Radiation Exposure Of Workers Research Articles

Automated Injectors versus Manual Administration: A Comparative Analysis of Radiation Exposure Reduction in 18F-FDG Delivery

Abstract Background Despite the presence of safety protocols, the manual manipulation of radiopharmaceuticals continues to pose a significant occupational radiation risk. Health care professionals in nuclear medicine are at risk of radiation exposure, particularly to their hands and eyes. Despite existing protective measures, manual handling of radiopharmaceuticals remains a significant source of occupational radiation. Objective This study evaluates the effectiveness of automated injectors in reducing radiation exposure among health care workers during fluorine-18 fluorodeoxyglucose (18F-FDG) administrations, compared with traditional manual injection methods. Methods We assessed radiation exposure levels associated with manual versus automated 18F-FDG injection techniques using specialized dosimeters. Measurements focused on whole-body, extremity, and eye-lens radiation doses to evaluate the potential benefits of automation in minimizing exposure. Results Findings reveal that automated injectors significantly reduce radiation exposure, with decreases of 97.97 and 98.96% in left- and right-hand extremity doses, respectively, 43.24% in eye-lens dose, and 91.66% in whole-body dose compared with manual methods. Conclusion Automated injection systems offer considerable advantages in reducing health care worker radiation exposure in nuclear medicine. The substantial reduction in staff doses underscores the necessity of transitioning to such technology to promote safer clinical environments. This study highlights the critical role of automation in enhancing occupational safety standards within diagnostic radiology settings.

Deep learning-based gamma spectroscopic analysis considering multiple variables for in situ applications

Gamma spectroscopy in environments with fluctuating temperatures, magnetic fields, and radiation doses can lead to inaccurate material analysis and increased radiation exposure for workers. In this manuscript, we propose a deep learning model that reduces human intervention and remains robust against variables in uncontrolled environments, thereby enhancing the applicability of gamma spectroscopy in the field. The process of establishing a dataset to train, validate, and test the deep learning model involved simultaneous consideration of multiple variables, including gain shifts, detector energy resolutions, the number of mixed radioisotopes (RIs), mixed RI ratios, and statistical fluctuations of the spectrum. The model was trained using multi-label learning to perform RI identification and quantification simultaneously. Specifically, the RI quantification output of our model structure was designed to predict full-energy peak areas and mixed ratios for each RI. Highlighting the importance of a high-performance training dataset, the training and validation results of the gamma spectroscopy model were analyzed in depth. In the test results, organized by RI type and number of mixed RIs, the model demonstrated that following: even under complex conditions with multiple variables, all outcomes for RI identification and quantification were predicted with high accuracy and precision, exceeding 98%.

Occupational radiation exposure among medical personnel in university and general hospitals in Japan.

This study aimed to compare the occupational radiation exposure of medical workers between general hospitals and university hospitals. Radiation exposure data from three hospitals in Hiroshima city, including one university hospital and two general hospitals, were collected using personal dosimeters. Monthly radiation doses were analyzed, and the annual sum of radiation exposure dose was calculated for 538 subjects in general hospitals and 1224 subjects in the university hospital. To assess the impact of locality, additional data from Nagasaki University Hospital and Fukushima Medical University Hospital were included for comparative analysis. Professional affiliations, such as doctors, nurses, and radiological technologists, were considered in the evaluation. The study revealed slight but significant differences in radiation doses between general and university hospitals. In general hospitals, except for radiological technologists, a slightly higher radiation dose was observed compared to university hospitals. Despite the annual increase in the use of medical radiation, the majority of hospital workers in both settings adhered to safety guidelines, with occupational radiation exposure remaining below the limit of detection (LOD). Workers who involved in fluoroscopic procedure, whether at university or general hospitals, had higher radiation doses than those who did not. The study's primary conclusion is that workers in general hospitals experience a slight but significantly higher radiation dose and a lower percentage below the LOD compared to university hospitals. The observed difference is attributed to the greater workload at general hospitals than at university hospitals, and also may be due to the different nature of university hospital and general hospital. University hospitals, characterized by greater academic orientation, tend to benefit from comprehensive support systems, specialized expertise, and advanced technology, leading to more structured and regulated radiation control. These findings provide a basis for targeted interventions, improved safety protocols.

Improving Cytogenetic Surveillance in Radiology Workers Exposed to Low-Dose Radiation in Africa: A Call to Action

Radiation exposure is an occupational hazard for diagnostic and interventional radiology workers, potentially leading to chromosomal damage and increased cancer risk. This review explores the status of cytogenetic monitoring of radiation exposure among radiology workers in Africa. Monitoring of Radiation Exposure in Diagnostic and Interventional Radiology Workers in Ghana and Africa provides a crucial examination of radiation safety practices within the Ghanaian and Africa healthcare sector. We recovered existing literature on the cytogenetic surveillance conducted on radiology workers in Ghana and Africa stressing on the impact and/or significance of cytogenetic monitoring programmes. In these studies, mostly mathematical modeling and physical methods were used to estimate and extrapolate risks of exposure to ionizing radiation. Additionally, we discuss the challenges and opportunities for implementing cytogenetic monitoring programmes in Africa particularly Ghana and provide recommendations for future research and occupational health policies. This review attempts to bridge the gap between physical and biological dosimetry in surveillance studies. It addresses the significant gap in cytogenetic monitoring among diagnostic and interventional radiology workers in Africa. It highlights the importance of cytogenetic surveillance for early detection of radiation-induced genetic damage, assesses the current practices, and provides a recommendation and a roadmap for establishing robust monitoring programmes. This work would contribute significantly to the understanding of occupational radiation safety issues in the healthcare sector of Africa. It also offers a comprehensive examination of the challenges and opportunities in implementing cytogenetic monitoring programmes.

Central nervous system tumours and occupational ionising radiation exposure: a nested case–control study among the ORICAMs cohort of healthcare workers in France

ObjectiveThis study aimed at investigating the relationship between occupational exposure to external ionising radiation and central nervous system (CNS) tumours mortality in healthcare workers working in France.Design and settingThe Occupational...

Occupational Risks of Radiation Exposure to Cardiologists.

Invasive cardiologists are exposed to large amounts of ionizing radiation. This review aims to summarize the main occupational risks in a radiation-exposed cardiology practice. We carried out a literature review on the subject. The studies reviewed allowed us to list six main health risk categories possibly associated with radiation exposure among cardiologists: deoxyribonucleic acid (DNA) and biochemical damages; cancers; ocular manifestations; olfaction, vascular, and neuropsychological alterations; musculoskeletal problems; and reproductive risks. Our descriptive analysis demonstrates higher risks of DNA damage and lens opacities among radiation-exposed cardiology staff. Surveys and questionnaires have demonstrated a higher risk of musculoskeletal disease in exposed workers. Studies reported no difference in cancer frequency between radiation-exposed workers and controls. Changes in olfactory performance, neuropsychological aspects, and vascular changes have also been reported. Limited literature supports the security of continuing radiation-exposed work during pregnancy. Therefore, there is an urgent need to increase knowledge of the occupational risks of radiation exposure and to adopt technologies to reduce them.

A no-fault risk compensation approach for radiation risks incurred in space travel

In this paper we recommend an appropriate compensation approach should be established for fatality and disabilities that may occur due to space radiation exposures of government or industry workers. A brief review of compensation approaches for nuclear energy and nuclear weapons development workers in the United States and other countries is described. We then summarize issues in the application of probability of causation calculation and provide examples of probability of causation (PC) calculations for missions to the International Space Station and Earth's moon or for Mars exploration. The main focus of this paper follows with a recommendation of a no-fault approach to compensation with the creation of appropriate insurance policies funded by employers to cover all disabilities or fatality, without requiring proof of causation or restriction to conditions that imply causation. Importantly we propose that the compensation described should be managed by recourse to private insurers.

Assessment of occupational external radiation exposure of workers in the Southwest of Libya using portable NaI detector

In this study, gamma dose rates generated from the naturally occurring radioactive materials (NORM) were measured in the waste streams of a large scale and sludge onshore petroleum operations. Measurements conducted in this work involved: sludge recovery from separation tanks, sludge forming, NORM storage, scaling in oil tubulars, scaling in gas production and sedimentation in produced water evaporation ponds. Field work was carried out in many places of different terrain of an operation oil exploration and production in Murzuq basin in the Southwest of Libya. The radiation dose rates were measured using portable InSpector-1000. A total of 400 dose rates were acquired. The highest dose rate was 70 μSv/h acquired in sludge stored in barrels. The estimated mean annual equivalent doses in this field were in the range of 0.2–2.8 mSv/y in the first scenario, while in the second scenario the calculated mean annual equivalent doses were in the range of 0.04–0.68 mSv/y. It is assumed that workers may face various exposures in the field where measurements took place, considering the total annual effective dose to be 1.53 mSv/y. The main radioisotopes detected in these samples indicated by the display of the measuring device were 226Ra and 228Ra but detecting both radioisotopes in the same run is not achievable by using the display of the screen.

Evaluation of Worker Radiation Exposure during the Kori Unit 1 Steam Generator Dismantling Process

Kori Unit 1 was permanently shut down on June 18, 2017. Since then, Korea is actively preparing for the decommissioning of the nuclear power plant. Because decommissioning work is performed in a radioactive environment, worker radiation exposure is a significant consideration. In this study, worker radiation exposure is evaluated during the steam generator, one of the heavy components of nuclear power plant, dismantling process. A radiation evaluation for the dismantling process is performed using the code RESRAD-BUILD. A steam generator dismantling scenario and optimal cutting method are designed to evaluate worker radiation exposure, considering pipe dimensions, cutting tool speed, and experience in steam generator replacement. The evaluation results are derived for each work type and year. As a result of the evaluation, worker radiation exposure is 7.5 man-mSv at the year of planned decommissioning.

Assessment of Occupational Radiation Exposure for Radiotherapy Healthcare Workers at Kenyatta National Hospital Using Thermoluminescence Dosimeter LiF:Mg,Ti

Assessment of Occupational Radiation Exposure for Radiotherapy Healthcare Workers at Kenyatta National Hospital Using Thermoluminescence Dosimeter LiF:Mg,Ti

Radiation doses of medical radiation workers performing low-dose-rate brachytherapy with 198Au grains and 192Ir pins for patients with oral cancers.

Low-dose-rate brachytherapy (LDR-BT) with 198Au grains and 192Ir pins is an essential treatment option for oral cancer due to its high rate of local control and low invasiveness. However, the radiation exposure of medical radiation workers is concerning. Thus, we aimed to determine the radiation dose delivered to medical radiation workers during LDR-BT using 198Au grains and 192Ir pins for oral cancer. Thirty-two patients with oral cancer underwent 198Au grain interstitial LDR-BT between June 2016 and May 2023, and 23 patients with tongue cancer underwent 192Ir pin interstitial LDR-BT between March 2015 and November 2017 at our hospital. Dosimetry was performed by attaching a dosimeter to the chest pocket of the operator and assistant during 198Au grain or 192Ir pin LDR-BT. Since the operator also loads 198Au grains into the implantation device, the operator's radiation dose includes the dose received during this preparation. Mean radiation doses of the operators with 198Au grain and 192Ir pin LDR-BT were 165.8 and 211.2 μSv, respectively. Statistically significant differences between the radioactive sources of 198Au grain and 192Ir pin LDR-BT were observed (p = 0.0459). The mean radiation doses of the assistants with 198Au grain and 192Ir pin LDR-BT were 92.0 and 162.0 μSv, respectively. Statistically significant differences were observed between the radioactive sources of 198Au grains and 192Ir pin LDR-BT (p = 0.0003). Regarding radioactive source differences, 192Ir pin LDR-BT resulted in higher doses delivered to medical radiation workers than 198Au grain LDR-BT.

СРАВНЕНИЕ РАДИАЦИОННОЙ И ХИМИЧЕСКОЙ ТОКСИЧНОСТИ СОЕДИНЕНИЙ УРАНА НА ОСНОВЕ РАСЧЕТА ПО НОВЫМ БИОКИНЕТИЧЕСКИМ МОДЕЛЯМ МКРЗ

Purpose: Harmonization and improvement of the system for regulating the internal radiation exposure of workers and the basic requirements for ensuring radiation safety, taking into account the application of new international requirements and recommendations. Material and methods: The article presents a comparison of the radiation and chemical toxicity of uranium compounds, obtained on the basis of calculating the levels of inhalation intake and committed effective dose depending on the types of compounds F, M, F/M and M/S in the AMAD range from 0.3 to 20 μm for typical isotopic compositions of natural (NU), depleted (DU), low enriched (LEU) and highly enriched (HEU) uranium, which lead to the maximum permissible concentration of uranium in the kidneys. The calculations were carried out using new ICRP biokinetic models, which give more physiologically realistic representations of uptake and retention in organs and tissues, and excretion. Results: The dynamics of uranium activity in the kidneys was calculated for constant chronic inhalation intake over a 50-year period and for acute intake. It was shown that in case of chronic intake, the rate of accumulation of uranium in the kidneys, expressed in relative units, does not depend on the AMAD in the range from 0.3 to 20 μm and slightly depends on the types of compounds F, F/M, M and M/S, which include almost all chemical compounds of uranium. In case of acute intake, there is a rapid, within 1–3 days, an increase of uranium in the kidneys to a maximum value and then a gradual decrease to a value of 20 % of the maximum value in 20–60 days, depending on the type of compound F, M, F/M, M/S and AMAD in a wide range of values from 0.3 to 20 µm. To compare the radiation and chemical toxicity of uranium, the values of the committed effective dose were calculated, which is formed after intake of uranium aerosols of the types F, M, F/M and M/S and AMADs from 0.3 to 20 µm in an amount that creates the maximum concentration of uranium in the kidneys 0.3 µg/g for chronic intake and 3 µg/g for acute intake. The values of uranium intake per year in milligrams, which form the maximum concentration of uranium in the kidneys of 0.3 µg/g, in case of constant chronic intake of uranium aerosols, as well as the values of uranium intake in milligrams, which form the maximum concentration of uranium in the kidneys of 3 μg/g after a single intake of uranium aerosols in both case of the types F, M, F/M and M/S and AMAD in the range from 0.3 to 20 µm were calculated, which are evidently independent of the considered isotopic composition of the uranium. Conclusion: It is shown that chemical toxicity prevails over radiation toxicity for the types of uranium compounds F and F/M for all considered uranium isotopic composition, except for HEU; for the type of compound M it is the same for mixtures of NU and DU, and for the type M/S radiation toxicity prevails for all considered uranium isotopic composition. In case of chronic intake at committed effective dose exposure rate of several mSv per year, workers can suffer from the chemical toxicity of uranium when working with F and F/M compounds and isotope compositions of natural (NU), depleted (DU) and low enriched (LEU) uranium already after 1–2 years of work. In case of acute intake, the chemical toxicity of uranium should be taken as a criterion for limiting exposure for compounds F and F/M, and also partially M (for uranium isotope compositions of NU, DU and LEU), which can significantly, by tens and hundreds of times, reduce the permissible limit of uranium intake.

Radiation Protection of a 3D Computer Tomography Scanning Workplace for Logs-A Case Study.

Despite its undeniable advantages, the operation of a CT scanner also carries risks to human health. The CT scanner is a source of ionizing radiation, which also affects people in its surroundings. The aim of this paper is to quantify the radiation exposure of workers at a 3D CT wood scanning workplace and to determine a monitoring program based on measurements of ionizing radiation levels during the operation of a CT log scanner. The workplace is located in the Biotechnology Park of the National Forestry Centre. The ionizing radiation source is located in a protective cabin as a MICROTEC 3D CT machine with an X-ray lamp as X-ray source. The CT scanner is part of the 3D CT scanning line and its function is continuous quality scanning or detection of internal defects of the examined wood. The measurement of leakage radiation during scanning is performed with a metrologically verified meter. The measured quantity is the ambient dose equivalent rate H˙*10. The results of the measurements at the selected measurement sites have shown that, after installation of additional safety barriers, the CT scanner for the logs complies with the most strict criteria in terms of radiation protection. Workers present at the workplace during the operation of the CT scanner are not exposed to radiation higher than the background radiation level.

Measurement of Radiation Exposure of Hands and Fingers of Nuclear Medicine Personnel Using Innovative Low-Cost GM Based System

Pocket dosimeters are used commonly in Nuclear Medicine or radiology workers for daily dose measurement or during certain high radiation exposure procedures for short periods of time. These are expensive and have many maintenance costs. It may not be feasible to procure many at a time due to cost restraints. We designed a low cost remote dose monitoring device for measurement of radiation for short periods of time. Measuring device was constructed using micro Geiger Muller Counter. The micro-Geiger Counter with model no SBM21 was connected to high voltage circuit and the output signal was obtained. After this, output signal was sent it to Arduino circuit running custom code ESP8266 and readings was made on the mobile/ laptop application after connecting to Arduino circuit running custom code ESP8266 via internet. Readings were taken for short durations during certain periods. Readings were compared to the standard measuring instrument simultaneously. The tube was connected to their hands for hand exposure with a wire. Readings were recorded in the form of μSv/h or mSv/h. RESULT: Total readings were taken during various occasions while preparing (59) and dispensing (45) radioisotopes. During preparation of radiopharmaceuticals, average readings for 99mTc-Sestamibi[16 SAMPLE] (100mCi to 250mCi), 99mTc-MDP [21SAMPLE] (150-200mCi) and 99mTc-DTPA [22SAMPLES] (10-20mCi) were 1115 μSv/h, 3083 μSv/h and 453 μSv/h respectively. During dispensing of radiopharmaceuticals, average readings of total 15 sample each for 99mTc-Sestamibi (100mCi to 250mCi), 99mTc-MDP (150-200mCi) and 99mTc-DTPA (10-20mCi) were 351μSv/h, 209 μSv/h and 235 μSv/h respectively. It was feasible for the worker to fit the measuring device in their pocket while working. Conclusion: Our pilot study revealed accurate readings >95% of the times for short periods of time. Study designing, standardization of readings with more real time accuracy can make this method more reliable and is a low cost means to monitor short periods of radiation exposure for radiation workers.

Designing a boron nitride polyethylene composite for shielding neutrons

Neutrons are encountered in many different fields, including condensed matter physics, space exploration, nuclear power, and healthcare. Neutrons interacting with a biological target produce secondary charged particles that are damaging to human health. The most effective way to shield neutrons is to slow them to thermal energies and then capture the thermalized neutrons. These factors lead us to consider potential materials solutions for neutron shields that maximize the protection of humans while minimizing the shield mass and adapt well to modern additive manufacturing techniques. Using hexagonal boron nitride (hBN) as a capture medium and high-density polyethylene (HDPE) as a thermalization medium, we aim to design the optimal internal structure of h10BN/HDPE composites by minimizing the effective dose, which is a measure of the estimated radiation damage exposure for a human. Through Monte Carlo simulations in Geant4, we find that the optimal structure reduces the effective dose up to a factor of 72 over aluminum (Al) and up to a factor of 4 over HDPE; this is a significant improvement in shielding effectiveness that could dramatically reduce the radiation exposure of occupational workers.

A Study on the Construction of Cutting Scenario for Kori Unit 1 Bio-shield considering ALARA

Nuclear power plants are subjected to various processes during decommissioning, including cutting, decontamination, disposal, and treatment. The cutting of massive bio-shields is a significant step in the decommissioning process. Cutting is performed near the target structure, and during this process, workers are exposed to potential radioactive elements. However, studies considering worker exposure management during such cutting operations are limited. Furthermore, dismantling a nuclear power plant under certain circumstances may result in the unnecessary radiation exposure of workers and an increase in secondary waste generation. In this study, a cutting scenario was formulated considering the bio-shield as a representative structure. The specifications of a standard South Korean radioactive waste disposal drum were used as the basic conditions. Additionally, we explored the hot-to-cold and cold-to-hot methods, with and without the application of polishing during decontamination. For evaluating various scenarios, different cutting time points up to 30 years after permanent shutdown were considered, and cutting speeds of 1–10nullm2/h were applied to account for the variability and uncertainty attributable to the design output and specifications. The obtained results provide fundamental guidelines for establishing cutting methods suitable for large structures.

Role of Capillaroscopy in Early Diagnosis of Ionizing Radiation Damage in Healthcare Professionals.

Background and Objectives: Chronic ionizing radiation has biological effects on exposed healthcare workers, particularly on the skin. Capillaroscopy of the nail bed represents an easy, low cost, and non-invasive test to obtain information on the effects of chronic radiation exposure in healthcare workers. The aim of this study was to evaluate which capillaroscopic parameters are most associated with biological damage by chronic radiation exposure. Materials and Methods: We conducted a case-control study, in which cases were represented by healthcare workers exposed to ionizing radiations and controls by healthy subjects. We recorded anamnestic and personal data, including age and gender, before capillaroscopic examination of proximal nail folds of the fingers of both hands. Ten morphological qualitative/quantitative parameters were taken into consideration, assigning each of them a score on a scale from 0 to 3 (0 = no changes, 1 = <33% abnormal capillaries, 2 = 33-66% of abnormal capillaries, 3 = >66% of abnormal capillaries, for single magnification field at 200×). The parameters evaluated were: changes in the length, distribution and density of capillary loops, reduced visibility, decreased flow, visibility of the sub-papillary plexus, and presence of morphological atypia, such as ectasia, tortuosity, hemorrhage, and signs of neoangiogenesis. Results: We enrolled 20 cases and 20 controls. The two groups did not differ significantly for gender and age. Cases differed from controls in a statistically significant way for the following parameters: decreased capillary length (number of shortened capillaries) (p < 0.05), increased visibility of the subpapillary venous plexus (p < 0.05), tortuosity (p < 0.01), neoangiogenesis (p < 0.01), and ectasias (p < 0.001). Conclusions: We found that some capillaroscopic parameters, such as variability in length of capillaries, visibility of subpapillary venous plexus, presence of ectasias, tortuosity, and neoangiogenesis signs, are particularly associated with exposure to ionizing radiation in healthcare professionals. Alterations of these parameters may represent capillaroscopic clues of biological damage by chronic radiation exposure in healthcare professionals. Based on these observations, capillaroscopy may provide clinical data useful to the prevention and follow-up of radiation-exposed healthcare professionals.

Radiation safety and control in dental medical organizations

The authors analyzed the indicators of radiation exposure of dental medical workers of the Samara Region during medical procedures for the period from 2004 to 2019 in comparison with the quantitative dynamics of X-ray diagnostic studies. The main directions for improving the labor conditions of dental medical professionals when working with X-ray diagnostic equipment are de termined. The purpose of the study is to conduct a comparative analysis of indicators of the radiation exposure of dental medical workers of the Samara Region during medical procedures for the period from 2004 to 2019 in order to assess the radiation safety of personnel. The analytical work was carried out to assess the indicators of the average exposure dose in dental medical workers of the Samara Region during medical procedures according to the hygienic radiation certification of the ter ritory of the Samara Region for the period from 2004 to 2019. As part of this study, the number and demand for X-ray diagnostic procedures in dental medical institutions among the population were studied. A retrospective analysis of the dynamics of X-ray examinations and the values of the aver age individual dose of exposure of personnel working with X-ray dental devices in 10 large dental medical institutions of various forms of ownership in the territory of Samara and the Samara Region (S1‑S10) was carried out for the period from 2004 to 2019 based on the annual statistical reporting forms of the organization's hygienic radiation certificate. The decrease in radiation exposure is due to the replacement of outdated equipment with more modern devices, the transition from film types of examination to digital ones, and an increase in the personnel’s literacy in the field of radiation safety, which characterizes the improvement in the radiation safety indicators in dental workers in Samara and the Samara Region.

Occupational radiation exposure for dental radiation workers and diagnostic radiology workers in Albania

The development of dental radiology in Albania has been over a century. Medical imaging isessential to dental practice. X-rays examinations help dentists to diagnose, plan treatments and monitorboth treatments and lesion development. This study explored mainly the profile of dental radiation workerscomparing it with the diagnostic radiology workers and their occupational radiation exposure in Albaniafor the period 2016 to 2020. The assessment and analysis procedures of this study were carried out at thepersonal dosimetry laboratory, Institute of Applied Nuclear Physics. The total number of monitored dentalradiation workers increased from 39 in 2016 to 82 in 2020. The annual collective effective exposure dosefluctuated from 26.84man-Sv to 70.14man-Sv, and it showed an increasing trend. In addition, the averageannual effective exposure dose of total monitored dental radiation workers varied from 0.73mSv to0.87mSv. The total number of monitored diagnostic radiology workers increased from 196 in 2016 to 332in 2020. The annual collective effective exposure dose fluctuated from 240.99man-Sv to 358.03man-Sv,and it has showed an increasing trend. The average annual effective exposure dose of total monitoreddiagnostic radiology workers varied from 1.08 mSv to 1.40 mSv. The results of the measured annual dosewere well below the international recommended dose limit of 20 mSv.

Cohort profile: ORICAMs, a French cohort of medical workers exposed to low-dose ionizing radiation.

Medical personnel represent the largest group of workers occupationally exposed to ionizing radiation. Although the health risks associated with occupational exposure to low doses of ionizing radiation in the medical field have been investigated in several national cohorts, no study has been conducted in France to date. The ORICAMs (Occupational Radiation Induced Cancer in Medical staff) cohort is a nationwide French longitudinal cohort of medical workers exposed to ionizing radiation aiming to investigate the risk of radiation-associated cancer and non-cancer mortality. The ORICAMs cohort was set up in 2011 and includes all medical personnel monitored for ionizing radiation exposure with at least one dosimetric record in the SISERI database (the national registry for monitoring ionizing radiation exposure in workers) over the period 2002-2012. Causes of death were abstracted from death certificates and coded according to ICD-10. The follow-up ended on 31/12/2013. Standardized mortality ratios (SMRs) were calculated by cause of death to compare the mortality in the cohort to that in the French population, by gender, age group and calendar period. Among the 164,015 workers included in the cohort (60% women) a total of 1,358 deaths (892 in male and 466 in female) were reported. The observed number of all-cause deaths was significantly lower than expected based on national rates in both male (SMR = 0.35; 95% CI: 0.33, 0.38; ndeaths = 892) and female (SMR = 0.41; 95% CI: 0.38, 0.45; ndeaths = 466). This analysis leads to the conclusion that mortality in French workers exposed to medical radiation is significantly lower than the national reference rates. However, these results based on a comparative analysis with national rates may be impacted by the healthy worker effect towards low SMRs, and do not enable to establish a potential relationship between occupational exposure and mortality risk, even if we may suspect an impact of high SES of these professionals on the observed decreased mortality. Thus, further dose-response analyses based on individual ionizing radiation exposure and job's type will be conducted to characterize correlation between risk of cancer mortality and occupational exposure.