 Bq/m³ and ambient gamma dose levels varied between 141.8 and 244 nSv/h with a mean of 188.8 nSv/h.

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Rat C-peptide is a polypeptide molecule made up of 31 amino acids and secreted from pancreas into circulation in two isoforms I and II. Quantification of rat C-peptide II in rat serum is important as it is directly related to the diagnosis of carbohydrate metabolism abnormalities, pancreatic performance analysis, monitoring of hypoglycemia, and diabetes-related illness in rat model. The aim of the present work is to develop a tracer by chloramine-T method for radioimmunoassay (RIA) procedure and to determine the optimum amount of chloramine-T required for the preparation of stable radioiodinated product with a specific activity of around 24.97 MBq/μg, corresponding to 1 ¹²⁵I atom per molecule of the peptide. Tyrosylated rat C-peptide II was selected for the radioiodination procedure as rat C-peptide II does not contain either tyrosine or histidine which is mandatory for the incorporation of ¹²⁵I atom to the rat C-peptide II. Tyrosylated rat C-peptide II was subjected to radioiodination by chloramine-T method with different concentrations of chloramine-T and sodium metabisulfite (MBS) to obtain a stable radiolabeled compound. Optimized reaction conditions relating to the concentration of chloramine-T (10 μg) and MBS (20 μg) yielded a stable ¹²⁵I-rat C-peptide II with specific activity of 21.01 MBq/μg corresponding to 0.84 ¹²⁵I atoms per molecule of the peptide. Preparation of high integrity tracer of rat C-peptide II was achieved by combining one molecule of oxidant (chloramine-T) and two molecule of reductant (MBS).

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Natural radioactivity measurement, dose assessment, and interpretation of radiological-related parameters and radiation monitoring of the region are crucial aspects from the public awareness and environmental safety point of view. The present paper discusses the results of activity concentration of the natural radionuclides ²³⁸U, ²³²Th, and ⁴⁰K in the soil samples collected from Raichur district. ASTM procedure was followed for the sample collection and preparation for gamma spectrometric measurements. Gamma spectrometry-based 4” × 4” NaI (Tl) scintillation detector was employed for estimating activity concentrations of the gamma-emitting radioelements. Each sample was measured for a counting period of 60,000 s. The activity concentrations of the radionuclides ²³⁸U, ²³²Th, and ⁴⁰K were found in the range 10–119, 8–285, and 46–1646 Bq/kg, respectively. The activity concentrations of the radionuclides and the dose-related parameters for the samples were found to be comparable with the global literature values, except few samples. The data generated from this study are the baseline radiological data of the region for future references.

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Benchmarking the fallout ¹³⁷Cs in the coastal marine environment assumes significance in view of expansion of nuclear power plants (NPPs) in India and the Asia-Pacific region. This paper presents a snapshot of ¹³⁷Cs activity in marine coastal water samples collected around Kudankulam NPPsite across a 50 km stretch from Kanyakumari to Uvari and attempts to compare with the ¹³⁷Cs concentration observed across Indian coastal region and Asia-Pacific regional seawater. ¹³⁷Cs activity of the Kudankulam coast ranges from ≤0.40 to 1.92 mBq/L with a geometric mean (GM) value of 1.0 mBq/L. In general, ¹³⁷Cs activity in seawater of the entire Indian coastal region varies from 0.30 to 1.25 mBq/L, which may be considered as global fallout.

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The present investigation aims to study the incorporation of uranium from the bedrock to groundwater through leaching. In view of this, rock powder samples were collected in the form of slurry from the bedrock of freshly drilled borewells of the study area. The rock powder and the supernatant were separated. The gamma activity concentrations of primordial radionuclides-²³⁸U (²²⁶Ra), ²³²Th, and ⁴⁰K in the rock powder samples were measured using HP-Ge gamma-ray spectrometer. The supernatant was analyzed for the concentration of U_natusing laser-induced fluorimeter. A strong positive correlation was observed between the concentration of uranium in the rock powder and the corresponding concentration in the water samples indicating the possible leaching of uranium from the bedrock to groundwater under favorable conditions.

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The most useful technique in uranium exploration program is undoubtedly radiometric surveys. This is due to the fact that uranium emits gamma rays ranging from as low as 47kev to 2.2Mev, which can be detected and quantified using suitable radiation detector. Combination of aerial radiometric surveys, ground examination of the detected anomalies, followed by drilling and gamma ray logging of drilled boreholes has resulted in the identification of large uranium resources. Borehole logging provides the most important subsurface information required for the uranium exploration program. An area known to contain only uranium, computed gamma ray logging with a Geiger Muller (GM) Detector rapidly gives the required subsurface radioactivity information whereas, in a heterogeneously mineralized area of uranium with thorium, logging data using GM detector may mislead to wrong interpretation. Under such condition, using the principle of gamma ray spectrometry, scintillation detector-based spectral gamma ray logging is carried out. Identifying uranium in the presence of thorium is a complex process and this paper deals with a case study on the spectral gamma ray logging carried out to locate the subsurface uraniferous zone in Pakkanadu area, Salem district of Tamil nadu, where the surface anomaly indicated the presence of high thorium content. The various limitations such as small detector size, large sample volume, high-correction factor required for quantifying the individual elements, and the study carried out for optimizing the time required for data acquisition are discussed.

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Uranium mineral in a geological environment may behave like an open system. Various factors such as mobility of radium, α-recoil of ²³⁴U causing migration of uranium radioisotopes, and radon emanation lead to disequilibrium in uranium decay series. A study has been carried out to find the disequilibrium status of subsurface samples of Rasimalai area of Vellore district and Pakkanadu area of Salem district, Tamil Nadu. This study has a significance in connection with exploration of atomic minerals. It was observed that samples of Rasimalai area show a disequilibrium in favor of parent uranium whereas samples from nearby Pakkanadu area are in equilibrium.

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