School of Physics, University Sains Malaysia, 11800 Penang, Malaysia.
Radiat Prot Dosimetry. 2020 Jun 12;188(1):47-55. doi: 10.1093/rpd/ncz256.
Tapioca and sweet potato are the fourth and fifth most consumed crops in Malaysia. The activity concentrations of natural radionuclides in these vegetables were assessed from two regions in Malaysia (Kedah and Penang) along with soil samples using gamma ray spectroscopy. The transfer factors of 226Ra, 232Th and 40K from soil to vegetables were calculated, and a dose assessment was performed. The activity concentrations of 226Ra, 232Th and 40K in soil samples did not show a significant variation with the regions investigated, and the average values obtained, in Bq/kg, (±SD) were as follows: 80 ± 41, 56 ± 12, 516 ± 119, respectively. The respective average activity concentrations in vegetables were as follows, in Bq/kg: (±SD) 2.0 ± 0.5, 6 ± 2, 153 ± 49. The corresponding transfer factors were calculated to be 0.03, 0.11 and 0.31 for 226Ra, 232Th and 40K, respectively. The average annual effective doses due to the exposure from soil and ingestion of vegetables were found to lie within the worldwide ranges.
木薯和红薯是马来西亚第四大和第五大消费作物。本研究采用伽马能谱法，对马来西亚两个地区（吉打州和槟城）的这些蔬菜以及土壤样本中的天然放射性核素活度浓度进行了评估。计算了 226Ra、232Th 和 40K 从土壤到蔬菜的转移系数，并进行了剂量评估。土壤样本中 226Ra、232Th 和 40K 的活度浓度与研究区域没有明显变化，获得的平均值（Bq/kg，±SD）分别为：80±41、56±12、516±119。蔬菜中的相应平均活度浓度（Bq/kg）分别为：（±SD）2.0±0.5、6±2、153±49。相应的转移系数分别为 226Ra 的 0.03、232Th 的 0.11 和 40K 的 0.31。由于土壤暴露和蔬菜摄入而导致的平均年有效剂量被发现处于世界范围内。
