Chronic radiation syndrome ( CRS ) is a constellation of health effects of radiation that occur after months or years of chronic exposure to high amounts of radiation . Chronic radiation syndrome develops with a speed and severity proportional to the radiation dose received , i.e. , it is a deterministic effect of exposure to ionizing radiation , unlike radiation-induced cancer . It is distinct from acute radiation syndrome in that it occurs at dose rates low enough to permit natural repair mechanisms to compete with the radiation damage during the exposure period . Dose rates high enough to cause the acute form ( > ~ 0.1 Gy/h ) are fatal long before onset of the chronic form . The lower threshold for chronic radiation syndrome is between 0.7 and 1.5 Gy , at dose rates above 0.1 Gy/yr . This condition is primarily known from the Kyshtym disaster , where 66 cases were diagnosed . It has received little mention in Western literature ; but see the ICRP ’s 2012 Statement
Kyshtym disaster
Kyshtym disaster
Chronic radiation syndrome