Low dose radiation--a curse or a boon?

The increased use of nuclear technology has created fear in the minds of people regarding its possible adverse effects on living systems. This fear is heightened by press reports of nuclear fallouts and of high levels of natural background radiation in geographical areas in a number of countries. The International Commission on Radiological Protection and the United Nations Scientific Committee on the Effects of Atomic Radiation estimate the risk of cancer from high dose exposure to be 4.5% to 7.1% per sievert depending on the projection model used. However, when the exposure is to low dose background radiation, the available data does not show an increased risk. This is possibly due to the effectiveness of the inherent repair capacity of the living cell. These observations have given rise to the 'hormesis' hypothesis. Low dose radiation has in fact been found to be immunostimulatory and this is now being exploited as a possible treatment modality in cancer patients.