Asaduzzaman Kh, Khandaker Mayeen Uddin, Amin Y M, Bradley D A, Mahat R H, Nor R M
Department of Physics, University of Malaya, Kuala Lumpur 50603, Malaysia.
Department of Physics, University of Malaya, Kuala Lumpur 50603, Malaysia.
J Environ Radioact. 2014 Sep;135:120-7. doi: 10.1016/j.jenvrad.2014.04.009. Epub 2014 May 8.
Soil-to-plant transfer factors (TFs) are of fundamental importance in assessing the environmental impact due to the presence of radioactivity in soil and agricultural crops. Tapioca and sweet potato, both root crops, are popular foodstuffs for a significant fraction of the Malaysian population, and result in intake of radionuclides. For the natural field conditions experienced in production of these foodstuffs, TFs and the annual effective dose were evaluated for the natural radionuclides (226)Ra, (232)Th, (40)K, and for the anthropogenic radionuclide (88)Y, the latter being a component of fallout. An experimental tapioca field was developed for study of the time dependence of plant uptake. For soil samples from all study locations other than the experimental field, it has been shown that these contain the artificial radionuclide (88)Y, although the uptake of (88)Y has only been observed in the roots of the plant Manihot esculenta (from which tapioca is derived) grown in mining soil. The estimated TFs for (226)Ra and (232)Th for tapioca and sweet potato are very much higher than that reported by the IAEA. For all study areas, the annual effective dose from ingestion of tapioca and sweet potato are estimated to be lower than the world average (290 μSv y(-1)).
土壤到植物的转移因子（TFs）对于评估土壤和农作物中放射性物质对环境的影响至关重要。木薯和红薯这两种根茎类作物，是很大一部分马来西亚人口喜爱的食物，会导致放射性核素的摄入。针对这些食物生产过程中所经历的自然田间条件，对天然放射性核素镭-226、钍-232、钾-40以及人为放射性核素钇-88（后者是沉降物的一个组成部分）的转移因子和年有效剂量进行了评估。开发了一个实验性木薯田来研究植物吸收的时间依赖性。对于除实验田之外所有研究地点的土壤样本，已表明其中含有人工放射性核素钇-88，尽管仅在生长于采矿土壤中的木薯（源自植物木薯）根部观察到了钇-88的吸收。木薯和红薯中镭-226和钍-232的估计转移因子远高于国际原子能机构报告的数值。对于所有研究区域，通过食用木薯和红薯的年有效剂量估计低于世界平均水平（290 μSv y⁻¹）。
