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Gamma Radiation Profile of the High Background Radiation Area along Southwest Coastal India and its Neighbourhood
2023
Sukumaran Chettiar Rajamma, Soniya | Abraham, Sunila | Panakal John, Jojo
Radioactive contamination of the earth’s biosphere has always been a source of concern. From the health point of view, radiation exposure and dose delivered to human beings are of prime importance. Certain parts of coastal southwest districts of the state of Kerala in India namely Thiruvananthapuram (Trivandrum), Kollam (Quilon) and Alappuzha (Alleppey) are known high background radiation areas (HBRA) owing to the presence of rich quantities of thorium and uranium. Surface soil samples from these districts' HBRAs and adjoining regions were studied for their primordial radionuclide levels using NaI(Tl) based gamma-ray spectrometry. Specific activities of 226Ra, 232Th and 40K nuclides in soil samples from the whole study area were between 4.7 Bq/kg to 130 Bq/kg, 6.5 Bq/kg to 611 Bq/kg and 101 Bq/kg to 1852 Bq/kg, respectively. Important dosimetric parameters namely radium equivalent activity (Raeq), absorbed gamma dose (D), Indoor and outdoor Annual Effective Dose equivalents (AEDin & AEDout), internal and external hazard indices (Hin & Hex) for gamma exposure, and Excess Lifetime Cancer Risk (ELCR) were also determined to assess probable health effects on human beings residing in these regions. A comparison of average specific radioactivities and average indoor annual effective doses between the HBRA and Normal background Radiation Area (NBRA) is presented. Results show that the neighbouring regions have considerably lower radiation dosimetric parameters.
Show more [+] Less [-]Evaluation of natural radioactivity of soil samples from different regions of Wassit governorate
2017
Najam, Laith | Karim, Mahmood | Hameed, Taghreed
The present paper measures natural radioactivity in different areas of Wassit governorate, using (HPGe) detector. Gamma spectrum analysis for each sample along with caululated specific activity show that the average concentrations of U-238, Th-232, and K-40 have been 19.420±4.7 Bq/kg, 18.487±5.05 Bq/kg, and 204.266±46.9 Bq/kg respectively, which is lower than the worldwide average value. While the average value of Radium equivalent, absorbed dose, indoor and outdoor annual effective dose, activity index, and internal and external hazard index for each sample have been found to be 85.182 Bq/kg, 39.962 nGy/h, 0.196 mSv/y, 0.049 mSv/y, 0.374, 0.313, 0.309, and 0.230 respectively, all of them are lower than the permissibility limit value.
Show more [+] Less [-]Comparing the Effect of Kerosene Pollution on Forest and Industrial Soil Microbial Community
2016
Ziadabadi, Zahra | Hassanshahian, Mehdi
Kerosene is the colorless liquid and slightly heavier than gasoline thatspecific odor removes after evaporation. Soil and underground water source arecontaminated with different pollutants such as petroleum hydrocarbons. These pollutantshave various negative environmental effects on soil and surrounding environment. Theaim of this research is to understand the effect of kerosene pollution on two differentsoils. The two different collected soils include Industrial and Forest soil. Six microcosmswere designed. Indeed, each soil has three microcosms: unpolluted microcosm, pollutedmicrocosm, and polluted microcosm with nutrient (Nitrogen and Phosphor). Some factorswere assayed in each microcosm during 120 day of experiment. These factors includetotal heterotrophic bacteria, total kerosene degrading bacteria, dehydrogenase enzyme,and kerosene biodegradation. The results of this study show that the highest quantity ofheterotrophic bacteria is related to forest soil (6×109). The quantities of kerosenedegrading bacteria significantly were lower than heterotrophic bacteria in all soilmicrocosms. The quantity of kerosene degrading bacteria have decrement pattern until60th day of experiment, but, after this day, these bacteria have increment pattern. The bestdehydrogenase activity between different microcosms is related to polluted microcosmwith kerosene except for farmland soil. The highest biodegradation of kerosene in allstudied soil belongs to industrial microcosm (95%). Statistical analysis of the resultsshows that there is a significant correlation between MPN quantity of heterotrophicbacteria and other assayed factrs. Also, forest soil has significant difference with othersoils. It may be possible to propose appropriate strategies for bioremediation of differentstudied soil types using the results obtained in this research.
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