2056-2057 / 2063
Summary: Radiation 1
•
Radiation carcinogenesis is a
stochastic effect
•
Human experience includes early workers
exposed occupationally,
patients exposed to
medical irradiation
, survivors of
A-bomb attacks
on Hiroshima and Nagasaki, and
Chernobyl
•
Shortest
latency
is for leukemia, which peaks at 5 to 7 years.
For solid tumours, latency may extend to > 60 years
•
Radiation-induced cancer risks are usually based on a time-related
Relative Risk
(RR) model
•
A dose and dose-rate effectiveness factor (DDREF) converts risk
estimates from acute exposures (
e.g.
A-bomb data) to the low dose
and low dose rates encountered in radiation protection.
ICRP conservatively assumes
DDREF = 2