Caracterización de radionucleidos presentes en fuentes termales de la provincia de Chimborazo y estimación de la tasa de dosis equivalente para la población.

Abstract

In Chimborazo province there are ten water springs with temperatures between 21-38 °C, which can be considered as thermal sources. The radiological aspects of thermal water were investigated in Chambo, Guano, Riobamba, Penipe, Colta and Alausi cantons. The specific activities of the natural radionuclides of 235 U, 212 Pb, 234 Th, 214 Pb, 214 Bi and 40 K, were determined by gamma spectrometry and by the direct evaporation method the total alpha-beta specific activity indices were estimated with a zinc sulphide scintillator doped with silver. The identified gamma-emitting radionuclides belong to the natural radioactive series of 238 U, 232 Th and 235 U. For the 238 U series, 234 Th, 214 Pb and 214 Bi were identified, with 6.1 Bq/L, 1.15 Bq/L and 1.06 Bq/L; for the 232 Th series the 212 Pb was identified with 0.72 Bq/L and in the 235 U with a value of 0.55 Bq / L; in addition, 40 K was identified with 4 Bq/L, all these values corresponding to the average concentrations of each radionuclide. The average value of the total alpha and beta activities estimated have values of 0.66 Bq/L and 0.22 Bq/L, respectively. On the other hand, when estimating the total equivalent dose rate for water immersion, it is determined that the contribution to the annual dose rate for the population is relatively low in the order of microsievert, therefore, the termal sources of Chimborazo province are considered non-radioactive.