Measurements of Natural Radioactivity and Radon Levels in Water samples from Upper Egypt (original) (raw)

Radionuclides are naturally present throughout all environments, in varying amounts in air, water, plants, soil, rocks and etc. Naturally – occurring radionuclide’s are mainly derived from three separate decay chains (238U, 235U, and 232Th), and singly occurring 40K. These radionuclides may enter the human body from eating, drinking, external exposure or by inhaling. Then they penetrate into tissue and its cells, which causes ionization effects to its basic matter "cytoplasm". 222Rn is a colorless, odorless, tasteless, radioactive noble gas, which arises from the radioactive decay of 226Ra (itself a decay product of 238U). It is present in almost all rock, soil, and water, and typically moves up through the ground to the air above and into buildings through cracks and other holes in the underlying foundation. 222Rn is one of the most significant of the avoidable hazards in the environment, typically accounting for more than 50% of the dose to an average population. Measurements of natural radioactivity and radon levels in water samples from Qena governorate, Egypt, and their human impact are outlined in this thesis. This was performed by collecting two hundred twenty water samples (ground, drinking tap and mineral water) from different sites in Qena, and employing Alpha GUARD monitoring system to determine the activity concentrations of 222Rn, also gamma spectrometry "NaI(Tl)" was used to determine the activity concentrations of 222Rn, 226Ra, 232Th and 40K in ground water. In ground water samples 222Rn activity concentrations were fluctuated between 0.04±0.025 and 10.07±0.219 Bq/l, with an average value of 3.57±0.077 Bq/l. In order to check the obtained results, two radon measuring techniques (Alpha GUARD and gamma spectrometry) were applied for measure some ground water samples from all sites, and the obtained results show that the two radon measuring techniques results are in a good agreement. In the measuring ground water samples, the obtained measuring results for 226Ra, 232Th and 40K activity concentrations were fluctuated between (0.126±0.007 and 1.93±0.117), (0.037±0.003 and 0.899±0.077) and (3.18±0.273 and 7±0.602), with averages values of 0.54±0.029, 0.4±0.027 and 5.10±0.44 Bq/l, for 226Ra, 232Th and 40K, respectively. In the investigated drinking tap water samples, the obtained results for 222Rn activity concentrations show that, the activity concentrations were ranged between 0.006±0.0005 and 0.117±0.0027 Bq/l, with an average value of 0.049±0.003 Bq/l. The obtained results for 222Rn activity concentrations in the investigated mineral water samples show that, the activity concentrations were fluctuated between 0.014±0.003 and 0.237±0.005 Bq/l, with an average value of 0.077±0.002 Bq/l. The impacts of geochemical parameters of water such as PH, conductivity and TDS on the natural radionuclides activity concentration were studied, a reasonable correlation between pH and the 222Rn, 226Ra and 232Th activity concentrations were found, in which the activity concentrations decreased with increasing PH, whereas no general trend was observed that related the radionuclides activity concentrations with conductivity and TDS. Health aspects are discussed, based on calculation of the annual effective doses for different age groups, which found in values lower than the reference level.