Approaches for protection standards for ionizing radiation and combustion pollutants.

The question "can the approach used for radiation protection standards, i.e., to extrapolate dose--response relationships to low doses, be applied to combustion pollutants?" provided a basis for discussion. The linear, nonthreshold model postulated by ICRP and UNSCEAR for late effects of ionizing radiation is described and discussed. The utility and problems of applying this model to the effects of air pollutants constitute the focus of this paper. The conclusion is that, in the absence of evidence to the contrary, one should assume the same type of dose--effect relation for chemical air pollutants as for ionizing radiation.