Inactivation cross sections for mammalian cells exposed to charged particles: a phenomenological approach.
Published data on inactivation of V79 cells irradiated with monoenergetic proton and ion beams (He, C, O, Ne) have been analysed. Values for RBE alpha, RBE10% and the inactivation cross section sigma have been evaluated in the LET range between 5 and 400 keV.micron-1. RBE against LET curves and inactivation cross sections against LET and against Z*2/beta 2 curves have been studied in a comparative approach with respect to the different ion types. RBE-LET curves depend strongly on the type of ion for LET > 30 keV.micron-1. At LET < 30 keV.micron-1 and low doses protons show the greatest effectiveness; at LET > 30 keV.micron-1 and high doses He ions provide the most effective radiation. Apart from protons, separation among the various ion curves is less marked in the sigma against Z*2/beta 2 plot than in the sigma against LET plot. sigma against Z*2/beta 2 curves for ions with 2 < or = Z < or = 10 and 200 < Z*2/beta 2 < 1500 show a common trend independent of Z and are well represented by a linear relationship.
Belloni
F
F
Dipartimento di Fisica dell'Università di Milano and INFN, Sezione di Milano Via Celoria, 16, 20133 Milano, Italy. Fabio.Belloni@mi.infn.it
Bettega
D
D
Calzolari
P
P
Cherubini
R
R
Massariello
P
P
Tallone
L
L
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects*; D002522:Chlorocebus aethiops; D004307:Dose-Response Relationship, Radiation; D018499:Linear Energy Transfer; D008322:Mammals; D011839:Radiation, Ionizing