Follow up of accidentally overexposed individuals and lessons from accidents are very important sources for establishing countermeasures against stochastic and deterministic effects caused by ionizing radiation in the field of radiation protection and safety.We have followed-up 3 victims of a 60Co radiation-device accident by analysis of the chromosome aberrations,detection of changes in gene expressions and protein levels with the whole genome gene chip and tailored protein chip,and observation of laboratory endpoints as well as clinical manifestations of the late radiation injuries.