and 2014). In 2015, IRSN developed an aid baptised CIDRRE (French acronym for “Calculation of the impact of radioactive discharges into wastewater networks”), which enables nuclear medicine departments and research laboratories to estimate, with reasonably penalising assumptions, conservative dose values for the sewage system workers based on the activities administered by the departments. Situations of exposure of waste treatment personnel associated with the handing of radioactive waste from nuclear medicine healthcare services or produced by patients at home are exceptional and of very limited scale, even if radiation portal monitors do get activated from time to time at the entrance to waste treatment facilities (see point 2.3.3.4). With regard to the in utero exposure of the embryo or foetus, less than a quarter of the Significant Radiation Protection Events (ESRs) notified to ASN each year concern the exposure of women unaware of their pregnancy (see point 2.7). The doses delivered to the uterus by imaging examinations are usually less than 100 milligrays (mGy), a value below which no increase in malformations or reduction in intellectual quotient has been detected to date in comparison with spontaneous risks (estimated at 3%)(3). In nuclear medicine, a source of radionuclides is administered to the patient. This source of ionising radiation can lead to exposure of the patients’ carers and conforters. To control this type of exposure, the regulations have introduced the notion of “dose constraints”. To verify compliance with these dose constraints, equivalent ambient dose rate measurements can be taken before discharging a patient who has undergone a nuclear medicine procedure. In clinical practice, nuclear medicine departments make the discharging of patients having received a high activity (therapeutic application) conditional on an equivalent dose rate of about 20 microsieverts per hour (µSv/h) at a distance of 1 m (recommendations of the GPRP in Medical Applications – October 2017). It is usually necessary to hospitalise the patient in a radiation-proof room while waiting for the activity to decay. The introduction of new RPDs will lead to the updating of the instructions for the carers and family circle. The GPRP is currently working on this (see chapter 2). 1.2.4 The environmental impact In nuclear medicine, the radioactive sources administered to the patients will undergo physical decay (period of time stemming from the physical-chemical properties of the sources) but also biological elimination (resulting from the biological metabolism, as with any medication). Patients having received an injection eliminate part of the administered radioactivity, mainly via the urinary tract. Nuclear medicine departments are designed and organised for the collection, storage and disposal of the radioactive waste and effluents produced in the facility, particularly the radionuclides contained in patients’ urine (see point 2.3.2), and are required to draw up an Effluents and Waste Management Plan (EWMP) detailing the collection, management and disposal arrangements. In addition, a discharge monitoring system must be put in place. The environmental impact of using ionising radiation for medical purposes is measured by the environmental radiological monitoring ensured by IRSN (see chapter 3). The measurement results are approximately equivalent to the background radiation. Radioactivity measurements in major rivers or wastewater treatment plants of large towns occasionally reveal the presence of artificial radionuclides used in nuclear medicine (iodine-131, for example; assessment of the radiological condition of the French environment from 2018 to 2020). However, no trace of these 3. IRSN Report No. 2021‑00848 on the estimation of the impact on the public of effluents containing radionuclides coming from nuclear medicine departments and research laboratories. radionuclides has been detected in water intended for human consumption (see chapter 1). Furthermore, the bibliographic study conducted by IRSN(3) in 2021 reveals a low radiological impact on the public of the radioactive discharges from nuclear medicine departments into the sewage systems (from its analysis of two French studies, IRSN estimates that the exposure of people living near wastewater treatment plants is less than 1 microsievert per year – μSv/year). 1.3 REGULATIONS 1.3.1 General regulations Protection of the personnel working in facilities that use ionising radiation for medical purposes is governed by the provisions of the Labour Code (Articles R. 4451‑1 to R. 4451‑135). In order to protect the public and the workers, the facilities that use MDs emitting ionising radiation must also satisfy the technical rules defined in the ASN resolutions (see technical rules described in points 2.1.2, 2.2.2, 2.3.2, 2.4.2, 2.5.2 and 2.6.2 of this chapter). The monitoring of sources (radioactive sources including RPDs, devices emitting ionising radiation, particle accelerators) is subject to specific rules figuring in the Public Health Code (Articles R. 1333‑152 to R. 1333‑164). These rules concern the acquisition, distribution, import, export, sale, transfer, recovery and disposal of the sources. If the sources are not exempted, they must be notified, registered or licensed, depending on their nature. The sources are inventoried, then taken back when expired, and they can be subject to financial guarantees to ensure their recovery by the supplier. 1.3.2 Radiopharmaceutical drugs and medical devices The radionuclides used in nuclear medicine can be classified in two categories: ∙ the RPDs, subject to obtaining a Marketing Authorisation (MA), issued by either the French Health Products Safety Agency (ANSM) or the European Medicines Agency (EMA); ∙ the MDs that require the manufacturer to place a “CE” marking on them in order to be put on the market in European Union (EU) member countries or parties to the agreement with the European Economic Community (e.g. implantable MD, such as the microspheres marked with yttrium-90). Pending the obtaining of an MA, and to allow early access to medicines for patients suffering from serious or rare diseases, derogation processes have proliferated in France over the last twenty years. In order to simplify and harmonise these different processes, a reform of the access to medicines by derogation was implemented on 1 July 2021 (Decree 2021-869 of 30 June 2021). This reform, which aims to “allow even faster access to these medicines for patients at a therapeutic dead-end”, replaces the six authorisation systems by two conditions of access, namely compassionate access and early access. The MDs emitting ionising radiation (electrical X-ray generators and particle accelerators) used in nuclear-based medical activities must meet the essential requirements defined in the Public Health Code (Articles R. 5211-12 to R. 5211-24). The “CE” marking, which certifies conformity with these essential requirements, is mandatory. Further to technological developments, the Order of 15 March 2010 laying down the essential requirements applicable 208 ASN Report on the state of nuclear safety and radiation protection in France in 2023 • 07 • Medical uses of ionising radiation
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