Estudio de trazas nucleares de radionúclidos alfa presentes en el ambiente usando detectores de policarbonato CR-39

Abstract

The current degree project presents an analysis of the nuclear traces left by alpha particles from radionuclides present in the environment (indoor) and coming from food samples (carrot and coffee) and three types of rocks (Italian volcanic tuff widely used for construction in Italy and two stones with high uranium-238 content), using CR-39 polycarbonate detectors and a Motic optical microscope of the BA210 series. Standard chambers were used for indoor monitoring and non-standard diffusion chambers were designed where the detectors were placed for exposure to the samples. The indoor radon concentration monitored in four locations in the city of Riobamba and one in the canton of Colta showed a maximum value of 18,87 ± 2,82 Bq/m3 in the bunker of the Nuclear Techniques Laboratory of the ESPOCH and a minimum value of 9,04 ± 1,83 Bq/m3 in the Abya Yala Educational Unit in the parish of Columbe. The food and material samples showed significant variability in terms of mass exhalation rate. The maximum value (68,32 ± 10,29 Bq /kg h) corresponds to uranium stone 1, with a mass of 0,00071 kg. The minimum value (0,013 ± 0,002 Bq /kg h) corresponds to the carrot sample with a mass of 0,035 kg. The results of the surface exhalation rate of radon gas, calculated for the crushed samples of carrot, coffee and Italian volcanic tuff, show that the volcanic tuff has a very high value (4,268 ± 0,679 Bq / m2 h) compared to carrot (0,121 ± 0,024 Bq / m2 h) and coffee (0,197 ± 0,035 Bq / m2 h). It is recommended to control the