Neutron irradiation of bacteria in the presence and absence of secondary charged-particle equilibrium

Journal Article · Mon Sep 01 00:00:00 EDT 1980 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3575341· OSTI ID:6817830

Lunec, J; Cramp, W A; Hornsey, S

The survival rate of Shigella flexneri has been measured for irradiation with 7-MeV neutrons in the presence and absence of secondary charged-particle equilibrium. The data were analyzed to assess the separate response of the cells to the knock-on proton and ..cap alpha..-particle plus heavy-recoil components. A detailed consideration of the frequency of ..cap alpha..-particle and heavy-recoil traversals of the cell has been made to explain our results, and in addition we have applied this approach to analyze the earlier results obtained with mammalian cells. We conclude that of the secondary charged-particles produced by the Hammersmith neutron beam, the highest LET particles, the heavy-recoil nuclei, contribute a minor proportion of damage to bacteria but form a major contribution of damage in mammalian cells. The reduction in oxygen enhancement ratio (OER) with neutrons compared with low LET radiation for mammalian cells is due almost entirely to the influence of the heavy recoils and the contribution of the ..cap alpha..-particle and knock-on protons to the reduction of the OER is relatively minor. For Shigella flexneri the ..cap alpha.. particles and heavy recoils make approximately equal contributions to the reduction in OER.

• Research Organization: Hammersmith Hospital, London, England
• OSTI ID: 6817830
• Journal Information: Radiat. Res.; (United States), Vol. 83:3
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
SHIGELLA
BIOLOGICAL RADIATION EFFECTS
ALPHA PARTICLES
ANIMAL CELLS
ELECTRONS
EXPERIMENTAL DATA
LET
MAMMALS
MEV RANGE 01-10
NEUTRON BEAMS
OXYGEN ENHANCEMENT RATIO
PROTONS
RECOILS
SURVIVAL CURVES
ANIMALS
BACTERIA
BARYONS
BEAMS
BIOLOGICAL EFFECTS
CHARGED PARTICLES
DATA
ELEMENTARY PARTICLES
ENERGY RANGE
ENERGY TRANSFER
FERMIONS
HADRONS
INFORMATION
LEPTONS
MEV RANGE
MICROORGANISMS
NUCLEON BEAMS
NUCLEONS
NUMERICAL DATA
PARTICLE BEAMS
RADIATION EFFECTS
VERTEBRATES
560131* - Radiation Effects on Microorganisms- Basic Studies- (-1987)
550700 - Microbiology