title: Gamma residual radioactivity measurements on rats and mice irradiated in the thermal column of a TRIGA Mark II reactor for BNCT.
abstract: 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.
authors.affiliation: *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.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Protti
authors.forename: Sergio
authors.initials: S
authors.lastname: Manera
authors.forename: Michele
authors.initials: M
authors.lastname: Prata
authors.forename: Daniele
authors.initials: D
authors.lastname: Alloni
authors.forename: Francesca
authors.initials: F
authors.lastname: Ballarini
authors.forename: Andrea Borio
authors.initials: AB
authors.lastname: di Tigliole
authors.forename: Silva
authors.initials: S
authors.lastname: Bortolussi
authors.forename: Piero
authors.initials: P
authors.lastname: Bruschi
authors.forename: Marcella
authors.initials: M
authors.lastname: Cagnazzo
authors.forename: Maria
authors.initials: M
authors.lastname: Garioni
authors.forename: Ian
authors.initials: I
authors.lastname: Postuma
authors.forename: Luca
authors.initials: L
authors.lastname: Reversi
authors.forename: Andrea
authors.initials: A
authors.lastname: Salvini
authors.forename: Saverio
authors.initials: S
authors.lastname: Altieri
mesh_terms: D000818:Animals; D016754:Boron Neutron Capture Therapy; D005720:Gamma Rays; D008175:Lung Neoplasms / Q000532:radiotherapy; D051379:Mice; D009010:Monte Carlo Method; D009502:Neutrons; D009688:Nuclear Reactors; D011835:Radiation Protection; D011880:Radiotherapy Planning, Computer-Assisted; D051381:Rats; D012062:Relative Biological Effectiveness