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PubMed1999

[Radioactivity in Harz area drinking water after Chernobyl].

After the reactor accident in Chernobyl on April 26th, 1986 drinking water pollution was in Lower Saxony a problem in the Harz mountains. With the rainout of the radioactive clouds radioactivity came into the water-barrages, brooks und pools for drinking water supply. Good drinking water management supervised by the district community physician limited radioactive nuclides in drinking water. Drinking water path was approximately only 5% of the exposure to radioactive nuclides in the Harz region due to Chernobyl in 1986.

Germany↗
PubMed2005

[Loss and uncontrolled use of radioactive sources].

In the course of history, exposure to radioactive sources escaping regular control, has been the main cause of fatal accidents, with the exception of the reactor accident at Chernobyl. After the disintegration of the Soviet Union, numerous lost sources have been found, sometimes with serious physical damage. The attacks of September 11, 2001 have focussed the attention on the possibility of nuclear terrorism. Although the risks of fatal consequences are rather limited, the possible uncontrolled exposure to ionizing radiation has an important psycho-social impact on the population. After a brief survey of the types of radioactive sources for medical and industrial applications and a discussion of the risks and exposure routes, possible scenarios are illustrated by well documented case histories. The main conclusions of this analysis are: Radioactive materials are not unique as a potential threat by toxic materials. The most serious consequences for individuals occur as the result of external radiation, mostly with skin contact with medium-active sources which are relatively easily accessible. The collective impact is mostly psycho-social and is more important for a dispersed contamination of the environment. Many sources are detected via medical complaints. The knowledge of the specific symptoms is consequently very important. A dispersion of radioactive contamination has usually considerable economic consequences. Accidents occur particularly, but certainly not exclusively, in relatively unstable countries. Change of owner or final evacuation of the source constitute a critical phase in many scenarios.

Humans↗
PubMed1992

Genetic consequences of radioactive contamination for populations of Arabidopsis.

Populations of Arabidopsis thaliana (L.) Heynh. growing within a 30 km radius of Chernobyl and characterized by radioactive contamination levels ranging from 0.02 to 240 mR h-1 were analyzed for the frequency of embryonic lethal mutations in 1987 and 1988. Plots that retained high levels of radioactive contamination long after the initial exposure were characterized by a high frequency of mutant plants. Plots with low levels of radioactive contamination, which were significantly reduced soon after exposure, were characterized by a decrease in the initially high proportion of mutant plants. Populations of Arabidopsis exposed to insignificant radioactive contamination showed no increase in the frequency of mutant plants; mutation levels were comparable to those found in control plants.

Accidents↗
PubMed2006

Recent trends and developments in dialogue on radioactive waste management: experience from the UK.

This paper highlights some recent trends and developments in dialogue on radioactive waste management in the UK. In particular, it focuses on the use of dialogue around options for the management of risk, and describes techniques for stakeholder dialogue in the field of radioactive waste management. The paper summarises past and on-going experience in the UK, and provides an overview of some practical examples from decommissioning of the former reprocessing facility at Dounreay in Scotland. In common with developments and trend in other countries, the UK has moved to a position where there is now widespread recognition that radioactive waste management requires not only sound technical assessment of risk, but also public participation, consultation and stakeholder dialogue on proposed solutions and the associated risks. In fact, the shift of position has arguably been quite pronounced, with formal procedures to identify, clarify and integrate stakeholders' issues and concerns within the decision-making processes. Experience suggests that citizens are capable of engaging with complex technical issues such as radioactive waste. Indeed, the earlier in the decision-making process that public and stakeholder engagement (PSE) occurs--for example, on the consideration of options and alternatives--the greater the chance of reaching a successful outcome that properly reflects the values and opinions of stakeholders. In the UK, the assessment of alternative waste management options is increasingly being addressed through Best Practical Environmental Option (BPEO) studies. Responses to stakeholder engagement processes and experience of conducting BPEO studies emphasise that consultation must be open, transparent, deliberative and inclusive. However, while early consideration of generic approaches and option choices is necessary to generate a climate of openness and understanding, it remains essential to fully engage with local stakeholder and community groups to consider issues associated with proposed developments at a site-specific level. An interesting area where further attention may be warranted is the use in final decision-making of the results from participatory processes such as BPEO studies. Demonstrating clearly that participants' views have influenced decisions appears to be essential for retaining legitimacy and trust, confidence and goodwill.

Community Participation↗
PubMed1986

Institutional storage and disposal of radioactive materials.

Storage and disposal of radioactive materials from nuclear medicine operations must be considered in the overall program design. The storage of materials from daily operation, materials in transit, and long-term storage represent sources of exposure. The design of storage facilities must include consideration of available space, choice of material, occupancy of surrounding areas, and amount of radioactivity anticipated. Neglect of any of these factors will lead to exposure problems. The ultimate product of any manipulation of radioactive material will be some form of radioactive waste. This waste may be discharged into the environment or placed within a storage area for packaging and transfer to a broker for ultimate disposal. Personnel must be keenly aware of packaging regulations of the burial site as well as applicable federal and local codes. Fire codes should be reviewed if there is to be storage of flammable materials in any area. Radiation protection personnel should be aware of community attitudes when considering the design of the waste program.

Drug Storage↗
PubMed1988

Radioactive artifacts: historical sources of modern radium contamination.

Radium has been distributed in a wide variety of devices during the early part of this century. Antique objects containing significant amounts of radium turn up at flea markets, antique shows, and antique dealers, in a variety of locations. These objects include radium in devices which were used by legitimate medical practitioners for legitimate medical purposes such as therapy, as well as a wide variety of "quack cures." These devices may contain anywhere from a few nanocuries to as much as several hundred microcuries of radium. In addition to medical sources, a large variety of scientific instruments utilize radium in luminous dials. These instruments include compasses, azimuth indicators, and virtually any object which might require some form of calibration. In addition, the consumer market utilized a large amount of radium in the production of wrist watches, pocket watches, and clocks with luminous dials. Some of these watches contained as much as 4.5 microCi of radium, and between 1913 and 1920 about 70 gm was produced for the manufacture of luminous compounds. In addition to the large amount of radium produced for scientific and consumer utilization, there were a number of materials produced which were claimed to contain radium but in fact did not, further adding to the confusion in this area. The wide availability of radium is a result of the public's great fascination with radioactivity during the early part of this century and a belief in its curative properties. A number of objects were produced in order to trap the emanations of radium in water for persons to drink in order to benefit from their healing effects. Since the late 20s and early 30s the public's attitude towards radiation has shifted 180 degrees and it is now considered an extremely dangerous and harmful material. However, even as late as the 1950s, there were still some items produced containing radioactivity which today would be unthinkable. The "Buck Rogers Mystery Ring" of the 1950s was activated with polonium. With the shift in public attitudes towards radioactivity, and increasing problems in disposal of radioactive materials, the disposal of radium presents a particularly perplexing problem. The radium which was produced in the early part of the century is still around in various forms and is extremely difficult to dispose of. All objects discovered claiming to contain radium should be taken seriously and should be properly surveyed.(ABSTRACT TRUNCATED AT 400 WORDS)

Equipment and Supplies↗
PubMed1996

Becquerel and the discovery of radioactivity: early concepts.

It has been 100 years since Becquerel discovered radioactivity shortly after he learned of Roentgens discovery of x-rays at a meeting of the French Academy of Science. His discovery in 1896 was a direct consequence of his work and that of his father and grandfather on phosphorescence and fluorescence. It resulted from the serendipitous use of uranium salts, which have known phosphorescent properties, to reproduce Roentgen rays with the mistaken notion that they were a related phenomenon. Intense investigation by Becquerel and others rapidly revealed the differences in these radiations and led to the discovery of beta, alpha, and gamma rays and the properties of radioactivity in numerous other substances. The work of Becquerel was acknowledged by Madame Curie to be the primary influence on the direction of her thesis toward the work that led to the isolation of radium and the introduction by her of the term radioactivity to describe these phenomena. Although the unit of radioactivity is now called the Becquerel in acknowledgement of his accomplishments, few people, even in the nuclear medicine field, are fully aware of the breadth and importance of his work. This article hopefully will help to resolve this.

France↗
PubMedDate not supplied

Prevalence of radioactive signals from surveillance of an emergency department.

INTRODUCTION: Since the 11 September 2001 terrorist attacks in the United States, concerns have been raised regarding the threat of a radiological terrorist weapon. Although the probability of the employment of a nuclear device is remote, the potential of a radiological dispersal device (RDD) or "dirty bomb" is of concern. While it is unlikely that such a device would produce massive numbers of casualties, it is far more likely that it would result in public panic and perhaps even disable the local healthcare system. The utility of surveillance with radiation detectors in the healthcare setting has not been fully evaluated. OBJECTIVE: The objective of this study was to characterize the prevalence of radioactive sources entering an urban emergency department (ED). METHODS: A retrospective review of data obtained from a radiation detector positioned to detect radioactive people entering an ED of an urban academic hospital that serves 45,000 patients/year was performed. Graphical outputs of radioactivity were recorded in Microsoft Excel (Microsoft, Redmond, WA, US) spreadsheets in microREM/hour. Data were collected continuously from 22 December 2003 to 22 January 2004. An event was defined as any elevation in radiation levels >95% confidence interval from the mean level of background radiation over 72 hours (h). RESULTS: A total of 215 events were observed over a 28-day period, with a mean value of 7.7 events/day, and a maximum of 15 events/day. During the 28-day period, the baseline mean level of background radiation was 2-4 microREM/h. Readings ranged from 2,148.28-17,292.25 microREM/h with a maximum sustained detector exposure of 684.37 microREM. Distinct signal patterns were seen at both detectors including tonic, phasic, dual, and short duration spikes. CONCLUSION: The number of radioactive signals detected from persons entering the ED was much higher than expected. While the vast majority of these signals pose no health threat, they may make routine screening for a radiological terrorist event difficult. Further study is needed to determine this correlation.

Air Pollution, Radioactive↗
PubMed2005

Evaluating factors affecting the permeability of emulsions used to stabilize radioactive contamination from a radiological dispersal device.

Present strategies for alleviating radioactive contamination from a radiological dispersal device (RDD) or dirty bomb involve either demolishing and removing radioactive surfaces or abandoning portions of the area near the release point. In both cases, it is imperative to eliminate or reduce migration of the radioisotopes until the cleanup is complete or until the radiation has decayed back to acceptable levels. This research investigated an alternative strategy of using emulsions to stabilize radioactive particulate contamination. Emergency response personnel would coat surfaces with emulsions consisting of asphalt or tall oil pitch to prevent migration of contamination. The site can then be evaluated and cleaned up as needed. In order for this approach to be effective, the treatment must eliminate migration of the radioactive agents in the terror device. Water application is an environmental condition that could promote migration into the external environment. This research investigated the potential for water, and correspondingly contaminant, migration through two emulsions consisting of Topein, a resinous byproduct during paper manufacture. Topein C is an asphaltic-based emulsion and Topein S is a tall oil pitch, nonionic emulsion. Experiments included water adsorption/ mobilization studies, filtration tests, and image analysis of photomicrographs from an environmental scanning electron microscope (ESEM) and a stereomicroscope. Both emulsions were effective at reducing water migration. Conductivity estimates were on the order of 10(-80) cm s(-1) for Topein C and 10(-7) cm s(-1) for Topein S. Water mobility depended on emulsion flocculation and coalescence time. Photomicrographs indicate that Topein S consisted of greater and more interconnected porosity. Dilute foams of isolated spherical gas cells formed when emulsions were applied to basic surfaces. Gas cells rose to the surface and ruptured, leaving void spaces that penetrated throughout the emulsion. These experiments indicate that emulsions may be a viable means for containing RDD residuals; however, improvements are needed for optimal performance.

Adsorption↗
PubMed2000

Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments.

We have developed a radiation resistant bacterium for the treatment of mixed radioactive wastes containing ionic mercury. The high cost of remediating radioactive waste sites from nuclear weapons production has stimulated the development of bioremediation strategies using Deinococcus radiodurans, the most radiation resistant organism known. As a frequent constituent of these sites is the highly toxic ionic mercury (Hg) (II), we have generated several D. radiodurans strains expressing the cloned Hg (II) resistance gene (merA) from Escherichia coli strain BL308. We designed four different expression vectors for this purpose, and compared the relative advantages of each. The strains were shown to grow in the presence of both radiation and ionic mercury at concentrations well above those found in radioactive waste sites, and to effectively reduce Hg (II) to the less toxic volatile elemental mercury. We also demonstrated that different gene clusters could be used to engineer D. radiodurans for treatment of mixed radioactive wastes by developing a strain to detoxify both mercury and toluene. These expression systems could provide models to guide future D. radiodurans engineering efforts aimed at integrating several remediation functions into a single host.

Bacterial Proteins↗
PubMed1983

Measurement of specific radioactivities in labelled hormones by self-displacement analysis.

A graphical method is described that allows the determination of specific radioactivities of radioactively labelled hormones. This method combines the self-displacement technique, plotting bound/free ratios versus mass of unlabelled hormone or total radioactivity of labelled preparation added to the receptor preparation, and the maximal binding capacity of the labelled hormone. The procedure presented herein provides a more realistic specific radioactivity for use in all binding experiments. Application of the method is demonstrated for 125I-labelled ovine prolactin, and data are presented for 125I-labelled human choriogonadotropin and [3H]testosterone.

Animals↗
PubMed1989

Reduction of airborne radioactive dust by means of a charged water spray.

An electrostatic precipitator based on charged water spray technology has been used in an underground uranium mine to control long-lived radioactive dust and short-lived aerosol concentration in a mine gallery where dust from a rock breaking/ore transportation operation was discharged. Two main sampling stations were established: one upstream of the dust precipitator and one downstream. In addition, dust samplers were placed at different locations between the dust discharge and the end of the mine gallery. Long-lived radioactive dust was measured using cascade impactors and nylon cyclone dust samplers, and measurement of the radioactivity on the samples was carried out by conventional methods. Radon and thoron progeny were estimated using standard techniques. Experiments were conducted under a variety of airflow conditions. A maximum radioactive dust reduction of about 40% (approximately 20% caused by gravitational settling) at a ventilation rate of 0.61 m3/sec was obtained as a result of the combined action of water scrubbing and electrostatic precipitation by the charged water spray electrostatic precipitator. This represents the optimum efficiency attained within the range of ventilation rates investigated. The dust reduction efficiency of the charged water spray decreased with increasing ventilation rate, i.e., decreasing air residence time, and hence, reduced dust cloud/charged water droplets mixing time.

Air Pollutants, Occupational↗
PubMed2004

Gender, politics, and radioactivity research in interwar Vienna: the case of the Institute for Radium Research.

This essay explores the significance of political and ideological context as well as experimental culture for the participation of women in radioactivity research. It argues that the politics of Red Vienna and the culture of radioactivity research specific to the Viennese setting encouraged exceptional gender politics within the Institute for Radium Research in the interwar years. The essay further attempts to provide an alternative approach to narratives that concentrate on personal dispositions and stereotypical images of women in science to explain the disproportionately large number of women in radioactivity research. Instead, the emphasis here is on the institutional context in which women involved themselves in radioactivity in interwar Vienna. This approach places greater importance on contingencies of time and place and highlights the significance of the cultural and political context in a historical study while at the same time shedding light on the interrelation between scientific practices and gender.

Academies and Institutes↗
PubMed2003

Early detection of radioactive fallout by gamma spectrometry.

Radioactive fallout should be detected as early as possible. A new and efficient method for detection of low-level irradiation from manmade radioactivity is developed. Radiation abnormalities are detectable down to air kerma rates of 0.5 to 1.0 nGy h(-1) for 137Cs and even lower for 131I. For multi-gamma energy radioactivity the detection level is 2.6-3.5 nGy h(-1). A standard NaI detector and a 512-channel analyser are used together with noise adjusted singular value decomposition (NASVD). Statistical noise is removed and the measured spectra are reproduced using spectral components produced by NASVD. Stripping is not used and false alarms due to washout of atmospheric radon progeny are almost eliminated. Detection levels and the criteria for setting warning and alarm levels are discussed. The method may also be useful in other situations, for example where low-level signals from radioactive sources need to be detected.

Algorithms↗
PubMed2006

Natural radioactivity intake into wheat grown on fertilized farms in two districts of Pakistan.

The use of phosphate fertilizers on agricultural farms enhances gamma-ray activity concentration in the farms and therefore absorbed dose rates to the public. The most common natural radionuclides in fertilizer and soil are (40)K, (226)Ra and (232)Th. Agricultural farms at four locations in two districts in Pakistan consisting of saline and normal soils had been under fertilizer treatment for the past 30, 20, 10 and 0 y, therefore, natural radioactivity has been measured in soil samples from these sites to investigate the effect of fertilizers in soil and wheat grown in these sites. Radioactivity measured in soil of the sites under investigation was 550-644, 20-35 and 42-58 Bq kg(-1) for (40)K, (226)Ra and (232)Th, respectively. Wheat was grown in the farms and radioactivity transferred from soil to roots, shoots and grains was also measured. Relatively high natural radioactivity has been observed in the fertilized agricultural farms and in the wheat plants grown in these farms. From the total amount of an element uptaken in a plant, distribution of the element in different parts of the plant has been studied. The distribution of potassium was almost uniform in roots, shoots and grains of wheat; that of radium was different in the three parts of wheat; and that of thorium was almost equal in shoots and grains but quite large in the roots. Soils to grain transfer factors of the natural radionuclides have been determined as 3-4 x 10(-2) for (226)Ra, 2-3 x 10(-2) for (232)Th and 17-20 x 10(-2) for (40)K. Annual doses of (40)K and (226)Ra received by intake of grain products have been estimated to lie within range while the dose received from intake of (232)Th is larger than the range specified in UNSCEAR report 2000.

Environmental Exposure↗
PubMed1989

Destruction of genotoxic wastes mixed with radioactive products.

Before their disposal, genotoxic substances are destroyed by strong oxidizing agents. If there are molecules labelled with radionuclides in the medium which is oxidized, then this treatment may bring about the release of gaseous radioactive compounds. We have looked for evidence of such a release following the action of K permanganate and sodium hypochlorite on molecules labelled with 3H, 14C, 32P, and 125I. Among the compounds examined, only those labelled with 14C showed significant quantities of radioactive gas released, with values up to 60% of the total radioactivity. For the other products, less than 0.6% of the radioactivity appeared in a volatile form.

Gases↗
PubMed1994

Residual long-lived radioactivity distribution in the inner concrete wall of a cyclotron vault.

We measured the depth distribution of residual long-lived radioactivity in the inner concrete wall of a cyclotron vault by assaying concrete cores and we estimated the neutron flux distribution in the inner concrete wall by means of activation detectors. Nine long-lived radioactive nuclides (46Sc, 59Fe, 60Co, 65Zn, 134Cs, 152Eu, 154Eu, 22Na, and 54Mn) were identified from the gamma-ray spectra measured in the concrete samples. It was confirmed that the radionuclides induced by thermal neutrons through the (n, gamma) reaction are dominant, and that the induced activity by thermal neutrons is greatest at a depth of 5 to 10 cm rather than at the surface of the concrete and decreases exponentially beyond a depth of about 20 cm. By comparing the radioactivity and neutron flux distributions, we can estimate the induced long-lived radioactivity in concrete after a long period of operation from the short-term activation measurement.

Construction Materials↗
PubMed1998

Radiation exposure modeling for apartment living spaces with multiple radioactive sources.

Since late 1992, over 100 building complexes in Taiwan, including both public and private schools, and 1,000 apartments have been identified as emitting elevated levels of gamma-radiation. These high levels of gamma-radiation have been traced to construction steel contaminated with 60Co. Accurate reconstruction of the radiation exposure dosage among residents is complicated by the discovery of multiple radioactive sources within the living spaces and by the lack of comprehensive information about resident life-style and occupancy patterns within these contaminated spaces. The objective of this study was to evaluate the sensitivity of current dose reconstruction approach employed in an epidemiological study for the health effects of these occupants. We apply a statistical method of local smoothing in dose rate estimation and examine factors that are closely associated with radiation exposure from multiple radioactive sources in the apartment. Two examples are used, a simulated measurement in a hypothetical room with three radioactive sources and a real apartment in Ming-Shan Villa, one of the contaminated buildings. The simulated and estimated means are compared along 5-10 selected points of measurement: by local smoothing approach, with the furniture-adjusted space, and with the occupancy time-weighted mean. We found that the local smoothing approach came much closer to theoretical values. The local smoothing approach may serve as a refined method of radiation dose distribution modeling in exposure estimation. Before environmental exposure assessment, "highly occupied zones" (HOZs) in the contaminated spaces must be identified. Estimates of the time spent in these HOZs are essential to obtain accurate dosage values. These results will facilitate a more accurate dose reconstruction in the assessment of residential exposure in apartments with elevated levels of radioactivity.

Air Pollution, Radioactive↗