Protti Nicoletta, Manera Sergio, Prata Michele, Alloni Daniele, Ballarini Francesca, di Tigliole Andrea Borio, Bortolussi Silva, Bruschi Piero, Cagnazzo Marcella, Garioni Maria, Postuma Ian, Reversi Luca, Salvini Andrea, Altieri Saverio
*Department of Physics, University of Pavia, via Bassi 6, 27100 Pavia, Italy; †National Institute of Nuclear Physics (INFN), section of Pavia, via Bassi 6, 27100 Pavia, Italy; ‡Applied Nuclear Energy Laboratory (LENA), University of Pavia, via G. Aselli 41, 27100 Pavia, Italy; §Currently at the International Atomic Energy Agency (IAEA), Wagramer Straße 5, Vienna 1220, Austria.
Health Phys. 2014 Dec;107(6):534-41. doi: 10.1097/HP.0000000000000148.
The current Boron Neutron Capture Therapy (BNCT) experiments performed at the University of Pavia, Italy, are focusing on the in vivo irradiations of small animals (rats and mice) in order to evaluate the effectiveness of BNCT in the treatment of diffused lung tumors. After the irradiation, the animals are manipulated, which requires an evaluation of the residual radioactivity induced by neutron activation and the relative radiological risk assessment to guarantee the radiation protection of the workers. The induced activity in the irradiated animals was measured by high-resolution open geometry gamma spectroscopy and compared with values obtained by Monte Carlo simulation. After an irradiation time of 15 min in a position where the in-air thermal flux is about 1.2 × 10(10) cm(-2) s(-1), the specific activity induced in the body of the animal is mainly due to 24Na, 38Cl, 42K, 56Mn, 27Mg and 49Ca; it is approximately 540 Bq g(-1) in the rat and around 2,050 Bq g(-1) in the mouse. During the irradiation, the animal body (except the lung region) is housed in a 95% enriched 6Li shield; the primary radioisotopes produced inside the shield by the neutron irradiation are 3H by the 6Li capture reaction and 18F by the reaction sequence 6Li(n,α)3H → 16O(t,n)18F. The specific activities of these products are 3.3 kBq g(-1) and 880 Bq g(-1), respectively.
目前在意大利帕维亚大学进行的硼中子俘获疗法（BNCT）实验聚焦于对小动物（大鼠和小鼠）进行体内辐照，以评估BNCT治疗弥漫性肺癌的有效性。辐照后，需要对动物进行处理，这就要求评估中子活化诱导的残余放射性以及相关的放射风险评估，以确保工作人员的辐射防护。通过高分辨率开放几何伽马能谱法测量辐照动物体内的诱导活性，并与蒙特卡罗模拟获得的值进行比较。在空气中热通量约为1.2×10(10) cm(-2) s(-1)的位置进行15分钟的辐照后，动物体内诱导的比活度主要归因于24Na、38Cl、42K、56Mn、27Mg和49Ca；大鼠体内约为540 Bq g(-1)，小鼠体内约为2050 Bq g(-1)。在辐照期间，动物身体（肺部区域除外）置于95%富集的6Li屏蔽中；屏蔽内由中子辐照产生的主要放射性同位素是6Li俘获反应产生的3H和反应序列6Li(n,α)3H → 16O(t,n)18F产生的18F。这些产物的比活度分别为3.3 kBq g(-1)和880 Bq g(-1)。
