Induced radioactivity in tissues caused by high energy protons

Theoretical and experimental investigations were performed to study the induced activity in biological objects with the identification of nuclides, the definition of their contribution to the absorbed dose and of the levels of internal and external irradiation from activation of β- and γ-radiation with the local effect of a proton beam at 1000 MeV. Research was conducted using a medical proton beam at 100 MeV on the synchrocyclotron at the Institute of Nuclear Physics, Academy of Sciences of the USSR, Leningrad. Contribution of induced activity does not exceed 0.1 % of the absorbed dose of proton radiation. The level of external irradiation from the fission of β-active nuclides in the tissue should be taken into account by the staff who are brought into direct contact with an irradiated biological object in the first 30 min after the accelerator is switched off. Eye protection should be specially envisaged