The Dose Response of Chromosome Aberrations in Human Lymphocytes Induced In Vitro by Very Low-Dose gamma Rays

This paper considers the dose-effect relationship for unstable chromosome aberration yields in human lymphocytes in very low-dose range. Data are presented for (60)Co gamma-ray doses of 0, 10, 20, 40 and 1000 mGy. More than 5,000 metaphases were scored for each data point at the very low doses, and each cell was double-checked using a semi-automated metaphase finding/relocation system. Aberration yields of dicentrics plus centric rings followed an excellent linear dose response down to zero dose; the yields were significantly above the control frequency from 20 mGy