Dose estimations of fast neutrons from a nuclear reactor by micronuclear yields in onion seedlings.
Irradiations of onion seedlings with fission neutrons from bare, Pb-moderated, and Fe-moderated 252Cf sources induced micronuclei in the root-tip cells at similar rates. The rate per cGy averaged for the three sources, <bn>, was 19 times higher than rate induced by 60Co gamma-rays. When neutron doses, Dn, were estimated from frequencies of micronuclei induced in onion seedlings after exposure to neutron-gamma mixed radiation from a 1 W nuclear reactor, using the reciprocal of <bn> as conversion factor, resulting Dn values agreed within 10% with doses measured with paired ionizing chambers. This excellent agreement was achieved by the high sensitivity of the onion system to fast neutrons relative to gamma-rays and the high contribution of fast neutrons to the total dose of mixed radiation in the reactor's field.
Fujikawa
K
K
Laboratory of Radiation Biology, Kinki University, Higashiosaka, Japan. genken@ned.kindai.ac.jp
Endo
S
S
Itoh
T
T
Yonezawa
Y
Y
Hoshi
M
M
D005214:Fast Neutrons; D015162:Micronucleus Tests / Q000379:methods*; D009688:Nuclear Reactors; D019697:Onions / Q000528:radiation effects; D011836:Radiation Tolerance; D011874:Radiometry / Q000379:methods