Radium deposition in human brain tissue: A Geant4-DNA Monte Carlo toolkit study

NASA has encouraged studies on 226Ra deposition in the human brain to investigate the effects of exposure to alpha particles with high linear energy transfer, which could mimic some of the exposure astronauts face during space travel. However, this approach was criticized, noting that radium is a bone-seeker and accumulates in the skull, which means that the radiation dose from alpha particles emitted by 226Ra would be heavily concentrated in areas close to cranial bones rather than uniformly distributed throughout the brain. In the high background radiation areas of Ramsar, Iran, extremely high levels of 226Ra in soil contribute to a large proportion of the inhabitants' radiation exposure. A prospective study on Ramsar residents with a calcium-rich diet was conducted to improve the dose uniformity due to 226Ra throughout the cerebral and cerebellar parenchyma. The study found that exposure of the human brain to alpha particles did not significantly affect working memory but was significantly associated with increased reaction times. This finding is crucial because astronauts on deep space missions may face similar cognitive impairments due to exposure to high charge and energy particles. The current study was aimed to evaluate the validity of the terrestrial model using the Geant4 Monte Carlo toolkit to simulate the interactions of alpha particles and representative cosmic ray particles, acknowledging that these radiation types are only a subset of the complete space radiation environment.

Thyroid dysfunction following vaccination with COVID-19 vaccines: a basic review of the preliminary evidence

PURPOSE

The safety and efficacy of the several types of COVID-19 vaccines, including mRNA-based, viral vector-based, and inactivated vaccines, have been approved by WHO. The vaccines can confer protection against severe SARS-CoV-2 infection through induction of the anti-spike protein neutralizing antibodies. However, SARS-CoV-2 vaccines have been associated with very rare complications, such as thyroid disorders. This review was conducted to highlight main features of thyroid abnormalities following COVID-19 vaccination.

METHODS

A comprehensive search within electronic databases was performed to collect reports of thyroid disorders after vaccination with COVID-19 vaccines.

RESULTS

Among 83 reported cases including in this review, the most cases of thyroid abnormalities were observed after vaccination with mRNA-based vaccines (68.7%), followed by viral vector vaccines (15.7%) and 14.5% cases following inactivated vaccines. Subacute thyroiditis (SAT) was the most common COVID-19 vaccination-related thyroid disease, accounting for 60.2% of all cases, followed by Graves' disease (GD) with 25.3%. Moreover, some cases with focal painful thyroiditis (3.6%), silent thyroiditis (3.6%), concurrent GD and SAT (2.4%), thyroid eye disease (1.2%), overt hypothyroidism (1.2%), atypical subacute thyroiditis (1.2%), and painless thyroiditis with TPP (1.2%) were also reported. Overall, in 58.0% of SAT cases and in 61.9% of GD cases, the onset of the symptoms occurred following the first vaccine dose with a median of 10.0 days (ranged: 3-21 days) and 10.0 days (ranged: 1-60 days) after vaccination, respectively. Moreover, 40.0% of SAT patients and 38.1% of GD patients developed the symptoms after the second dose with a median of 10.5 days (ranged: 0.5-37 days) and 14.0 days (ranged: 2-35 days) after vaccination, respectively.

CONCLUSION

Fortunately, almost all cases with COVID-19 vaccination-associated thyroid dysfunctions had a favorable outcome following therapy. The benefits of COVID-19 vaccinations in terms of terminating the pandemic and/or reducing mortality rates can exceed any risk of infrequent complications such as a transient thyroid malfunction.

Ramsar, Iran, as a Natural Radiobiological Surrogate for Mars

ABSTRACT

Terrestrial experiments involving acute exposures of low-LET radiation on inbred lab animals are quick, simple, and inexpensive but are relatively uninformative about the real radiobiological hazards of planned manned space missions. A more predictive model could involve human beings chronically exposed to "space-like" high-LET radiation. Such radiation exposure has been ongoing for thousands of years in Ramsar, Iran, and some other high-LET high background radiation regions on Earth. Examining the health of Ramsar residents can be illuminating and potentially relevant to space missions.

Space Medicine: Why Do Recently Published Papers about Telomere Length Alterations Increase our Uncertainty Rather than Reduce it?

There is a growing interest in examining alterations in telomere length as a reliable biomarker of general health, as well as a marker for predicting later morbidity and mortality. Substantial evidence shows that telomere length is associated with aging; telomere shortening acts as a "counting mechanism" that drives replicative senescence by limiting the mitotic potential of normal (but not malignant) cells. In this Correspondence, we attempt to answer the question of why recently published papers about telomere length alterations increase our uncertainty rather than reduce it. This discussion includes three major research areas regarding telomere length: environmental stressors, aging, and life span. Our review suggests that activation of telomerase activity due to stressors in space might be a double-edged sword with both favorable and unfavorable consequences. The selection of an effect's consequence must clearly elucidate the experimental conditions as well as associated stressors. In this Correspondence, we attempt to answer the question of why recently published papers about telomere length alterations increase our uncertainty rather than reduce it. The selection of an effect's consequence must clearly elucidate the experimental conditions as well as associated stressors. Both positive and negative consequences must be clearly addressed in order to bolster the conclusions, as well as identify future research directions.

How Our Neanderthal Genes Affect the COVID-19 Mortality: Iran and Mongolia, Two Countries with the Same SARS-CoV-2 Mutation Cluster but Different Mortality Rates

Neanderthal genes possibly gave modern human protection against viruses. However, a recent study revealed that that a long sequence of DNA that is inherited from our Neanderthal ancestors can be linked to severe COVID-19 infection and hospitalization. Substantial evidence now indicates that our genetic background may be involved in the transmissibility of SARS-CoV-2 and the rapid progress of COVID-19 in some infected individuals. Although both morbidity and mortality of COVID-19 strongly depends on key factors such as age and co-existing health conditions, potential classes of human genomic variants possibly affect the likelihood of SARS-CoV-2 infection and its progress. Despite Iran and Mongolia seem to share the same SARS-CoV-2 mutation cluster, the COVID-19 mortality rates in these two countries are drastically different. While the population in Iran is 25.8 times higher than that of Mongolia, the number of confirmed cases is 1170 times higher. Moreover, the death rate shows a drastic difference. Since Neanderthals interbred with modern humans in Middle East between 47,000 and 65,000 years ago before going extinct 40,000 years ago, some Iranians have much more Neanderthal DNA than other people. Although neither genetic background nor environmental factors alone can determine our risk of developing severe COVID-19, our genes clearly affect both the development and progression of infectious diseases including COVID-19. Given these considerations, we believe that these great differences, at least to some extent, can be due to the proportion of Neanderthal genes among the people of these two countries

Combined Effects of Radiofrequency Electromagnetic Fields and X-Ray in Renal Tissue and Function

PURPOSE

Biochemical and histopathological properties of renal tissues were reported to be affected by both radiofrequency electromagnetic fields (RF-EMF) and ionizing radiation. The radiation-induced changes in the kidney, including the serum levels of blood urea nitrogen (BUN) and creatinine (Cr), could lead to adverse health outcomes such as chronic kidney disease. These complications signify the importance of the research in this field. Thus, in this study, the effects of ionizing and non-ionizing radiations, as well as their combination, were assessed by evaluating the alteration in BUN, Cr, and histopathological changes in kidney tissue.

MATERIALS AND METHODS

Ninety-six male Wistar rats were randomly divided into six groups and were exposed to either 900/1800MHz (mobile phone) or 2.4 GHz RF-EMF (Wi-Fi) radiation for 14 days, 8Gy x-ray, or their combination. Sera were collected from 2 mL of rat blood, then BUN and Cr levels were determined. Also, renal samples were stained with hematoxylin and eosin and evaluated histopathologically.

RESULTS

Both BUN and Cr levels raised non-significantly after exposure to 8 Gy x-rays. Moreover, all measurements in the samples of x-ray groups were in borderline or higher than normal values. The BUN levels of control, Wi-Fi, x-ray, and Wi-Fi+x-ray groups were not significantly different. However, Cr levels in the Wi-Fi group were significantly higher than those of the controls, and BUN to Cr ratio levels were significantly lower than those of the controls. Also, tubular atrophy and vessel wall thickening were associated with these exposures.

CONCLUSION

Exposure to 900/1800MHz, 2400 MHz EMF can alter the kidney function. However, pre-exposure to 900/1800MHz EMF could modulate the acute adverse effects of lethal x-ray dose, which addresses the adaptive response in the kidney.

AN ARTIFICIAL NEURAL NETWORK-BASED MODEL FOR PREDICTING ANNUAL DOSE IN HEALTHCARE WORKERS OCCUPATIONALLY EXPOSED TO DIFFERENT LEVELS OF IONIZING RADIATION

We presented an artificial intelligence-based model to predict annual effective dose (AED) value of health workers. Potential factors affecting AED and the results of annual blood tests were collected from 91 radiation workers. Filter-based feature selection strategy revealed that the eight factors plate, red cell distribution width (RDW), educational degree, nonacademic course in radiation protection (hour), working hours per month, department and the number of procedures done per year and work in radiology department or not (0,1) were the most important predictors for AED. The prediction model was developed using a multilayer perceptron neural network and these prediction parameters as inputs. The model provided favorable accuracy in predicting AED value while a regression model did not. There was a strong linear relationship between the predicted AED values and the measured doses (R-value =0.89 for training samples and 0.86 for testing samples). These results are promising and show that artificial neural networks can be used to improve/facilitate dose estimation process.

Assessment of function, histopathological changes, and oxidative stress in liver tissue due to ionizing and non-ionizing radiations

BACKGROUND

Compared to past decades, humans are exposed to rapidly increasing levels of radiofrequency electromagnetic radiations (RF-EMF). Despite numerous studies, the biological effects of human exposure to different levels of RF-EMF are not fully understood yet. This study aimed to evaluate the bioeffects of exposure to "900/1800 MHz" and "2.4 GHz" RF-EMFs, and x-rays alone as well as their potential interactions, i.e. inducing simple additive, adaptive, or synergistic effects.

METHODS

120 Wistar rats were randomly divided into ten groups of 12 each. The rats were exposed to RF-EMF, 10 cGy, and 8 Gy x-rays, a combination of these exposures, or only sham-exposed. The levels of liver enzymes were determined in serum samples by an auto-analyzer. Moreover, the histopathological changes, and the levels of malondialdehyde (MDA), nitric oxide, ferric reducing antioxidant power, total thiols, and protein carbonyl (PCO) were measured.

RESULTS

Among the markers of liver function, gamma-glutamyltransferase was not associated with irradiation but, aspartate transaminase, alanine transaminase, and alkaline phosphatase showed some levels of association. MDA and PCO levels after 8 Gy irradiation increased, but pre-exposure to RF-EMF could modulate their changes. At the cellular level, the frequency of lobular inflammation was associated with the type of intervention.

CONCLUSION

The exposure to both ionizing and non-ionizing radiations could alter some liver function tests. A short term pre-exposure to RF-EMF before exposure to an 8 Gy challenging dose of x-rays caused the alterations in oxidative stress markers and liver function tests, which indicate that oxidative stress is possibly involved in the adaptive response.

Synergistic Effect of Radiofrequency Electromagnetic Fields of Dental Light Cure Devices and Mobile Phones Accelerates the Microleakage of Amalgam Restorations: An in vitro Study

BACKGROUND

Previous studies have shown that exposure to electromagnetic fields produced by magnetic resonance imaging or mobile phones can lead to increased microleakage of dental amalgam.

OBJECTIVE

The aim of the present study was to investigate the effect of electromagnetic field of a commercial dental light cure device and a common GSM mobile phone on microleakage of amalgam restorations.

MATERIALS AND METHODS

Identical class V cavities were prepared on the buccal surfaces of 60 non-carious extracted human teeth. The samples were randomly divided into 4 groups of 20 samples each. The samples in the first group were not exposed to electromagnetic fields, while the second and the third groups were exposed to electromagnetic fields produced by a commercial light cure device, or mobile phone radiation (60 min), respectively. The fourth group was exposed to electromagnetic radiations emitted by both mobile phone for 60 min and light cure device. Then, teeth samples were scored for microleakage according to a standard dye penetration protocol by examination under a stereomicroscope.

RESULTS

The mean score of microleakage in the fourth group (light cure + mobile phone) was significantly higher than that of the control group (P =0.030). Moreover, the scores of microleakage in this group were significantly higher than that of the second group (light cure only) (P= 0.043).

CONCLUSION

Exposure of amalgam restorations to electromagnetic fields produced by both light cure devices and mobile phones can synergistically increase the microleakage of amalgam restorations.

Blocking Short-Wavelength Component of the Visible Light Emitted by Smartphones' Screens Improves Human Sleep Quality

BACKGROUND

It has been shown that short-wavelength blue component of the visible light spectrum can alter the circadian rhythm and suppress the level of melatonin hormone. The short-wavelength light emitted by smartphones' screens can affect the sleep quality of the people who use these devices at night through suppression of melatonin.

OBJECTIVES

In this study, we examined the effects of covering the screens of smartphones with different filters (changing the effective wavelength of the light) on sleep delay time in 43 healthy students.

MATERIALS AND METHODS

Volunteer students were asked to go to bed at 23:00 and to use their mobile phones in bed for watching a natural life documentary movie for 60 minutes. No filter was used for one night while amber and blue filters were used for other 2 nights. Photospectrometry method was used to determine the output spectrum of the light passing through the filters used for covering the screens of the mobile phones. The order for utilizing amber or blue filters or using no filter was selected randomly. After 1 hour, the participants were asked to record their sleep delay time measured by a modified form of sleep time record sheet.

RESULTS

The mean sleep delay time for the "no-filter" night was 20.84±9.15 minutes, while the sleep delay times for the nights with amber and blue filters were 15.26±1.04 and 26.33±1.59 minutes, respectively.

CONCLUSION

The findings obtained in this study support this hypothesis that blue light possibly suppresses the secretion of melatonin more than the longer wavelengths of the visible light spectrum. Using amber filter in this study significantly improved the sleep quality. Altogether, these findings lead us to this conclusion that blocking the short-wavelength component of the light emitted by smartphones' screens improves human sleep.

Comments regarding: "Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach"

This commentary addresses the paper by Vila et al. entitled "Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach" that is published in Environment International. The authors have examined the link between occupational exposures to radiofrequency (RF) and intermediate frequency (IF) electromagnetic fields (EMF) and glioma and meningioma brain tumor risk in the INTEROCC multinational population-based case-control study. This study showed no clear association with exposure to RF or IF EMFs and the risk of glioma or meningioma brain tumors. Recent studies show that in many cases there are large errors and/or major shortcomings in the studies claiming no link between mobile phone and brain cancer. Although the paper by Vila et al. is well-structured and can be considered as a significant contribution to this field, there are several items that merit further attention and are not fully addressed. These include the selection bias, confounding factors other than age, sex, region and country, and criteria used in this study for considering exposures as occupational.

Exposure to indoor radon can be a concern in studies on the role of short-term exposure to air pollution and mortality

Recent studies show that short-term exposure to ambient particulate matter is associated with more emergency department visits and hospitalizations for pneumonia as well as increased mortality and increased health care costs among older adults. Moreover, exposure to ambient particulate matter is shown to be connected with an increased rate of daily mortality and hospitalizations due to cardiovascular diseases (CVDs). The association between short-term exposures to particulate matter with a diameter less than 2.5 µm (PM2.5) and ozone [at levels below the current daily National Ambient Air Quality Standards (NAAQS)] and mortality in the continental United States has been recently addressed by some researchers. Although exposure to radon is usually known to cause late health effects such as lung cancer, some studies show a significant association between radon exposure and cerebrovascular disease (CeVD) mortality. In some residential areas with high levels of radon, it has been found that the incidences of respiratory, nervous system and cardiovascular system diseases exceed the average. Studies that calculated the radiation dose to blood and the walls of coronary arteries from radon and progeny also indicate that exposure to radon can increase the incidence of CVDs. Based on the evidence provided in this short communication, it can be concluded that ignoring the key role of radon in non-cancer mortality can easily affect the validity of the studies aimed at investigating the association between exposure to ambient fine particulate matter and mortality.

Does Exposure to Static Magnetic Fields Generated by Magnetic Resonance Imaging Scanners Raise Safety Problems for Personnel?

MRI workers are occupationally exposed to static and time-varying gradient magnetic fields. While the 24-hour time-averaged exposure to static magnetic fields is about a few mT, the maximum static field strength can be as high as 500 mT during patient setup. Over the past several years, our laboratory has performed extensive experiments on the health effects of exposure of animal models and humans to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. This study is to investigate the adverse health effects in MRI workers and also to assess the effect of exposure of MRI workers to static magnetic fields on their cognitive functions. In the first phase of this study a questionnaire was designed to collect information from 120 MRI personnel. The collection of data about the adverse health effects was based on self-reporting by the participants. In the second phase, 47 volunteer university students were asked to continuously move around a 1.5 T MRI scanner. Visual reaction time and working memory tests were performed on all participants before and after the experiment. Forward digit span and backward digit span were used for assessing the working memory. Furthermore, participants were asked to report the symptoms they had experienced during the movement. The first phase of our study showed increased frequencies of adverse health effects in MRI workers. In this study the rates of self-reported symptoms such as a headache, sleep problems, myalgia, palpitation, fatigue, concentration problems, attention problems, nervousness and backpain were possibly affected by static magnetic field. Furthermore we found that reaction time and working memory could be influenced by the movements of the body around a MRI scanner. It can be concluded that movement through a high magnetic field can also lead to some adverse cognitive effects in MRI staff.

Commentary regarding: "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1"

Deep space missions, including Mars voyages, are an important area of research. Protection of astronauts' health during these long-term missions is of paramount importance. The paper authored by Szarka et al. entitled "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1" is indeed a step forward in this effort. Despite numerous strengths, there are some shortcomings in this paper including an incomplete description of the space radiation environment as well as discussion of the resulting biological effects. Due to complexity of the space radiation environment, a careful analysis is needed to fully evaluate the spectrum of particles associated with solar particle events and galactic cosmic radiation. The radiation source used in this experiment does not reproduce the range of primary galactic cosmic radiation and solar particle events particles and their associated energies. Furthermore, the effect of radiation interactions within the spacecraft shell and the potential effects of microgravity are not considered. Moreover, the importance of radioadaptation in deep space missions that is confirmed in a NASA report is neither considered. Other shortcomings are also discussed in this commentary. Considering these shortcomings, it can be argued that Szarka et al. draw conclusions based on an incomplete description of the space radiation environment that could affect the applicability of this study.

Alzheimer 's Disease: Possible Mechanisms Behind Neurohormesis Induced by Exposure to Low Doses of Ionizing Radiation

In 2016, scientists reported that human exposure to low doses of ionizing radiation (CT scans of the brain) might relieve symptoms of both Alzheimer's disease (AD) and Parkinson disease (PD). The findings were unbelievable for those who were not familiar with neurohormesis. X-ray stimulation of the patient's adaptive protection systems against neurodegenerative diseases was the mechanism proposed by those authors. Now, some more recent studies performed in the field of neurobiological research confirm that low levels of stress can produce protective responses against the pathogenic processes. This paper outlines possible protective consequences of LDR in preventing the pathogenesis of AD through mechanisms such as restoring the myelin sheath and preventing neurodegeneration caused by oxidative stress. Focal demyelination is frequently reported in the proximity of beta-amyloid plaques within neocortex. Extracellular accumulation of amyloid is among well-characterized pathological changes in AD. It should be noted that LDR has been shown to contribute to the regeneration and functional recovery after transverse peripheral nerve injury (through inducing increased production of VEGF and GAP-43), which advances both the axonal regeneration and myelination. Another mechanism which is possibly involved is preventing neurodegeneration caused by oxidative stress. While high doses can induce reactive oxygen species (ROS) formation, oxidative stress and neuro-inflammation, substantial evidence now indicates that LDR can mitigate tissue damage through antioxidant defenses. Although adult neurogenesis has been reported to be beneficial for the regeneration of nervous system, some studies demonstrate that neurogenesis increases in AD brains. In spite of these reports, cellular therapy is introduced as a promising strategy for AD, and hence, LDR can affect the proliferation and differentiation of neural stem cells. Although such mechanisms are not fully known yet, it is hoped that this paper would foster further investigation into the mechanisms of this phenomenon, which accordingly improves human health.

Cancers of the Brain and CNS: Global Patterns and Trends in Incidence

Miranda-Filho et al. in their recently published paper entitled "Cancers of the brain and CNS: global patterns and trends in incidence" provided a global status report of the geographic and temporal variations in the incidence of brain and CNS cancers in different countries across continents worldwide. While the authors confirm the role of genetic risk factors and ionizing radiation exposures, they claimed that no firm conclusion could be drawn about the role of exposure to non-ionizing radiation. The paper authored by Miranda-Filho et al. not only addresses a challenging issue, it can be considered as a good contribution in the field of brain and CNS cancers. However, our correspondence addresses a basic shortcoming of this paper about the role of electromagnetic fields and cancers and provides evidence showing that exposure to radiofrequency electromagnetic fields (RF-EMFs), at least at high levels and long durations, can increases the risk of cancer.

Comments on "Radiofrequency electromagnetic fields and some cancers of unknown etiology: An ecological study"

This correspondence refers to the Science of the Total Environment article by Gonzalez-Rubio et al. entitled "Radiofrequency electromagnetic fields and some cancers of unknown etiology: An ecological study". Authors of this paper have presented the findings of their preliminary epidemiological study which combined epidemiology, statistics and geographical information systems (GIS). Gonzalez-Rubio et al. have analyzed the possible link between exposure to Radiofrequency Electromagnetic Fields (RF-EMF) in the city of Albacete, Spain and the incidence of cancers such as lymphomas, and brain tumors. The shortcomings of this study are discussed.

Comments on "Incidence of cancer among licensed commercial pilots flying North Atlantic routes"

Gudmundsdottir et al. in their paper entitled "Incidence of cancer among licensed commercial pilots flying North Atlantic routes" published in Environmental Health have evaluated the effects of exposure to higher levels of cosmic radiation on cancer incidence in the pilots of commercial flights. Despite its remarkable strengths, the paper authored by Gudmundsdottir et al. has some shortcomings. The shortcomings of this paper such as not determining the shape of dose-response relationship for radiation-induced cancers, limitations in flight dose calculations, the weaknesses of CARI-6 as the program used by Gudmundsdottir et al. to estimate the effective dose of galactic cosmic rays, and the problems associated with unpredictable nature of the magnitude and duration of solar particle events are discussed.

Comments on "Association of excessive mobile phone use during pregnancy with birth weight: an adjunct study in Kumamoto of Japan Environment and Children's Study"

We have read with interest the article by Lu et al. entitled “Association of excessive mobile phone use during pregnancy with birth weight: an adjunct study in Kumamoto of Japan Environment and Children’s Study” published recently in the Environmental Health and Preventive Medicine. Although this paper addresses a very challenging issue, it has some shortcomings. Mortazavi et al. have previously studied the effects of ionizing and non-ionizing radiation on birth weight of newborns and found no statistical significant differences between the mean weight of newborns whose mothers had been exposed to electromagnetic fields (EMF) generated by mobile phones and those of non-exposed mothers. The study performed by Lu et al. cannot answer this very key question that whether ordinary use of mobile phone during pregnancy can lead to low birth weight. The origin of the controversy between the findings of these two studies and the shortcomings of the article by Lu et al. are discussed.

Evaluation of Radiation Exposure Pattern and Radiation Absorbed Dose Resulting from Occupational Exposure of Anesthesiologists to Ionizing Radiation

INTRODUCTION

Little information is available concerning the radiation exposure of anesthesiologists, and no such data have previously been collected in Iran. This prospective study was performed to determine the amount of radiation exposure of anesthesiologists for the purpose of assessing whether or not dangerous levels of radiation exposures were being reached, and to identify factors that correlate with excessive risk.

PARTICIPANTS AND METHODS

The radiation exposure of all anesthesiology residents and the attending of Shiraz University of Medical Sciences during a 3-month period (from June to August 2016) was measured using a film badge with monthly readings. Physicians were divided into two groups: group 1 (the ones assigned to ORs with radiation exposure), and group 2 (the ones assigned to ORs with no or minimal radiation exposure).

RESULTS

A total number of 10744 procedures were performed in 3 major university hospitals including 353 cases of pediatric angiography, 251 cases of percutaneous nephrolithotomy, 43 cases of chronic pain palliation and 672 cases of orthopedic surgeries with C-arm application. In all 3 months, there were statistically significant differences in the amount of radiation exposure between the two groups.

CONCLUSION

Anesthesiologists working in the cardiac catheterization laboratory, pain treatment service, orthopedic and urologic ORs are exposed to statistically significantly higher radiation levels compared to their colleagues in other ORs. The radiation exposure to anesthesiologists can rise to high levels; therefore, they should get proper teaching, shielding and periodic evaluations.