Spectroscopic and dosimetric comparison of tooth enamel separation methods for EPR retrospective dosimetry.

Precise estimation of individual radiation dose utilizing biomaterials (fingernail, bone, and tooth) is very challenging due to their complex sample processing. Despite, tooth enamel, the most mineralized tissue of tooth is used for this purpose due to its high radiation sensitivity and ability to produce radiation induced long lived CO2- radicals. However, human teeth are not always available, and invasive nature of sample collection adds to the complexity making dose estimation difficult. In such cases, animal teeth (goat, cow, and moose) can be used as a substitute for human teeth due to comparable enamel sensitivity. Moreover, separation of enamel from dentine is a crucial step towards accurate dose estimation from irradiated teeth. In this work, Indian goat teeth were used as it was readily available to us and the comparison of goat enamel sensitivity to radiation was found to be within ∼7.4 % that of human. The enamel samples were separated following two chemical methods; (1) density separation using sodium polytungstate, (2) alkaline denaturation using NaOH and the quality was compared based on their purity and radiation sensitivity. Combined results of spectroscopic characterization using X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Raman analysis authenticated the crystallinity and purity of the separated enamel samples. The radiation sensitivity of separated enamel samples was compared by electron paramagnetic resonance (EPR) analysis as a part of dosimetric characterization. The suitability of both the samples for retrospective dosimetry and epidemiological studies was checked by validating the dose estimated from separated enamel samples with standard alanine/EPR dosimeter.

Antimicrobial activity prediction, inter- and intramolecular charge transfer investigation, reactivity analysis and molecular docking studies of adenine derivatives.

The utilization of the density functional theory (DFT) methodology has developed as a highly efficient method for investigating molecular structure and vibrational spectra, and it is increasingly being employed in various applications relating to biological systems. This study focuses on conducting investigations, both experimental and computed, to analyze the molecular structure, electronic properties and features of (E)-4-(((9H-purin-6-yl)imino)methyl)-2-methoxyphenol (ANVA). The expression ANVA should be rewritten as follows: the compound is a derivative of adenine (primary amine), specifically a vanillin (aldehyde). The present study reports the synthesis, characterization, DFT, docking and antimicrobial activity of ANVA. The optimization of the molecular structure was conducted, and the determination of its structural features was performed using DFT with the B3LYP/cc-pVDZ method. The vibrational assignments were determined in detail by analyzing the potential energy distribution. A strong correlation was observed between the spectra that were observed and the spectra that were calculated. The calculation of intramolecular charge transfer was performed using natural bond orbital analysis. In addition, several computational methods were employed, including highest occupied molecular orbital-least unoccupied molecular orbital analysis, molecular electrostatic potential calculations, non-linear optical, reduced density gradient, localization orbital locator and electron localization function analysis. This paper examines the present use of adenine derivatives in combatting bacterial and fungal infections, as well as the inclusion of spectral and quantum chemical calculations in the discussion.Communicated by Ramaswamy H. Sarma.

A novel ultrasonic non-destructive testing methodology to monitor fatigue crack growth in compact tension specimens.

Detection and evaluation of fatigue cracks in structural materials are extremely important for life prediction analysis as part of the structural integrity procedure. In this article, we present a novel ultrasonic measurement methodology, based on the diffraction of elastic waves at the crack tips, to monitor the fatigue crack growth near the threshold regime in compact tension specimens at different load ratios. The diffraction phenomenon of ultrasonic waves from the crack tip is demonstrated using a finite element 2D wave propagation simulation. The applicability of this methodology has also been contrasted with that of the conventional direct current potential drop method. In addition, the crack morphology obtained in the ultrasonic c-scan imaging showed a variation in the crack propagation plane as a function of the cyclic loading parameters. The results suggest that this novel methodology is sensitive to fatigue cracks and can form the basis of in situ ultrasonic-based crack measurements in metallic and non-metallic materials.

An experimental investigation on the combined effect of plastic deformation and grain size variation on the acoustic nonlinearity parameter.

The combined effect of grain size variation and plastic deformation on the acoustic nonlinearity parameter has been investigated in an austenitic stainless-steel material of grade 304. The nonlinear behavior of this parameter with grain growth has deviated to linear fit with deformation. This is due to the interaction of elastic waves with the strain-induced dislocation substructure in the grains. The normalized mean square strain of the deformed specimens has been estimated through angle dispersive x-ray diffraction studies using a synchrotron source, and this has been correlated with the change in the acoustic non-linearity parameter with deformation. The nonlinearity parameter is found to be very sensitive to the plastic deformation even in the presence of grain size variations. The results infer that the variations in the nonlinearity parameter can be used to have an estimate of the extent of localized deformations often occurring during the fabrication of metallic components.

Support vector machine based methodology for classification of thermal images pertaining to breast cancer.

Breast cancer has been and continues to be a cause of major health concern for women. It is more prevalent in old age, but its incidence has increased in recent years in groups below 50 years old, as in India. According to the Indian Council of Medical Research (ICMR) 2020, 50% of all the cases are in the age group of 25-50 where the numbers are staggering and constantly rising. The increase in incidence over the years indicates an urging need for innovative approaches to enhance breast cancer detection early. Thermography is non-contact imaging modalities and has potential to detect breast cancer at an early stage. Though thermography has capable of detecting breast cancer early, the challenge lies in the interpretation of the breast thermograms with respect to features and subsequent analysis. The present work discusses image acquisition, image processing related pre-processing, segmentation, and feature extraction. The extracted features were analyzed using ANOVA (Analysis of variance) statistical analysis. Statistical analyses were done in order to find the appropriate feature on the whole and quadrant breast. Statistical analysis results clearly reveal existence of thermal symmetry for the healthy subjects (p value > .05) in both whole and quadrant breast regions. In the case of abnormal subjects, whole breast analyses revealed the significance (p value < .05) for features like mean, variance, standard deviation, kurtosis, skewness, entropy, energy, homogeneity and contrast whereas upper outer quadrant analyses showed significance for all above features except contrast. The well correlated features of upper outer quadrant and whole breast were given as input for the Support Vector Machine - Radial Basis Function (SVM - RBF) classifier with grid search method. The results revealed that whole breast analysis has achieved 92.86% accuracy and upper outer quadrant breast analysis has achieved 85.71% accuracy. The results clearly indicate the involvement of upper outer quadrant and whole breast in early detection of breast cancer using thermal imaging.

Development of a numerical model for sector-average plume gamma dose and its validation with dose rate measurements at Kalpakkam NPP site, India.

A Gaussian Plume based simple numerical model, named DIFFUSE is developed to simulate the long-term sector-average plume gamma dose due to radioactive plume released during normal operation of nuclear facilities. DIFFUSE calculates site specific joint frequency distributions of wind speed, wind direction and atmospheric stability using micrometeorological observations. It performs the finite sector-average dose integration for any stack height and gamma energy using Simpson's 1/3rd method with sufficient computational efficiency within the site boundary up to 2 km. Plume dose contribution to the main plume sector from nearest and next nearest side plume sectors is also calculated. DIFFUSE is validated with a 3-month long, starting from February 2021 to April 2021, dose rate observation data during operational releases from 100 m stack of Madras Atomic Power Station, Kalpakkam, India. Meteorological data from onsite 50 m tower and continuous dose rate observation from two sets of Autonomous Gamma Dose Logger (AGDL) detectors, namely n-AGDLs and r-AGDLs, placed in two different configurations along the geometric arcs of wind sectors around the stack are used. Simulated doses are compared with look-up table based dose estimates by Hukkoo et al. (1988). Linear spatial averaging of cumulative AGDL doses on a sector arc is used as measured sector-average dose for model validation. Simulations performed for both n-AGDL and r-AGDL configurations show DIFFUSE estimated doses are ∼37% lower and Hukkoo estimated doses are at least ∼50% lower than the measured doses. Statistical analysis of DIFFUSE simulated doses shows a statistical correlation of R2∼98.3%, slope of the fit ∼1.36 for n-AGDL setup and R2∼75.3%, slope of the fit ∼1.57 for r-AGDL setup. Overall, DIFFUSE produces conservative doses compared to look-up table based doses as required by regulatory bodies.

Chromosome length ratio as a biomarker of DNA damage in cells exposed to high dose ionizing radiation.

The premature chromosome condensation (PCC) assay is considered as complementary bio-dosimetry tool for chromosome aberration assay and the PCC assay can be used to estimate high dose exposure. Though the PCC ring is considered as prospective biomarker, chromosome length ratio (ratio of longest and shortest chromosome length in PCC spreads) of chemically induced PCC is shown to be very good indicator of ionizing radiation. In view of this, an in-vitro study has been performed using PCC assay to suggest chromosome length ratio (LR) as potential bio-dosimeter induced by high dose ionizing radiation. Blood samples were collected from healthy subjects (n = 3) after prior consent and irradiated to ten different doses ranging between 0 and 20 Gy using 6 MV LINAC X-rays with dose rate of 5.6 Gy/min. Irradiated lymphocytes were cultured and calyculin induced PCC spreads were prepared. PCC spreads were captured using image analysis system and chromosome lengths were measured using open-source ImageJ software. For each dose, LR for 50 chromosome spreads were computed and mean LR value was calculated. LR varies between 6.0 ± 0.08 and 23.6 ± 0.55 for the dose range between 2 and 20 Gy. The dose response curve for LR was observed to be linear with y = 1.02x + 3.36, R2 = 0.97. Linear dose response relationship obtained in the present study confirms the prospective use of LR measurement. This study is first of its kind to examine chromosome length ratio as a biomarker of DNA damage in cells exposed to high dose X-ray exposure.

Thermal neutron sensitive inorganic compound loaded thin-film composite plastic scintillators.

The paper describes the preparation and characterization methodology of thermal neutron sensitive inorganic compound loaded polystyrene based thin-film Plastic Scintillators (PS). Inorganic compounds with thermal neutron sensitive elements such as B2O3, LiF, Gd2O2S:Tb, Gd2O3, Gd(BO2)3:Tb is loaded in plastic scintillators, at predetermined weight percentage in a solvent-based fabrication method. The PS base solution is prepared by dissolving required quantities of polystyrene, 2,5-Diphenyloxazole (PPO), 1,4-bis(5-Phenyloxazol-2-yl) Benzene (POPOP) in the p-xylene solvent. The loading material is mixed with the scintillator solution and coated over cellulose acetate-based transparency sheet. Thin sheets of 200 × 150 mm size and 250 ± 50 µm thickness PS are prepared through multiple coating. Photoluminescence (PL), Radioluminescence (RL) and pulse height spectra (PHS) of α, ß, γ and neutron sources of the composite scintillators are studied. The selection of loading compounds is decided on their physical properties such as refractive index, the atomic percentage of neutron sensitive elements in the inorganic compound, band gap, and cost and availability of material. Gadolinium based compounds as a thermal neutron absorber showed higher detection capability for low-energy neutrons. Among the gadolinium loaded PS, Gd(BO2)3:Tb (14.3 wt%) composite scintillator showed the highest RL. A comprehensive analysis of PL, RL, PHS of α, pure ß and γ sources, un-moderated and moderated Am-Be neutron source is discussed in the paper.

Comparison of Indian BOMAB and ICRP voxel phantom for calibration of shadow shield whole body counter.

In-vivo whole body monitors are calibrated with various types of phantoms like Bottle Mannikin absorption phantom (BOMAB), IGOR phantom, Masonite cut sheet phantom, realistic numerical phantoms (NORMAN, ICRP voxel phantom). These phantoms contain either point sources, rod sources, uniform source or radionuclides distributed in soft tissues etc. In this study the efficiency values of Shadow Shield wholebody counter (SSC) for 137Cs and 60Co obtained theoretically using ICRP adult voxel male reference phantom (ICRP-AM) having sources distributed in soft tissues and muscles ICRP-AM(S) are compared with the measured efficiencies of Indian BOMAB phantom having mid axial source distribution (BOM-I(A)). The results show that the efficiency value of BOM-I(A) for 137Cs and 60Co is 30% and 20% lower respectively compared to that of ICRP-AM(S). This is due to the variation in size, composition and source distribution between the two phantoms. Study using Indian Voxel phantom shows that the increase in the size of ICRP-AM contributed to an increase of 14% for 137Cs. In case of 60Co the size did not have any influence. Uniform distribution has 9% and 17% higher efficiency than axial distribution for 137Cs and 60Co respectively as shown by the simulation study using uniformly filled Indian BOMAB phantom (BOM-I(U)). The actual tissue composition and source distribution in soft tissue as shown by Indian voxel has efficiencies 12-14% higher compared to BOM-I(U). The systemic error due to the axial source distribution is recognized and quantified to be 22-25% lower compared to that of a realistic phantom with radionuclides in soft tissue and muscle. This study has resulted in an efficiency of the system using Indian realistic Voxel phantom. The efficiencies are 0.65 CPS/kBq for 137Cs and 0.49 CPS/kBq for 60Co.

MODELING AND EXPERIMENTS TO ESTIMATE RADON EMANATION FACTOR IN SOIL-GRAIN SIZE AND MOISTURE EFFECT.

The influence of soil grain size on its radon emanation mechanism was investigated by developing a Monte-Carlo model. The proposed model supplements the previous formulations by accounting for the effect elicited by specific surface area of the sample. The specific surface area of a sample is governed by its grain size and it strongly influences the emanation rate which is a surface phenomenon. The emanation study was further extended to include the moisture effect. Experiments were carried out with two soil samples; Soil-2 and Soil-4 collected from different terrains, to analyze the role played by moisture in the emanation mechanism. The above model was augmented with provisions to include the moisture input. The model could reproduce the experimental results. There is an abrupt increase in the emanation factor when the moisture content changes from 0 to 2%. Thereafter, the increase is gradual and finally becomes steady when the moisture level reaches 10%. Soil-2 and Soil-4 showed sizeable difference in their radon emanation factor values. This could be explained based on the parent226Ra distribution pattern which stems from the mineralogical composition of the samples. Quartz was predominantly found in Soil-2, whereas Soil-4 shows peaks corresponding to minerals namely ilmenite, Rutile and Zircon confirming relatively higher concentration of heavy minerals than Soil-2. The emanation factor values of the individual minerals reported in the literature were used to decide upon the 226Ra distribution depth and with this input the model to ascertain the experimental observations.

Construction of dose response curve for 6 MV LINAC X-rays using Premature Chromosome Condensation assay for radiation dosimetry.

Quantification of chromosomal aberrations in the exposed personnel blood samples is considered as a 'gold standard' and sensitive biomarker in biological dosimetry. Despite technological developments, culture of cells for 48-52 h remains an unmet need in case of triage biodosimetry. Moreover, it is difficult to get sufficient number of metaphase spreads for scoring after high doses of exposures. The technique which causes condensation of chromatin before mitosis using biological or chemical agent is named as Premature Chromosome Condensation (PCC) assay. This assay is considered as an alternative to chromosome aberration assay, particularly at high acute doses of low and high LET radiation. To establish the PCC assay, blood samples were collected from healthy non-smoking individuals (n = 3) and exposed to various doses (0-20 Gy) of 6 MV X-rays at a dose rate of 5.6 Gy/min, using a high energy Linear accelerator (LINAC). Irradiated blood samples were subjected to Calyculin-A induced PCC. About 500 cells or more than 100 Ring Chromosomes (RC) were scored at each dose. Dicentric chromosomes (DC) and acentric fragments were also scored at each dose; the number of chromosomal aberrations in G1, M, G2/M and M/A phase of cell cycle were recorded and the frequency was used to construct the dose response curve. A dose dependent increase in RC and DC frequency were observed with a slope of 0.049 ± 0.002 and 0.30 ± 0.02 respectively. This study is first of its kind to construct a dose response curve for LINAC X-rays using a PCC assay.

Biocidal (bacterial and cancer cells) activities of chitosan/CuO nanomaterial, synthesized via a green process.

Biopolymer-based nanomaterials have been developed as antimicrobial and anticancer agents due to their advanced physical, chemical and biomedical characteristics. Herein, chitosan-copper oxide nanomaterial was, successfully synthesized by a green method. In this process, copper salt was nucleated with Psidium guajava leaves extract in order to form the nanomaterial in the chitosan network. Attenuated total reflection-fourier transform, infrared spectroscopy, X-ray diffraction, Dynamic light scattering, Transmission electron microscope, Field emission scanning electron microscopy/Energy dispersive X-ray analysis, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques were, employed to characterize the synthesized nanomaterial. The average size of the nanomaterial was identified to be ∼52.49 nm with XRD. The antibacterial study of CCuO NM showed higher activity than the commercial amoxicillin against gram-positive (G + ve) (Staphylococcus aureus, Bacillus subtilis) and gram-negative (G-ve) bacteria (Klebsiella pneumonia, Escherichia coli). CCuO NM showed in-vitro anticancer potential against human cervical cancer cells (Hela) with an IC50 concentration of 34.69 µg/mL. Photoluminescence spectrum of CCuO NM showed a green emission (oxygen vacancies) observed at ∼516 nm, which is attributed to the generation of reactive oxygen species (ROS) by the nanomaterial, which is believed, to be responsible for the biocidal (cell death) effects. These results suggested that CCuO is a promising nanomaterial that could be suitable for advanced applications in the healthcare industries.

Ceramic based electronic component as retrospective radiation dosimeter.

Surface mount electronic devices (like resistors, capacitors, and inductors) extracted from the portable electronic devices (mobile phones, USB drives, etc.) have been studied for dose reconstruction using luminescence techniques for radiological or nuclear emergencies. In this work, carbon coated ceramic resistors removed from the electronic instruments are analyzed using thermo luminescence (TL) technique for the retrospective dose reconstruction. TL measurements on beta irradiated ceramic resistors exhibited one major dosimetric peak at around 540 K in addition to three other low temperature peaks. A linear beta dose response has been observed from 1 Gy to 125 Gy with Minimum Detectable Dose (MDD) of 0.1 Gy. The dose response is found to be supralinear below 1 Gy. The fading studies have been carried out and investigated up to 30 days. The important kinetic parameters for the material like TL trap depth, frequency factor and order of kinetics are evaluated by deconvolution method.

Evaluation of filtration efficacy of various types of face-masks using ambient and PAO aerosols following with different sterilization methods

Due to the ongoing pandemic, various types of facemasks such as N-95, surgical mask and cloth masks are being used as an essential protective measure. The filtration efficiency of these masks were tested before and after sterilization by different methods for two flow rates conditions corresponding to normal breathe rate (20 lpm) and during sneezing (90 lpm). Sterilization techniques used here are autoclaving (30 and 60 minutes), dry oven heating (30 and 60 minutes), gamma irradiation (15 and 25 kGy), hot water washing with and without detergent and immersing in 10% concentration of liquid hydrogen peroxide for 30 minutes. As expected, the N-95 is the greatest filtering efficiency among all the other type face masks. The best method to sterilize N-95 masks without affecting its performance is by using dry heat with temperature ranging from 70-80{degrees}C. The cloth masks and surgical mask are performed more or less same for both flow conditions. As an affordable sterilization method hot water washing is highly recommended which does not deteriorate the efficiency of the masks and can be used for the general public. The use of double or triple layer cotton cloth masks in the general public serves fit for the purpose than surgical masks. The surgical mask can be sterilized only few times with the help of dry heat, hot water wash and/or autoclave.

QUANTIFICATION OF BACK DIFFUSION IN RADON AND THORON EXHALATION RATE MEASUREMENTS.

The radon (222Rn) and thoron (220Rn) fluxes from the soil and building materials are the major contributors to their indoor levels. Hence, the measurement of radon and thoron exhalation rates from the source matrix becomes the foremost step in controlling the indoor radon and thoron exposure. It is a challenge to measure the exhalation rates without disturbing the natural conditions. The back-diffusion phenomenon modifies the exhalation rate. The work presented here is to measure the back-diffusion coefficient and takes it into consideration while estimating the exhalation rate. For radon measurements, the back-diffusion coefficient and the free exhalation rates were simultaneously estimated by adopting a novel methodology. The leak rate of the experimental setup measured by this methodology was agreeable with the value measured by adopting the standard technique. In the case of thoron, the back-diffusion effect was found to be negligible for the present experimental conditions and it is duly explained. The above results were obtained by analyzing two soil samples with high 238U and 232Th content collected from monazite-rich coastal area.

UNCERTAINTY EVALUATION IN DOSE ASSESSMENT DUE TO SPATIAL DISTRIBUTION OF NORM IN BEACH SANDS OF SOUTHEAST COAST OF INDIA: A PROBABILISTIC APPROACH.

A study on radionuclide distribution along coastal stretch in high background areas is constantly attracted to many researchers around the world. In the present study, the concentration of radionuclides in beach sands along the southeast coastal region of India has been studied in detail. Concentration of radionuclides is measured using gamma spectrometry at 148 pre-determined locations. It is found that 238U and 232Th concentrations are varying in the range from 3 (BDL) to 298.9 and 1150.2 Bq kg-1, respectively. Concentration of 40K in beach sand varied from 11 to 1743.4 Bq kg-1. The measured activity levels of radionuclides were compared with earlier studies carried out by various researchers in the same region under study. The related radiological parameters of interest were also determined and compared with the internationally recommended values. With an increase in emphasis on quality in dose assessment methods, dose to human population living in the vicinity requires uncertainty evaluation, which is carried out by taking into account variation in the activity values. This study would serve as a baseline radiological mapping for the southeast coast region of India for environmental impact assessment prior to plan of nuclear facility in the future.

Gamma ray buildup factors for conventional shielding materials and buildup factors computed for tungsten with a thickness beyond 40 mean free paths.

In this study, gamma ray buildup factors were investigated for conventional shielding materials such as lead, iron, concrete, and tungsten based on standard formulations in order to understand the variations between different formulations. The exposure buildup factors for 1 MeV gamma rays in lead, iron, and concrete for thicknesses beyond 40 mean free paths were computed using the modified geometric progression fitting formula and compared with previously reported data. For the first time, the exposure buildup factors were computed for tungsten at gamma ray energies from 15 keV to 15 MeV and for a penetration depth beyond 40 mean free paths.

Correlation between cytogenetic biomarkers obtained from DC and CBMN assays caused by low dose radon exposure in smokers.

Purpose: Radon is of health concern because they can cause lung cancer when inhaled over many years. Cytogenetic biomarkers proved to be excellent methods to detect and estimate radiation induced DNA damage. Two well established cytogenetic assays are available to detect the DNA damage caused by ionizing radiation namely Dicentric (DC) assay and Cytokinesis-Blocked Micro Nucleus (CBMN) assay. Chromosomal aberrations such as dicentric and acentric fragments can be analyzed in DC assay. Micronuclei and Nucleoplasmic bridges can be analyzed in CBMN assay. The present study focuses on correlation between the aberrations observed in DC and CBMN assay caused by low doses of radon in smokers. Material and methods: Blood samples were collected, after prior consent, from smokers as well as healthy non-smoking individuals and exposed in vitro to radon ranging between 0-5.2 mGy using a simple, portable irradiation assembly designed and tested at authors' laboratory. Results: A significant increase in frequencies of dicentrics and excess acentric fragments were observed with increasing dose. Interestingly in CBMN assay also, the frequencies of micronuclei and nucleoplasmic bridges were increased with dose. There was a significant correlation between nucleoplasmic bridges and dicentrics for both smokers and non-smokers. Significant correlation between acentric fragments and micronucleus was observed only for non-smokers. Conclusions: By considering the correlation between the two cytogenetic assays, the CBMN assay can be used as an alternative to DC assay for non-smokers. In case of smokers, nucleoplasmic bridges can be used to measure the radiation exposure. This study is first of its kind to correlate the cytogenetic biomarkers obtained from DC and CBMN assay for smokers with very low doses of radon.

A REVIEW ON 210Po AND 210Pb IN INDIAN SEAFOOD AND DOSE TO CONSUMERS.

India is the second largest seafood producer in the world marketing more than 7000 edible species. In this regard, commendable studies have been conducted since the 1970s by different research groups and more data are reported. In this work, all the studies on 210Po and 210Pb measurements in abiotic and biotic components of India have been combined and reviewed. The concentrations of 210Po and 210Pb are estimated by radiochemical separation followed by alpha counting. Grain size, season, Tsunami waves and place of sampling have a decisive bearing on 210Po and 210Pb concentration in abiotic components. Plankton shows a higher Kd factor (104) compared to seaweeds and sea grass (103). Pond ecosystems recorded the highest Kd factor (4·3 × 104) compared to other freshwater and marine ecosystems. Bioaccumulation of 210Po and 210Pb varies with respect to variety of seafood. The committed effective dose (CED) calculated for shellfish species maintained a higher range of 2.5 × 10-2 mSv/y to 9.8 × 10-1 mSv/y and for fish species fluctuated from 3.8 × 10-4 mSv/y to 2.0 × 10-1 mSv/y. The studies conducted so far are scattered, and need to be gathered for future reference and planning (i.e. There is not much information available for Kerala, Karnataka, Maharashtra, Gujarat, Andhra, West Bengal and Odessa coast). Therefore, it is strongly recommended that further and more complete research is undertaken to study the bioaccumulation of 210Po and 210Pb from seafood. Overall, the present review concludes that Indian seafood is radiologically safe.

Utilization of induction furnace steel slag in concrete as coarse aggregate for gamma radiation shielding.

The present investigation highlights the utilization of Induction Furnace (IF) steel slag as a partial replacement for coarse aggregate in concrete. The concrete blocks of size 150 × 150 × 50 mm were casted and the effect of density, compressive strength, linear attenuation coefficient, Gamma Attenuation Factor (GAF) and Half Value Layer (HVL) has been explored. Gamma attenuation measurements were carried out using NaI (Tl) based gamma detector. Gamma ray source 60Co emitting two gamma energies 1.17 and 1.33 MeV was used for radiation measurements. The results of this present study shows that 50% of IF steel slag replacement increases the density (2.81 g/cm3) and compressive strength (29.11 N/mm2). The Linear attenuation coefficient (0.1953 cm-1-0.2236 cm-1) and GAF (0.6343-0.6710) is higher at 50% replacement of IF steel slag than conventional concrete. HVL values were also having positive impact in 50% replacement of IF steel slag (3.10 cm) in concrete than conventional concrete (3.55 cm). The partial replacement of IF steel slag as coarse aggregate in concrete is effective in gamma shielding.