ACUTE MORTALITY OF MICE AND RATS EXPOSED TO MIXED GAMMA-NEUTRON RADIATIONS OR TO X RAYS.

摘要

Mortality data for C57BL mice and Sprague-Dawley rats were collected as a part of the program to biologically characterize AFRRI-TRIGA reactor radiations and to provide reference information for future studies. Unilateral whole body exposures to mixed gamma-neutron radiations from the reactor or to 250 kVp x rays were carried out over a range of midline tissue doses from 370to 875rads. The 30-day median lethal doses were calcualted to be 589and 432rads for mice exposed to the x rays and to the reactor radiations,respectively. The corresponding values for the rat exposures were 740and 434rads. Using the LD50/30values as the end points for comparison,the reactor radiations were 1.4and 1.7times more effective in mice and rats,respectively,than were the x rays. The survival times of the mice and rats exposed to reactor radiations were significantly less than those of the animals exposed to similar doses of x rays. (Author)