Assessment of environmental Ra-226, Th-232 and K-40 concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia

作者：Saleh Muneer Aziz^*; Ramli Ahmad Termizi; Alajerami Yasser; Aliyu Abubakar Sadiq

来源：Journal of Environmental Radioactivity, 2013, 124: 130-140.

DOI：10.1016/j.jenvrad2013.04.013

• Environmental
• Soil
• Ra-226
• Th-232
• K-40
• Isodose

Extensive environmental survey and measurements of gamma radioactivity in the soil samples collected from Segamat District were conducted. Two gamma detectors were used for the measurements of background radiation in the area and the results were used in the computation of the mean external radiation dose rate and mean weighted dose rate, which are 276 nGy h(-1) and 1.169 mSv y(-1), respectively. A high purity germanium (HPGe) detector was used in the assessment of activity concentrations of Th-232, Ra-226 and 4 K. The results of the gamma spectrometry range from 11 +/- 1 to 1210 +/- 41 Bq kg(-1) for Th-232, 12 +/- 1 to 968 +/- 27 Bq kg(-1) for 226Ra, and 12 +/- 2 to 2450 +/- 86 Bq kg(-1) for K-40. Gross alpha and gross beta activity concentrations range from 170 +/- 50 to 4360 +/- 170 Bq kg(-1) and 70 +/- 20 to 4690 +/- 90 Bq kg(-1), respectively. These results were used in the plotting of digital maps (using ARCGIS 9.3) for isodose. The results are compared with values giving in UNSCEAR 2000.

• 出版日期2013-10