The conventional approach for radiation protection is based on the ICRP's linear,
no threshold (LNT) model of radiation carcinogenesis, which implies that ionizing
radiation is always harmful, no matter how small the dose. But a different approach
can be derived from the observed health effects of the serendipitous contamination
of 1700 apartments in Taiwan with cobalt-60 (T(1/2) = 5.3 y). This experience indicates
that chronic exposure of the whole body to low-dose-rate radiation, even accumulated
to a high annual dose, may be beneficial to human health. Approximately 10,000 people
occupied these buildings and received an average radiation dose of 0.4 Sv, unknowingly,
during a 9-20 year period. They did not suffer a higher incidence of cancer mortality,
as the LNT theory would predict. On the contrary, the incidence of cancer deaths in
this population was greatly reduced-to about 3 per cent of the incidence of spontaneous
cancer death in the general Taiwan public. In addition, the incidence of congenital
malformations was also reduced--to about 7 per cent of the incidence in the general
public. These observations appear to be compatible with the radiation hormesis model.
Information about this Taiwan experience should be communicated to the public worldwide
to help allay its fear of radiation and create a positive impression about important
radiation applications. Expenditures of many billions of dollars in nuclear reactor
operation could be saved and expansion of nuclear electricity generation could be
facilitated. In addition, this knowledge would encourage further investigation and
implementation of very important applications of total-body, low-dose irradiation
to treat and cure many illnesses, including cancer. The findings of this study are
such a departure from expectations, based on ICRP criteria, that we believe that they
ought to be carefully reviewed by other, independent organizations and that population
data not available to the authors be provided, so that a fully qualified epidemiologically-valid
analysis can be made. Many of the confounding factors that limit other studies used
to date, such as the A-bomb survivors, the Mayak workers and the Chernobyl evacuees,
are not present in this population exposure. It should be one of the most important
events on which to base radiation protection standards.