A new study has found radiation exposure levels in homes, workplaces, food and medical treatments in Ireland have risen slightly over the past six years.
But the research by the Radiological Protection Institute of Ireland also found that fallout from nuclear accidents, weapons tests and discharges of radioactive waste remain at very low levels.
The institute's latest report shows the average annual dose a person in Ireland is exposed to is up slightly compared to six years ago.
Almost two thirds of the exposure comes from natural gases, particularly radon, which can build up to dangerous levels in homes in prone areas.
Food has both naturally and artificially occurring radiation in it, and accounts for 7% of exposure, a slight increase on the last study.
Exposure levels from beneficial medical treatments have also risen slightly and are the largest contributor to man-made sources.
The report also says fallout from nuclear accidents, weapons tests and discharges of radioactive waste remain at very low levels of less than 1%.
Overall average radiation exposure levels in Ireland are among the highest in Europe, mostly because of increased levels of radon.