Jing M. Chen
The United Nations Scientific Committee on the Effects of Atomic Radiation (in short UNSCEAR) has regularly updated its evaluation on population exposure levels to ionizing radiation since 1958. With more broadly available data and modified analysis methodologies, the Scientific Committee published its most recently updated evaluation of public exposure to ionizing radiation, the UNSCEAR 2024 Report, Annex B. The annex was based mainly on data submitted by 61 United Nations Member States to the UNSCEAR Public Exposure Survey for the period 2007–2020 and compiled from published peer reviewed literature and international organizations. The updated evaluation provided a clearer and more globally representative picture of the radiation doses that people receive in their daily lives from both natural and human-made sources of radiation. It demonstrated that natural background radiation remains the dominant source of public exposure, and confirmed that the public exposure to human-made sources is only a small portion of the public exposure to ionizing radiation and this small portion continues to decline. The major limitation of current evaluation was the low rate of participation by United Nations Member States in providing national representative data, and lack of discharge data from facilities and activities of industries involving naturally occurring radioactive materials. As the assessment of the worldwide public exposure is a complex task, there is the need to continue the development of data inventories and methodologies, and the collaboration with international organizations.