THE RELATIVE BIOLOGICAL EFFICIENCY OF SINGLE DOSES OF FAST NEUTRONS AND GAMMA-RAYS ON VICIA FABA ROOTS AND THE EFFECT OF OXYGEN. II. CHROMOSOME DAMAGE: THE PRODUCTION OF MICRONUCLEI

Journal Article · Wed Jul 01 04:00:00 EDT 1959 · Intern. J. Radiation Biol.

DOI:https://doi.org/10.1080/09553005914550311· OSTI ID:4237563

Evans, H J; Neary, G J; Williamson, F S

The frequency of micronuclei resulting from acentric chromosome and chromatid fragments induced by cobalt60 gamma radiation and by approximately 3 Mev fast neutrons has been studied in the root-tip meristematic cells of Vicia faba. Roots irradiated with gamma-ray doses of 107 and 188 rads whilst in aerated water showed a greater micronuclear frequency than roots irradiated with similar doses in the absence of oxygen. The ratio of doses given in nitrogen and in air in order to produce the same micronuclear yield was found to be about 2.4. With roots irradiated with fastneutron doses of 2.02, 4.95, and 9.94 rads the effect of oxygen is less marked, the nitrogen/air dose-ratio being about 1.4. For a given level of chromosome damage produced under conditions of aeration, neutron radiation was found to be about 10.5 times as effective as gamma-rays. Because of the quantitative difference in the response of the two types of radiation to the presence of oxygen, the relative biological efficiency of neutrons to gamma-rays under anoxic conditions would be about 18 to 1. (auth)

• Research Organization: Medical Research Council Radiobiological Research Unit, Harwell, Berks, Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-14-002322
• OSTI ID: 4237563
• Journal Information: Intern. J. Radiation Biol., Journal Name: Intern. J. Radiation Biol. Vol. Vol: 1
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AIR
BIOLOGY AND MEDICINE
CHROMOSOMES
COBALT 60
CYTOLOGY
FAST NEUTRONS
GAMMA RADIATION
NITROGEN
OXYGEN
PLANTS
RADIATION DOSES
RADIATION INJURIES
RBE
ROOTS
VICIA
VICIA FABA
WATER