Measurement of Natural Radioactivity and Radioactive Contour Maps in Soil Samples in Two Provinces in Lao PDR

Abstract

The main objective of the research is to measure the natural Radioactivity and analyze the specific activities of natural ²²⁶Ra, ²³²Th and ⁴⁰K in 137 surface soil samples from two provinces in the central part of Laos Khammuone and Savannaket Provinces. The result of the study revealed that natural ²²⁶Ra, ²³²Th and ⁴⁰K were found in soil surface with the average value of 26.5 ± 3.76 Bq/kg for ²²⁶Ra, 35.2 ± 3.2 Bq/kg for ²³²Th and 247.9 ± 16 Bq/kg for ⁴⁰K respectively. The measurement results were compared with United National Scientific Committee on the Effects of Atomic Radiation Sources and Risks of Ionizing Radiation, Report to the General Assembly with Annexes, United Nations, New York, 2000. Furthermore, radioactive contour maps of all specific activities of ²²⁶Ra, ²³²Th and ⁴⁰K were created by using ArcGIS Version 10.