The tragic history of the exposure during the second and third decades
of this century in the United States of radium dial workers, patients
and members of the public to ionizing radiation from internally depos
ited isotopes of radium is well documented. Recognition of abnormal he
alth outcomes among female dial workers and determination of a causal
association between these outcomes among the workers and their exposur
e to radium leading to the development of protection standards is a cl
assic example of an epidemiological process whereby knowledge and unde
rstanding of ''the distribution and determinants of disease'' evolve.
Health effects studies involving U.S. female dial workers began in the
early 1920s and continued into the present decade. These studies are
discussed in the context of the epidemiological process whereby cause-
effect relationships may be postulated, evaluated and refined to the b
enefit of workers and the general public, (C) 1998 by Radiation Resear
ch Society.