Natural Radionuclides in Medicinal Plants and Forages from a Granite Mountain area, Phangan Island, Surathani Province.

Abstract

The radioactive nuclides were a cancer causing agent. They have a source of origin from nature and man-made. The natural radioactive elements were found in granite rock. The purpose of this research were analyze the activity of radioactive nuclides (226Ra, 232Th and 40K) in herbs and forage plant samples from Koh Phangan District, Surat Thani Province and to analyze the Annual external effective dose rate (E). A total of 20 species of plants, including medicinal plants and food chains plant were randomly sampled. The plant samples were analyzed by the gamma spectrometry system with high-purity germanium (HPGe) detector. It was found that the radioactive nuclides of 226Ra, 232Th and 40K were ranged from 6.75 ± 0.16 to 61.55 ± 0.48, 1.76 ± 0.15 to 34.24 ± 0.25 and 330.74 ± 0.37 to 1337.54 ± 0.64 Bq/kg, respectively. In addition, the Annual external effective dose rate (E) in all plants were lower than required (UNSCEAR, 2000).