Radiation induced micronuclei in radiological protection and their limitations

Radiation induced cytogenetic alterations at cellular level have been studied using micronuclei (MN) in cytokinesis block (GB) binucleated human cells. Dose response relationship with graded doses of 60Co gamma rays (5-500 cGy) was established. Increased MN frequency was observed in all the cancer patients treated externally on telecobalt unit. The MN frequency increased with increasing dose of radiation. Equivalent total body dose (ETBD) in patients treated with 60Co gamma rays have been estimated based on the reference in-vitro dose response curves. The micronuclei technique has been found as a simple and rapid means of detecting DNA damage in exposed human cells and appears to have great potential to be used in assessing radiation dose in exposed individuals and in screening a population suspected to have been overexposed. (author)