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The sensitivity to ionizing radiation is increasing by age of development for some malignant tumors. Therefore, children have higher risk to radiation induced tumors due the high cellular rate of proliferation and long lifespan probability. The risk is also increase with increase the effective and organ doses. Computed tomography (CT) exposed pediatric patients to higher radiation dose during multiphase image acquisition, repeated exams, for follow-up procedures. This research intended to estimate the radiogenic risks and effective radiation doses resulted from CT enhanced contrast for abdomen and pelvis. 126 (66 (62.3%) males, 60 (47.7%) females) pediatric patients underwent CT enhanced abdominal examination at Medical Imaging Department at King Khalid Hospital and Prince Sultan Center for Health Services, Alkharj, Saudi Arabia. The average and range of pediatric age (years) is 11.6 ± 5.0 (0.1-17). The mean, standard deviation, and range of the volume CT air kerma index (C VOL (mGy) and the air kerma length product (P KL , mGy.cm) were 9.8 ± 9.4 (2.1-45.8) and 1795 (221-3150) per abdominopelvic procedure, respectively. The mean and range of the effective dose (mSv) per procedure are 26.9 (2.4-59.1). The effective dose is higher compared to the most previously published studies. The effective dose per pediatric abdomen and pelvis with contrast procedure suggest that the patient dose is not optimized yet. Because the chest and pelvis region contain sensitive organs that are irradiated repeatedly, dose optimization is crucial., Competing Interests: Declaration of competing interest All authors declare that there is no conflict of Interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Due to the extended localized fluoroscopy, many radiographic exposures, and multiple procedures that might result in tissue reaction, patients and personnel received a significant radiation dose during interventional cardiology (IR) procedures. This study aims to calculate the radiation risk and assess patient and staff effective doses during IC procedures. Thirty-two patients underwent a Cath lab treatment in total. Ten Cath lab personnel, including six nurses, two cardiologists, and two X-ray technologists. Optical stimulating-luminescent dosimeters (OSL) (Al2O3:C) calibrated for this purpose were used to monitor both occupational and ambient doses. Using an automated OSL reader, these badges were scanned. The Air Kerma (mGy) and Kerma Area Products (KAP, mGy.cm 2 ) have a mean and standard deviation (SD) of 371 ± 132 and 26052, respectively. The average personal dose equivalent (mSv) and its range for cardiologists, nurses and X ray technologists were 1.11 ± 0.21 (0.96-1.26), 0.84 ± 0.11 (0.68-1.16), and 0.68 ± 0.014 (0.12-0.13), respectively. The current study findings showed that the annual effective dose for cardiologists, nurses, and X-ray technologists was lesser than the yearly occupational dose limit of 20 mSv recommended by national and international guidelines. The patients' doses are comparable with some previously published studies and below the tissue reaction limits., Competing Interests: Declaration of competing interest All authors declare that there is no conflict of Interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Occupational radiation exposure can occur due to various human activities, including the use of radiation in medicine. Occupationally exposed personnel surpassing 7.4 millions, and respresent the biggest single group of employees who are exposed to artificial radiation sources at work. This study compares the occupational radiation dose levels for 145 workers in four different hospitals located in the Aseer region in Saudi Arabia. The occupational exposure was quantified using thermoluminescence dosimeters (TLD-100). The levels of annual occupational exposures in targeted hospitals were calculated and compared with the levels of the international atomic energy agency (IAEA) Safety Standards. An average yearly cumulative dose for the two consecutive years. The average, highest and lowest resulted occupational doses under examination in this work is 1.42, 3.9 mSv and 0.72 for workers in various diagnostic radiology procedures. The resulted annual effective dose were within the IAEA approved yearly dose limit for occupational exposure of workers over 18, which is 20 mSv. Staff should be monitored on a regular basis, according to current practice, because their annual exposure may surpass 15% of the annual effective doses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Breast cancer is a common malignancy for females (25% of female cancers) and also has low incidence in males. It was estimated that 1% of all breast malignancies occur in males with mortality rate about 20%, with annual increase in incidence. Risk factors include age, family history, exposure to ionizing radiation and high estrogen and low of androgens hormones level. Diagnosis and screening are challenging due to limiting effectiveness of breast cancer screening. Therefore, patients may expose to ionizing radiation that may contribute in breast cancer incidence in males. In literature, limited studies were published regarding radiation exposure for males during mammography. The objective of this research is to quantify patient doses during male mammogram and to estimate the projected radiogenic risk during the procedure. In total, 42 male patients were undergone mammogram for breast cancer diagnosis during two consecutive years. The mean and range of patient age (years) is 45 (23-80). The mean and standard deviation (SD) of the peak tube potential and tube current time product are 28.64 ± 2. and 149 ± 35.1, respectively. The mean, and range of patients' entrance surface air kerma (ESAK, mGy) per single breast procedure was 5.3 (0.47-27.5). Male patient's received comparable radiation dose per mammogram compared to female procedures. With increasing incidence of male breast cancer, proper guidelines are necessary for the mammographic procedure are necessary to reduce unnecessary radiation doses and radiogenic risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

CT scanning deliver much higher radiation doses than planar radiological procedures, which puts patients to high risks. This study measures and evaluates patient doses during chest and abdomen computed tomography procedures. Particular attention is given to measuring the dose to the equivalent breast (mSv) and to estimate the associated risks of breast cancer to young female patients (15-35 years). Data was obtained from standard examinations from three hospitals. The measured values of CT dose indexes, CTDI (mGy) as well as exposure-related parameters were used for assessment. Breast and effective doses were extrapolated using a software. The results showed remarkable variations of the mean organ equivalent doses for similar CT examinations in the studied hospitals. This could be attributed to the variation in CT scanning imaging technique, and clinical indications. The average effective dose to the chest was 7.9 mSv (2.3-47.0 mSv) and for the abdomen the mean dose was 6.6 mSv, ranging from (3.3-27 mSv). The breast received equivalent doses from chest and abdomen procedures as follows: 10.2 (1.6-33 mSv) and 10.1(2.3-19 mS) Sv respectively. Each procedure yielded high risks of breast cancer for young females. Implementation of accurate referral criteria is recommended to avoid unnecessary breast radiation exposure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Staff occupational radiation exposure is limited to 20 mSv annually to preclude tissue reaction and lower risk of cancer effect. Staff occupational exposure arises during the preparation, injection, and scanning of the patients. Recent studies reported that nuclear medicine personnel might exceed the annual dose limit in high workload and poor radiation protection circumstances. Therefore, an accurate estimation of the annual dose limit is recommended. The goal of this research is to calculate the cumulative external effective dose (mSv) per year for nuclear medicine physicians, technologists, and nurses at SPECT/CT department. A total of 15 staff worked in the nuclear medicine department at King Saud Medical City (KSMC), Riyadh, Saudi Arabia were evaluated for the last six years. 99m Tc is used more frequently for most of the patients. The procedures include renal, cardiac scintigraphy procedures. Staff dose was quantified using calibrated thermoluminecnt dosimeters (TLD-100) with an automatic TLD reader (Harshaw 6600). Exposure to ionizing radiation was evaluated in terms of deep doses (Hp(10) were evaluated. The overall average and standard deviation of the external doses for nuclear medicine physicians, technologists' and nurses were 1.8 ± 0.7, 1.9 ± 0.6, 2.0 ± 0.9, 2.2 ± 0.8, 6.0 ± 2.8, and 3.6 ± 1.3 for the years 2015,2016,2017,2018,2019, and 2020, respectively. Technologists and nurses received higher doses of compared to the nuclear medicine physicians. Technologists and nurses involved in radionuclide preparation, patients' injection, and image acquisition. Staff annual exposure is below the annual dose limits; however, this external dose is considered high compared to the current workload., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The positron emitters ( 18 F-Sodium Fluoride (NaF)) and X-rays used in Positron emission tomography (PET) combined with computed tomography (PET/CT) imaging have a high radiation dose, which results in a high patient dose. The present research intends to determine the radiation dose and risks associated with PET/CT- 18F-Sodium fluoride examinations in patients. The 18F-NaF PET/CT was used to investigate the doses of 86 patients. Patient exposure parameters and ImPACT software were used to calculate mean effective doses. The administered activity of 185 MBq (5.0 mCi) per procedure has a mean and range based on the patient's BMI (BMI). The range of patient effective doses per procedure was found to be 4-10 mSv, with a radiation risk of 1 × 10 -5 per procedure. Patient doses are determined by the patient's size, scanner type, imaging protocol, and reconstruction method. For further dose reduction, proper justification and radiation dose optimization is required., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Ionizing radiation exposure from medical applications is increasing annually worldwide. It was estimated that 325 million dental procedures were performed in the United States. Radiation exposure from dental radiography consists of intraoral, panoramic, and 3D imaging cone-beam computed tomography (CBCT) imaging. Recent studies reported an association between dental imaging procedures and increased cancer probability of brain and thyroid. Previous studies showed that some dental imaging practices exposed patients and staff to unnecessary radiation doses due to incorrect image acquisition and insufficient radiation protection measures. This study aims to (i) measure the occupational and patients doses during dental procedures and (ii) assess the current imaging techniques and radiation protection practices. Two hundred fourteen patients were evaluated for periapical, bitewing, cephalometric, occlusal, and panoramic procedures. Organ equivalent doses were quantified for the breast, eye lens, and thyroid gland during CBCT procedure. Occupational and ambient dose assessment were assessed using calibrated thermoluminescent dosimeters (TLD-100(LiF: Mg. Ti). Ambient doses were measure at different locations at the department using TLDs. Patients' radiation doses were quantified using kerma area product (PKA (mGy.cm) and the entrance surface air kerma (ESAK (mGy). Fixed tube voltage (65 kVp) and tube current-time product (7 mAs) were used. The overall mean, sd, and range of patients dose values during intraoral (mGy), panoramic and CBCT examinations were 4.6 ± 0.7 (1.4-7.1), 135 ± 45 (75.2-168.5), and 215 ± 165 (186-2115), respectively. The mean and range of the annual occupational doses (mSv) were 1.4 (0.6-3.7), which below the annual dose limits for radiation workers (20 mSv/y). The study showed that inadequate radiation protection for patients existed in terms of the use of the thyroid shield, the technologist's presence inside the room during radiation exposure. Patients' radiation doses were comparable with the international diagnostic reference level (DRL). Staff education and training in radiation protection aspects are highly recommended., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study analysed thermoluminescence (TL) glow curves of the polymer pencil lead graphite (PPLG) due to its potential applications in radiation dosimetry. The TL glow curves provide information on the physical parameters of the defects participating in luminescence process. The glow curves for different diameters PPLG samples were obtained with varying temperature from 50 to 300 °C, at a fixed heating rate of 10 °Cs -1 . A number of methods (initial rise, peak shape and curve fitting) were used to fit the TL glow peaks of the PPLG samples obtained under photon dose of 200 Gy. From the fitted TL signals, the trap parameters such as the order of kinetics, the activation energy, the frequency factor, etc. for the individual peaks were numerically determined. The lifetimes of TL process were calculated assuming the first-order kinetics. The results are compared among the different methods adopted in this study. Implications about the possible results in glow curve deconvolution are discussed., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The main objective of this study is to identify the atmospheric 7 Be concentrations in 130 surface air samples collected from three stations located in Riyadh, Haql and Khafji cities in Saudi Arabia between November 2012 and April 2014. Monthly variations as well as seasonal patterns of 7 Be were studied using a medium-volume air sampler and a gamma spectroscopy system equipped with a high-purity germanium (HPGe) detector. 7 Be exhibited one maximum specific activity in summer and one minimum in winter with average monthly concentrations of 12.4 ± 0.9, 15.4 ± 1.2, and 18.0 ± 1.3 mBq m -3 in Riyadh, Haql and Khafji, respectively. Overall, the average 7 Be concentration in the three stations was 12.9 ± 1.0 mBq m -3 , whereas the maximum value of 29.5 mBq m -3 was registered in Khafji city in August 2013. Besides 7 Be, measurements indicate observations of 4 0  K, 137 Cs, 226 Ra radionuclides in surface air samples collected from the three stations. 4 0  K showed measurable concentrations, whereas the concentrations of 137 Cs and 226 Ra were only detected in a limited number of samples., (Copyright © 2020 Elsevier Ltd. All rights reserved.)