[en] In the case of exposure to ionizing radiation, tissue-implanted metallic materials give rise to additional backscattering doses which may be of considerable amount. Measurements have been made to derive a correlation between such additional doses, the atomic number of the scatterer material (Al, Ti, Cu, Mo, Ag, W, Pb) as well as the type and energy of radiation. The types examined were 60-Co gamma radiation, 9 MV and 15 MV bremsstrahlung and 3 MeV, 8 MeV and 12 MeV electrons. Scattering from Ag, for example, was found to give dose increments of between 22% to 35%; those from Au were extrapolated to be between 29% and 52%. (author)