Estimated collective effective dose to the population from X-ray and nuclear medicine examinations in Finland.

The collective effective doses to the population from X-ray and nuclear medicine (NM) examinations in Finland in 2008 and 2009, respectively, were estimated. The estimated collective effective dose per inhabitant was 0.45 mSv from X-ray examinations and 0.03 mSv from NM examinations. The collective effective doses per inhabitant have not changed substantially during the last 10 y. However, proportional dose due to CT examinations has increased from 50 % in 2005 to 58 % in 2009 of the total collective effective dose from all X-ray examinations and proportional dose of PET examinations from 7 to 13 % of the total collective effective dose from NM examinations. The collective effective dose from conventional plain radiography was over 20 % higher when estimated using the new (ICRP 103) tissue weighting factors than that obtained using the old (ICRP 60) tissue weighting factors.