ABSTRACT
It is established that ionizing radiation is a potent mutagen and carcinogen that can induce somatic and heritable mutations, and neoplastic and certain non-neoplastic diseases; however, it is also used in the diagnosis and treatment of certain human diseases. Children are more sensitive to ionizing radiation on all criteria of radiation damage, including cancer, than adults. Also, the time interval between radiation exposure and death in children is longer than adults, which would increase the risk of expression of deleterious effects in children more than in adults.1,2 Growing use of x-raybased devices in the early diagnosis of human diseases has raised concerns about potential hazards of such procedures in increasing the risk of cancer, and somatic and heritable mutations in individuals receiving diagnostic doses of radiation. These risks also exist in radiation workers who are exposed to higher doses of ionizing radiation per year than non-radiation workers. The number of radiation workers has increased proportionally with increased diagnostic radiation procedures. In 2008, it was estimated that over 60 million computed tomography (CT) scans were performed in the United States.3 This estimate did not include other diagnostic procedures such as chest x-rays, dental x-rays, uoroscopic imaging, positron emission tomography (PET), and other nuclear medicine scans. Therefore, it is likely that many more patients were exposed to diagnostic doses of radiation than the current estimates. Because of the potential health hazards of low doses of radiation, developing an effective radioprotective strategy that involves both physical and biological protection methods against potential damage from low doses of radiation has become an urgent issue for the present and future generations.
