No attempt has been made to express the dose that might be delivered to the body by the isotopes incorporated within the body. First, dose is defined as the energy delivered to a sensitive organ or tissue, divided by the mass of that tissue or organ.It is this author's belief that we do not know the target we should use to calculate dose for any of these radioelements. We do know that radium mimics calcium within the body, and thus most of it is found in bone.There are many other radioisotopes in the body in addition to those listed above.Most of those omitted contribute very few decays per second, and are thus trivial compared to those in the table.
Potassium is an abundant element, is an essential constituent for plant growth, is found in most soils, and is thus incorporated in growing plants. The level of potassium in the body is maintained by a homeostatic process.
Historically, such doses have been expressed as the total energy emitted by the radium and its daughters divided by the mass of bone in the body.