COMPARATIVE-STUDY OF THE DOSIMETRY OF BONE-SEEKING RADIONUCLIDES IN MAN, RHESUS-MONKEY, BEAGLE, AND MINIATURE PIG

This paper reports Monte Carlo calculations of dose factors for skeletally deposited radionuclides in man, rhesus monkey, beagle, and miniature pig. Data are presented for several comparable bones from each species for volume- and surface-seeking radionuclides, including β emitters ranging in mean particle energy from 0.025 to 0.927 MeV and the α emitters 226Ra and 239Pu. Empirical formulas are also given which relate the calculated dose factors to measured structural parameters of the individual bones. In general, the dose factors are very much higher in the beagle and miniature pig than in man, reflecting the considerable differences in bone structure between these species, and confirming the contention that extrapolation of measured radiotoxicities in animals to man must be based, at least in the first instance, on the radiation doses to the radiosensitive tissues.