Mechanistic considerations on the dose-rate/LET dependence of oncogenic transformation by ionizing radiations.
Brenner-DJ; Hall-EJ; Randers-Pehrson-G; Miller-RC
Radiat Res 1993 Mar; 133(3):365-369
Linear energy transfer (LET) effects in the context of cell cycle dependent models were studied. According to the biophysical model, the inverse dose rate effect disappears at very high LET because of a reduction in the number of cells being hit. It disappears at LETs below about 30 kiloelectron volts (keV)/micrometer because the majority of the dose is deposited at low values of specific energy, insufficient to produce the saturation phenomenon central to the effect. At even lower LETs, damage repair will produce the characteristic sparing associated with protraction of X-ray or gamma ray doses. The inverse dose rate effect disappears at high LET due to a reduction in the number of cells being hit. The inverse relation disappears at LETs below about 30 keV/micrometer due to the fact that most of the dose is deposited at low specific energies which are not sufficient to produce the saturation effect central to the phenomenon.
NIOSH-Publication; NIOSH-Grant; Pulmonary-system-disorders; Cytotoxic-effects; Cell-damage; Radiation-exposure; Radiation-hazards; Ionizing-radiation; Nuclear-power-plants; Cell-cultures; Dosimetry
Radiology Columbia University Health SCi 630 West 168Th St New York, NY 10032
Columbia University New York, New York, New York