The invention provides for a method for producing isotopes using a beam of particles from an accelerator, whereby the beam is maintained at between about 70 to 2000 MeV; and contacting a thorium-containing target with the particles. The medically important isotope 225Ac is produced via the nuclear reaction (p,2p6n), whereby an energetic proton causes the ejection of 2 protons and 6 neutrons from a 232Th target nucleus. Another medically important isotope 213Bi is then available as a decay product. The production of highly purified 211At is also provided.