Radioprotection issues in uraniferous minerals collections with reference to an actual case.

Our work investigated the radioprotection implications associated with the possession of a collection of uraniferous minerals. Considering different scenarios, we developed (and applied to an actual collection) specific formulas for radiation doses evaluation. We discussed the shielding necessary to reduce the gamma irradiation down to the required values. A mathematical model was developed to estimate the minimum air flow rate to reduce the radon air concentration below the reference values. The radiation risks associated to the handling of single specimens was also addressed, including hand skin irradiation and shielding capabilities of surgical lead gloves. Finally, we discussed the radiation risks associated to the exhibition of a single specimen. The results, compared to the safety standards of the EU Directive 13/59, show that the exhibition of uraniferous samples with activity of a few MBq do not need specific radioprotection requirements nor for the involved personnel nor for visitors.

Copaifera langsdorffii Desf. bark extract: optimisation of dyeing conditions to wool and colour fastness properties.

The ability to add value to waste materials from industrial operations has come to the attention of the wood processing industry, with reports, for example, of extracts from the bark tree conveying colour and UV protection to textile fibres. The objective of the present work was to expand our developments in this arena by using Copaifera langsdorffii Desf. bark extract as a natural dye for textile dyeing. A complete 2³-statistical experimental design and the central point was elaborated. The results showed that the optimal dyeing conditions were 98 °C, for 60 min, using undiluted bark extract. The dyed fabric was analysed by a spectrophotometer using the CIELAB system for evaluation of the colour strength. The results showed a K/S value of 5.78, and the dyed fabric had good colour fastness to rubbing and washing.

Olympic Dam: BHP thinking big about the future.

Olympic Dam is one of the world's most significant polymetallic orebodies producing copper, uranium, gold, and silver in remote South Australia. The polymetallic deposit is located 520 km north-northwest of Adelaide, South Australia and has an inferred resource of 2660 Mt at 1.2% Cu, 1.4 kg t-1 U3Os, and 0.5 g t-1 Au. Ore is mined from the underground operation at a rate of approximately 10 mt year-1, and is processed on site through a concentrator and hydrometallurgical facility, smelter, and electrolytic refinery. Olympic Dam is one of the only sites in the world to claim the 'mine to market' title. Protection of the workforce and the environment has been a primary focus for the operations through its 30+ year life and will continue to be into the future. Broken Hill Propriety Company (BHP) believes that its most important asset is its people. With such a large orebody and a very long potential mine life, it is important to think strategically about the future to ensure the viability of the operation. This requires development of mine and surface processing facilities in a staged manner. Importantly, it also involves the development of people. This presentation provides an overview of BHP's work at Olympic Dam and outlines development plans for Olympic Dam into the future.© 2020 ICRP. Published by SAGE.

Use of Routine Environmental Monitoring Data to Establish a Dose-based Compliance System for a Low-level Radioactive Waste Disposal Site.

A dose-based compliance methodology was developed for Waste Control Specialists, LLC, low-level radioactive waste facility in Andrews, Texas, that allows routine environmental measurement data to be evaluated not only at the end of a year to determine regulatory compliance, but also throughout the year as new data become available, providing a continuous assessment of the facility. The first step in the methodology is a screening step to determine the potential presence of site emissions in the environment, and screening levels are established for each environmental media sampled. The screening accounts for spatial variations observed in background for soil and temporal fluctuations observed in background for air. For groundwater, the natural activity concentrations in groundwater wells at the facility are highly variable, and therefore the methodology uses ratios for screening levels. The methodology compares the ratio of gross alpha to U + U to identify potentially abnormal alpha activity and the ratio of U to U to identify the potential presence of depleted uranium. Compliance evaluation is conducted for any samples that fail the screening step. Compliance evaluation uses the radionuclide-specific measurements to first determine (1) if the dose exceeds the background dose and if so, (2) the dose consequences, so that the appropriate investigation or action occurs. The compliance evaluation is applied to all environmental samples throughout the year and on an annual basis to determine regulatory compliance. The methodology is implemented in a cloud-based software application that is also made accessible to the regulator. The benefits of the methodology over the existing system are presented.

Diagnostic Reference Levels for conventional radiography and fluoroscopy in Austria: Results and updated National Diagnostic Reference Levels derived from a nationwide survey.

OBJECTIVE: Evaluation and updating of Austrian National Diagnostic Reference Levels (NDRLs). METHODS: A nationwide survey on common conventional radiography and fluoroscopy examinations was conducted. In line with Austrian radiation protection standards, all relevant Austrian hospitals and radiology offices/centers were asked to report a minimum sample of 10 representative dose-area product (DAP) values together with patient weight and fluoroscopy time, if applicable. Examinations included for conventional radiography were skull, chest, abdomen, pelvis, lumbar spine and bedside chest x-ray, for fluoroscopy barium enema (single and double contrast) and swallowing (video). Participants were invited via e-mail, followed up by reminders to increase participation rates. Plausibility checks were performed to increase data quality. 3rd quartiles of facility median and mean DAP were calculated and compared to Austrian and international NDRLs. RESULTS: 59% of invited facilities submitted DAP data, 43% submitted additional data on patient weight and 41% on fluoroscopy time. DAP case numbers varied from 1005 to 2121 for conventional radiography and from 182 to 1380 for fluoroscopy. Average patient weight was 75 kg for conventional radiography and 77 kg for fluoroscopy. CONCLUSION: 3rd quartiles derived from the survey are substantially lower than the old Austrian NDRLs (valid till early 2018). Since 3rd quartiles correspond well to European NDRLs, the update would be in accordance with European DRL harmonisation efforts.

Verification of Safety Compliance of Delivering Radionuclides at Vanderbilt University.

Various radionuclides are transported at Vanderbilt University and Vanderbilt University Medical Center on a daily basis, to provide the necessities for diagnostic, therapeutic, and research applications. The delivery of the radionuclides takes various pathways where the general public may receive radiation doses. The Tennessee Department of Environment and Health Radiological Division regulates the dose limits for members of the public to be less than 1 mSv per year and 20 µSv in any hour. We designed a project to verify that potential doses received by the general public meet state regulations. Before the departure of the delivery, dose rates from three directions at a distance of 30 cm with respect to the transport vehicle, were measured using a tissue equivalent survey meter. During the shipment, times were recorded and the number of persons encountered along the path was estimated. Annual and hourly doses were calculated, conservatively assuming that a member of general public would follow the shipment at a distance of 30 cm, for the entire duration of the delivery. Calculated dose rates for each delivery and various combinations of radionuclides were found to be below state regulation limits.

Biological Effects From Low Doses and Dose Rates of Ionizing Radiation: Science in the Service of Protecting Humans, a Synopsis.

There is considerable controversy regarding risk of health detriment after low-level exposure to ionizing radiation. This stems in part from a sort of distance between radiation biologists, epidemiologists, and radiation protection professionals, as well as regulatory institutions. Also, there is a lack of overview of the relevant data and their origins regarding health risks at low doses of ionizing radiation. This feeds seriously into a somewhat hazy fear of ionizing radiation that besets large portions of the public. The current synopsis aims at presenting a holistic view in a concise yet comprehensive manner in order to help people understand the full extent of inputs into attempting to relate low-dose radiation exposure to health risk. It emerges again that different approaches must be found for optimal radiation protection replacing the use of the linear no-threshold (LNT) model.

EURADOS-IDEAS GUIDELINES (VERSION 2) FOR THE ESTIMATION OF COMMITTED DOSES FROM INCORPORATION MONITORING DATA.

Dose assessment after intakes of radionuclides requires application of biokinetic and dosimetric models and assumptions about factors influencing the final result. In 2006, a document giving guidance for such assessment was published, commonly referred to as the IDEAS Guidelines. Following its publication, a working group within the European networks CONRAD and EURADOS was established to improve and update the IDEAS Guidelines. This work resulted in Version 2 of the IDEAS Guidelines, which was published in 2013 in the form of a EURADOS report. The general structure of the original document was maintained; however, new procedures were included, e.g. the direct dose assessment method for (3)H or special procedure for wound cases applying the NCRP wound model. In addition, information was updated and expanded, e.g. data on dietary excretion of U, Th, Ra and Po for urine and faeces or typical and achievable values for detection limits for different bioassay measurement techniques.

Using tea as an artificial urine in a Canadian performance testing program for fission/activation products.

In recent years, the National Calibration Reference Centre for Bioassay and In Vivo Monitoring (NCRC) at the Radiation Protection Bureau (RPB), Health Canada, has been conducting investigations with black tea to develop a matrix that can be used to replace urine in each of the following performance testing programs (PTP): (1) tritium, (2) carbon-14, (3) the DUAL (i.e., 3H/14C), and (4) fission/activation products (F/AP). A 1% tea solution with thimerosal, which had worked successfully for tritium, carbon-14, and the DUAL, was selected and tested for the F/AP PTP because of its similarity to urine in color and UV-VIS spectra. However, application of this tea to samples of the F/AP program containing 133Ba, 137Cs, 57Co, and 60Co produced precipitates, which was an unexpected result. Further experiments showed that replacement of thimerosal with an alcohol at about 5% eliminated the precipitation problem. The alcohol can be ethanol, methanol, or isopropanol. In the experiments, the 1% tea, preserved with alcohol, remained clear and stable for at least 100 d. The duration of each PTP for the NCRC is limited to 90 d. Application of the CNSC S-106 regulatory standard to the tea produced acceptable accuracy and precision results. It was concluded that a suitable tea matrix for the F/AP program had been found.

Practical ways to reduce radiation dose for patients and staff during device implantations and electrophysiological procedures.

Despite the advent of non-fluoroscopic technology, fluoroscopy remains the cornerstone of imaging in most interventional electrophysiological procedures, from diagnostic studies over ablation interventions to device implantation. Moreover, many patients receive additional X-ray imaging, such as cardiac computed tomography and others. More and more complex procedures have the risk to increase the radiation exposure, both for the patients and the operators. The professional lifetime attributable excess cancer risk may be around 1 in 100 for the operators, the same as for a patient undergoing repetitive complex procedures. Moreover, recent reports have also hinted at an excess risk of brain tumours among interventional cardiologists. Apart from evaluating the need for and justifying the use of radiation to assist their procedures, physicians have to continuously explore ways to reduce the radiation exposure. After an introduction on how to quantify the radiation exposure and defining its current magnitude in electrophysiology compared with the other sources of radiation, this position paper wants to offer some very practical advice on how to reduce exposure to patients and staff. The text describes how customization of the X-ray system, workflow adaptations, and shielding measures can be implemented in the cath lab. The potential and the pitfalls of different non-fluoroscopic guiding technologies are discussed. Finally, we suggest further improvements that can be implemented by both the physicians and the industry in the future. We are confident that these suggestions are able to reduce patient and operator exposure by more than an order of magnitude, and therefore think that these recommendations are worth reading and implementing by any electrophysiological operator in the field.

Current opinions on medical radiation: a survey of oncologists regarding radiation exposure and dose reduction in oncology patients.

PURPOSE: The aim of this study was to evaluate oncologists' opinions about the use of ionizing radiation in medical imaging of oncology patients. METHODS: An electronic survey was e-mailed to 2,725 oncologists at the top 50 National Cancer Institute-funded cancer centers. The survey focused on opinions on CT dose reduction in oncology patients and current philosophies behind long-term imaging in these patients. RESULTS: The response rate was 15% (415 of 2,725). Eighty-two percent of respondents stated that their patients or families have expressed anxiety regarding radiation dose from medical imaging. Although fewer than half of oncologists (48%) did not know whether CT dose reduction techniques were used at their institutions, only 25% were concerned that small lesions may be missed with low-dose CT techniques. The majority of oncologists (63%) follow National Comprehensive Cancer Network guidelines for imaging follow-up, while the remainder follow other national guidelines such as those of the Children's Oncology Group, the American Society of Clinical Oncology, or clinical trials. Ninety percent of respondents believe that long-term surveillance in oncology patients is warranted, particularly in patients with breast cancer, melanoma, sarcoma, and pediatric malignancies. The majority of oncologists would consider the use of low-dose CT imaging in specific patient populations: (1) children and young women, (2) those with malignancies that do not routinely metastasize to the liver, and (3) patients undergoing surveillance imaging. CONCLUSIONS: Cumulative radiation exposure is a concern for patients and oncologists. Among oncologists, there is support for long-term imaging surveillance despite lack of national guidelines.

Risk of lung cancer from radon exposure: contribution of recently published studies of uranium miners.

The International Commission on Radiological Protection (ICRP) recently estimated the risk of lung cancer associated with radon exposure, and a statement was issued in ICRP Publication 115. This was based on recent epidemiological studies and the results from a joint analysis of cohorts of Czech, French, and German uranium miners, and indicated that the excess relative risk of lung cancer per unit of exposure should be expressed with consideration of chronic exposure over more than 10 years, by modelling time since median exposure, age attained or age at exposure, and taking in account, if possible, interaction between radon and tobacco. The lifetime excess absolute risk (LEAR) calculated from occupational exposure studies is close to 5 × 10(-4) per working level month (WLM) (14 × 10(-5) per hmJ/m(3)). LEAR values estimated using risk models derived from both miners and domestic exposure studies are in good agreement after accounting for factors such as sex, attained age, and exposure scenario. A sensitivity analysis highlighted the high dependence of background mortality rates on LEAR estimates. Using lung cancer rates among Euro-American males instead of the ICRP reference rates (males and females, and Euro-American and Asian populations), the estimated LEAR is close to 7 × 10(-4) per WLM (20 × 10(-5) per hm J/m(3)).

Uranium mining industry views on ICRP statement on radon.

In 2009, the International Commission on Radiological Protection issued a statement on radon which stated that the dose conversion factor for radon progeny would likely double, and the calculation of risk from radon should move to a dosimetric approach, rather than the longstanding epidemiological approach. Through the World Nuclear Association, whose members represent over 90% of the world's uranium production, industry has been examining this issue with a goal of offering expertise and knowledge to assist with the practical implementation of these evolutionary changes to evaluating the risk from radon progeny. Industry supports the continuing use of the most current epidemiological data as a basis for risk calculation, but believes that further examination of these results is needed to better understand the level of conservatism in the potential epidemiological-based risk models. With regard to adoption of the dosimetric approach, industry believes that further work is needed before this is a practical option. In particular, this work should include a clear demonstration of the validation of the dosimetric model which includes how smoking is handled, the establishment of a practical measurement protocol, and the collection of relevant data for modern workplaces. Industry is actively working to address the latter two items.

Evaluation of tea as a matrix in a dual (3H/14C) performance testing program in Canada.

Urine is the most popular matrix used in performance testing programs (PTP) and inter-comparison programs (ICP) for bioassay. Because it comes from humans, there are concerns regarding its biosafety. For large programs, its collection can take several hours or days to complete. In addition, natural urine has an unpleasant smell, which tends to worsen with increasing storage time. In order to solve some of these problems, the Bioassay Section at the Radiation Protection Bureau in Health Canada has been investigating the use of tea in both PTP and ICP exercises. A method based on diluting tea steeps and scanning them in the UV-VIS range of the light spectrum to select appropriate concentrations as simulated urine for the programs has been published. So far, however, only single H and single C in tea have been studied. The results were found to be compatible and very successful under the S-106 standard of the Canadian Nuclear Safety Commission. This report is an extension of similar investigations and shows that tea samples spiked with both H and C (DUAL) are also compatible and produce excellent PTP results.

Preparation and application of steeps of tea as new simulations of urine for the performance testing programme of 14C.

(14)C is one of the radionuclides for which the Canadian Nuclear Safety Commission has developed performance testing programmes (PTPs). During the PTP exercises, clients receive samples of natural urine containing spiked radionuclides, for testing. In these programmes, urine has disadvantages. These include (1) slow collection times from donors, (2) unpleasant smell and (3) potential to transmit diseases. To assist in solving some of these problems, the Canadian National Calibration Reference Centre for Bioassay and In Vivo Monitoring has conducted research with tea solutions, to find simpler, safer and more readily available alternatives to urine. This paper provides a new technique by which steeps of black tea have been successfully prepared for the (14)C PTP. The results of tea solutions compared well with those of urine. It was concluded that tea steeps, of which the spectroscopic and colour quenching properties have been adjusted, do provide appropriate urine simulations, suitable for use in PTPs.

Normas básicas de seguridad durante el manejo de equipos de radiaciones no ionizantes / Safety basic rules when handling non-ionizing radiation equipment

La preocupación creciente de los trabajadores hacia los posibles efectos nocivos de la exposición a campos electromagnéticos, está suponiendo una percepción desproporcionada de los riesgos derivados de la exposición. En la actualidad, no existe evidencia científica sobre dichos efectos nocivos, siendo aconsejable la vigilancia sobre las exposiciones que están fuera de los límites de seguridad. Desde este Servicio de Prevención y en colaboración con el Servicio de Física Médica, hemos elaborado un procedimiento que garantice, mediante criterios preventivos básicos, la seguridad y salud de los trabajadores que manejan equipos emisores de radiaciones no ionizantes, en nuestro hospital y centros de especialidades. Para la elaboración de este procedimiento hemos revisado la literatura científica relativa a los efectos de los campos electromagnéticos sobre la salud, reuniones periódicas de trabajo entre ambos servicios, identificación y ubicación de los equipos de radiaciones no ionizantes, y asesoramiento por expertos en la materia. El procedimiento establece medidas de control para los trabajadores, y medidas de control para los equipos. Con la finalidad de conseguir una buena difusión e implantación de dicho procedimiento, hemos elaborado dípticos y carteles, donde reflejamos las medidas de control para trabajadores y equipos: Onda Corta, Microondas, Magnetoterapia, Resonancia Magnética Nuclear, Láser y Ultravioleta El procedimiento con sus carteles explicativos ha sido distribuido específicamente por servicios, realizando formación e información de los trabajadores que maneja dichos equipos (AU)

Employee increasing concern about possible dangerous effects of the exposure to electromagnetic fields is meaning a distorted perception of the exposure related risks. Currently, there is no scientific evidence of the dangerous effects mentioned although surveillance over the exposures out of the safety limits is recommended. Within this Prevention Department in cooperation with The Medical Physics Department a procedure based on basic preventive criteria has been elaborated to guarantee health and safety of the employees who handle non-ionizing radiation emitting equipment in our hospital and specialized centers. To draw the procedure: scientific literature related to the electromagnetic fields effects over health has been checked, periodical working meetings have been held between both above mentioned departments; non-ionizing radiation equipment have been identified as well as the places they are based or used; and expert people advice has been used. The procedure sets control and follow-up measurements both for people and equipment such as follows: Shortwave, microwave and magnetic therapy, Nuclear magnetic resonance, Laser, Ultraviolet radiation. The procedure and illustrative posters have been deployed to the linked departments, the information and training having been given to the employees who work with kind of equipment (AU)

Iatrogenic effects of photoprotection recommendations on skin cancer development, vitamin D levels, and general health.

Ultraviolet (UV) radiation is an established carcinogen that causes skin cancers and other cutaneous photodamage. Vitamin D is produced in the skin after UV exposure and may also be obtained from dietary and supplemental sources. The effect of recommendations for UV protection, as well as for very large vitamin D supplements, and possible adverse effects of both are explored. Current evidence supports the conclusion that protection from UV radiation reduces the incidence of skin cancers and photodamage, but generally does not compromise vitamin D status or lead to iatrogenic disease. Conversely, risks of maintaining very high vitamin D levels have not been adequately studied. Vitamin D obtained from diet and supplements is functionally identical to that produced after UV exposure, and is a more reliable and quantifiable source of the vitamin.