Need For Radiation Protection Research Articles

GEANT4 simulation of X-ray radiation for sterilizer based on high-current repetitively pulsed electron accelerator SINUS-320

Secondary X-ray radiation for the sterilizer based on high-current repetitively pulsed electrons accelerator SINUS-320 has been investigated. The energy of accelerated electrons is 500 keV. In this regard, there is a need for radiation protection during operation of the installation, which, in turn, leads to the importance of studying the dose rate of secondary X-ray radiation. The studies were carried out by statistical modeling using the GEANT4 simulation toolkit.

Updated risk models for lung cancer due to radon exposure in the German Wismut cohort of uranium miners, 1946-2018.

UNSCEAR recently recommended that future research on the lung cancer risk at low radon exposures or exposure rates should focus on more contemporary uranium miners. For this purpose, risk models in the German Wismut cohort of uranium miners were updated extending the follow-up period by 5years to 1946-2018. The full cohort (n = 58,972) and specifically the 1960 + sub-cohort of miners first hired in 1960 or later (n = 26,764) were analyzed. The 1960 + sub-cohort is characterized by low protracted radon exposure of high quality of measurements. Internal Poisson regression was used to estimate the excess relative risk (ERR) for lung cancer per cumulative radon exposure in Working Level Months (WLM). Applying the BEIR VI exposure-age-concentration model, the ERR/100WLM was 2.50 (95% confidence interval (CI) 0.81; 4.18) and 6.92 (95% CI < 0; 16.59) among miners with attained age < 55years, time since exposure 5-14years, and annual exposure rates < 0.5WL in the full (n = 4329 lung cancer deaths) and in the 1960 + sub-cohort (n = 663 lung cancer deaths), respectively. Both ERR/WLM decreased with older attained ages, increasing time since exposure, and higher exposure rates. Findings of the 1960 + sub-cohort are in line with those from large pooled studies, and ERR/WLM are about two times higher than in the full Wismut cohort. Notably, 20-30years after closure of the Wismut mines in 1990, the estimated fraction of lung cancer deaths attributable to occupational radon exposure is still 26% in the full Wismut cohort and 19% in the 1960 + sub-cohort, respectively. This demonstrates the need for radiation protection against radon.

Radiation safety in orthopedic operating theaters: What is the current situation?

ObjectiveTo analyze the exposure of two Orthopedic Surgeons to ionizing radiations in their daily work, and to review the main national and international recommendations on this subject. Material and methodsA retrospective study was conducted on the surgical treatments that use fluoroscopy performed by two orthopedic surgeons during a one year period. An evaluation was made of the radiation received, based on measurements of the processes published in the bibliography section. A literature review of international recommendations and regulations is also presented. ResultsThe radiation received by the two orthopedic surgeons during one year did not exceed the limits of present-day legislation or the new European and international recommendations. The exposure was asymmetrical, with the hands being the most radiated part. The new recommendations reduce the permitted level of radiation on eyes. DiscussionThe evaluation of the radiation received demonstrates the need for radiation protection, paying particular attention to the hands and eyes. Good knowledge of operating a fluoroscope and radiation safety measures are also essential.

Radioprotección en quirófanos de traumatología: ¿en qué situación estamos?

ObjectiveTo analyse the exposure of two Orthopaedic Surgeons to ionizing radiations in their daily work, and to review the main national and international recommendations on this subject. Material and methodsA retrospective study was conducted on the surgical treatments that use fluoroscopy performed by two Orthopaedic Surgeons during a one year period. An evaluation was made of the radiation received, based on measurements of the processes published in the bibliography section. A literature review of international recommendations and regulations is also presented. ResultsThe radiation received by the two Orthopaedic Surgeons during one year did not exceed the limits of present-day legislation or the new European and international recommendations. The exposure was asymmetrical, with the hands being the most radiated part. The new recommendations reduce the permitted level of radiation on eyes. DiscussionThe evaluation of the radiation received demonstrates the need for radiation protection, paying particular attention to the hands and eyes. Good knowledge of operating a fluoroscope and radiation safety measures are also essential.

Image Gently: progress and challenges in CT education and advocacy

Significant progress has been made in radiation protection for children during the last 10 years. This includes increased awareness of the need for radiation protection for pediatric patients with international partnerships through the Alliance for Radiation Safety in Pediatric Imaging. This paper identifies five areas of significant progress in radiation safety for children: the growth of the Alliance; the development of an adult radiation protection campaign Image Wisely™; increased collaboration with government agencies, societies and the vendor community; the development of national guidelines in pediatric nuclear medicine, and the development of a size-based patient dose correction factor by the American Association of Physicists in Medicine, Task Group 204. However, many challenges remain. These include the need for continued education and change of practice at adult-focused hospitals where many pediatric CT exams are performed; the need for increased emphasis on appropriateness of pediatric imaging and outcomes research to validate the performance of CT studies, and the advancement of the work of the first pediatric national dose registry to determine the "state of the practice" with the final goal of establishing ranges of optimal CT technique for specific scan indications when imaging children with CT.

Radiation biology for pediatric radiologists

The biological effects of radiation result primarily from damage to DNA. There are three effects of concern to the radiologist that determine the need for radiation protection and the dose principle of ALARA (As Low As Reasonably Achievable). (1) Heritable effects. These were thought to be most important in the 1950s, but concern has declined in recent years. The current ICRP risk estimate is very small at 0.2%/Sv. (2) Effects on the developing embryo and fetus include weight retardation, congenital anomalies, microcephaly and mental retardation. During the sensitive period of 8 to 15 weeks of gestation, the risk estimate for mental retardation is very high at 40%/Sv, but because it is a deterministic effect, there is likely to be a threshold of about 200 mSv. (3) Carcinogenesis is considered to be the most important consequence of low doses of radiation, with a risk of fatal cancer of about 5%/Sv, and is therefore of most concern in radiology. Our knowledge of radiation carcinogenesis comes principally from the 60-year study of the A-bomb survivors. The use of radiation for diagnostic purposes has increased dramatically in recent years. The annual collective population dose has increased by 750% since 1980 to 930,000 person Sv. One of the principal reasons is the burgeoning use of CT scans. In 2006, more than 60 million CT scans were performed in the U.S., with about 6 million of them in children. As a rule of thumb, an abdominal CT scan in a 1-year-old child results in a life-time mortality risk of about one in a thousand. While the risk to the individual is small and acceptable when the scan is clinically justified, even a small risk when multiplied by an increasingly large number is likely to produce a significant public health concern. It is for this reason that every effort should be made to reduce the doses associated with procedures such as CT scans, particularly in children, in the spirit of ALARA.

SRP Meeting: Social and Political Implications of CommunicatingRadiation Risk Daresbury, Warrington, 20 June 2001

The SRP held a very interesting meeting in June at the Daresbury Laboratory in Warrington on the social and political implications of communicating radiation risk. In today's risk-aware society, effective communication is just as important as the control measures introduced to prevent or restrict exposure.

Patient dose related to the complexity of interventional cardiology procedures.

In interventional cardiology (IC) the PTCA (percutaneous transluminal coronary angioplasty) procedure is the most frequent procedure with the highest dose to the patient. The procedure is usually performed by cardiologists having, in general, insufficient knowledge of radiation physics, radiation technology and radiation protection. The need for radiation protection is of paramount importance in this field of interventional radiology. Correlation between the complexity of PTCA procedure and irradiation parameters (fluoroscopy time, number of images and dose-area product--DAP) has been demonstrated. The presence of severe tortuosity and occlusion of > or = 3 months play a major role. Fluoroscopy time is better correlated with technical factors than DAP, which also includes the influence of patient size, collimation, operation modes, and X ray beam orientation. The number of acquired images is less correlated with the complexity of the PTCA procedure. A complexity index was conceived and procedures were divided into three groups, defined as: simple, medium and complex, which were significantly different in terms of patient dose.

MRI and ultrasound in children with juvenile chronic arthritis

In this era of advancing imaging technology, a knowledge of the relative values of available imaging techniques is necessary to optimize the management of children with juvenile chronic arthritis (JCA). After clinical examination, plain films remain the initial investigation. The need for radiation protection must be a priority in children with JCA. Conventional radiographs allow grouping of the various arthritides (on the base of the distribution and pattern of joint space changes) and staging of disease progression. Ultrasound (US) is very sensitive in the detection of joint effusions, especially in the hip, and guides fluid aspiration. US and Doppler can be used for the evaluation of synovial hypertrophy and activity. Arthrography and to a certain extent nuclear studies have been replaced by magnetic resonance imaging (MRI). MRI can demonstrate articular cartilage, joint effusion, synovial hypertrophy, cortical and medullary bone, cartilage and bone perfusion, and fibrocartilaginous structures (menisci and ligaments). Contrast enhanced MRI is the most sensitive modality to determine whether an arthritic condition is present. However, it does not assist in establishing a specific diagnosis. MRI determines accurately the activity and the extent of the disease and is particularly useful in the early detection of articular damage. Finally, MRI is of major importance in the evaluation of response to local therapy (especially steroids) and the detection of complications.

Radiation protection and quality assurance in diagnostic radiology – an IAEA coordinated research project in Asia and Eastern Europe

The International Atomic Energy Agency currently has two parallel Coordinated Research Projects (CRP) running in Asia and Eastern Europe. The main objective of the CRPs is to raise the level of awareness in participating countries about the need for radiation protection for patients undergoing diagnostic radiology procedures. This is to be achieved by first assessing the status quo in a sample of hospitals and X-ray rooms in each participating country. A program of optimization of radiation protection for patients is then introduced by means of a comprehensive quality assurance program and the implementation of appropriate dose reduction methods, taking into account clinical requirements for diagnostically acceptable images. Patient dose assessment and image quality assessment are to be performed both before and after the introduction of the quality assurance program. The CRP is divided into two phases — the first is concerned with conventional radiography, while the second involves fluoroscopy and computed tomography. The CRP is still running, restricting the scope of this paper to a discussion of the approach being taken with the project. The project will be completed in 1998, with analysis to follow.

Cellular human and viral DNA detection by nonisotopic in situ hybridization.

Abstract In situ hybridization may be defined as the detection of nucleic acids in situ in cells, tissues, chromosomes, and isolated cell organelles. The technique was described in 1969 by two separate groups who demonstrated repetitive ribosomal sequences in nuclei of Xenopus oocytes using radiolabeled probes (1,2). Refinements in recombinant DNA technology and the development of nonisotopic probe labeling and detection (3) obviate the need for radiation protection and disposal facilities, and have converted nonisotopic in situ hybridization (NISH) from a purely research technique to one that can be used in routine laboratory testing.KeywordsCaSki CellReporter MoleculeCervical SmearGlycerol JellyFume CupboardThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Mutagenic effects of a single and an exact number of alpha particles in mammalian cells.

One of the main uncertainties in risk estimation for environmental radon exposure using lung cancer data from underground miners is the extrapolation from high- to low-dose exposure where multiple traversal is extremely rare. The biological effects of a single alpha particle are currently unknown. Using the recently available microbeam source at the Radiological Research Accelerator Facility at Columbia University, we examined the frequencies and molecular spectrum of S1- mutants induced in human-hamster hybrid (A(L)) cells by either a single or an exact number of alpha particles. Exponentially growing cells were stained briefly with a nontoxic concentration of Hoechst dye for image analysis, and the location of individual cells was computer-monitored. The nucleus of each cell was irradiated with either 1,2,4, or 8 alpha particles at a linear energy transfer of 90 keV/microm consistent with the energy spectrum of domestic radon exposure. Although single-particle traversal was only slightly cytotoxic to A(L) cells (survival fraction approximately 0.82), it was highly mutagenic, and the induced mutant fraction averaged 110 mutants per 10(5) survivors. In addition, both toxicity and mutant induction were dose-dependent. Multiplex PCR analysis of mutant DNA showed that the proportion of mutants with multilocus deletions increased with the number of particle traversals. These data provide direct evidence that a single a particle traversing a nucleus will have a high probability of resulting in a mutation and highlight the need for radiation protection at low doses.