Life-shortening and disease incidence in C57Bl mice after single and fractionated gamma and high-energy neutron exposure

Journal Article · Mon Feb 01 04:00:00 EST 1988 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3577205· OSTI ID:5314043

Maisin, J R; Wambersie, A; Gerber, G B; Mattelin, G; Lambiet-Collier, M; De Coster, B; Gueulette, J

C57Bl Cnb mice were exposed to single or fractionated d(50)+Be neutrons or /sup 137/Cs gamma-ray exposure at 12 weeks of age and were followed for life-shortening and disease incidence. The data were analyzed by the Kaplan-Meier procedure using as criteria cause of death and possible cause of death. Individual groups were compared by a modified Wilcoxon test according to Hoel and Walburg, and entire sets of different doses from one radiation schedule were evaluated by the procedure of Peto and by the Cox proportional hazard model. No significant difference was found in life-shortening of C57Bl mice between a single gamma and neutron exposure. Gamma fractionation was clearly less effective in reducing survival time than a single exposure. On the contrary, fractionation of neutrons was slightly although not significantly more effective in reducing life span than a single exposure. Life-shortening appeared to be a linear function of dose in all groups studied. The data on causes of death show that malignant tumors, particularly leukemias including thymic lymphoma, and noncancerous late degenerative changes in lung were the principal cause of life-shortening after a high single gamma exposure. Exposure delivered in 8 fractions 3 h apart was more effective in causing leukemias and all carcinomas and sarcomas than one delivered in 10 fractions 24 h apart or in a single session. Following a single neutron exposure, leukemias and all carcinomas and sarcomas appeared to increase somewhat more rapidly with dose than after gamma irradiation. No significant difference in the incidence of leukemias and all carcinomas and sarcomas was noted between a single and a fractionated neutron exposure.

• Research Organization: C.E.N./S.C.K., Mol (Belgium)
• OSTI ID: 5314043
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 113:2; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACUTE EXPOSURE
ACUTE IRRADIATION
ALKALI METAL ISOTOPES
ANIMALS
BARYONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CESIUM 137
CESIUM ISOTOPES
COMPARATIVE EVALUATIONS
DISEASE INCIDENCE
DISEASES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FAST NEUTRONS
FERMIONS
FRACTIONATED IRRADIATION
GAMMA RADIATION
HADRONS
HEMIC DISEASES
IONIZING RADIATIONS
IRRADIATION
ISOTOPES
LEUKEMIA
MAMMALS
MICE
NEOPLASMS
NEUTRONS
NUCLEI
NUCLEONS
ODD-EVEN NUCLEI
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RADIOISOTOPES
RBE
RODENTS
SURVIVAL CURVES
VERTEBRATES
YEARS LIVING RADIOISOTOPES