Asynchronous cultures of exponentially growing mouse C3H10T1/2 cells were irradiated with 250 kVp X-rays delivered in single total doses, graded from 35 to 140 cGy.
Immediately after irradiation cells were trypsinized, diluted and replated for standard assay of onclogical transformation.
It was found, that in this dose region the transformation frequency corrected for survival of C3H10T1/2 cells after exposure to 250 kVp X-rays increased linearly with increasing total dose.