a Residual is a composite of all radiogenic cancers not explicitly identified in the table.
Age-specific dosimetric models are used to convert the calculated time-dependent regional activities in the body to absorbed dose rates for both the low-LET (photons and electrons) and high-LET (alpha) radiations to radiosensitive tissues as a function of age at intake and time after the intake. Absorbed-dose rates for intake ages intermediate to the six basic ages (infancy; 1, 5, 10, and 15 y; and maturity) are determined by interpolation.
3. Lifetime cancer risk per unit intake at each age
For each cancer site, the sex-specific values of lifetime risk per unit absorbed dose received at each age (derived in the first step) are used to convert the calculated absorbed-dose rates to lifetime cancer risks for the case of an acute intake of one unit of activity at each age xi. This calculation involves integration over age of the product of the absorbed-dose rate at age x for a unit intake at age xi, the lifetime risk per unit absorbed-dose received at age x, and the value of the survival function at age x divided by the value at age xi. The survival function is used to account for the probability that a person exposed at age xi is still alive at age x to receive the absorbed dose. It is assumed that the radiation dose is sufficiently low that the survival function is not seriously affected by the number of radiogenic-cancer deaths at any age.