PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “RADIATION PROTECTION”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMedDate not supplied

Radiation protection: the NCRP guidelines and some considerations for the future.

The National Council on Radiation Protection and Measurements (NCRP) in the USA and the International Commission on Radiological Protection (ICRP), worldwide, were formed about 1928 and have since made recommendations on appropriate levels of protection from ionizing radiation for workers and for the public. These recommendations and much of the guidance provided by these organizations have usually been adopted by regulatory bodies around the world. In the case of the NCRP, the levels have fallen from 0.1 roentgen per day in 1934 to the current 5 rem per year (a factor of about 5). The present levels recommended by both the ICRP and the NCRP correspond to reasonable levels of risk where the risks of harm from ionizing radiation are compared with the hazards of other, commonly regarded, as safe, industries. Some considerations for the future in radiation protection include trends in exposure levels (generally downward for the average exposure to workers) and improvements in risk estimation; questions of lifetime limits, de minimis levels, and partial body exposures; plus problems of high LET radiations, acceptability of risk, synergisms, and risk systems for protection.

Adult↗
PubMed1993

[Radiation protection effects of sinapine on Drosophila melanogaster in a sex-linked recessive lethal test system].

It has been shown that the radiation resistance of some cruciferous plants is related to some natural radiation protection substances in these plants. Sinapine, which has shown radiation protection effects on barley, wheat and mouse, is one of such substances distributed in cruciferous plants. In this paper, the radiation protection effects of sinapine on Drosophila melanogaster in a sex-linked recessive lethal (SLRL) test system were observed. The sinapine solution could be fed to the D. melanogaster (Oregon K). 40 Gy X-irradiation induced SLRL mutation rate of 8.96%. However, if 10 mg/ml sinapine which was found to have no physiological toxicity or harmful effects on its reproductive function, was fed before 40 Gy X-irradiation, the SLRL mutation rate could be reduced to 0.40%, which was within the range of spontaneous SLRL mutation rate of Oregon K Drosophila, i.e. 0-0.4%. The potential of the using of the very strong radiation protection effects of sinapine in anticarcinogenesis was also discussed.

Animals↗
PubMed1986

Radiation protection programs in nuclear medicine.

The development of radiation protection programs in nuclear medicine has been stimulated by the greater degree of regulation that exists in this form of medical imaging. A program within an institution will depend on the amount and type of work to be undertaken, the resources available, and the commitment of the individuals involved. These factors may be part of a licensing program or exist within a broader framework. General policy may be set forth in a manual or guidelines distributed to all employees. The continuing review and development of policy is the function of the institutional committee on radiation. This review must consider patients and workers with the objective of reducing overall dose while obtaining the maximum amount of clinical information. The responsibility for radiation protection is shared by the institution, the licensee, and the individual employee.

Humans↗
PubMed1989

Three example applications of optimization techniques to Department of Energy contractor radiation protection programs.

Six numerical examples of optimization of radiation protection are provided in the appendices of International Commission on Radiological Protection (ICRP) Publication No. 37 (1983). In each case, the calculations were based on well-defined parameters and assumptions. In this paper, we examined three different numerical examples that were based on empirical data and less-certain assumptions. In the first example, the optimum sampling frequency for a typical 3H bioassay program was found to be once every 2 mo. However, this result depended on assumed values for several variables that were difficult to evaluate. The second example showed that the optimum frequency for recalibrating a group of "cutie pie" (CP) ionization chamber survey instruments was once every 85 d. This result depended largely on the assumption that an improperly operating CP instrument could lead to a serious overexposure. In the third example, one continuous air monitor (CAM) was determined to be the optimum number in a workplace at a Department of Energy (DOE) Pu facility. The optimum location of the CAM was determined from past glove-box release studies. These examples demonstrated that cost-benefit analysis of individual elements of radiation protection programs can be useful even if limited data are available.

Air Pollution, Radioactive↗
PubMed1996

The use of cell-oriented factors and the hit size effectiveness function in radiation protection.

It has long been argued that ionizing radiation can be considered to interact with matter in discrete, randomly occurring energy transferring events ("hits") and that the resulting microscopically nonuniform pattern of energy deposition strongly influences the biological effect of a given exposure. Microdosimetric measurements combined with cellular biological response data in the form of a "hit size effectiveness function" (HSEF) suggest a possible cell-oriented alternative method of correlating exposure with effect at low levels of any radiation or mixture of radiations. The instrumentation required, the validity of the approach, and its practical usefulness in radiation protection are examined, and its application to space radiation exposure is proposed as a test case.

Aerospace Medicine↗
PubMed2006

Regulatory aspects of radiation protection.

The paper introduces the projects launched by the European Community to foster prospects in dosimetry, radiation protection and best use of equipment in the medical field. These projects are put in perspective with the European legal framework for radiation protection, in particular, the Basic Safety Standards Directive, the Medical Exposures Directive and the Directive on High-Activity Sealed Sources. A summary is given of the overall mission statements of the commission services in the field of radiation protection, including the field of research, and how they relate to other actions in the overall health policy of the EU. In conclusion, a number of priority areas for future work in the medical field are highlighted.

European Union↗
PubMedDate not supplied

Analysis of radiation scatter during angiographic procedures: evaluation of a phantom model and a modified radiation protection system.

PURPOSE: To study the radiation scattering associated with the digital subtraction angiography (DSA) unit in angiographic procedures and to design an effective radiation protection shield based on these data. MATERIALS AND METHODS: The number of scattered photons was measured at three points relative to the operator's position. Anteroposterior abdominal and lateral cranial fluoroscopy were evaluated. As protective devices, a lead curtain, sliding shields, and a brim-shaped image intensifier (II) hood were designed. RESULTS: In abdominal fluoroscopy, radiation was found to scatter to the operator's lower limbs from the underside of the catheter table, to the abdomen from the side of the patient's body, and to the head and neck from the table surface adjacent to the patient. The use of protective devices reduced exposure from 2.89 to 0.058 mR/min for the operator's lower limbs, from 0.987 to 0.069 mR/min for the operator's abdomen, and from 0.696 to 0.139 mR/ min for the operator's head and neck area. With lateral cranial fluoroscopy, radiation was detected to scatter to the operator's lower limbs from the underside of the catheter table, to the abdomen from the patient's temporal area, and to the head and neck from the patient's face. The use of protective devices reduced exposure from 0.248 to 0.010 mR/min for the operator's lower limbs, from 0.129 to 0.010 mR/min for the operator's abdomen, and from 0.162 to 0.018 mR/min for the operator's head and neck area. CONCLUSIONS: The characteristic directions of scattering to the operator were identified. An effective modified radiation protection system was designed based on this information.

Abdomen↗
PubMed1992

Sulfur compounds in therapy: radiation-protective agents, amphetamines, and mucopolysaccharide sulfation.

OBJECTIVE: Sulfur-containing compounds have been used in the search for whole-body radiation-protective compounds, in the design of amphetamine derivatives that retain appetite-suppressive effects but lack most behavioral effects characteristic of amphetamines, and in the search for the cause of kidney stone formation in recurrently stoneforming patients. METHODS: Organic synthetic procedures were used to prepare radiation-protective compounds having a variety of sulfur-containing functional groups, and to prepare amphetamine derivatives having electron-attracting sulfur functions. In the case of the kidney stone causation research, isolation of urinary mucopolysaccharides (MPS) from recurrently stoneforming patients was carried out and the extent of sulfation of the MPS was determined by electrophoresis. RESULTS: Whole-body radiation-protective agents with a high degree of protection against lethal doses of gamma-radiation in mice were found in a series of quinolinium and pyridinium bis(methylthio) and methylthio amino derivatives. Mechanism studies showed that the copper complexes of these agents mimicked the beneficial action of superoxide dismutase. Electron-attracting sulfur-containing functions on amphetamine nitrogen, as well as 4'-amino nitrogen provided amphetamine derivatives with good appetite-suppressant effects and few or no adverse behavioral effects. Higher than normal levels of sulfation of the urinary MPS of stone formers suggested a cause for recurrent kidney stone formation. A sulfation inhibitor was found to prevent recurrence of stone formation and inhibit growth of existing stones. CONCLUSIONS: The inclusion of various sulfur-containing functions in organic molecules yielded compounds having whole-body radiation protection from lethal doses of gamma-radiation in animals. The presence of electron-attracting sulfur functions in amphetamine gave derivatives that retained appetite-suppressant effects and eliminated most adverse behavioral effects. A therapy for recurrent urolithiasis resulted from inhibition of MPS sulfation, after the finding that stoneforming patients had abnormally high levels of MPS sulfation.

Amphetamines↗
PubMed2000

Radiation protection by the ocimum flavonoids orientin and vicenin: mechanisms of action.

In previous studies, flavonoids, orientin and vicenin, that were isolated from the leaf extract of Ocimum sanctum, were found to protect mice against radiation injury. Several flavonoids are known to be good antioxidants. Therefore, the effect of orientin and vicenin on radiation-induced lipid peroxidation in vivo and their antioxidant activity in vitro were studied. Adult mice were injected intraperitoneally with 50 microgram/kg of orientin or vicenin and exposed whole-body to 3 Gy of gamma radiation. Lipid peroxidation was measured in the liver 15 min to 8 h postirradiation. The antioxidant activity of orientin/vicenin (10-500 microM) was studied by measuring inhibition of hydroxyl radicals generated by the Fenton reaction (Fe(3+)-EDTA-ascorbic acid-H(2)O(2)) in vitro. The compounds were also tested for possible pro-oxidant and iron chelation activities at the above concentrations in the in vitro system. Orientin and vicenin provided almost equal protection against radiation-induced lipid peroxidation in mouse liver. Both compounds showed a significantly greater free radical-inhibiting activity in vitro than DMSO. Neither orientin nor vicenin showed any pro-oxidant activity at the concentrations tested. Both compounds inhibited free radical formation in the absence of EDTA. Free radical scavenging appears to be a likely mechanism of radiation protection by these flavonoids.

Animals↗
PubMed2006

Training of interventional cardiologists in radiation protection--the IAEA's initiatives.

The International Atomic Energy Agency (IAEA) has initiated a major international initiative to train interventional cardiologists in radiation protection as a part of its International Action Plan on the radiological protection of patients. A simple programme of two days' training has been developed, covering possible and observed radiation effects among patients and staff, international standards, dose management techniques, examples of good and bad practice and examples indicating prevention of possible injuries as a result of good practice of radiation protection. The training material is freely available on CD from the IAEA. The IAEA has conducted two events in 2004 and 2005 and number of events are planned in 2006. The survey conducted among the cardiologists participating in these programmes indicates that over 80% of them were attending such a structured programme on radiation protection for the first time. As the magnitude of X-ray usage in cardiology grows to match that in interventional radiology, the standards of training on radiation effects, radiation physics and radiation protection in interventional cardiology should also match those in interventional radiology.

Cardiology↗
PubMed2001

Response of radiation protection dosemeters in mixed high-energy photon and electron radiation fields.

The response of radiation protection dosemeters in terms of the phantom-related operational quantities Hp(10) and H'(10.0 degrees) was measured for personal and area monitoring systems in mixed high-energy electron and photon radiation fields with energies up to 7 MeV. Using mixed radiation fields composed of different fractions of charged particle and photon fluence, three conditions were produced at the point of measurement: charged particle equilibrium (CPE) (a), a lack (b) and an excess (c) of charged particles relative to the conditions of CPE. Personal and area dosemeters of different types were investigated under conditions (a)-(c). A large variability of the response of the different dosemeter types was observed. The results are presented and discussed.

Air Pollution, Radioactive↗
PubMed1995

Radiation protection recommendations on dose limits: the role of the NCRP and the ICRP and future developments.

The purpose of this paper is to review the role of the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP) in making recommendations on dose limits for ionizing radiation exposure for workers and for the public. The text describes the new limits for workers and public recommended by ICRP in 1991 and NCRP in 1993 and the composition of the radiation health detriment on which they are based. The main component of this detriment is the risk of radiation induced cancer which is now estimated to be about three times greater than a decade or so earlier. Uncertainties in these risk estimates are discussed. Some special radiation protection problems, such as those for the embryo or fetus are described. The article also addresses future progress in radiation protection particularly with regard to future improvements in the scientific basis for radiation protection recommendations.

Environmental Exposure↗
PubMed1994

[A new radiation protection device for cardiologists active in interventional radiology].

The radiation protection system up to now has been in the form of a lead glass pane and a lead curtain on the examination table. As new equipment we used a leaded rubber cover (Pb 0.75 mm) extending from the foot to the rib cage of the patient and a 60-cm high and 70-cm wide stand, reinforced with leaded rubber (Pb 1.0 mm) fixed onto the foot switch. During the period of 2 months the total radiation dose in 156 coronary angioplasties and 71 diagnostic heart catheterizations was measured on the hand, thorax, lower leg and foot of the examiner using ring and placet dosimeters. The dose was measured for a further 2 months, during 152 coronary angioplasty and 66 diagnostic heart catheterizations without the new extra radiation protection equipment. The catheterization procedure was not basically impeded through the lead cover and the lead stand. The radiation dose experienced by the examiner was reduced by 96.8% on the hand, 98.6% on the thorax, 98.8% on the lower leg, and by 99.5% on the foot.

Angioplasty, Balloon, Coronary↗
PubMed1999

Radiation protection concepts and quantities for the occupational exposure to cosmic radiation.

For the purposes of dose limitation and dose control, the harm, or detriment, of exposure to radiation is assessed by the quantity effective dose. Effective dose is evaluated by the application of factors to the averaged absorbed dose in the organs and tissues of the body. Radiation monitoring instruments are generally calibrated in terms of the quantity ambient dose equivalent which is defined in a simple spherical phantom. The relationship of these quantities is described. Requirements for the radiation protection of aircraft crew are given in the European Union Council Directive 96/29/EURATOM. There are requirements to assess the exposure of aircraft crew, to inform them of health risks, to reduce higher doses, and to control the dose to the fetus. There are no explicit dose limits, other than a dose objective to be applied to the exposure of the fetus, and no requirements for designation of areas or classification of workers. There are significant differences between the exposure condition of aircraft crew and workers in most other industries where there is occupational exposure to radiation. There are greater ranges of radiation types and energy, and there are different dose distributions and characteristics of the working populations. However, the field intensity is predictable and, with the exception of rare solar events, there is no risk of significant unexpected exposures. Dose assessment is anticipated to be by folding staff roster information with estimates of route doses, since there is little variability of dose rate within an aircraft. Route doses, which may be either an agreed average value for a given airport pairing and aircraft type, or be flight specific, will be closely linked to measured values. Requirements as to the accuracy of dose assessment should be applied which are broadly similar to those used in individual monitoring generally.

Aerospace Medicine↗
PubMed2004

Radiation protection challenges facing the federal agencies.

In the United States, federal agencies are responsible for setting national policy and performance expectations for radiation protection programs. National policy establishes a regulatory regime, under which society can realize the beneficial uses of radiation while at the same time protecting workers, the public, and environment from the potential hazards of radiation. The challenges facing federal agencies continue to revolve around finding the right balance between benefit and adverse impact. Federal agencies are petitioned to support the research community to provide a sound scientific basis for informing the decision-making process related to radiation protection policy. The federal agencies are further challenged to consider the deliberations of the International Commission on Radiological Protection (ICRP) and the National Council on Radiation Protection and Measurements (NCRP) who bring together the best technical minds in the field to consider the latest scientific information and provide recommendations for establishing comprehensive and coherent radiation protection programs. The uncertainty inherent in research and the conservatism in the models and recommendations of the ICRP and NCRP should be transparent and communicated because determining the level of uncertainty and the degree of conservatism acceptable to society is a challenge for, and the responsibility of, the federal agencies in creating performance-based policies in public health and radiation protection. It is through the federal government's open, inclusive, and democratic processes where society strikes the balance that defines adequate radiation protection policy, builds public trust, and allows the radiation protection professionals to properly implement and manage that policy.

Federal Government↗