國內農業用肥料對農民造成輻射劑量的調查評估

Investigation and Evaluation of the Radiation Dose 2 Caused by Domestic Agricultural Fertilizers to Farmers

劉任哲(Ren-Jer Liu) ； 柯亭含(Ting-Han Ko) ； 尤建偉(Jian-Wei You) ； 高薇喻(Wei-Yu Kao)

《臺灣農業化學與食品科學》 60卷4期 (2022/12) Pp. 156-161

https://doi.org/10.6578/TJACFS.202212_60(4).0004

摘要

本研究旨在探討國內市售肥料施用對農民造成之輻射劑量。研究使用高純度鍺輻射偵檢器測量國內製造的13件市售肥料，分析所含鐳-226、釷-232和鉀-40的放射性核種活度濃度。其中九件複合肥料樣品所含鉀-40和鐳-226的平均活度濃度分別為3339.4 ± 22.9、126.9 ± 2.8 Bq/kg；二件磷肥樣品所含鐳-226平均活度濃度為552.3 ± 3.3 Bq/kg；二件鉀肥樣品所含鉀-40和鐳-226平均活度濃度為3279.6 ± 46.4、141.7 ± 11.8 Bq/kg，均有相對較高的平均活度濃度，但所有樣品所含鐳-226、釷-232和鉀-40核種活度濃度均小於天然放射性物質管理辦法的基準值（鐳-226：1,000 Bq/kg、釷-232：1,000 Bq/kg和鉀-40：10,000 Bq/kg），再分別計算13件肥料樣品施用於農地後所造成農民之鐳當量濃度、外部危險指數、內部危險指數、吸收劑量、年有效劑量及加馬射線係數，均遠低於歐盟委員會指導方針所提出的建議值。計算所得肥料使用之年有效劑量平均值為0.606 μSv/y，遠低於一般民眾1 mSv/y之劑量限值，顯示國內正常施用肥料時不需進行輻射防護措施。

關鍵字

高純度鍺輻射偵檢器 ； 天然放射性物質 ； 吸收劑量 ； 有效劑量

並列摘要

The study aims to evaluate the radiation dose to farmers caused by domestic commercial fertilizers. A high-purity germanium radiation detector had been used to measure the radium-226, thorium-232 and potassium-40 radionuclides activity concentration of 13 domestically manufactured commercial fertilizers. Among them, the average activity concentrations of potassium-40 and radium-226 contained in nine compound fertilizer samples were 3339.4 ± 22.9 and 126.9 ± 2.8 Bq/kg, respectively. The average activity concentration of radium-226 in two phosphorus fertilizer samples was 552.3 ± 3.3 Bq/kg. The average activity concentrations of potassium-40 and radium-226 in the two potash fertilizer samples are 3279.6 ± 46.4 and 141.7 ± 11.8 Bq/kg, respectively. Activity concentration are relatively higher than other soil samples. The activity concentrations of radium-226, thorium-232 and potassium-40 in all samples were lower than the benchmark values of the Naturally Occurring Radioactive Materials Management Regulation. The results of radium equivalent concentration, external hazard index, internal hazard index, absorbed dose, annual effective dose, and gamma index are calculated to simulate the situation after 13 fertilizer samples are applied to farmland respectively, then all values are far lower than the recommended values in the European Commission guidelines. The average annual effective dose causes by using fertilizers is 0.606 microsievert (μSv/y), which is far lower than the annual dose limit of 1 mSv/y. It shows that radiation protection operations measures were unnecessary during applying fertilizers.

並列關鍵字

High-purity germanium radiation detector ； Natural radioactive material ； Absorbed dose ； Effective dose

參考文獻

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