Invited Lecture 3.6

Abstract

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was established by the United Nations General Assembly in 1955, with the mandate to evaluate the latest scientific data on levels, effects, and risks of exposure to ionizing radiation for humans and the environment; and to provide an independent, objective and up-to-date scientific basis for radiation safety. The Committee's evaluations involve the identification of emerging trends and situations that may necessitate policy actions. These results are being utilized to establish international standards for radiation protection. The UNSCEAR 2020/2021 Report Volume I - Annex A: Evaluation of medical exposure to ionizing radiation concluded that medical procedures are the main source of artificial radiation exposure to the population. It is estimated that approximately 4.2 billion medical examinations are carried out worldwide each year, resulting in a collective effective dose of 4.2 million man-Sv. The average annual effective dose per person is 0.57 mSv. Significantly, although comprising just 10% of all examinations, computed tomography contributes to 62% of the collective dose. Interventional radiology's contribution to the collective dose has increased significantly, rising from 1% in 2008 to 8% currently. The global assessment was derived using a continuous model, based on the limited data received by the UNSCEAR Global Survey, to generate predictions for countries that did not provide data. The Committee is considering plans to initiate a new research survey. The Committee has stressed the importance of motivating United Nations Member States to fully participate in UNSCEAR surveys, and highlighted the importance of regular collection and publication of medical exposure data. The Committee also emphasized the importance of engaging with National Contact Persons and their alternates for broader data collection from Member States on medical, occupational, and public exposure to ionizing radiation. The involvement of national experts will ensure that the Committee's assessments of sources and magnitudes of exposure to ionizing radiation are of the highest quality.