Effect of radioactive materials on environmental health.

In a recent discussion relating to environmental health, Mark D. Hollis (1) indicated that public health officials will be responslible for protecting the population against the harmful effects of ionizing radiation. Ionizing radiations result from the disintegration of unstable nuclei and are damaging to living tissue. The radiation may originate from an external source or from radioactive materials within the body. Radiation from an external source may affect the body as a whole, if there is no shielding, or may be made to affect only certain portions of the body, as in radium treatment of a tumor. Effects of damage from radioactive materials within the body depend on several factors: the quantity of radioactive material present in the body; the type of radiation, whether alpha, beta, or gamma; and the half-life or rate of decay of the material. Other factors to be considered are the organ or organs of localization; rate of excretion from the body, i. e., the biological half-life; the physical state of the individual; etc. All of these factors are considered in determining the maximum permissible concentration (MPC) for each radioisotope