Occupational radiation exposure of health professionals and cancer risk assessment for Lithuanian nuclear medicine workers

Occupational exposure to radiation among health workers: Genome integrity and predictors of exposure

The current study aimed to investigate genomic instabilities in healthcare workers who may experience varying levels of radiation exposure through various radiological procedures. It also sought to determine if factors related to the work environment and dosimeter reading could effectively explain the observed genomic instabilities. Utilizing the cytokinesis-block micronucleus assay (CBMN) on peripheral blood lymphocytes, we assessed a spectrum of genomic aberrations, including nucleoplasmic bridge (NPB), nuclear budding (NBUD), micronucleus (MN) formation, and total DNA damage (TDD). The study uncovered a statistically significant increase in the occurrence of distinct DNA anomalies among radiology workers (with a significance level of P < 0.0001 for all measurements). Notably, parameters such as total working hours, average work duration, and time spent in projection radiography exhibited significant correlations with MN and TDD levels in these workers. The dosimeter readings demonstrated a positive correlation with the frequency of NPB and NBUD, indicating a substantial association between radiation exposure and these two genomic anomalies. Our multivariable models identified the time spent in projection radiography as a promising parameter for explaining the overall genomic instability observed in these professionals. Thus, while dosimeters alone may not fully explain elevated total DNA damage, intrinsic work environment factors hold potential in indicating exposure levels for these individuals, providing a complementary approach to monitoring.

Evaluation of personal dose equivalents during positron emission tomography and computed tomography imaging

This study aimed to evaluate the annual occupational radiation exposure of technologists during PET/CT imaging in 2020 and 2021. Eleven nuclear medicine technologists were monitored at the PET/CT department. The personal dose equivalents (PDEs) for staff members, measured in terms of Hp (10) and Hp (0.07), were assessed annually, considering both deep and surface doses. PDEs were quantified using a thermoluminescent detector (LiF:Mg:Ti)). The average and range of PDEs and extremity doses (mSv) for the technologists were as follows: 4.5 (0.1-13.4) for Hp (10), 4.63 (0.1-13.9) for Hp (0.07), and 2.5 (0.2-17.5) for extremity, respectively. The results indicated that staff members are exposed to high-energy gamma rays while preparing radiopharmaceuticals, injections, and image acquisition. Therefore, proper handling of radiopharmaceuticals and patient management during the acquisition of parameters are crucial for maintaining the occupational dose within the defined limit.

Trend and distribution analysis of occupational radiation exposure among medical practices in Chongqing, China (2008-2020)

The personal dose levels of medical radiation workers in Chongqing from 2008 to 2020 were investigated and analysed. The results showed that a total of 68 379 people were monitored from 2008 to 2020. The number of radiation workers increased year by year, and the number of female radiation workers increased rapidly. The monitoring data were analysed by Mann-Whitney test, Mann-Kendall test and Bonferroni method. The annual mean effective dose from 2008 to 2020 showed a decreasing trend (P < 0.0001). At the 5% significance level, six occupational categories showed a significant decreasing trend (P < 0.0001).The average annual effective dose for medical radiation workers in Chongqing in 2020 was 0.4482 mSv and 94.73% of radiation workers received annual doses less than the public dose limit (1 mSv). Personal dose monitoring results for most radiation workers were low. The protection of radiation workers in interventional radiology and nuclear medicine should be concerned.

Advances in TEE-Centric Intraprocedural Multimodal Image Guidance for Congenital and Structural Heart Disease

Percutaneous interventions are gaining rapid acceptance in cardiology and revolutionizing the treatment of structural heart disease (SHD). As new percutaneous procedures of SHD are being developed, their associated complexity and anatomical variability demand a high-resolution special understanding for intraprocedural image guidance. During the last decade, three-dimensional (3D) transesophageal echocardiography (TEE) has become one of the most accessed imaging methods for structural interventions. Although 3D-TEE can assess cardiac structures and functions in real-time, its limitations (e.g., limited field of view, image quality at a large depth, etc.) must be addressed for its universal adaptation, as well as to improve the quality of its imaging and interventions. This review aims to present the role of TEE in the intraprocedural guidance of percutaneous structural interventions. We also focus on the current and future developments required in a multimodal image integration process when using TEE to enhance the management of congenital and SHD treatments.

The potential advantages and workflow challenges of long axial field of view PET/CT

Recently developed Long (≥100 cm) axial field of view (AFOV) PET/CT scanners are capable of producing images with higher signal-to-noise ratio, or performing faster whole-body acquisitions, or scanning with lower radiation dose to the patient, compared with conventional PET/CT scanners. These benefits, which arise due to their substantially higher, by more than an order of magnitude, geometric efficiency, have been well described in the recent literature. The introduction of Long AFOV PET/CT technology into the clinic also has important implications for the design and workflow of PET/CT facilities and their effects on radiation exposure to staff and patients. Maximising the considerable benefits of this technology requires a thorough understanding of the relationships between these factors to optimise workflows while appropriately managing radiation exposure. This article reviews current knowledge on PET/CT facility design, workflows and their effects on radiation exposure, identifies gaps in the literature and discusses the challenges that need to be considered with the introduction of Long AFOV PET/CT into the clinic.

Abundance and cultivable bioaerosol transport from a municipal solid waste landfill area and its risks

Municipal solid waste (MSW) landfills, constituting the third largest anthropogenic sources of bioaerosols, are suspected to be one of the major contributors to adverse health outcomes. A regional modeling of aerosol trajectories based on wind-tunnel observations and on-site monitoring was newly-developed to uncover the impacts of a typical MSW landfill on ambient bioaerosol pollution. Results showed that the horizontal diffusion velocity of bioaerosols reached 4.33 times higher than the vertical velocity under surface calm winds. On-site monitoring revealed that the concentrations of particulate matter (PM) with a diameter of 10 μm were 3.05 times higher than those of PM1.0 in the 2.8-km downwind residential regions near the MSW landfill. With the increase in PM concentration, higher-abundance microorganisms were detected. A number of cultivable bacterial species (Micrococcus endophyticus, Micrococcus flavus, Bacillus sporothermodurans, Salmonella entericaserovar typhi, Rhodococcus hoagie, Blastococcups) and fungal species (Aspergillus niger, Penicillium, Microascus cirrosus, Cochliobolus, Stemphylium vesicarium) were identified in these bioaerosols. Furthermore, distinguished by transmission electron microscopy, a longer-range transported microorganism (E. coli) clinging onto suspended PM was observed, signifying higher exposure risks. Human health risk assessments demonstrate that the residents and occupational workers in the vicinity of MSW landfill endured atmospheric diffusion-induced bioaerosol exposure risks due to open dumping activities in MSW landfill. This study clearly indicates bioaerosol pollution from landfills, and people particularly living nearby the MSW facilities, must decrease outdoor activities during dusty days.

Whole-body radiation exposure in Trauma and Orthopaedic surgery

Aims

The use of fluoroscopy in orthopaedic surgery creates risk of radiation exposure to surgeons. Appropriate personal protective equipment (PPE) can help mitigate this. The primary aim of this study was to assess if current radiation protection in orthopaedic trauma is safe. The secondary aims were to describe normative data of radiation exposure during common orthopaedic procedures, evaluate ways to improve any deficits in protection, and validate the use of electronic personal dosimeters (EPDs) in assessing radiation dose in orthopaedic surgery.

Methods

Radiation exposure to surgeons during common orthopaedic trauma operations was prospectively assessed using EPDs and thermoluminescent dosimeters (TLDs). Normative data for each operation type were calculated and compared to recommended guidelines.

Results

Current PPE appears to mitigate more than 90% of ionizing radiation in orthopaedic fluoroscopic procedures. There is a higher exposure to the inner thigh during seated procedures. EPDs provided results for individual procedures.

Conclusion

PPE currently used by surgeons in orthopaedic trauma theatre adequately reduces radiation exposure to below recommended levels. Normative data per trauma case show specific anatomical areas of higher exposure, which may benefit from enhanced radiation protection. EPDs can be used to assess real-time radiation exposure in orthopaedic surgery. There may be a role in future medical wearables for orthopaedic surgeons. Cite this article: Bone Jt Open 2022;3(11):907–912.

Assessment of extremity exposure to technologists working manually with99mTc-labelled radiopharmaceuticals and with an automatic injection system for18F-FDG

The hands of nuclear medicine (NM) personnel involved in radiopharmaceutical preparation and administration can receive significant radiation doses. The dose distribution across the hand is nonuniform and the Hp(0.07) doses obtained by an individual passive ring dosimeter do not always present a real situation. The aim of this study was to assess the extremity exposure of NM workers working with^99mTc-labelled radiopharmaceuticals and with an automatic IRIDE (COMECER, Italy)¹⁸F-FDG injection system. Hp(0.07) doses were measured using calibrated thermoluminescent dosimeters-100 (TLD-100) and were read by a RIALTO TLD (NE Technology) reader. It was found that the most exposed parts of the hand during work with¹⁸F and^99mTc radionuclides are the fingertips of the thumb, index finger and middle finger. The maximum fingertip doses were 1.3-2.4 times higher compared with the doses from the typical monitoring position (base of the middle finger of the dominant hand). When working with^99mTc, the average hand doses were relatively high, i.e. 0.17 ± 0.04 and 0.37 ± 0.13 mSv Gbq^-1for the left and the right hand, respectively, during preparation, and 58 ± 20 and 53 ± 13µSv GBq^-1for the left and the right hand, respectively, during administration of^99mTc labelled radiopharmaceuticals. Meanwhile, the lowest doses were found for hands during administration of¹⁸F-FDG (average hand dose 28 ± 13µSv GBq^-1for the left hand and 28 ± 7µSv GBq^-1for the right hand), which shows the advantages of automated injection/infusion systems, thus implementation of automatic infusion/injection in hospitals could be an expedient way to optimize Hp(0.07) doses to NM workers.

Diagnostic and therapeutic radioisotopes in nuclear medicine: Determination of gamma-ray transmission factors and safety competencies of high-dense and transparent glassy shields

We present the findings of an extensive examination on newly designed CdO-rich and transparent glass shields for nuclear medicine facilities in lieu of traditional and unfavorable materials, such as lead and concrete. Gamma-ray transmission factors of newly designed glass shields are determined using a variety of diagnostic, therapeutic, and research radioisotopes, including 67Ga, 57Co, 111In, 201Tl, 99mTc, 51Cr, 131I, 58Co, 137Cs, 133Ba, and 60Co. A general-purpose Monte Carlo code MCNPX (version 2.7.0) is used to determine the attenuation parameters of different material thicknesses. Next, the findings are compared using a standard concrete shielding material. The results indicate that adding more CdO to the glass composition improves the overall gamma-ray attenuation properties. As a result, among the heavy and transparent glasses developed, the C40 sample containing 40% CdO exhibited the best gamma-ray absorption properties against all radioisotopes. Furthermore, the gamma-ray absorption characteristics of this created high-density glass were shown to be better to those of a standard and heavy concrete sample. It can be concluded that the newly developed CdO-rich and transparent glass sample may be used in medical radiation fields where the radioisotopes examined are used in daily clinical and research applications.

Multiple Assessments on the Gamma-Ray Protection Properties of Niobium-Doped Borotellurite Glasses: A Wide Range Investigation Using Monte Carlo Simulations

In this study, the monotonic effect of Ta2O5 and ZrO2 in some selected borotellurite glasses was investigated in terms of their impact on gamma-ray-shielding competencies. Accordingly, three niobium-reinforced borotellurite glasses (S1 : 75TeO2 + 15B2O3 + 10Nb2O5, S2 : 75TeO2 + 15B2O3 + 9Nb2O5 + 1Ta2O5, and S3 : 75TeO2 + 15B2O3 + 8Nb2O5 + 1Ta2O5 + 1ZrO2) were modelled in the general-purpose MCNPX Monte Carlo code. They have been defined as an attenuator sample between the point isotropic gamma-ray source and the detector in terms of determining their attenuation coefficients. To verify the MC results, attenuation coefficients were then compared with the Phy-X/PSD program data. Our findings clearly demonstrate that although some behavioral changes occurred in the shielding qualities, modest improvements occurred in the attenuation properties depending on the modifier variation and its magnitude. However, the replacement of 2% moles of Nb2O5 with 1% mole of Ta2O5 and 1% mole of ZrO2 provided significant improvements in both glass density and attenuation properties against gamma rays. Finally, the HVL values of the S3 sample were compared with some glass- and concrete-shielding materials and the S3 sample was reported for its outstanding properties. As a consequence of this investigation, it can be concluded that the indicated type of additive to be added to borotellurite glasses will provide some advantages, particularly when used in radiation fields, by increasing the shielding qualities moderately.

Thermally Controllable Decolorization of Reusable Radiochromic Complex of Polyvinyl Alcohol, Iodine and Silica Nanoparticles (PAISiN) Irradiated with γ-rays

Some medical and industry workers using ionizing radiation sources have potential risks of accidental high-dose exposure of their extremities, particularly their hands. While practical dosimeters suitable for on-site real-time monitoring of hand exposure are not yet available, they are desirable to be developed. Thus, the authors focused on the application of a reusable radiochromic complex composed of polyvinyl alcohol, iodide and silica nanoparticles, named “PAISiN”, and examined their dose responses and thermal stabilities of radiochromic reactions. Three PAISiN samples each were irradiated with 5, 10 and 20 Gy of 137Cs γ-rays, and time changes of the radiation-induced colors were observed at different temperatures: 20 °C (in a laboratory), 40 °C (in an oven) and 5.5 °C (in a refrigerator). It was confirmed that the PAISiN samples presented a red color that was easily detectable by the naked eyesight immediately after irradiation. The coloration was cleared within 24 h for 5 Gy irradiation at room temperature. The decolorization process was remarkably accelerated at 40 °C; it was erased in just 2 h. In contrast, storing in the refrigerator (5.5 °C) kept the color persistently for at least 4 days. These findings indicate that we could flexibly control the decolorization process of PAISiN in accordance with the objective of radiation monitoring.

Tungsten-Based Hybrid Composite Shield for Medical Radioisotope Defense

The shielding performance of shielding clothing is typically improved by increasing the shielding material content, but this lowers the tensile strength of the material. The weight and wearability of the shielding suit are also adversely affected. Important considerations when developing shielding fabric are thickness and flexibility to allow the wearer sufficient mobility. Insufficient thickness lowers the shielding performance, whereas excessive thickness decreases the flexibility of the garment. This study aimed to develop a composite shield that reproduces the shielding performance and meets the flexibility of the process technology. The new shield was manufactured by combining two layers: the shielding fabric fabricated from tungsten wire and a shielding sheet produced by mixing a polymer (PDMS) with tungsten powder. These two shields were bonded to develop a double hybrid composite. Compared with the existing shielding sheet (produced from lead equivalent of 0.55 mmPb), the shielding performance of the hybrid composite shield improved by approximately 17% on average and the tensile strength was 53% higher. The hybrid composite shield has a thickness of 1.35 ± 0.02 mm and delivers the same shielding performance as the lead equivalent. The new hybrid composite shield offers higher wearer mobility while shielding against radiation exposure in medical institutions.

Cultural adaptation and updating of the Risk assessment and management of exposure of health care workers in the context of covid-19 questionnaire

Objective:

to translate and culturally adapt the Risk assessment and management of exposure of health care workers in the context of covid-19 questionnaire to the Brazilian context and to develop and evaluate a sociodemographic and occupational characterization questionnaire to compose the adapted questionnaire.

Method:

five stages were conducted to adapt the Risk assessment and management of exposure of health care workers in the context of covid-19 questionnaire, namely: translation, synthesis of the translations, evaluation by a committee of judges, back translation and pre-test. As for the complementary questionnaire, it was elaborated and evaluated by a committee of judges and a pre-test was carried out.

Results:

the questionnaires were validated and the pre-test stage was conducted with health workers and students.

Conclusion:

the final version adapted to the Brazilian context was called Questionário de avaliação de risco e gestão da exposição de trabalhadores e estudantes de saúde no contexto da covid-19 and is available for use, together with the final version of the Sociodemographic and occupational questionnaire: Risk assessment and management of exposure of health care workers and students in the context of covid-19. These questionnaires may assist in mitigating the risks of infection, illness and death of health workers and students due to covid-19.

EVALUATION OF ANNUAL RADIATION EXPOSURE OF STAFF IN A CARDIAC CATHETERIZATION DEPARTMENT IN SAUDI ARABIA

The objective of this study is to estimate the annual effective dose for cardiologists and nurses by measuring Hp(10) and Hp(0.07) during cardiac catheterization procedures. A total of 16 staffs members were working in interventional cardiology during 1 year at a tertiary hospital. The occupational dose was measured using calibrated thermo-luminescent dosemeters (TLD-100, LiF:Mg,Ti). The overall mean and range of the annual Hp(10) and Hp(0.07) (mSv) for cardiologists were 3.7 (0.13-14.5) and 3.2 (0.21-14.7), respectively. Cardiologists were frequently exposed to higher doses compared with nurses and technologists. The exposure showed wide variations, which depend on occupation and workload. Staff is adhered to radiation protection guidelines regarding shielding the trunk, thyroid shield, thus appropriately protected. Lens dose measurement is recommended to ensure that dose limit is not exceeded.

Occupational exposure and radiobiological risk from thyroid radioiodine therapy in Saudi Arabia

Worldwide, thyroid cancer accounts for some 10% of total cancer incidence, most markedly for females. Thyroid cancer radiotherapy, typically using 131I (T1/2 8.02 days; β- max energy 606 keV, branching ratio 89.9%), is widely adopted as an adjunct to surgery or to treat inoperable cancer and hyperthyroidism. With staff potentially receiving significant doses during source preparation and administration, radiation protection and safety assessment are required in ensuring practice complies with international guidelines. The present study, concerning a total of 206 patient radioiodine therapies carried out at King Faisal Specialist Hospital and Research Center over a 6-month period, seeks to evaluate patient and occupational exposures during hospitalization, measuring ambient doses and estimating radiation risk. Using calibrated survey meters, patient exposure dose-rate estimates were obtained at a distance of 30-, 100- and 300 cm from the neck region of each patient. Occupational and ambient doses were measured using calibrated thermoluminescent dosimeters. The mean and range of administered activity (AA, in MBq) for the thyroid cancer and hyperthyroidism treatment groups were 4244 ± 2021 (1669-8066), 1507.9 ± 324.1 (977.9-1836.9), respectively. The mean annual occupational doses were 1.2 mSv, that for ambient doses outside of the isolation room corridors were found to be 0.2 mSv, while ambient doses at the nursing station were below the lower limit of detection. Exposures to staff from patients being treated for thyroid cancer were less compared to hyperthyroidism patients. With a well-defined protocol, also complying with international safety requirements, occupational exposures were found to be relatively high, greater than most reported in previous studies.

Health-related quality of life among radiology technicians in Turkish hospitals: a cross sectional study

BACKGROUND

Health related quality of life (HRQoL), despite its potential bi-directional interaction with occupational risks, has not been extensively addressed among radiology technicians.

OBJECTIVE

To evaluate HRQoL among radiology technicians in relation to sociodemographic and occupational factors.

METHODS

A total of 115 radiology technicians who were employed in three big hospitals located in Istanbul province were included on a voluntary basis in this cross sectional questionnaire-based study conducted between June 2019 and August 2019. The questionnaire form elicited items on socio-demographic characteristics, occupational characteristics and the 36-item Short-form Health Survey (SF-36), respectively.

RESULTS

Overall, 94.8% of technicians confirmed previous training on radiation protection and safety, while 92.2% noted distrust in their knowledge on radiation protection and patient dosage. In addition, 47.8% of technicians noted seldom use of radiation protection measures and 55.7% noted distrust in reliability of radiation exposure measurements. The multiple regression analysis revealed that older age, female gender, working at a university hospital and seldom use of protection significantly predicted poor HRQoL (p = 0.042 to 0.001), while working in interventional radiology and having trust in radiation exposure measurements predicted better HRQoL (p = 0.006 to 0.001) in terms of certain domains.

CONCLUSION

In conclusion, our findings revealed lack of trust in current self-knowledge on radiation protection and safety by majority of radiology technicians and seldom use of radiation protection measures by half of them, despite previously trained on radiation protection and safety. Certain occupational factors and factors related to radiation protection and safety were also amongst the significant determinants of poor HRQoL.

Job satisfaction and perceived stress among radiology technicians: a questionnaire survey in relation to sociodemographic and occupational risk factors

PURPOSE

To evaluate job satisfaction and perceived stress among radiology technicians in relation to sociodemographic and occupational risk factors.

METHODS

A total of 207 radiology technicians were included in this questionnaire-based study. The questionnaire elicited items on sociodemographic and occupational characteristics along with Minnesota Satisfaction Questionnaire (MSQ) and Perceived Stress (PSS) scales to assess job satisfaction and the perceived stress, respectively.

RESULTS

Multivariate analysis revealed that more years in practice (B: - 4.80, BCa 95% CI - 7.26 to - 2.47), being uncomfortable with working in a radiation environment (B: - 6.30, BCa 95% CI - 9.62 to - 2.61) and the use of public transport to get to work (B: - 3.62, BCa 95% CI - 6.53 to - 1.03) were significant predictors of poorer job satisfaction, whereas break time (B: 8.54, BCa 95% CI 4.63-12.14) and following scientific literature (B: 8.32, BCa 95% CI 3.37-12.89) significantly predicted the better job satisfaction. Being satisfied with the current job (p < 0.015) and high-income class (p = 0.005) were associated with lower perceived stress levels, while higher perceived stress level (B: - 0.48, BCa 95% CI - 0.66 to - 0.32) was also a significant predictor of poorer job satisfaction.

CONCLUSION

In conclusion, our findings revealed job satisfaction and perceived stress of radiology technicians to be at moderate levels and to be negatively correlated with each other. Our findings emphasize the importance of continuing education, in-service refresh training and continuing practice of regularly updating self-knowledge along with balance workload, income and safety at work to improve job satisfaction among radiology technicians.

Occupational exposure in a PET/CT facility using two different automatic infusion systems

PURPOSE

The aim of this study was to measure the occupational exposure using active personal dosimeters (APD) in the PET/CT department at different stages of the operation chain i.e. radiopharmaceutical arrival, activity preparation, dispensing, injection, patient positioning, discharge and compare the radiation exposure doses received using two automatic injection/infusion systems. This paper also reflects optimization processes that were performed to reduce occupational exposure.

METHODS

Measured APD data were analysed for medical physicists, radiology technologists and administrative staff from 2014 till 2018. For dispensing and injecting ¹⁸F-FDG, the automatic infusion/injection system IRIDE (Comecer, Italy) or the automatic fractionator ALTHEA (Comecer, Italy) with wireless injection system WIS (Comecer, Italy) were used. Radiation exposure optimization methods were applied during the data collection period (installation of the transport port, patient management, APD alarm threshold and etc.).

RESULTS

Radiology technologists who perform injection procedures, regardless of the automatic infusion system, received the highest radiation exposure dose. The average doses to the radiology technologists per one study were 1.72 ± 0.33 μSv and 1.16 ± 0.11 μSv with ALTHEA/WIS and IRIDE system, respectively. The average dose for accompanying the patient to the PET/CT scanner and scan procedure was 0.52 ± 0.07 μSv. For the medical physicists, the average dose was 0.29 ± 0.09 µSv. The measured dose for administrative staff was 0.30 ± 0.15 μSv.

CONCLUSIONS

Occupational exposure can be effectively optimized by different means including staff monitoring with APD, implementation of radiation safety culture and the usage of automatic infusion systems.