Microdosimetry of alpha-emitting decay products in tissue using conventional film autoradiography

Presented work describes a practical method using conventional photographic films; specifically, Ilford Pan F Plus 135-36, Black & White, ISO 50 film for obtaining images of alpha tracks. A variety of alpha radiation sources including electrodeposited planchets, Bomarc soil, and samples of bone containing Ra-226 were placed directly on the film for up to 3 days. Post-exposure the film was developed using standard darkroom techniques with Kodak D-76 developer for 7 min, stop bath, and fixer. Tracks consisting of five or more grains were counted using an Olympus BX51 microscope at x10 magnification in a 9 cm(2) circular field-of-view. Initial analysis shows an efficiency of approximately 34.9 % with an uncertainty in track counts of +/- 2.4 % for the monoenergetic particles.