ASN Report 2017

58 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 01  - Nuclear activities: ionising radiation and health and environmental risks a top strategic priority in the 3rd National Plan for Radon Risk Management. This national plan for the 2016-2019 period is coordinated by ASN. 3.3 Doses received by patients In France, exposure for medical purposes represents the greatest part of the artificial exposures of the public to ionising radiation. This medical exposure has been increasing over the last thirty years or so due to the rise in the number of radiological examinations – and computed tomography examinations in particular, to the ageing of the population, and to the strategies implemented to ensure better patient care, particularly in the context of patient monitoring after cancer treatment and coronary diseases. It has been regularly reviewed by IRSN since 2002. The average effective dose per inhabitant resulting from diagnostic radiological examinations has been evaluated at 1.6 mSv for the year 2012 (IRSN report 2014) for some 81.8 million diagnostic procedures performed (74.6 million in 2007), i.e. 1,247 procedures for 1,000 inhabitants per year. It is to be noted that the individual exposure in 2012 is very varied. Thus, although about one third of the French population underwent at least one procedure (excluding dental procedures), 85% of that population was either not exposed or received doses of less than 1 mSv. The average individual effective dose increased by 23% between 2007 and  2012 (it was 1.3 mSv in 2007). Conventional radiology (54%), computed tomography (10.5%) and dental radiology (34%) account for the largest number of procedures. However, the contribution of computed tomography to the effective collective dose remains preponderant and more significant in 2012 (71%) than in 2007 (58%) whereas that of dental radiology remains very low (0.2%). In adolescents, conventional radiology and dental procedures are more numerous (1,020 and 1,220 procedures respectively for 1,000 individuals in 2012). Despite their frequency in this population, dental radiology procedures represent only 0.5% of the collective dose. Lastly, it is noteworthy that: ཛྷ ཛྷ in a sample of about 600,000 persons covered by health insurance, the analysis of the effective doses for these people who effectively underwent an examination shows that 70% of them received less than 1 mSv, 18% received between 1 and 10 mSv, 11%between10 and50 mSv and1%more than50 mSv. ཛྷ ཛྷ based on a sample of 100,000 children (1% of the French population), IRSN (2013 report) estimated that in 2010 one out of three children was exposed to ionising radiation for diagnostic purposes. The mean and median values for the effective dose are estimated at 0.65 mSv and 0.025 mSv respectively for all the children exposed. They are 5.7 mSv and 1.7 mSv respectively for children who have undergone at least one computed tomography procedure (1% of the population monitored). The substantial uncertainties in these studies with regard to the average effective dose values per type of procedure must nevertheless be taken into account, which justifies the need for progress in estimating doses in the next exposure study of the general population. IMAGING METHOD PROCEDURES COLLECTIVE EFFECTIVE DOSE NUMBERS % mSv % Conventional radiology (dentistry excluded) 44,175,500 54.0 18,069,200 17.7 Dental radiology 27,616,000 33.8 165,700 0.2 Computed Tomography 8,484,000 10.4 72,838,900 71.2 Diagnostic interventional radiology 377,000 0.5 3,196,400 3.1 Nuclear medicine 1,103,000 1.3 7,928,300 7.8 TOTAL 81,755,500 100.0 102,198,500 100.0 TABLE 3: Total number of procedures and associated collective effective dose for each imaging method (rounded values) in France in 2012 Source: IRSN 2014 ASN inspection in interventional radiology at the Strasbourg University Hospital, May 2017.