Calculated Energy Deposits from the Decay of Tritium and Other Radioisotopes Incorporated into Bacteria

Transmutation of the radioisotope tritium occurs with the production of a low energy electron, having a range in biological material similar to the dimensions of a bacterium. A computer program was written to determine the radiation dose distributions which may be expected within a bacterium as a result of tritium decay, when the isotope has been incorporated into specific regions of the bacterium. A nonspherical model bacterium was used, represented by a cylinder with hemispherical ends. The energy distributions resulting from a wide variety of simulated labeled regions were determined; the results suggested that the nuclear region of a bacterium receives on the average significantly different per decay doses, if the labeled regions were those conceivably produced by the incorporation of thymidine-³H, uracil-³H, or ³H-amino acids. Energy distributions in the model bacterium were also calculated for the decay of incorporated ¹⁴carbon, ³⁵sulfur, and ³²phosphorous.