[Diagnostic value of whole blood cell parameters logistic regression model for radiation injury on radiation workers]

Objective: To explore the diagnostic value of whole blood cell parameters logistic regression model for radiation injury on radiation workers by comparing the differences of whole blood cell parameters between occupational radiation injury population and occupational health examination population. Methods: In February 2023, 184 radiation workers who received occupational health examinations in our hospital and occurrenced chromosome aberration from July 2021 to July 2022 were retrospectively selected as the radiation injury group. And other 184 radiation workers encountered in the same period without chromosome aberration occurrence were selected as the control group. Collected whole blood cell parameters from two groups of research subjects, conducted comparative analysis, constructed a logistic regression model, and evaluated the diagnostic value of the logistic regression model for radiation injury on radiation workers by receiver operating characteristic curve (ROC) and area under curve (AUC) . In addition, with the same standard, 60 radiation workers with chromosome aberration and 60 radiation workers without chromosome aberration from August 2022 to January 2023 were included in the validation queue to validate the logistic regression model. Results: Neu_X, Neu_Y, Neu_Z, Lym_X, Lym_Y, Lym_Z, Mon_X, Mon_Y, Mon_Z, Micro, MCHC in the radiation injury group were significantly higher than those in the control group, and the difference was statistically significant (P<0.05) . And MCV and Macro in the radiation injury group were lower than those in the control group, and the difference was statistically significant (P<0.05) . Moreover, logistic regression analysis showed that Lym_X, Lym_Y, Lym_Z, MCHC, Micro were all independent risk factors for diagnosing radiation injury on radiation workers (OR=1.08、1.02、0.99、1.06、51.32, P<0.05) . ROC curve analysis showed that the AUC, sensitivity, specificity, and accuracy of the logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro in diagnosing radiation injury on radiation workers were 0.80, 85.9%, 65.8% and 75.9% respectively. The validation queue verified the logistic regression model and the AUC, sensitivity, specificity, and accuracy of the logistic regression model were 0.80, 81.7%, 71.7% and 76.7% respectively, the model fitted well. Conclusion: Radiation damage can cause changes in multiple whole blood cell parameters of radiation workers. The logistic regression model based by Lym_X, Lym_Y, Lym_Z, MCHC and Micro showed good diagnosis ability and can be used for the screening of radiation injury on radiation workers.

[Analysis of the results of occupational health examination of radiation workers in Shaanxi Province]

Objective: To analyze the results of occupational health examinations of radiation workers in Shaanxi Province, and to provide basis and reference for effectively conduct occupational health monitoring. Methods: From April 2016 to January 2022, a questionnaire survey was conducted to collect the basic information on occupational health examinations of qualified radiation workers in Shaanxi Province from 2016 to 2021. Based on the abnormal rate of occupational health among radiation workers, 1018 people were randomly selected using a cluster stratified sampling method to analyze the occupational health examination results of different positions, types of work, gender, length of service, and exposure doses. Results: The chromosomal aberration rates of peripheral blood lymphocytes among radiation workers in Shaanxi Province from 2016 to 2021 were 0.26% (10/3876), 0.77% (27/3512), 0.16% (16/10153), 0.09% (13/14769), 0.10% (13/13399), and 0.12% (20/16671), respectively. The abnormal rates of thyroid ultrasound examination were 32.33% (150/464), 24.46% (649/2653), 55.24% (786/1423), 32.89% (888/2700), 35.69% (1475/4133), and 42.51% (1993/4688), respectively. There was a statistically significant difference in the abnormal rates among different years (P<0.05). The abnormal rate of renal function examination in male radiation workers was higher than that in females (P<0.05). Compared with non medical users, the abnormal rates of renal function, thyroid function, and blood routine examination in medical radiation workers were higher (P<0.05), and the abnormal rates of renal function, thyroid function, and blood routine examination in medical applications were higher than those in radiation diagnosis, nuclear medicine, and radiation therapy (P<0.05). The abnormal rates of electrocardiogram, chest X-ray, blood pressure, thyroid function, and blood routine increased with the length of service (P<0.05). The abnormal rates of blood pressure, liver function, kidney function, thyroid function, and blood routine examination increased with the exposure dose (P<0.05) . Conclusion: The occupational health status of radiation workers is not optimistic. Occupational health monitoring should be strengthened, especially interventional radiation diagnosis occupational health examination, as well as changes in the indicators of sensitive organs such as eye lens and thyroid, so as to ensure the health of radiation workers.

[Analysis of chromosome aberrations in peripheral blood lymphocyte of medical radiation workers in a tertiary hospital]

Objective: To analyze the level of chromosome aberration in lymphocytes of medical radiation workers and its influencing factors. Methods: From July to September 2020, 252 medical workers in a tertiary hospital were selected as the study subjects and 107 preserviceworkers were selected as the control group. The Chromosomal aberrations of peripheral blood lymphocytes were measured using conventional cytogenetic analysis method, and the differences were analyzed. Results: The frequencies of dicentric puls centric ring, total chromosome-type aberrations, and abnormal detection rate in the radiation group were significantly higher than those in the control group (Z=2.59, 3.74, 9.99, P<0.05). There was significant difference in the frequencies of dicentric plus centric ring and total chromosome-type aberrations among different types of work (χ(2)=8.59, 8.17, 11.39, P<0.05), and the frequencies of dicentric plus centric ring were significantly higher in the interventional radiology group than those in diagnostic radiology (χ(2)=2.90, P<0.05), While the rates of acentric fragment and total chromosome-type aberrations were significantly higher in the nuclear medicine group than those in diagnostic radiology (χ(2)=2.81, 3.19, P<0.05). The difference in the abnormal detection rate of chromosome aberrations between different types of work was statistically significant (P<0.05), and the rate in the interventional radiology group was significantly higher than that in the diagnostic radiology group (χ(2)=7.66, P<0.05). There was no significant difference in chromosome aberration level and abnormal detection rate among different working ages (P>0.05). Poisson regression analysis indicated that the type of work is a risk factor for chromosomal aberration [IRR=2.31 (nuclear medicine group), 1.66 (Radiation therapy), and 1.78 (interventional group) ; P<0.05]. Conclusion: Ionizing radiation causes certain radiation damage to medical radiology workers, and the frequencies of chromosome aberration in the radiation workers of nuclear medicine and interventional radiology groups are relatively high, so radiation protection should be strengthened to ensure the health of relevant workers.

Exposure to ionizing radiations and changes in blood cells and interleukin-6 in radiation workers

Long-term exposure to ionizing radiation (IR) can cause dire health consequences even less than the dose limits. Previous biomonitoring studies have focused more on complete blood counts (CBCs), with non-coherent results. In this study, we aimed to investigate the association between exposure to IR and cytokine interleukin-6 (IL-6) along with hematological parameters in Tabriz megacity's radiation workers. In this hospital-based study, blood samples were taken from 33 radiation workers (exposed group) and 34 non-radiation workers (control group) in 4 hospitals. Absorbed radiation dose was measured by a personal film badge dosimeter in radiation workers. The studied biomarkers and all of the selected covariates were measured and analyzed using adjusted multiple linear regression models. The exposed doses for all radiation workers were under the dose limits (overall mean = 1.18 mSv/year). However, there was a significant association between exposure to ionizing radiation and IL-6 (49.78 vs 36.17; t = 2.4; p = 0.02) and eosinophils (0.17 vs 0.14; t = 2.02; p = 0.049). The difference between the mean of the other biomarkers in radiation workers was not statistically significant compared to the control group. This study demonstrated that long-term exposure to ionizing radiation, even under the dose limits, is related to a significantly increased level of some blood biomarkers (Il-6 and eosinophil) that, in turn, can cause subsequent health effects such as cancer.

[Analysis on the health status of radiation workers in an international airport]

Objective: To understand the occupational health status of radiation workers at an international airport, and to provide basis and reference for relevant competent authorities to conduct scientific and effective occupational health monitoring. Methods: From July to August 2019, 246 radiation workers at an international airport were selected as the research subjects (observation group) , and their occupational health examination data were collected. At the same time, 210 radiation workers from a medical institution were selected as the control group. The occupational health examination results of the two groups were compared. And the differences in occupational health examination results of airport radiation workers among difference service age were analyzed. Results: Compared with the control group, the detection rates of ocular lens opacity (1.63%, 4/246) and abnormal blood glucose (4.07%, 10/246) in the observation group were lower, the detection rates of abnormal skin (11.79%, 29/246) , abnormal B-ultrasound of liver, gallbladder and spleen (75.61%, 186/246) and abnormal chest X-ray (5.28%, 13/246) were higher (P<0.05) . There were significant differences in the abnormal detection rates of skin, blood glucose, B-ultrasound of liver, gallbladder and spleen among airport radiation workers with different service age (P<0.05) . Abnormal chromosome of peripheral blood lymphocytes, abnormal chest X-ray were mainly distributed in the service age of ≥20 years. The abnormal rate of B-ultrasound of liver, gallbladder and spleen was higher in different working age groups. Conclusion: Long term low-dose irradiation will have a certain impact on the occupational health of airport radiation workers. The occupational health monitoring of relevant personnel should be strengthened to protect their occupational health.

[Analysis of occupational health status of radiation workers in Guangdong Province]

Objective: To discuss the effect of low-dose ionizing radiation on the health of radiation workers, and provide a basis for occupational health risk assessment of radiation workers. Methods: In January 2020, 3165 radiation workers who performed radiation occupational health examinations in Guangzhou Prevention and Treatment Hospital for Occupational Disease from January 2017 to December 2019 were selected as the research objects, and compared and analyzed the health status of radiation workers with different examination types (pre-job, in-job and off-job) , types of work, gender, and length of service. Results: The off-job occupational radiological health examination was rare at 2.3% (74/3165) . The abnormal detection rate of chest radiographs, renal function, thyroid function, and blood routine of the radiation workers in-job group was higher than that of the pre-job group (P<0.05) . No statistical difference was found in the abnormal detection rate of the examination items during the in-job group and the off-job group (P>0.05) . The blood routine abnormality detection rate of medical application group and industrial application group were higher than those of nuclear fuel group (P<0.05) . The abnormal detection rate of blood pressure and renal function of male radiation workers was higher than that of females, while the abnormal detection rate of blood routine of females was higher than that of males (P<0.05) . The abnormal detection rate of electrocardiogram, chest radiograph, blood pressure, renal function, thyroid function, and blood routine of radiation workers increased with increasing working age (P<0.05) . Conclusion: Occupational health status of radiation workers is not optimistic. Radiation occupational health monitoring should be strengthened, special attention should be paid to off-job radiation occupational health examination, focusing on the sensitive indicators of sensitive personnel, improving radiation protection conditions, and effectively protecting the occupational health of radiation workers.

Exposure to Radiation During Work Shifts and Working at Night Act as Occupational Stressors Alter Redox and Inflammatory Markers

BACKGROUND

Studies of breast cancer etiology suggest evidence that night shift working and occupational exposure to ionizing radiation (IR) are defined risk factors for breast cancer development. There are few studies to clarify neuroendocrine and inflammatory status and the possible consequences particularly in occupational exposure.

AIM OF THE STUDY

Our aim was to associate the redox and inflammatory biomarkers with either nightshift working or occupational radiation exposure, and to compare their levels between the two groups at Alexandria University Hospitals, Alexandria, Egypt.

METHODS

We included 150 female nurses at Alexandria University Hospitals: 50 nightshift workers, 50 radiation workers, and 50 dayshift workers as a control group (neither work nightly nor radiation workers). In morning serum sample (7 am), we measured the concentrations of serum melatonin, Cortisol, tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) by ELISA; malondialdehyde (MDA) and total antioxidant capacity (TAC) levels colorimetrically, and C-reactive protein (C-RP) levels by turbidimetric method.

RESULTS

Nightshift workers had significantly lower levels of melatonin and TAC, and higher levels of serum inflammatory markers and cortisol, than day shift control group of workers. Workers occupationally exposed to IR had significantly higher levels of serum melatonin, MDA and inflammatory markers, lower levels of serum cortisol, and lower TAC than day shift workers.

CONCLUSION

Occupational exposure to IR and working nightly alter circulating redox and inflammatory biomarkers.

The Efficacy of Periodic Complete Blood Count Tests in Evaluation of the Health Status of Radiation Workers in Iran: A Systematic Review

BACKGROUND

Periodic medical examinations of radiation workers are routinely conducted in many countries. Although low dose radiation (LDR) is not expected to cause a significant effect on blood count, the periodic examination usually includes reviewing the work history, general medical history, a physical examination and collecting a blood sample. Despite lymphocytes are the most sensitive cells to radiation, their counts do not show any significant change as long as the radiation level is less than a few hundreds of millisievert (mSv). In spite of this, in Iran, radiation workers, even those who work in diagnostic radiology departments, are regularly examined for blood count changes.

METHODS

After a detailed search in PubMed, ISI, Scopus, SID and Google Scholar, only 12 out of 650 articles matched our criteria. A review of these 12 reports was conducted. The full texts were fully reviewed by the authors.

RESULTS

The complete blood count (CBC) test has a very low efficacy in evaluation of the adverse health effects of ionizing radiation in radiation workers. Therefore, finding alternative methods with a higher efficacy is recommended.

CONCLUSION

CBC tests cannot be introduced as valid markers of potential radiation effects in most occupational exposures. Given this consideration, in periodic tests of radiation workers, cytogenetic tests can be the gold-standard method. In particular, due to its relatively low cost and good sensitivity and specificity, the dicentric assay can be promising. Moreover, the simple and rapid evaluation of micronuclei by fast automated scoring systems can be a good alternative for current low efficacy CBC tests.

Time-related study on external exposure dose of 2-deoxy-2-[F-18]fluoro-D-glucose PET for workers' safety

Time-course study of individual dose equivalents of 2-deoxy-2-[F-18]fluoro-D-glucose positron emission tomography (¹⁸F-FDG PET) was conducted in different hospital workers, and the daily work duties were analyzed. For the measurements, a semiconductor dosimeter was used. The values at intervals of 1 min and 1 h, the monthly cumulative and daily cumulative doses, and trend graphs were acquired with dedicated software and displayed on the reader. The following radiation workers with duties involving maximum external exposure work were included: doctors making diagnoses (4.8 μSv/procedure), nurses removing injection needles (3.1 μSv/procedure), pharmacists performing quality control tests (2.9 μSv/procedure), nuclear medicine technologists assisting patient positioning (6.5 μSv/procedure), and cyclotron engineers performing daily checks (13.4 μSv/procedure). The results of analysis of daily work duties revealed the influencing factors of external exposure dose. To reduce the external exposure dose, investigators should shorten the patient's contact time with the ¹⁸F-FDG source or patient tracer.

[Detection and Analysis of the peripheral lymphocytes micronucleus rate of radiation workers in a city]

Objective: To perform lymphocyte micronucleus analysis on radiation workers with long-term exposure to low doses ionizing radiation, Evaluate the health condition of radiation workers, and provide the evidence for strengthening surveillance of radiation workers. Methods: From January 1, 2013 to December 21, 2016, a statistical analysis and evaluation was conducted of the peripheral lymphocytes micronucleus rate in 5 901 radiation workers who had undergone medical examinations of employees at Chinese Academy of Medical Sciences Institute of Radiation Medicine. Results: The micronucleus rates in radiation workers of the on-job group were higher than the pre-job group (P<0.01) . Significant difference was found among the different sex (t=5.97) , different types (χ(2)=378.69) , different levels of work units (χ(2)=115.48) . Significant difference was found among the micronucleus rates of 672 radiation workers of the on-job group from 2013 to 2016 (χ(2)=92.57, P<0.01) . Conclusion: The peripheral lymphocytes micronucleus rate of radiation workers were significantly higher than non-contact workers. Significant increasing trend of micronucleus rates was noted among the radiation worker with increasing exposure time. The peripheral lymphocytes micronucleus rates of interventional therapy workers were highest. The peripheral lymphocytes micronucleus rates of Private hospitals workers were highest. This phenomenon deserves attention. Protection needs to be strengthened to ensure the health of radiation workers.

Radiological protection of foetuses and breast-fed children of occupationally exposed women in nuclear medicine - Challenges for hospitals

This paper describes issues of concern for protecting foetuses and breast-fed children of occupationally exposed women in nuclear medicine from unnecessary exposure of ionising radiation. The protection principle is to ensure the same level of protection for the foetus and child as for the general public. Therefore international radiation protection standards recommend a dose constraint of 1mSv to a foetus during the remaining time of pregnancy after it is known/declared and a yearly dose constraint of 1mSv to a breast-fed child. It is not self-evident how to guarantee this level of radiation protection. The exposure situation in nuclear medicine is complex. Exploring existing reported occupational exposure levels suggests great variability between work tasks and facilities. The standards and guidelines found give no detailed advice. Therefore each facility needs to systematically review external and internal exposure levels in order to plan appropriate protection measures and issue their own guidelines and rules. One strategy might be that each facility defines tasks that do not require any restrictions and lists such duties that are not suitable to do when pregnant or breastfeeding, taking also potential exposure levels into consideration. This paper gives examples of such types of work. Information to the staff about the necessity of declaring pregnancy or breastfeeding is of fundamental importance. The internal policies issued by the hospital management should make clear the basis for taking care of pregnant and breastfeeding employees.

Consecutive results of blood cell count and retrospective biodosimetry: useful tools of health protection regulation for radiation workers

BACKGROUND

Industrial radiography is known to be one of the most vulnerable lines of work among the range of different radiation work. According to the relevant law in Korea, every worker registered in this work should check their blood cell counts every year in addition to their thermoluminescent dosimeter (TLD) doses. Since the law was enacted, however, few follow-up studies have been carried out based on the obtained results.

OBJECTIVES

To ascertain the clinical usefulness of complete blood cell count (CBC) results and suggest a proper protocol of health protection for radiation workers.

METHODS

After reviewing all the consecutive results of CBC and TLD doses from radiation workers registered nationwide, we selected two groups of high-risk radiation workers, CBC-high risk (CBC-HR) and TLD-high risk (TLD-HR) groups. A control group of unexposed healthy adults was also included. We compared the absorbed doses calculated by cytogenetic biodosimetry among those three groups, and examined possible confounding factors for each group.

RESULTS

Both groups of high-risk radiation workers, CBC-HR and TLD-HR, showed higher chromosome aberrations than the control group. In the control group, previous medical history of a CT scan increased the frequency of chromosome aberrations. In contrast, the frequency of chromosome aberrations in the high-risk radiation workers was affected not by the previous CT history but only by the duration of their work.

CONCLUSIONS

We ascertain that reviewing consecutive results of blood cell counts and cytogenetic biodosimetry are useful complementary tools to TLD doses for health protection regulation. Several confounding factors including work duration and previous medical history need to be considered for the interpretation of biodosimetry results.