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PubMed2003

Reconstruction of the radionuclide spectrum of liquid radioactive waste released into the Techa river in 1949-1951.

The major part of the liquid radioactive waste released by the Mayak Production Association (PA) radiochemical plant into the Techa river occurred in 1949-1951, but there is information on only one single radiochemical analysis of a water sample taken on 24 and 25 September 1951. These data are here used to assess the spectrum of radionuclides that were released between 1949 and 1951. For this purpose, details of the radiochemical methods of radionuclide extraction and radiometric measurements of beta-activity used at Mayak PA in the 1950s have been taken into account. It is concluded that the data from the radiochemical measurements agree with the theoretical composition of fission products in uranium after exposure times in the reactor (120 days) and subsequent hold times (35 days) that were typical for the procedures at that time. The results of the analysis are at variance with assumptions that underlie the current Techa river dosimetry system. They confirm the conclusion that the external doses to the Techa river residents in the critical period up to 1952 were predominantly due to short-lived fission products.

Beta Particles↗

PubMed1992

Effects of radioactive fallout on soil animal populations in the 30 km zone of the Chernobyl atomic power station.

Studies were carried out during July and September 1986, April 1987, and October 1988. Radioactive fallout after the Chernobyl atomic power station (APS) accident induced catastrophic effects on populations of small pine-litter faunae within the 3 km zone around the station. Effects on soil faunae were not so marked due to shielding by the soil, or on litter faunae at the edge of the 30 km zone due to distance from the source. Thirty-gray doses did not directly affect adult animals in the soil and litter, but impacted their eggs and juveniles. Resident populations recovered slowly during the first year after the accident. Insect migration into the contaminated area was the primary source of soil animal population recovery. After 2-2.5 years, marked differences between populations in the contaminated and control areas were no longer found.

Accidents↗

PubMed1994

Cs-137 content in the mushrooms of radioactive contaminated zones of the European part of the CIS.

Samples of different species of mushrooms were collected in the forests contaminated by Chernobyl (ChNPP) accident fallout debris. Sampling sites were located at a distance of 5-200 km from Chernobyl NPP. Transfer factors (TF) for Cs-137 from soil to mushrooms varied from 12 to 5060 nCi kg-1/Ci km-2; TF variability depended on the distance from ChNPP, mushroom species and growth conditions. The highest concentrations of Cs-137 were observed in Paxillus involutus and Xerocomus badius. These species are suggested as bioindicators of radioactive contamination.

Basidiomycota↗

PubMed2005

Natural radioactivity levels in granitic plutons and groundwaters in Southeast part of Eskisehir, Turkey.

The present work investigated the radioactivity level of the granitoid plutons and its effect on the groundwaters in the southeast part of Eskisehir. Fourteen granitic samples from the Kaymaz and Sivrihisar plutons and 11 groundwater samples from the near vicinity of the pluton were analyzed. The activity concentrations measured for (238)U and (232)Th ranged from 43.59+/-2 to 651.80+/-24 Bq/kg, and 51.16+/-3 to 351.94+/-13 Bq/kg, respectively. The activity concentrations obtained for (40)K varied from 418.50+/-17 to 1618.03+/-66 Bq/kg. The absorbed dose rates in air outdoors ranged from 87.14 to 531.81 nGy/h. All the results obtained from the Kaymaz pluton are higher than those from the Sivrihisar. The U (ave. 16.6 ppm) and Th (ave. 49.9 ppm) values of the Kaymaz pluton are higher than the average concentrations of the magmatic rocks of granitic composition. These results are consistent with high dose rates of the pluton. The gross-alpha activities in the groundwater samples ranged from 0.009 to 1.64 Bq/l and the gross-beta activities from 0.006 to 0.89 Bq/l. The highest gross-alpha value was found in the sample taken from near the Kaymaz pluton. The concentrations of (222)Rn varied from 0.060 to 0.557 Bq/l.

Background Radiation↗

PubMed2005

Radioactivity of the Bega sediment-case study of a contaminated canal.

The Bega canal is one among many heavily polluted canals in Vojvodina (the northern province of Serbia and Montenegro). In the framework of the revitalization of this canal, the radionuclide content of the sediment was investigated in order to support the safe deposition after excavation. It was found that, in comparison with the Danube sediment and Vojvodina soil, the Bega sediment is contaminated with (238)U and (137)Cs. The origin of this contamination is discussed. No traces of contamination by nuclear power plants in the region were found, while the presence of technologically enhanced, natural occurring radioactive materials (TENORM) was proved.

Background Radiation↗

PubMed2004

Assessment of natural and anthropogenic radioactivity levels in rocks and soils in the environs of Swieradow Zdroj in Sudetes, Poland, by in situ gamma-ray spectrometry.

The natural radioactivity of 40K, 208Ti, 212Pb, 214Pb, 228Ac, and the fallout of 137Cs in typical rocks and soils of Swieradów Zdrój area (Sudetes Mountains, Poland) were measured in situ using a portable gamma-ray spectrometry workstation. The measurement points were chosen for different regional lithology: within hornfelses of the Szklarska Poreba schist-belt, quartz rocks, gneisses of the Swieradów Zdrój unit, leucogranites, leptinites, mica schists of the Stara Kamienica belt, and finally the zones of the southern and northern contacts of the Stara Kamienica schist-belt with leucogranites and gneisses of the Lesna unit, respectively. 40K activity varied in the range from about 320 Bq kg(-1) (quartz) to 1200 Bq kg(-1) (gneisses). The activity concentrations associated with 228Ac (232Th series) varied in the range from 25 Bq kg(-1) (quartz) to 62 Bq kg(-1) (leucogranites), whereas activity concentration of 226Ra varied in the range from about 31 Bq kg(-1) (hornfelses) to 122 Bq kg(-1) (leucogranites). Relatively low deposits of 137Cs were noted in the investigated area, where the activity concentrations ranged from 4001 (hornfelses) Bq m(-2) to less than 154 Bq m(-2) (leucogranites).

Cesium Radioisotopes↗

PubMed2004

Natural radioactivity and radiation exposure in the high background area at Chhatrapur beach placer deposit of Orissa, India.

A high natural background radiation area is reported for the Chhatrapur beach placer deposit of Orissa state, on the southeastern coast of India, due to the presence of radiogenic heavy minerals. The average activity concentrations of radioactive elements 232Th, 238U and 40K were measured by gamma-ray spectrometry using a HPGe detector, and found to be 2500 +/-1850, 230 +/- 140 and 120 +/- 35 Bq kg-1, respectively, for the bulk sand samples. The absorbed gamma dose rates in air due to the naturally occurring radionuclides varied from 375 to 5000 nGy h-1, with an average value of 1625 +/- 1200 nGy h-1. The external annual effective dose rate of the region ranged from 0.46 to 6.12 mSv y-1, with an average value of 1625 +/- 1200 mSv y-1. The absorbed gamma dose rate levels of Chhatrapur beach area were similar to the monazite sand-bearing high background radiation areas of southern and southwestern coastal tracts of India and other similar areas of the world. The major contributors to the enhanced level of radiation are monazite and zircon sands.

Environmental Exposure↗

PubMed2005

Preparedness of households and catering establishments for incidents involving radioactive contamination.

This short paper describes a number of investigations carried out to ensure preparedness for crises involving radioactivity to catering operations and private households in Finland. The specific recommendations for catering kitchens during crises were published in 1994. A study to determine the level of adherence to these recommendations is summarised here, together with its findings and subsequent recommendations. Another study on the pre-planning of crisis menus is described. New challenges for the catering kitchens are touched upon. A crisis food preparation booklet for households is described and based on consumers' attitudes suggestions are made for how this can be improved in the future.

Cities↗

PubMed2005

The logistics of food supply following radioactive fallout.

Discussions at the national level about critical infrastructure and its vulnerability are more common now following the events of September 11. The National Emergency Supply Agency organised a training exercise to test the logistics of food supply following passage of a plume containing radioactive material over a district in Finland. This short paper summarises the problems that had to be faced and suggests a way forward for improving emergency preparedness in this area.

Animals↗

PubMed2006

Patterns and inventories of radioactive contamination of island sites of the Yenisey River, Russia.

The distribution of radioactive contamination at three island sites downstream from the Krasnoyarsk Mining and Chemical Combine (KMCC) was studied with the objectives of mapping contamination levels, interpreting radionuclide distributions through consideration of alluvial processes and determining radionuclide inventories. Contamination was measured using in situ gamma spectrometry and landforms characterised using topographic surveying methods. Maximum (137)Cs contamination densities (700 kBq m(-2)) were found on low- and middle-level floodplains and low-lying interconnecting areas of Beriozovy Island (16 km from the KMCC). On Mikhin Island (180 km from the KMCC) maximum total (60)Co, (152)Eu and (154)Eu activity concentrations (30-40 kBq m(-2)) occur in low-lying areas inundated during flooding. Maximum (137)Cs and total (60)Co, (152)Eu and (154)Eu contamination densities on Cheriomukhov Island (250 km from the KMCC) were 390 and 50 kBq m(-2), respectively. Estimated (137)Cs inventories were 145, 148 and 16GBq for Beriozovy, Mikhin and Cheriomukhov Islands, respectively.

Cesium Radioisotopes↗

PubMed2005

Bio-monitoring the genotoxicity of populations of Scots pine in the vicinity of a radioactive waste storage facility.

Results of a long-term (1997-2002) study of the Scots pine populations growing in the vicinity of the radioactive waste storage facility ('Radon' LWPE) are presented. Cytogenetic disturbances in reproductive (seeds) and vegetative (needles) tissues sampled from Scots pine populations were studied to examine whether Scots pine trees have experienced environmental stress in areas with relatively low levels of pollution. The data clearly indicate the presence of mutagenic contaminants in the environment of the pine trees. An increased number of mitotic abnormalities, especially multipolar mitoses was found in the pine tree populations submitted to man-made exposure, which suggests that the cytogenetic damage is mainly caused by chemical contamination. A higher radioresistance of the Scots pine seeds from the impacted populations was shown by use of acute gamma-irradiation. During the observation period 1997-2002, pine trees exposed to anthropogenic pollution showed a steady increase of cytogenetic alterations in the root meristem cells.

Cytogenetics↗

PubMed2005

Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia in relation to sedimentation processes and geomorphology.

The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137Cs floodplain inventory of 33.7 GBq.

Cesium Radioisotopes↗

PubMed1997

Sorption/desorption of radioactive contaminants by sediment from the Kara Sea.

To understand the long term impact of the disposal of radioactive waste on the Kara Sea, partition coefficients (Kd) for several important radionuclides, the mineralogy of the sediment, and the relationship of Kd to liquid-to-solid ratio were quantified. Sediment was obtained from four locations in the Kara Sea area. Slow sorption kinetics were observed for 85Sr, 232U, 125I and 99Tc, whilst sorption was rapid (less than 50 h to steady-state) for 137Cs, 210Pb, and 241Am. Partition coefficients (Kd) were determined using batch type experiments and sorption isotherms which were developed for 85Sr, 99Tc, 125I, U and 137Cs. Partition coefficients for 137Cs were approx. 350 ml/g for sediment from the Trough and 180 ml/g for Stepovogo Fjord. This difference may be caused by the lower fraction of expandable clay in sediment from the fjord. Uptake of 85Sr, 99Tc, 125I, and U were all similar for both locations, with Kd values averaging 4, 3, 17 and 60 ml/g, respectively. The Kd for 137 Cs varied non-linearly from 40 to 3800 ml/g as the liquid-to-solid ratio varied from 3.4 to 6500, but only when the sorption capacity was high compared to the mass of 137Cs in the closed system of the experiment. Under identical conditions, sediment with lower Kd values showed no effect. Oxidation of sediment effectively desorbed 99Tc from the solid phase, whilst it caused increased uptake of 85Sr and U. In sequential rinses with fresh seawater, desorption was limited to 60% of 137Cs and 85Sr, and 35% of uranium.

Absorption↗

PubMed1998

Accumulation of 210Pb, 226Ra and radioactive cesium by fungi.

Fungi sampled in three areas in France were analyzed by gamma-spectrometry for their concentrations of 134Cs, 137Cs, 210Pb and 226Ra. In most of the samples radioactive cesium was detected with a maximum of 2860 Bq kg-1 (dry wt.). Activity concentrations of 210Pb were in the range < 1.76-36.5 Bq kg-1 (dry wt.). Activity concentrations of 226Ra were consistently lower, often by one order of magnitude. Models are developed to estimate the contributions of atmospheric 210Pb deposited onto the fruit bodies to the measured 210Pb concentrations and of the uptake of 222Rn soluted in soil pore water which subsequently decays into 210Pb. It is shown that both pathways are of only minor importance. Comparison with the soil-mushroom concentration ratios of stable lead, which were determined for some of the samples, confirmed that 210Pb in mushrooms mainly originates from direct uptake of 210Pb present in the soil. Despite of the high concentrations of 137Cs detected in most of the mushrooms, radiation doses to individuals due to mushroom consumption are dominated by 210Pb for the majority of the edible mushrooms sampled.

Agaricales↗

PubMed1999

Marine radioactivity assessment of Mururoa and Fangataufa atolls.

The International Atomic Energy Agency (IAEA) carried out an international project. 'The Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa' with the aim of assessing the present and future radiological situation at the atolls and making recommendations for either monitoring or remedial actions if they are deemed necessary. The paper concentrates on marine radioactivity aspects and gives an estimation of present radionuclide concentrations in water, sediment and biota of the Mururoa and Fangataufa lagoons and the surrounding ocean. The dominant radionuclide in both lagoons is Pu in sediments (the total inventory is approximately 30 TBq). A decline in radionuclide concentrations has been observed in recent years in lagoon water, with the exception of 3H and 90Sr, for which a contribution from underground sources is to be expected. Radionuclide concentrations in biota from the lagoons and the surrounding ocean are low and consistent with previous measurements. The observed radionuclide concentrations in both lagoons imply that no radiological risk exists for hypothetical inhabitants of Mururoa and Fangataufa Atolls.

Animals↗

PubMed2001

Coloured rain dust from Sahara Desert is still radioactive.

A coloured rain event originating from the Sahara Desert occurred on April 9, 2000 at Thessaloniki, Northern Greece (40 degrees 38'N, 22 degrees 58'E). The radioactive nuclides that were determined in a coloured rain dust sample were 137Cs of Chernobyl origin, 7Be of cosmogenic origin and 40K of terrestrial origin. Cesium-137 still remained 14 years after the Chernobyl accident, reaching 26.6 Bq kg-1 in the coloured rain dust.

Africa, Northern↗

PubMed2001

Evaluation and ranking of restoration strategies for radioactively contaminated sites.

An international project, whose aim was the development of a transparent and robust method for evaluating and ranking restoration strategies for radioactively contaminated sites (RESTRAT), was carried out under the Fourth Framework of the Nuclear Fission Safety Programme of the EU. The evaluation and ranking procedure used was based on the principles of justification and optimisation for radiation protection. A multi-attribute utility analysis was applied to allow for the inclusion of radiological health effects, economic costs and social factors. Values of these attributes were converted into utility values by applying linear utility functions and weighting factors, derived from scaling constants and expert judgement. The uncertainties and variabilities associated with these utility functions and weighting factors were dealt with by a probabilistic approach which utilised a Latin Hypercube Sampling technique. Potentially relevant restoration techniques were identified and their characteristics determined through a literature review. The methodology developed by this project has been illustrated by application to representative examples of different categories of contaminated sites; a waste disposal site, a uranium tailing site and a contaminated freshwater river.

Costs and Cost Analysis↗

PubMed2004

Continuous radioactivity monitoring systems. From the pre-history of radioprotection to the future of radioecology.

The first significant quantities of artificial radioactivity appeared in the environment around the end of the 1940s. They were gigantic and their metrology very quickly seemed to be essential for sanitary and military reasons. In the 1950s, the first continuous monitoring systems of "fall out" were created. They were neither automatic nor sensitive and radioprotection of the environment was not a concern only for simple public information. Since then, radioecology, technology and evolution of our mentality have completely modified our way of thinking. Thus, from the 1980s up to the dawn of the new millennium, the gap between the performances of metrology laboratories and certain aspects of direct measurement has almost disappeared. 1986 certainly contributed a lot to the concept of surveillance networks and alarm systems, emphasising that the major advantage of these is the fact that they are operational, the minute before the accident.

Environmental Monitoring↗