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This paper investigates the concentration of natural and anthropogenic radioactivity in 38 different milk samples locally and imported have gathered from locally markets and dairy farmhouses in Baghdad city. They had been investigated through high-purity germanium (HPGe) detector gamma spectrometer with huge resolution (2.0 keV at 1332 keV) as well as relative efficiency of ~30% for 137Cs (661.7 keV). Based on the gotten data, the activity concentrations (Bq/kg or Bq/L) intended for 40K, 137Cs, 214Bi (238U series) and 228Ac (232Th series) in imported full milk powder, baby milk/1, baby milk/ 2 along with raw cow's milk (liquid) locally and imported testers had measured. These investigated values are within the international standards regarding radioactivity in foodstuff. A mean magnitude of radium equivalent activity (Raeq) in each milk sample has been under a threshold magnitude of 370 Bq/kg or Bq/L. Each value regarding indoor and outdoor annual effective dose corresponding to milk testers has been less than the international typical magnitudes (0.45 mSv/y concerning indoor as well as 0.07 mSv/y regarding outdoor) [ABSTRACT FROM AUTHOR]

The majority of the area contaminated by the Fukushima Daiichi Nuclear Power Plant accident is covered with forests. We developed a dataset for radiocaesium (137Cs) in trees, soil, and mushrooms measured at numerous forest sites. The 137Cs activity concentration and inventory data reported in scientific journal papers written in English and Japanese, governmental reports, and governmental monitoring data on the web were collated. The ancillary information describing the forest stands were also collated, and further environmental information (e.g. climate) was derived from the other databases using longitude and latitude coordinates of the sampling locations. The database contains 8593, 4105, and 3189 entries of activity concentration data for trees, soil, and mushrooms, and 471 and 3521 entries of inventory data for trees and soil, respectively, which were collected from 2011 to 2017, and covers the entire Fukushima prefecture. The data can be used to document and understand the spatio-temporal dynamics of radiocaesium in the affected region and to aid the development and validation of models of radiocaesium dynamics in contaminated forests. Measurement(s) activity (of a radionuclide) • Cesium Cs 137 Technology Type(s) digital curation Factor Type(s) geographic location Sample Characteristic - Organism Cryptomeria japonica • Chamaecyparis obtusa • Pinus densiflora • Quercus serrata Sample Characteristic - Environment temperate evergreen needleleaf forest • temperate deciduous broadleaf forest • leaf • wood • litter layer • forest soil • mushroom (food source) • bark • pollen Sample Characteristic - Location Japan • Fukushima Prefecture Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.13166462 [ABSTRACT FROM AUTHOR]

Abstract There is widespread degradation of the environment of the Niger Delta region of Nigeria such that the United Nations Environment Program described it as an ecological wasteland. The contamination is due mainly to unregulated oil and gas production activities leading to oil spills and illegal disposal of contaminated materials, indiscriminate industrial and domestic discharges into water bodies. This widespread contamination includes naturally occurring radioactive materials (NORM) and technologically enhanced radioactive materials (TENORM). NORMs are naturally associated with every mineral in the earth crust, thus the exploitation of such minerals may transport NORM to the surface as TENORM. If uncontrolled by operators and unregulated by government agencies, NORM can find its way into surface and ground water, seafood and even crops consumed by humans. The Niger Delta region is the hub of oil and gas activities providing huge employment and socioeconomic benefits to its indigenes and accounting for more than 90% of foreign exchange earnings for the country. However, uncontrolled spills and discharges from these activities have left the land desolate, degrading most of its aquifers and surface waters, leaving the indigenes with a Hobson choice, eating and drinking contaminated substances everyday of their lives. It is expedient that attention be drawn to this area as radionuclides such as Po-210, Pb-210 and Ra-226 have been confirmed as radiotoxic and may be responsible for several new cases of health challenges reported in the study area over the years. Highlights • Oil and Gas activities utilise and discharge waste into the environment containing radionuclides. • Drilling and production activities are capable of bring NORM to the surface and injecting same into food chain. • The Niger Delta is the oil and gas hub of Nigeria with reported ecologic devastation since oil discovery. • Many authors have reported radioactivity in several media in the Niger Delta to be higher than stipulated limits. • Environmental radioactivity is a recent science in Nigeria. Scientists should make efforts to provide data for policymakers to enforce regulations on discharges from oil and gas activities. • More research needs to be supported for continuous monitoring of the occurrence of radionuclides in the region under review. [ABSTRACT FROM AUTHOR]

Abstract Environmental hazards are caused by uranium mining legacies and enhanced radioactivity in utilized groundwater and surface water resources. Knowledge of uranium speciation in these waters is essential for predicting radionuclide migration and for installing effective water purification technology. The validity of the thermodynamic data for the environmental media affected by uranium mining legacies is of utmost importance. Therefore, a comprehensive and consistent database was established according to current knowledge. The uranium data included in the database is based on the NEA TDB (Guillaumont et al., 2003) and is modified or supplemented as necessary e.g. for calcium and magnesium uranyl carbonates. The specific ion interaction theory (Brönsted, 1922) is used to estimate activity constants, which is sufficient for the considered low ionic strengths. The success of this approach was evaluated by comparative experimental investigations and model calculations (PHREEQC (Parkhurst and Appelo, 1999)) for several model systems. The waters differ in pH (2.7–9.8), uranium concentration (10−9-10−4 mol/L) and ionic strength (0.002–0.2 mol/L). We used chemical extraction experiments, ESI-Orbitrap-MS and time-resolved laser-induced fluorescence spectroscopy (TRLFS) to measure the uranium speciation. The latter method is nonintrusive and therefore does not change the chemical composition of the investigated waters. This is very important, because any change of the system under study may also change the speciation. Highlights • Chemical modelling of uranium-rich natural groundwaters. • Comparing selected thermodynamic parameters with experimental deduced speciation. • Capabilities & limitations of advanced analytical techniques to quantify speciation. [ABSTRACT FROM AUTHOR]

Abstract The present work deals with assessment of baseline radionuclide concentration in marine organisms around selected coasts of Maharashtra, India. This baseline study highlights concentrations of natural and fallout radionuclides in finfish and shellfish species found in the surrounding seawater. Water and fish samples were collected, processed, and analyzed for 238U, 226Ra, 228Ra, 232Th, 40K, and 137Cs by high-resolution gamma spectrometry. 238U, 226Ra, 228Ra, 232Th, 40K, and 137Cs concentrations were found to be in the range of ≤1.5, ≤2.0, ≤0.4, ≤1.5, ≤8.0 to 258, and ≤0.2 Bq/kg, respectively. The seasonal study revealed the maximum concentration in premonsoon season. Activity concentrations were higher in pelagic fish than those in demersal fish. A higher concentration factor was reported in shellfish than in finfish. Highlights • Present work is first documentation on baseline radioactivity (natural and artificial) conducted around a proposed nuclear power plant along southwest konkan region for nuclear energy in future. • The results for all naturally occurring radionuclides were BDL except for K-40. • The concentration of 40K was found to be in the range of ≤8.0 to 258 Bq/kg. • Seasonal variation revealed maximum concentration in pre-monsoon compared to post-monsoon. • Maximum activity concentrations were found in pelagic fishes compared to demersal fishes. [ABSTRACT FROM AUTHOR]

We report temporal variations of 137 Cs activity concentrations in surface waters of six regions of the western and central North Pacific Ocean during 2011–2017 using a combination of 1264 previously published data and 42 new data. In the western and central North Pacific Ocean at latitudes of 30–42°N and longitudes of 140°E to 160°W, eastward transport of radiocaesium was clearly apparent. 137 Cs activity concentrations in surface water decreased rapidly to ∼2–3 Bq m −3 in 2015/2016, still a bit higher than 137 Cs activity concentrations before the FNPP1 accident (1.5–2 Bq m −3 ). 134 Cs/ 137 Cs activity ratios decay-corrected to 11 March 2011 were ∼0.5–0.8. To the south of 30°N and between 130°E and 160°W in the western and central Pacific Ocean, 137 Cs activity concentrations were around 1–7 Bq m −3 in 2011/2012 but then stabilized at a few Bq m −3 up to 2017. 134 Cs activity concentrations were detected at levels of 0.1–0.9 Bq m −3 , and 134 Cs/ 137 Cs activity ratios decay-corrected to 11 March 2011 were ∼0.3–0.5. Temporal variations of model-simulated 137 Cs activity concentrations in surface water in the region of interest showed good agreement with observations, except in the southwestern North Pacific Ocean. [ABSTRACT FROM AUTHOR]

Radioactivity and heavy metal toxicity of multi-metal deposits coexisting with the element uranium (U) could have long-term adverse impacts on soil biological processes and the health of soil ecosystems. Soil enzyme activities are considered bioindicators for assessing soil health. An experiment was designed to investigate invertase and β-glucosidase activity in multi-metal deposits. Radioactivity and heavy metals were also investigated during this study. Our results showed that the invertase and β-glucosidase activities were significantly lower in the core mining area than the control area (p<0.05). Activities of the two enzymes decreased with increasing metal concentrations and radioactivity. Cu and Zn showed significant negative effects on β-glucosidase and invertase activities in a multi-metal deposit at the study site. A significant nonlinear relationship was recorded between soil enzyme activities, radiation dose (R2 = 0.71, 0.63; p<0.05), Zn (R2 = 0.34, 0.41; p<0.05) and Cu concentrations (R2 = 0.46, 0.45; p<0.05). There were turning points at 1 μGy h-1, 250 μg g-1, and 30 μg g-1 for radiation dose, Zn and Cu contents, respectively. The findings could provide more information regarding the toxic effects of radiation and heavy metals on the soil health of multi-metal deposits, which can more precisely guide environmental protection. [ABSTRACT FROM AUTHOR]

The present study was undertaken as a survey of radiological and chemical air pollution on both the European and Asian sides of Istanbul, Turkey. In this framework, radionuclide activity concentrations and selected metal amounts in moss samples collected from urban, suburban, industrial, and green zone areas in Istanbul were determined following the moss biomonitoring technique. The activity concentrations in the moss samples vary from 2 to 20 Bq/kg for 226Ra, from 4 to 23 Bq/kg for 232Th, and 359 to 2,809 Bq/kg for 40 K for both sides of the city. Concentrations of Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Sb, V, and Zn were determined by ICP-ES. Additionally, potential ecological impacts of atmospheric deposition for selected metals based on moss analysis around Istanbul were assessed. Results show that the enrichment factor for the European side was greater than 10 for Pb. [ABSTRACT FROM AUTHOR]

A set of measurements have been conducted to determine the levels activity of gamma-emitters present in infant formula. The study of different samples shows the presence of the following radionuclides: 226Ra, 232Th and 40K with respectively average activity of 0.52 ±  0.087, 0.51 ± 0.062, 371.98  ± 3.68 Bq/kg. The mean annual doses lead to 0.62 and 0.24 mSv/year whereas the total risk is about 7.91 × 10−6 and 5.32 × 10−6 respectively ≤ 1 year and 1–2 years old infants. The obtained results show that no significant radiation dose and no risk to the infants due to consumption of these milks. [ABSTRACT FROM AUTHOR]

Batch sorption and column experiments were conducted to investigate and compare sorption and transport behavior of 90Sr on the assumption of seawater intrusion at nuclear power plants. Batch sorption experiments were carried out on fractured rocks and bedrocks using synthetic groundwater and seawater both spiked with 90Sr. In general, higher 90Sr sorption occurred on fractured rock samples than on bedrocks, because of the presence of weathered secondary minerals (iron oxide and clay) on fractured rock surfaces. However, one particular bedrock sample (WSP-B) which has higher porosity and carbon amount than fractured rock samples also showed the higher 90Sr sorption than its comparable fractured rocks. For all batch sorption studies, 90Sr sorption distribution coefficient, Kd decreased from groundwater to seawater environment due to the higher ionic strength of seawater (6.4 × 10-1-7.7 × 10-1 M) compared to groundwater (4.0 × 10-3-6.0 × 10-3 M). The three different ionic strength solutions were used in column experiments, and the results showed that transport behavior of Sr through a fractured rock had similar sorption trend to batch sorption results. The highest mobility (or least retardation) for Sr was found for 100 % seawater solution compared to the highest retardation (or least mobility) for 100 % groundwater solution. These sorption and transport data of Sr on solid materials contacted with various ionic strength solutions corroborate empirically defensible information for assessment of radioactive contamination in groundwater below the NPP sites located nearby shores. In addition, the experimental data will be incorporated to improve transport models of 90Sr in the subsurface environment for severe nuclear accidents. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the activity concentrations of natural terrestrial radionuclides ( 238 U, 226 Ra, 232 Th and 40 K) and airborne radionuclides ( 210 Pb, 210 Pb ex and 7 Be) in natural terrestrial mosses. The collected moss samples (46) representing 17 species were collected from 17 sampling localities in the National Parks and Wildlife Sanctuaries of Thailand, situated in the mountainous areas between the northern and the southern ends of peninsular Thailand (∼7–12 °N, 99–102 °E). Activity concentrations of radionuclides in the samples were measured using a low background gamma spectrometer. The results revealed non-uniform spatial distributions of all the radionuclides in the study area. Principal component analysis and cluster analysis revealed two distinct origins for the studied radionuclides, and furthermore, the Pearson correlations were strong within 226 Ra, 232 Th, 238 U and 40 K as well as within 210 Pb and 210 Pb ex , but there was no significant correlation between these two groups. Also 7 Be was uncorrelated to the others, as expected due to different origins of the airborne and terrestrial radionuclides. The radionuclide activities of moss samples varied by moss species, topography, geology, and meteorology of each sampling area. The observed abnormally high concentrations of some radionuclides probably indicate that the concentrations of airborne and terrestrial radionuclides in moss samples were directly related to local geological features of the sampling site, or that high levels of 7 Be were most probably linked with topography and regional NE monsoonal winds from mainland China. [ABSTRACT FROM AUTHOR]

A method for fast determination of the activity in soil samples by measuring a fresh soil core sample from both ends with an HPGe-detector is proposed. The method was tested by simulations, as well as by measurements on spiked soil samples. Both simulations and measurements showed that the geometrical mean of the count rates when the sample is measured twice, with the bottom and the top end, respectively, facing the detector closely resembles the count rate from a measurement on a homogenized sample. Therefore, an efficiency calibration for homogenized samples could be used even if the activity is highly inhomogeneous in the soil core, as is the case with fresh fallout. It was also shown that by studying the ratio between the two measurements, a rough estimation of the extent of penetration of the radionuclide in the soil can be found. This will enhance the possibility to make rapid estimations of the soil inventory by field gamma spectrometry. [ABSTRACT FROM AUTHOR]

In response to the accident at Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP), vehicle-borne monitoring was used to map radiation levels for radiological protection of the public. By convention measurements from vehicle-borne surveys are converted to the ambient dose equivalent rate at 1 m height in the absence of the vehicle. This allows for comparison with results from other types of survey, including surveys with hand-held or airborne instruments. To improve the accuracy of the converted results from vehicle-borne surveys, we investigated combining measurements from two detectors mounted on the vehicle at different heights above the ground. A dual-detector setup was added to a JAEA monitoring car and compared against hand-held survey meter measurements in Fukushima Prefecture. The results obtained by combining measurements from two detectors were within ±20% of the hand-held reference measurements. The mean absolute percentage deviation from the reference measurements was 7.2%. The combined results from the two detectors were more accurate than those from either the roof-mounted detector, or the detector inside the vehicle, taken alone. One issue with vehicle-borne surveys is that ambient dose equivalent rates above roads are not necessarily representative of adjacent areas. This is because radiocesium is often deficient on asphalt surfaces, as it is easily scrubbed off by rain, wind and vehicle tires. To tackle this issue, we investigated mounting heights for vehicle-borne detectors using Monte Carlo gamma-ray simulations. When radiocesium is deficient on a road compared to the adjacent land, mounting detectors high on vehicles yields results closer to the values adjacent to the road. The ratio of ambient dose equivalent rates reported by detectors mounted at different heights in a dual-detector setup indicates whether radiocesium is deficient on the road compared to the adjacent land. [ABSTRACT FROM AUTHOR]

A laboratory study of the formation of the primary vertical profile of the 137 Cs activity concentration in the anaerobic organic matter-rich sediments was carried out. The incubation was performed using sediment baths method (initial thickness of the water layer over the sediments ∼40 cm, initial radiocesium activity concentration in water ∼14.53 Bq·L −1 ). An exponential profile (R 2 ∼0.999) with the half-height width of ∼0.65 cm was formed after ∼32 days of the incubation. A further course of the experiment (sediments were sampled after 64, 130 and 293 days of the incubation) revealed deviations in the form of the radiocesium activity concentration profile related to the appearance of the additional Gauss factor with the increasing half-height width of ∼1.2, ∼1.3 and ∼3 cm, respectively. In spite of the evident growth of the half-height width, the radiocesium migration rate decreased from 0.02 cm·day −1 for the first 32 days of incubation down to 0.009 cm·day −1 at the end of the incubation experiment. Such a time-dependent decrease in the radiocesium migration is possibly related to the beginning of the second radiocesium migration phase depending on the retardation factor. Besides diffusion, the formation of vertical profiles of radiocesium activity concentrations in sediments was additionally induced by effects of buoyancy of the upper sediment layer due to the seepage of the above lying water into sediments. [ABSTRACT FROM AUTHOR]

The large inventory of radioactivity released during the March, 2011 Fukushima Dai-ichi nuclear reactor accident in Japan spread rapidly across the North Pacific Ocean and was first observed at the westernmost station on Line P, an oceanographic sampling line extending 1500 km westward of British Columbia (BC), Canada in June 2012. Here, time series measurements of 134Cs and 137Cs in seawater on Line P and on the CLIVAR-P16N 152°W line reveal the recent transport history of the Fukushima radioactivity tracer plume through the northeast Pacific Ocean. During 2013 and 2014 the Fukushima plume spread onto the Canadian continental shelf and by 2015 and early 2016 it reached 137Cs values of 6-8 Bq/m3 in surface water along Line P. Ocean circulation model simulations that are consistent with the time series measurements of Fukushima 137Cs indicate that the 2015-2016 results represent maximum tracer levels on Line P and that they will begin to decline in 2017-2018. The current elevated Fukushima 137Cs levels in seawater in the eastern North Pacific are equivalent to fallout background levels of 137Cs that prevailed during the 1970s and do not represent a radiological threat to human health or the environment. [ABSTRACT FROM AUTHOR]

The objective of this paper is to develop a dose assessment method that takes into account the working postures and the non-uniformity of the radiation fields to ensure the radiation safety of workers in nuclear facilities. To simulate different working postures, the working posture models were developed with skeletal animation technology. And to assess the exposure dose to workers in a non-uniform radiation field, virtual reality technology was used to develop a model of a hypothetical human with organ-monitoring-points distributed in his/her organs and tissues. And then a dose assessment method based on skeletal animation technology and the organ-monitoring-points was developed. Simulation results were compared with that of MCNP, the point model and the organ’s minimum bounding box model, and they show that the method is effective in providing dose assessments to workers, taking into consideration the working postures and non-uniformity of radiation environments. [ABSTRACT FROM AUTHOR]

Aerial gamma ray surveys are an important tool for national security, scientific, and industrial interests in determining locations of both anthropogenic and natural sources of radioactivity. There is a relationship between radioactivity and geology and in the past this relationship has been used to predict geology from an aerial survey. The purpose of this project is to develop a method to predict the radiologic exposure rate of the geologic materials by creating a high resolution background model. The intention is for this method to be used in an emergency response scenario where the background radiation environment is unknown. Two study areas in Southern Nevada have been modeled using geologic data, images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data, and pre-existing low resolution aerial surveys from the National Uranium Resource Evaluation (NURE) Survey. Using these data, geospatial areas that are homogenous in terms of K, U, and Th, referred to as background radiation units, are defined and the gamma ray exposure rate is predicted. The prediction is compared to data collected via detailed aerial survey by the Department of Energy's Remote Sensing Lab - Nellis, allowing for the refinement of the technique. By using geologic units to define radiation background units of exposed bedrock and ASTER visualizations to subdivide and define radiation background units within alluvium, successful models have been produced for Government Wash, north of Lake Mead, and for the western shore of Lake Mohave, east of Searchlight, NV. [ABSTRACT FROM AUTHOR]

The mountain's composition, especially the granitic mountains, contains a certain amount of natural radioactivity due to the decay of uranium, thorium, and potassium isotopes. As a part of the impact assessment study, thirty rock samples were collected from natural mountains in the Red Sea coast, Egypt, considered as the most popular ones, and were measured for their natural radioactivity to assess the radiological impact when they are used as building materials. Rock samples were examined by high-resolution γ-spectrometry. The average activity concentration of 238U, 226Ra, 232Th, and 40K were 192 ± 24, 178 ± 27, 66 ± 7 and 193 ± 23, and 287 ± 31 Bq/kg, respectively. The annual effective dose rate (mSv/y), the mean of the absorbed dose rates (D), radium equivalent (Raeq), the external hazard index (Hex) and the internal hazard index (Hin) and the representative level index (Iγr, Iαr) were; 0.25 mSv/y, 205.64 nGy/h, 286.9 Bq/kg, 0.81, 1.33, 1.97 and 0.89, respectively. The specific activity ratios of 226Ra/238U and 232Th/238U were evaluated to analyze the behavior of these radionuclides. [ABSTRACT FROM AUTHOR]

The concentrations of 137 Cs in the air, which were divided into coarse (>1.1 μm ϕ) and fine (<1.1 μm ϕ) fractions of particulate matter (PM), were measured from October 2012 to December 2014 in an area evacuated after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Total atmospheric 137 Cs concentrations showed a clear seasonal variation, with high concentrations during summer and autumn related to the dominant easterly wind blowing from the highly radioactivity contaminated area. This seasonal peak was dominated by 137 Cs in the coarse PM fraction. The 137 Cs specific activity (massic 137 Cs concentration) in the coarse PM was also found to increase significantly in summer, whereas that in the fine PM showed no variability during the year. These results show that coarse and fine 137 Cs-bearing PM have different origins and behaviors in the resuspension process. The seasonal variation in atmospheric 137 Cs concentration was well correlated with the mean 137 Cs surface contamination (deposition density) around the observation site weighted by the frequency of wind direction, indicating that the atmospheric 137 Cs concentration in the observation site was explained by the distribution of the 137 Cs surface contamination and the frequency of different wind directions. We introduced a resuspension factor corrected for wind direction, consisting of the ratio of the atmospheric 137 Cs concentration to the weighted mean 137 Cs surface contamination, which evaluated the intensity of resuspension better than the conventional resuspension factor. This ratio ranged from 5.7 × 10 −11 to 8.6 × 10 −10 m −1 and gradually decreased during the study period. [ABSTRACT FROM AUTHOR]

To improve the pretreatment efficiency of radiocesium in seawater, a prototype machine based on a new design of an integrated device for coprecipitation and filtration was developed and tested in the laboratory for its possibility and efficiency, the results show the that the efficiency of pretreatment of radiocesium can be improved more than one orders of magnitude compared to traditional methods. And the results from experiments on effect of settle time show that immediately filtration of solution after reaction will not affect the absorption of AMP to radiocesium in seawater. [ABSTRACT FROM AUTHOR]

Environmental contamination with radioactive materials of geogenic and anthropogenic origin is a global problem. A variety of mutagenicity test procedures has been developed which enable the detection of DNA damage caused by ionizing radiation which plays a key role in the adverse effects caused by radioisotopes. In the present study, we investigated the usefulness of the Tradescantia micronucleus test (the most widely used plant based genotoxicity bioassay) for the detection of genetic damage caused by environmental samples and a human artifact (ceramic plate) which contained radioactive elements. We compared the results obtained with different exposure protocols and found that direct exposure of the inflorescences is more sensitive and that the number of micronuclei can be further increased under “wet” conditions. The lowest dose rate which caused a significant effect was 1.2 μGy/h (10 h). Comparisons with the results obtained with other systems (i.e. with mitotic cells of higher plants, molluscs, insects, fish and human lymphocytes) show that the Tradescantia MN assay is one to three orders of magnitude more sensitive as other models, which are currently available. Taken together, our findings indicate that this method is due to its high sensitivity a unique tool, which can be used for environmental biomonitoring in radiation polluted areas. [ABSTRACT FROM AUTHOR]

An environmental radioactivity survey carried out in the Sabugal region, Portugal, showed enhanced radioactivity levels in surface water streams related to water discharges from old uranium mines. Water from irrigation wells in this region displayed variable radionuclide levels due to natural occurrence of radionuclides and to contamination by mine water drainage. Horticulture products grown near the uranium mine sites contained elevated radium (Ra) concentrations, but lower concentrations of uranium and other radionuclides. Despite the relatively high radioactivity in irrigation water, the absorption and accumulation of radionuclides in agriculture products were limited. Nevertheless, taking into consideration the volume of uranium waste piles, it is considered as necessary to improving the management of mine wastes and mine drainage to prevent further increase of environmental radioactivity in the area. The assessment of environmental impact and radiation issues lasting from the past uranium mining shall be used as lessons to improving future mining activities. [ABSTRACT FROM AUTHOR]

A survey was conducted to measure natural radioactivity in spa waters from the Kłodzko Valley. The main goal of this study was to determine the activity concentration of uranium, radium and radon isotopes in the investigated groundwaters. Samples were collected several times from 35 water intakes from 5 spas and 2 mineral water bottling plants. The authors examined whether the increased gamma radiation background, as well as the elevated values of radium and uranium content in reservoir rocks, have a significant impact on the natural radioactivity of these waters. The second objective of this research was to provide information about geochemistry of U, Ra, Rn radionuclides and the radiological and chemical risks incurred by ingestion of isotopes with drinking water. On the basis of results obtained, it is feasible to assess the health hazard posed by ingestion of natural radioactivity with drinking waters. Moreover, the data yielded by this research may be helpful in the process of verification of the application of these waters in balneotherapy. In addition, annual effective radiation doses resulting from the isotopes consumption were calculated on the basis of the evaluated activity concentrations. In dose assessment for uranium and radium isotopes, the authors provided values for different human age groups. The obtained uranium content in the investigated waters was compared with the currently valid regulations concerning the quality of drinking water. Based on the activity concentrations data, the activity isotopic ratios 234 U/ 238 U, 226 Ra/ 238 U, 222 Rn/ 238 U, 222 Rn/ 226 Ra and the correlations between radionuclides content were then examined. In brief, it may be concluded on the basis of the obtained results that radon solubility is inversely proportional to radium and uranium dissolution in environmental water circulation. The presented study allows conclusions to be drawn on the radionuclide circulation among different environmental biota: from lithosphere through hydrosphere to biosphere. [ABSTRACT FROM AUTHOR]

Three hundreds and six black sand samples have been collected from the beach areas along the northern coast of Egypt, parallel and perpendicular to the shoreline. The mineralogy and chemistry of the economic heavy minerals were studied. The grain size distribution of the studied economic minerals shows a unimodal class that mostly in the very fine sand size. The microscopic investigation indicates that the study area is enriched with six economic heavy minerals. These are ilmenite, magnetite, garnet, zircon, rutile and monazite; in addition to leucoxene, arranged in decreasing order of their abundance. The studied black sands suggest a reserve of 329, 183, 24, 21, 7, 1 and 14 thousand tons of ilmenite, magnetite, garnet, zircon, rutile, monazite and leucoxene, respectively. The spherical magnetite grains are higher in Fe 2 O 3 than those of euhedral shaped grains. Ilmenite grains display sub-rounded to euhedral shapes. The altered ilmenite grains have higher TiO 2 and lower Fe 2 O 3 in comparison with the euhedral fresh ones. Garnet occurs as angular (49%), sub-spherical (45%), spherical (5%) and euhedral grains (1%). Garnet grains containing mineral inclusions represent 10% of their concentrate. The euhedral garnet grains have Al, Fe, Mn, Mg and Ca that arranged in decreasing order of their abundance. The magnetic zircon fraction obtained from their bulk concentrate is particularly rich in colored grains (70%). Their common colors are red and brown with some malacons. The reddish-brown color of zircon may be due to iron oxide stains. Some magnetic zircon grains are enriched in Hf and REEs contents. Rutile grains are sub-to well rounded (70%), and rich in TiO 2 . Monazite is enriched in Ce, La, Nd, Th and U. Detectable inclusions of gold, copper, lead, galena, cinnabar, platinum group elements (PGE S ) and silver are recorded in cassiterite. The radiometric measurements revealed that the black sands of the western zone (4 km 2 ) have high values of specific activity, absorbed and effective doses. This is attributed to the high contents of radioactive monazite and zircon. On the other hand, the black sands in the eastern (3 km 2 ) and middle (3 km 2 ) zones have moderate and low radioactivity values due to their lower contents of radioactive zircon. Therefore, the black sands of the western zone are not recommended for use in building constructions, because the inhabitants will receive relatively high radioactive doses. Similarly, the black sands of the middle and eastern zones are also not suitable for building construction purpose unless the radioactive minerals are removed. [ABSTRACT FROM AUTHOR]

The results of the low-background gamma spectrometric measurements of protected mountain areas (Zacharovanyy Kray, Chorne Bahno, Ihthyological Preserve Rika and Uzhanskij National Natural Park) in the region of Primeval Beech Forests of the Transcarpathia, Ukraine, are presented. The distances between sampling points in a single protected area were in the range of 200-400 m in elevation of 300 m; probes were taken from the surface, from depth 20 cm and more than 50 cm. The proposed sampling scheme allows one to investigate the radionuclide concentration in protected area's soils, their distribution on/near the mountain ridges and migration in depth (0-50 cm). We also investigate the influence the soils' pH on the contents and the migration of nuclides. The obtained data allow us to study the statistical regularities between the sampling points along and down mountain ridges on the base of their radionuclide content. These results are important for evaluating the radon content/distribution and developing standards in the radionuclide content of the soil Carpathian region. [ABSTRACT FROM AUTHOR]

Indoor radon and soil radioactivity levels were determined for Erzincan province in Turkey. Indoor radon concentrations were determined in 89 dwellings using CR-39 passive Solid State Nuclear Track Detectors (SSNTDs) for four seasons. The mean annual 222Rn activity concentration was found to be 119 Bq.m−3. In the winter season, indoor radon concentrations showed the highest values while the lowest values were observed in the summer season. A model was used to predict the number of lung cancer incidences due to inhalation of radon. The findings have indicated that radon is responsible for 13% of lung cancer incidences occurring in the Erzincan province. Since indoor radon concentration correlates with 226Ra content in soil beneath the dwellings, soil samples were collected near the houses where indoor radon measurements were performed in order to seek a correlation. The 226Ra, 232Th, 40K and 137Cs activity concentration values were 52, 26, 649 and 9 Bq.kg−1, respectively. The annual effective dose due to naturally occurring radionuclides was around 82 µSv.y−1 which is higher than the world average value of 70 µSv.y−1. The results of the present study are expected to be a useful baseline data for future studies. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to provide an overview of the experience of the US Environmental Protection Agency (EPA) in cleaning up radioactively contaminated sites. In the USA, EPA regulates the radiological clean-up of uranium mill tailings sites, some Department of Energy legacy sites within the US nuclear weapons complex, and Superfund National Priorities List sites. The approach to site remediation decisions, including the determination of clean-up levels, varies according to the enabling legislation granting EPA these authorities. Past practices that gave rise to many of the existing exposure situations at legacy sites were permissible before the advent of environmental clean-up legislation. The Uranium Mill Tailings Radiation Control Act of 1978 authorised EPA to set applicable radioactivity concentration standards for soil clean-up at inactive uranium mill sites and vicinity properties. For the other categories of sites mentioned above, remediation goals are typically based on not exceeding a target excess cancer risk range established under the Comprehensive Environmental Response, Compensation, and Liability Act (also known as 'Superfund'). EPA's regulations for cleaning up various contaminated sites in existing exposure situations often result in residual doses that are typical of optimised doses in planned exposure situations. Although the clean-up levels selected may differ from those adopted in other countries, recommendations from the International Commission on Radiological Protection are reflected in the exposure assessment methodologies used in their establishment. [ABSTRACT FROM AUTHOR]

It is shown how a generalized evaluation of a large variety of environmental radioactivity measurements, without and with using linear unfolding, can be performed with a single program, UncertRadio (UR). Using a function parser allows deriving numerical partial derivatives for ISO GUM compatible uncertainty propagation. The evaluation within UR is extended to include ISO 11929 decision thresholds and detection limits. Alternatively, propagation of distributions with MC simulation is included. Part I gives an overview considering evaluations without using linear unfolding. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the influence of geological and soil formation on natural gamma ( γ) radiation exposure. The aim of this study also to obtain a baseline data of γ radiation exposure and radioactivity associated with soil in the granitic territory at Western Region of Peninsular Malaysia. From 3727 in situ measurements of γ radiation dose rates, the mean value of dose rate obtained in this study is 204 nGy h with the range of between 17 and 1039 nGy h. The mean value obtained in this study is three times higher than the world average value of 57 nGy h. Based on in situ measurements, the range of annual effective dose received by the population living in the study area is 0.02-1.28 mSv y. The study found that the levels of γ radiation exposures are strongly influenced by the geological and soil types. From the gamma spectrometry analysis, the mean radioactivity levels of Ra, Th and K in soil in western region Peninsular Malaysia are slightly higher and comparable with the places of 'High Natural Background Radiation Areas' (HNBRAs) in the world as reported by UNSCEAR (). The mean value of Ra was 120 Bq kg and ranged from 7 to 554 Bq kg, whilst for Th was 276 Bq kg with a range of 23-1806 Bq kg. These values indicate 3 and 9 times, respectively, higher than the world average values. However, the radium equivalent activity (Ra) obtained in this study (277 Bq kg) is lower than permissible values of 370 Bq kg. The radiological indices of radiation hazards in this study show that the index values are higher than the permissible limit values of 1. The mean value for gamma activity index ( I,) external hazard index ( H), internal hazard index ( H) was 1.89, 1.46 and 1.78, respectively. As well as γ radiation levels, radioactivity levels of Ra, Th and K also were strongly influenced by the geological and soil types. [ABSTRACT FROM AUTHOR]

Variants of a hypothetical accident that includes the occurrence of a spontaneous chain reaction are examined. The pathways and intensity of radionuclide emission from a nuclear submarine into seawater are determined. The Cs accumulation at the time of sinking is determined more accurately. The average and maximum Cs emission for use in predicting the contamination of the marine environment in application to the object under study are determined. [ABSTRACT FROM AUTHOR]

An approach to evaluating the contribution of different sources of technogenic radionuclides to the total activity of emissions on the basis of a simulation model is proposed. The model is verified and the principles of application of the new approach in NPP are determined. The fl ow of radionuclides into surface waters can be determined by modeling their kinetics in the reservoirs of the balance scheme of the NPP. At the control points, the discrepancy between the computed and measured specific activity does not exceed 50 mBq/liter, which is comparable to the determination errors. [ABSTRACT FROM AUTHOR]

The radioactivity levels (Rn and Ra) and physico-chemical properties of geothermal waters from two spas of Bayındır are investigated. Radon and radium measurements were made with collector chamber method. The radon concentrations range from 3.0 to 13.3 Bq/l, whereas the radium varies from 0.35 to 1.71 Bq/l. It has been observed that radon levels increase in winter and decrease in summer. The Rn/Ra ratio was found to range from 4.91 to 30.53. Physico-chemical properties of water samples were also analysed. Water samples have considerably stable total dissolved solids values, slight acidity, low electrical conductivity, and temperature (42-48 °C). [ABSTRACT FROM AUTHOR]

The radioactivity concentration of 238 U, 232 Th, 226 Ra, 40 K, and 137 Cs in soil samples collected in a coastal wetland of the Southern Laizhou Bay, China were measured. Mean activity concentrations were 54.4 ± 11.7, 57.9 ± 9.7, 28.6 ± 4.3, 542 ± 21, and 10.2 ± 2.9 Bq kg −1 dry weight for 238 U, 232 Th, 226 Ra, 40 K and 137 Cs, respectively. Statistical analyses suggested significant correlations between clay content and 40 K as well as 137 Cs. The radium equivalent activity, the absorbed dose rate in the air at 1 m above the ground surface, and the external hazard index were calculated. The result showed that the radioactivity level in the wetland was in normal range. But sites along the river tended to have higher radiological hazard indexes. The vertical distributions of radionuclides in profiles illustrated some phenomena, such as vertical transport of 238 U, disequilibrium between 238 U and 226 Ra, and change in material sources. [ABSTRACT FROM AUTHOR]

The development of metrology of iron-55 in low-level radioactivity in environmental solid matrices was realised for conducting radioecological studies. A protocol was developed based on the adaptation of existing methods for the purification of iron-55 with selective chromatographic resin, which was then measured with liquid scintillation. The loss attached treatment chemical steps were quantified with elemental iron by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The tests were used to define the iron retention capacity of selective chromatographic resin, a key element in chemical treatment, and test sample size needed to reach the detection limit of 30 Bq kg −1 dry. The solid samples were analysed with the developed protocol. The activities obtained from iron-55 were below the detection limit of 30 Bq kg −1 dry. [ABSTRACT FROM AUTHOR]

Following the discovery of high levels of indoor radon in various parts of the world, every environmental protection agency is determined to address the potential radon problem. In India, many research groups are determined to characterize the problem as it might exist in Indian dwellings, where poor ventilation and mud structures are common. Not only radon but also its progeny are radioactive. Being a gas radon can disperse and its progeny can attach to aerosols/dust particles to be transmitted in indoor environments. Radon is the second leading cause of lung cancer in North America and the leading cause of lung cancer for individuals who have never smoked. Due to potential public health implications of exposure to high levels of radon, the characterization of radon problem in India must also be complemented with the development of a program to educate the public regarding radon. This paper is an attempt to provide awareness about the environmental radon, its origin, health concerns, present status of radon concentrations in dwellings of Northern India and some remedial actions for protection from radiation. The estimated indoor radon levels are looked into as recommended by the International Commission on Radiological Protection, 2009. [ABSTRACT FROM AUTHOR]

Environmental monitoring in the context of nuclear-related activities refers to the measurements of ambient gamma dose rates in the environment and radioactivity in air, water, soil etc. Since nuclear power programme in Thailand has not yet been in place, the environment surveillance programme in Thailand currently focuses on establishing ‘baseline’ environmental radiation levels and radioactivity for the purpose of establishing impacts of future possible sources such as nuclear accidents. The objective is to assure assessments concerning radiation safety for the environment and public. At present, Thailand's monitoring programme operates eight fixed monitoring stations installed in various regions of Thailand; four of which have been in operation since late 2010. The ambient gamma dose rate data are routinely collected from those four real-time monitoring stations starting from October 2010 to September 2011 as described in this study. Also, the radiation data from each station are statically analysed. This study found that the dose rate from the stations located in north and north-east of Thailand showed an apparent tendency towards a diurnal pattern. With these routine data, the average exposure dose rate was possible to estimate in Thailand. Additionally, the assessment of the equivalent dose from natural background radiation was estimated. [ABSTRACT FROM AUTHOR]

Highlights: [•] The first comprehensive study regarding radioactivity in Turkish marine environment. [•] Assessment of several radionuclides in mussel Mytilus galloprovincialis. [•] Estimation of possible risks due to 210Po for public health. [•] Using active and passive biomonitoring for determination of radioactivity. [•] Comparing the results with previous studies from Turkey and other countries. [ABSTRACT FROM AUTHOR]

A simple wavelet transformation based pre-processing method is employed to minimize the duration of counting for gamma spectrometric measurements of samples from environmental matrices. Among the various forms of analyzing wavelets, a suitable one is chosen for this purpose. Measurements with 55 different counting durations were subjected to the wavelet based processing and results were compared with long duration counting time measurements of K, Cs, radionuclide from U series (Bi, Pb) and Th series (Ac, Bi, Pb, Tl). It is observed that with a proper choice of the wavelet function a tenfold reduction in counting duration can be achieved with errors <5 %. [ABSTRACT FROM AUTHOR]

The Tejo Estuary is a large water body surrounded by seven municipalities and industries with liquid effluent discharges containing contaminants that reach the estuary. This is the case for man-made radionuclides used in nuclear medicine, present in liquid effluents discharged by medical facilities. Radionuclide measurements in seaweeds, mussels, fish, water and sediments sampled along the North bank of the estuary revealed the presence of131I and99mTc, originating from nuclear medicine facilities in Lisboa. Concentrations reached 90 Bq kg−1(wet weight) of99mTc in fish, and 18 Bq kg−1(wet weight) of131I in mussels, and were even higher in the water. Another anthropogenic source of radionuclides is industrial waste, such as phosphogypsum the by-product of phosphoric acid production stockpiled at the South bank of the estuary. Main radionuclides present in phosphogypsum are226Ra,210Pb,210Po and uranium. Concentrations of226Ra in phosphogypsum are about 1000 Bq kg−1, which is a high value in comparison with226Ra in soils of the Tejo valley, <100 Bq kg−1.226Ra, in particular, is dissolved by rainwater from phosphogypsum stacks and seeps into the estuary. Other potential sources of radioactivity are discharges from naval nuclear powered vessels and merchant ships transporting radioactive materials that berth in the Lisboa harbour. A whole survey of the estuary indicated low concentrations of137Cs in sediments, mostly attributed to radioactive fallout. Since waste discharges are undergoing deep modifications due to enhanced urban waste treatment, but economic activities have changed and the use of radiopharmaceuticals increases, the periodic radioactivity monitoring of the Tejo Estuary is advised and should provide feedback to enhanced waste management. [ABSTRACT FROM AUTHOR]

The U.S. military first sponsored ecological research during World War II to monitor the release of radioactive effluent into waterways from plutonium production. The Atomic Energy Commission later expanded these investigations to include studies of radioactive fallout at the Nevada and Marshall Island test sites, particularly after the Fukutyu Maru (Lucky Dragon) accident in 1954. The public outcry against nuclear testing from this accident, which contaminated nearby inhabited islands with radio-active fallout, resulted in a considerable influx of funding for environmental science at the Atomic Energy Commission. Many biologists who conducted these studies on nuclear fallout and waste for the Atomic Energy Commission began to develop concerns about radioactive pollution in the environment from the long-term, cumulative effects of nuclear waste disposal, the use of atomic bombs for construction projects, and the potential ecological devastation wrought by nuclear war. Their new environmental awareness prompted many Atomic Energy Commission ecologists to try to draw congressional attention to the dangers that nuclear technology posed to the environment. It also spurred reforms in the education and training of ecologists to meet the challenges of the atomic age through the new subfield of "radioecology" as well as research into problems of environmental pollution more broadly. [ABSTRACT FROM AUTHOR]

Gamma ray spectrometric technique has been used to determine activity concentrations of some primordial radionuclides in the naturally occurring uranium, actinium and thorium series and of non-series40K in soil samples collected from five major towns in Oyo State, Southwestern Nigeria. Activity concentration determination was done using a high purity germanium (HPGe) detector. It ranged from 85.83 ± 4.04 Bq kg−1to 1,850.60 ± 36.83 Bq kg−1for40K; 5.23 ± 0.34 Bq kg−1to 198.31 ± 4.10 Bq kg−1for208Tl (indicator for232Th) and 7.82 ± 0.42 Bq kg−1to 64.65 ± 2.00 Bq kg−1for214Bi (indicator for238U). The outdoor absorbed dose rate in air due to each of the primordial radionuclides was calculated from the mean values of the activity concentration in each sample. Values ranged from 3.60 ± 0.17 nGy h−1to 77.73 ± 1.55 nGy h−1for40K, 3.48 ± 0.23 nGy h−1to 132.07 ± 2.73 nGy h−1for208Tl and 3.35 ± 0.21 nGy h−1to 27.73 ± 0.86 nGy h−1for214Bi. The absorbed dose rate in air was the highest for rocky areas, while the lowest value came from non-rocky, non-industrialized areas. The estimated annual outdoor effective dose equivalents for the two rocky areas were 385.76 μSv y−1and 221.28 μSv y−1. The estimated annual outdoor effective dose equivalents for the two industrialized areas were 64.05 μSv y−1and 47.65 μSv y−1. The value for non-rocky, non-industrialized areas was 19.19 μSv y−1. The average value for the study area was 147.59 μSv y−1. The estimated collective effective dose equivalent for the area was 9.77 × 102man-Sv y−1. The expected number of people in the study area at risk of incurring cancer per year as a result of radioactivity in the soil was estimated to be 11; this value represents approximately 7% of the estimated 160 people for 18 Nigerian cities, approximately 69% of 16 people estimated for oil producing areas of Nigeria and less than the United States Environmental Protection Agency regulatory limit of 1 cancer case to 10,000 people. Also, this result shows that local variability of natural radionuclides in soil depends on local geology of the area. The incidence number was 2.4 people per million. [ABSTRACT FROM AUTHOR]

In this article, the author focuses on the concerns pertaining to conservation of management of nature, citing role of human ecology, as of June 2013. It states the impact of human activities on nature, citing examples like the oil spill of petroleum company British Petroleum in 2010, and release of radioactivity at Fukushima Daiichi Nuclear Power Plant in Japan. He highlights findings of a study inferring transformation in the Earth's biosphere, that was published in the journal "Nature."