25 February 2026
Scientists at the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) have contributed to a new international report that finds natural sources continue to make up the majority of the global population’s exposure to ionising radiation.
The findings are published in the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) latest scientific annex, ‘Evaluation of public exposure to ionizing radiation’, providing the most comprehensive global assessment to date of radiation doses received by the public from natural and artificial sources.
One of the lead writers was ARPANSA’s public and occupational exposures assistant director Dr Cameron Lawrence.
He says the new report estimates that the worldwide average annual effective dose from natural sources is approximately 3.0 millisieverts (mSv).
‘In Australia our background radiation is much lower than the international average, at about 1.7 mSv per year,’ Dr Lawrence said.
Dr Lawrence’s colleague, Brendan Tate, contributed to the UNSCEAR report as a member of one of the task groups.
‘Inhalation of radon, thoron, and their decay products remain the major contributors to human exposure,’ Mr Tate said.
‘With the exception of medical exposure, exposure from other artificial sources, such as the nuclear fuel cycle, global fallout and consumer products are minor.'
The increase from the previously reported global average of 2.4 mSv by UNSCEAR in 2008 reflects more data being available and better calculation methods than an actual rise in radiation levels.
Australia is one of 27 United Nations Member States that participate in UNSCEAR’s work.
As the Australian Government’s primary authority on radiation protection, ARPANSA supports international scientific collaboration to enhance protection of people and the environment.
To see what makes up Australia’s natural background radiation, go to this website: Ionising radiation and health.
