A recent National Council on Radiation Protection and Measurements (NCRP) report stated that the US population is now exposed to seven times more radiation each year from medical imaging exams than in 1980. In 2006, medical exposure constituted nearly half of the total radiation exposure of the US population from all sources.
The increase was primarily a result of the growth in the use of medical imaging procedures, explained Kenneth R. Kase, senior vice president of NCRP and chairman of the scientific committee that produced the report.
“The increase was due mostly to the higher utilization of computed tomography (CT) and nuclear medicine.These two imaging modalities alone contributed 36% of the total radiation exposure and 75% of the medical radiation exposure of the U.S. population.” The number of CT scans and nuclear medicine procedures performed in the US during 2006 was estimated to be 67 million and 18 million, respectively.
The NCRP Report No. 160, Ionizing Radiation Exposure of the Population of the US, provides a complete review of all radiation exposures for 2006.
Background radiation, which in 2006 contributed fully half of the total exposure, comes from natural radiation in soil and rocks, radon gas which seeps into homes and other buildings, plus radiation from space and radiation sources that are found
naturally within the human body.
Other small contributors of exposure to the US population included consumer products and activities, industrial and research uses and occupational tasks.
NCRP is working with some of its partners like the American College of Radiology (ACR), World Health Organization and others to address radiation exposure resulting from the significant growth in medical imaging and to ensure that referrals for procedures like CT and nuclear medicine are based on objective, medically relevant criteria (e.g., ACR appropriateness criteria).
This year marks the 80th anniversary of NCRP’s founding and the 45th anniversary of its charter from the U.S. Congress under Public Law 88-376.