RESUMEN
Airborne radioruthenium, as a result of an accidental release, presents a risk for occupational and public exposure. In fall 2017, a detection of 106Ru was reported by the European atmospheric radioactive contamination monitoring networks. We investigated the daily specific total beta activity of PM10 particle fractions samples. The presented method enables indirect determination of airborne 106Ru activity concentration from total beta activity, in case 106Ru was confirmed as single excess radiological pollutant. This allows for daily measurements and time-resolved 106Ru activity concentration data. We estimated the indicative committed effective dose due to 106Ru inhalation for the Croatian population during the exposure period. Although the estimated dose value of ~169.7 nSv, for ~6-d duration of ruthenium air pollution, was very low, it was ~40 times higher than the value for Hinh from inhalation of other radionuclides (90Sr + 137Cs + 40K + 7Be).
Asunto(s)
Radioisótopos de Cesio , Radioisótopos de Rutenio , Berilio , Radioisótopos , Radioisótopos de Rutenio/análisis , Radioisótopos de EstroncioRESUMEN
The aim of this study was to provide baseline radioecological data for the temperate forest ecosystem in Plitvice Lakes National Park. Emphasis was placed on the determination of naturally occurring radionuclides since there is an acknowledged lack of data for these radionuclides in non-accident conditions in wildlife, even for bioindicator organisms. Activity concentrations of 238U, 226Ra, 210Pb, 232Th, 40K, 134Cs, and 137Cs were measured by gamma spectrometry in soil and bioindicators: earthworms, conifer needles, mosses, and lichens. From the measured activity concentrations, concentration ratios were calculated to quantify the transfer of these radionuclides from soil to bioindicators. Our results show that soil activity concentrations are biased toward results from other studies conducted within the Dinaric mountain region. However, in moss and lichen samples, we measured higher activity concentrations of 226Ra and lower activity concentrations of 40K and 137Cs in comparison to similar studies. Also, we estimated lower concentration ratios for all radionuclides from soil to these organisms, except for 210Pb, in comparison to generic values. The transfer of 238U was generally low for all of the bioindicator organisms. For conifer needles, a correlation was found between activity concentrations of 226Ra and 137Cs in soil and related concentration ratios. Correlation was also found between the activity concentration of 40K in soil and transfer of 40K and 137Cs to mosses and lichens. A comparison with literature data highlighted the lack of 226Ra related concentration ratios for conifer trees and especially for earthworms. Therefore, the results of this study could supplement the sparse data currently available on radionuclide background data in similar ecosystems and related soil-to-wildlife transfer of radionuclides. Dose rate assessments, performed by the ERICA Tool, estimated that 96% of the overall exposure of wildlife in the Park area is due to the background dose rates, while 0.06 µGy h-1 on average can be attributed as an incremental dose rate from 134Cs and 137Cs.
Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo/análisis , Uranio/análisis , Croacia , Ecosistema , Biomarcadores Ambientales , Bosques , Lagos , Parques Recreativos , SueloRESUMEN
This paper presents the results of long-term investigations of 137Cs activity concentrations in chicken meat and eggs from northwest Croatia for the period 1987-2018. The research has been done as a part of monitoring program of radioactive contamination in Croatia. The highest activity concentrations in both of these foodstuffs were measured in 1987 and have been decreasing exponentially ever since. The Fukushima-Daiichi accident in 2011 did not cause any increase of 137Cs activity concentrations. The ecological half-life for 137Cs was estimated to be 8.0 and 8.4 years for chicken meat and eggs respectively. The correlation between 137Cs in fallout and chicken meat as well as between 137Cs in fallout and eggs is very good, the respective correlation coefficients being 0.79 and 0.72, indicating that fallout was the main source of 137Cs contamination in both foodstuffs. The estimated effective doses received by adult members of the Croatian population due to the intake of radiocaesium by chicken meat and egg consumption for the overall observed period are very small, 2.0 and 0.6 µSv respectively. Therefore, chicken meat and chicken egg consumption was not a critical pathway for the transfer of radiocaesium to humans.
Asunto(s)
Radioisótopos de Cesio/análisis , Pollos , Huevos/análisis , Contaminación Radiactiva de Alimentos/análisis , Productos Avícolas/análisis , Animales , Radioisótopos de Cesio/farmacocinética , Accidente Nuclear de Chernóbil , Croacia , Semivida , Monitoreo de Radiación , Ceniza RadiactivaRESUMEN
The aim of this study was to assess the environmental radiological risk of coal ash and slag to terrestrial wildlife. The research site used in this study was a disposal site of coal ash and slag with enhaced content of uranium decay chain radionuclides. With the use of the ERICA Tool, total dose rates to wildlife and risk of resultant radiobiological effects were estimated. As input data for the assessment, experimental activity concentrations of 238U, 226Ra and 210Pb in coal ash and slag and best estimates of activity concentrations for related daughter radionuclides and 235U decay chain were used. Where possible, the experimental data for activity concentrations of 238U, 226Ra and 210Pb in plants and related concentration ratios were used. Results were compared to background dose rates, also estimated by the Tool. The Tool's assessment data indicated internal exposure as the prevalent exposure pathway with 226Ra and 210Po as the main dose contributors. Also, the contribution of 235U decay chain to the total dose rate was not negligible since for some organisms it represented up to 11% of the total dose rate. The risk of an occurrence of radiobiological effects in plants on the coal ash and slag disposal site can be considered negligible since the estimated total dose rates were below the screening dose of 10⯵Gyh-1 and near the dose rates estimated for plants in the control area. However, the estimated dose rates for reference animals and Lichen & Bryophytes were above the screening dose rate for most organisms and on average 13 times higher than the estimated background dose rates. At the given dose rates, an occurrence of different radiobiological effects could not be excluded for animals in close contact with coal ash and slag such as earthworms and small burrowing mammals. A separate assessment performed on an example of reference plants showed that the use of activity concentrations in organisms as input data can result in an order of magnitude smaller estimates of dose rates in comparison to activity concentration in coal and ash as input data. Our study highlighted the need for experimental data in radiological risk assessments to mitigate the conservatism of the ERICA Tool and its tendency to overestimate dose rates.
Asunto(s)
Ceniza del Carbón/análisis , Monitoreo de Radiación/métodos , Medición de RiesgoRESUMEN
This study investigates multi-element composition of soil, mosses and mushrooms from a pristine temperate rainforest (Prasnik, Croatia). Additionally, the activity levels of natural (238U, 235U and 232Thâ¯decay chains, 40K and 7Be) and anthropogenic (137Cs and 134Cs) radionuclides in the investigated soil samples, obtained by gamma spectrometry, provide baseline of environmental radioactivity levels in this area. The aim of investigation was to explore the uptake of metal(loid)s by bioindicator species (mosses, mushrooms) growing in a pristine environment characterized by naturally elevated concentration of metals. The calculated enrichment and bioaccumulation factors, correlations between different groups of elements and similar multi-element patterns in mosses, mushrooms and soil samples revealed the prevailing influence of the local substrate geochemistry on element concentrations in mosses and mushrooms. The results suggest atmospheric deposition of Bi, Cd and Pb, while radionuclide activities point to atmospheric fall-out (including global contamination by radiocaesium) and influence of the pedological substrate. The confined area of investigation, with limited variations in soil characteristics and geological composition, allowed clearer insight into the origin of metal(loid)s in mosses and mushrooms. On the other hand, using bioindicator species with different element uptake mechanisms enabled distinction between different sources of elements.
Asunto(s)
Briófitas/metabolismo , Radiactividad , Radioisótopos/farmacocinética , Bosque Lluvioso , Suelo/química , Agaricales/química , Agaricales/metabolismo , Briófitas/química , Croacia , Monitoreo del Ambiente/métodos , Metales/análisis , Contaminantes del Suelo/análisis , Espectrometría gammaRESUMEN
In this study, the influence of anthropogenic pollution on the aquatic environment of Plitvice Lakes National Park (PLNP) was investigated during 2011-2012 using a combination of chemical and cytogenetic analyses. Four groups of major contaminants [(volatile organic compounds: benzene, toluene, ethylbenzene, and xylenes (BTEX); persistent organochlorine pollutants: organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs); major and trace elements; anthropogenic radionuclides (90Sr, 134Cs, and 137Cs)] were determined in three aquatic compartments (water, sediment, fish). Mass fractions of inorganic constituents in different compartments reflected the geological background of the area, indicating their origin from predominantly natural sources. Levels of volatile and persistent organic compounds in water and fish, respectively, were very low, at levels typical for remote pristine areas. Analysis of anthropogenic radionuclides in water and sediment revealed elevated activity concentrations of 137Cs in water, and measurable 134Cs in the upper sediment layers from April 2011, possibly as a consequence of the Fukushima nuclear accident in March 2011. The potential genotoxicity of river and lake water and lake sediment was assessed under laboratory conditions using the alkaline comet assay on human peripheral blood lymphocytes, and measured levels of primary DNA damage were within acceptable boundaries. The results showed that despite the protected status of the park, anthropogenic impact exists in both its terrestrial and aquatic components. Although contaminant levels were low, further monitoring is recommended to make sure that they will not rise and cause potentially hazardous anthropogenic impacts.
Asunto(s)
Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Sedimentos Geológicos/química , Lagos/química , Ríos/química , Contaminantes Químicos del Agua/análisis , Animales , Radioisótopos de Cesio/análisis , Croacia , Daño del ADN/genética , Peces , Humanos , Linfocitos/efectos de los fármacos , Pruebas de Mutagenicidad , Parques Recreativos , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Radioisótopos de Estroncio/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
The results of long-term investigations into the post-Chernobyl period of radiocesium activity concentrations in cistern waters along the Croatian coast of the Adriatic Sea are presented. The Cs activity concentrations in cistern water samples were in excellent correlation with fallout activities. The observed mean residence time of Cs in cistern waters was estimated to be 6.9 ± 0.8 y. Cesium-137 radioecological sensitivity for the period 1988-1997 for cistern water was estimated to be 1.17 × 10 Bq y L/(Bq m). The annual total effective dose incurred by Cs and Cs that a hypothetical adult person drinking 1 L of cistern water per day would receive was estimated to be < 1 mSv in 1986, decreasing to 3.6 µSv in 2015.
Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Océanos y Mares , Monitoreo de Radiación , Agua/química , Croacia , Ceniza RadiactivaRESUMEN
The aim of this study was to investigate the uptake of 238U, 235U, 232Th, 226Ra, 210Pb and 40K by plants that grow on a coal ash and slag disposal site known for its higher content of naturally occurring radionuclides. Plant species that were sampled are common for the Mediterranean flora and can be divided as follows: grasses & herbs, shrubs and trees. To compare the activity concentrations and the resultant concentration ratios of the disposal site with those in natural conditions, we used control data specific for the research area, obtained for plants growing on untreated natural soil. Radionuclide activity concentrations were determined by high resolution gamma-ray spectrometry. Media parameters (pH, electrical conductivity and organic matter content) were also analysed. We confirmed significantly higher activity concentrations of 238U, 235U, 226Ra and 210Pb in ash and slag compared to control soil. However, a significant increase in the radionuclide activity concentration in the disposal site's vegetation was observed only for 226Ra. On the contrary, a significantly smaller activity concentration of 40K in ash and slag had no impact on its activity concentration in plant samples. The calculated plant uptake of 238U, 235U, 226Ra and 210Pb is significantly smaller in comparison with the uptake at the control site, while it is vice versa for 40K. No significant difference was observed between the disposal site and the control site's plant uptake of 232Th. These results can be the foundation for further radioecological assessment of this disposal site but also, globally, they can contribute to a better understanding of nature and long-term management of such disposal sites.
Asunto(s)
Plantas/metabolismo , Residuos Radiactivos/análisis , Contaminantes Radiactivos del Suelo/análisis , Biodegradación Ambiental , Ceniza del Carbón/análisis , Radioisótopos de Plomo/análisis , Plantas/química , Radioisótopos de Potasio/análisis , Monitoreo de Radiación , Radio (Elemento)/análisis , Contaminantes Radiactivos del Suelo/metabolismo , Torio/análisis , Uranio/análisisRESUMEN
The anthropogenic impact on the terrestrial environment of the Plitvice Lakes National Park (PLNP) was investigated through the analysis of three groups of major contaminants (persistent organochlorine pollutants including 15 organochlorine pesticides (OCPs) and 17 polychlorinated biphenyls (PCBs), trace elements/heavy metals (6 major and 23 trace constituents), and anthropogenic radionuclides ((90)Sr, (134)Cs, and (137)Cs)) in three terrestrial compartments (soil, air, and bioindicators of air contamination) during 2011-2013. The correlation coefficients of element mass fractions with soil properties indicated that total Fe and Al minerals, soil organic matter (OM), and organic carbon (OC) content affected the mass fractions of most trace elements in the topsoils. The annual and spatial distributions of heavy metals in total deposited matter (TDM) indicated that the metals came from natural sources and long-range transfer of particulate matter. The PCB and OCP levels found in soil and conifer needles corresponded to global environmental pollution levels by persistent organic pollutants and represented the lower end of the mass fraction ranges reported in the relevant literature. Analyses of anthropogenic radionuclides in bioindicators (conifer needles, lichens, and mosses) showed low but measurable activity concentrations of (134)Cs (for the first time after the Chernobyl accident), which indicated origin from the March 2011 Fukushima Nuclear Power Plant accident. Our overall results indicated that human activity inside or near the PLNP had no significant impact either on contaminant spread by air or on their content in topsoils.
Asunto(s)
Monitoreo del Ambiente , Parques Recreativos , Contaminantes Químicos del Agua/análisis , Briófitas , Croacia , Contaminación Ambiental/análisis , Humanos , Hidrocarburos Clorados/análisis , Lagos/química , Líquenes , Metales Pesados/análisis , Material Particulado/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Radioisótopos/análisis , Oligoelementos/análisisRESUMEN
Phosphogypsum (PG) is a waste product (residue) from the production of phosphoric acid characterized by technologically enhanced natural radioactivity. Croatia's largest PG deposition site is situated at the edge of Lonjsko Polje Nature Park, a sensitive ecosystem possibly endangered by PG particles. This field study investigates two aspects relevant for the general radiological impact of PG: risk assessment for the environment and risk assessment for occupationally exposed workers and local inhabitants. Activity concentrations of natural radionuclides ((238)U, (235)U, (232)Th, (226)Ra, (210)Pb, and (40)K) were measured in the PG (at the deposition site), soil, and grass samples (in the vicinity of the site). The ERICA Assessment Tool was used to estimate the radiological impact of PG particles on non-human biota of the Lonjsko Polje Nature Park. The average annual effective dose for occupationally exposed workers was 0.4 mSv which was within the worldwide range.
Asunto(s)
Sulfato de Calcio/análisis , Fósforo/análisis , Plantas/química , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Anfibios/fisiología , Animales , Aves/fisiología , Croacia , Monitoreo del Ambiente , Humanos , Mamíferos/fisiologíaRESUMEN
Phosphogypsum (PG), a waste product in phosphate fertilizer production, is characterized by technically enhanced natural radioactivity. The presented investigation was performed on a PG deposition site in Croatia. A new approach in the determination of the spread of PG particles from the deposition site into the environment based on the PG particle radioactivity measurements is suggested and explained. The stationary diffusion model was assumed and employed to describe long term PG particle transfer into the surroundings. The advantage of this method is that it requires a minimal number of measurement locations and offers a realistic and reliable distribution of PG particles. The mass concentration of PG particles decreased to the distance of about 3m, at most up to 10 m from the deposition site edge. The results indicate that a unique mechanism of particle transport exists and the migration of PG particles by surface water is the dominant way of their spread. The particle current deduced from the measurements was very low, approximately 4.05 × 10(-2)kg/h, and the migration coefficient was approximately 1.69 × 10(-5)m(2)/h. The obtained results confirmed the initial hypothesis of the stationarity of the migration process, reached within about 6 years.
Asunto(s)
Sulfato de Calcio , Modelos Teóricos , Fósforo , Contaminantes del Suelo , Difusión , Fertilizantes , Sitios de Residuos Peligrosos , Residuos Industriales , Movimientos del Agua , VientoRESUMEN
Investigations in the post-Chernobyl period (1986-2009) of radiocaesium activity concentrations in Adriatic pilchards are presented. Compared with pre-Chernobyl period, the Chernobyl nuclear accident caused increase of (137)Cs activity concentrations in pilchards. By fitting the measured (137)Cs activity concentrations to the theoretical curve was estimated to be 1.5±0.4 y for 1986-90 and 5.8±0.4 y for 1991-2009 and the bimodal behaviour for the ecological half-life of (137)Cs in pilchards has been observed. Estimated annual effective doses received by (134)Cs and (137)Cs intake due to consumption for an adult member of Croatian population are small. Collective dose for the 1986-2009 period was 4.9+0.3 person-Sv. The observed (134)Cs/(137)Cs activity ratio in pilchards was similar to the ratio that has been found in other environmental samples. The concentration factor for pilchards was roughly estimated to be 93.7±39.2 l kg(-1), which is consistent with the values observed elsewhere.
Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Peces/metabolismo , Contaminación Radiactiva de Alimentos/análisis , Monitoreo de Radiación , Ceniza Radiactiva/análisis , Adulto , Animales , Croacia , HumanosRESUMEN
Natural radioactivity of Middle-Adriatic Sea islands and islets was measured. Gamma spectrometric measurements, both in situ and in laboratory, as well as radon measurements in the seawater were performed. Activity concentrations and the associated dose rates due to naturally occurring (232)Th, (238)U and (40)K radioisotopes were determined. Dose rates calculated from in situ gamma spectrometry are in correlation with dose rates calculated from activity concentrations measured in collected samples of pebbles and rocks. In situ gamma ray spectrometry in the seawater has been performed, showing activity concentration of 220 and 240 Bq m(-3) for (214)Bi and (214)Pb, respectively due to the presence of magmatic rocks in the seabed. The radium equivalent activity varied from 13 to 53 Bq kg(-1). These values are lower than the limit values, indicating that the radiation hazard is not significant. The highest mean activity concentrations of naturally occurring radionuclides in rock samples collected were found on the islands of magmatic origin.
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Dosis de Radiación , Radiometría , Contaminantes Radiactivos del Suelo/análisis , Rayos gamma , Islas del MediterráneoRESUMEN
Thermal waters are known as valuable natural resources of a country. They contain certain degree of natural radioactivity attributable to the elements of the uranium and thorium natural decay series. Among these elements, the most radiotoxic and the most important is radium that exists in several isotopic forms (226Ra and 228Ra). The focus of attention was the content of radium in samples of thermal and mineral spring water from several spas in Croatia. These waters are mainly used for medical, bathing and recreational purposes, and some of them are used for drinking. Measured activity concentrations of 226Ra ranged from 87 to 6200 mBq l(-1) which, in some springs, exceed the maximal permissible level of 1 Bq l(-1) for drinking water. Measured activity concentrations of 228Ra ranged from 23 to 3480 mBq l(-1). The study showed that radium content for the investigated thermal and mineral waters is below the levels at which negative consequences would arise due to ingestion.
Asunto(s)
Radiación de Fondo , Manantiales de Aguas Termales/química , Aguas Minerales/análisis , Monitoreo de Radiación , Radón/análisis , Contaminantes Radiactivos del Agua/análisis , Croacia , Dosis de RadiaciónRESUMEN
Radiation dosimetry in protection against ionising radiation involves research of all possible pathways through which natural or man-made radioactive materials can contaminate a habitat and actually harm its biota. It also takes into account natural and artificial (man-made) electromagnetic ionizing radiation (gamma and x radiation). This article presents a dosimetric study assessing exposure to man-made ionising radiation of local environment and total occupational exposure of two professional workers involved in characterisation, conditioning, and securing of unused radioactive sealed sources. The purpose of the study was to validate a new active electronic dosimeter (AED) of type ALARA OD and to develop a new monitoring method by tracing the external occupational exposure over real time. This method is used to continuously measure and record external radiation doses and, which is a novelty, establish dose rates receiving pattern as a function of real time. Occupational whole body dosimetric results obtained with AED were compared with results obtained with passive dosimetry (film badge and thermoluminiscence). Air, dust, and silicon sand samples were analysed by gamma-spectrometry to estimate internal exposure of the two workers to 222Rn due to inhalation or ingestion of dust and sand in indoor air. In order to establish total occupational exposure, control radon measurement was performed in the immediate environment and the external Hazard index (Hex) was calculated.
Asunto(s)
Exposición Profesional , Dosis de Radiación , Monitoreo de Radiación , Radiometría/instrumentación , Contaminantes Radiactivos del Aire/análisis , Radiación de Fondo , Humanos , Protección Radiológica , Radón/análisisRESUMEN
The contents of natural radionuclides (radium, uranium and potassium) were measured in the area of a phosphate fertilizer factory in central Croatia, as a part of extended and still ongoing monitoring program of radioactive contamination of human environment in Croatia that is performed by the Radiation Protection Unit of the Institute for Medical Research and Occupational Health in Zagreb. Activity concentrations in all analysed media (waste water, trickling water from piezometers, phosphogypsum deposit and final products) considerably fluctuated, especially in phosphogypsum and waste water. Mean (226)Ra activity concentration in waste phosphogypsum was measured to be 483+/-190 Bqkg(-1). Based on that value, it was estimated that 4 million m(3) of phosphogypsum that have been deposited up to now contain about 4.3 x 10(12) Bq, i.e. about 200 g of (226)Ra. However, effective dose for an adult that would be incurred by consumption of water from nearby wells was estimated to be 5.3+/-1.3 microSv. The results show that (226)Ra activities cause effective doses, which are below the recommended maximum as the estimated annual (226)Ra effective dose does not exceed 0.1 mSv as recommended by the World Health Organization.
Asunto(s)
Fertilizantes , Fosfatos/análisis , Contaminantes Radiactivos/análisis , CroaciaRESUMEN
The long-term behaviour of (137)Cs activity concentrations in air and fallout has been studied in the city of Zagreb for the post-Chernobyl period (1986-2006) as a part of an extended monitoring program of radioactive contamination of human environment in Croatia. Annual mean (137)Cs activity concentrations in air and annual total deposition fluxes (wet plus dry) decreased from 2.8 x 10(-4) Bq m(-3) in September 1986 to 3.0 x 10(-6) Bq m(-3) in last quarter of 2006 and from 6,410 Bq m(-2) year(-1) in 1986 to 2 Bq m(-2) year(-1) in 2006 respectively. By fitting the measured (137)Cs activity concentrations to the theoretical curve the ecological half-lives of (137)Cs in air and fallout were estimated with respective values of 0.46 and 0.54 years for immediate post-Chernobyl period, increasing to 5.52 and 3.97 years afterwards. Using the data on (137)Cs activity concentrations in air and fallout total caesium deposition velocity of (3.34 +/- 3.13) x 10(-2) ms(-1) was estimated with median value being 2.13 x 10(-2) ms(-1). Such relatively high (137)Cs deposition velocities compared with pre-Chernobyl ones, are characteristic for the post-Chernobyl period and, according to Stokes' settling law, indicate that the diameters of aerosol particles associated with (137)Cs originated from the Chernobyl accident are pretty large, i.e. >1 microm. (134)Cs/(137)Cs activity ratio in fallout and in air has been found to be similar to the theoretically predicted values, initial value being about 0.5 and decreasing according to differential radioactive decay. The similar ratio has been observed in most of the other environmental samples.
Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Ceniza Radiactiva/análisis , Croacia , Humanos , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo/análisis , Factores de TiempoRESUMEN
Long-term investigations of radiocaesium activity concentrations in beef in the Republic of Croatia are presented. The radiocaesium levels in beef decreased exponentially and the effective ecological half-life of 137Cs was estimated to be 0.57+/-0.06 years for 1986-1990 period and 5.21+/-0.27 years for the 1991-2005 period. For 1986-1990 period, the effective ecological half-life of 134Cs in was estimated to be about 0.69+/-0.05 while 134Cs activity concentrations after year 1990 were below the detection limit of the instruments. The 134Cs:137Cs activity ratio in beef has been found to be similar to the ratio that has been observed in other foodstuffs and environmental samples. Radioecological sensitivity for beef meat, i.e., the transfer coefficient from fallout to sample was estimated to be 1.15x 10(-2)Bqykg(-1)/(Bqm(-2)). For an adult member of Croatian population annual effective doses received by 134Cs and 137Cs intake due to consumption of beef are small, as per caput effective dose for the overall 1986-2005 period was estimated to be 24.6microSv. Consequently, after the Chernobyl accident beef consumption was not a critical pathway for the transfer of radiocaesium from fallout to humans in Croatia.
Asunto(s)
Radioisótopos de Cesio/análisis , Accidente Nuclear de Chernóbil , Contaminación de Alimentos/análisis , Carne/análisis , Algoritmos , Animales , Bovinos , Croacia , Semivida , Humanos , Modelos Estadísticos , Ceniza Radiactiva/análisis , RadiometríaRESUMEN
Mosses, lichens, mushrooms are able to efficiently accumulate different radioactive elements from their environment to a much higher degree than other vegetation. They are sensitive bioindicators of radioactive contamination for various ecosystems, particularly in the event of a nuclear accident and uncontrolled emission oh fission products. Results of systematic, long-term measurements of 137Cs activities in mosses and in some edible mushroom species in North Croatia for the post-Chernobyl period (1986-2007) are summarized. The study was conducted in the Radiation Protection Unit of the Institute for Medical Research and Occupational Health in Zagreb, as a part of an extensive monitoring program of the Croatian environment. In the overall observed period the highest activity concentration of 137Cs deposited by fallout has been recorded in 1986, which is the year of Chernobyl accident, causing peak S7Cs activity concentration in moss of 8800 Bq/kg in May 1986. In the same period mean 137Cs activity concentration in grass was 390 Bq/kg. The highest value of 137Cs activity concentration in Cortinarius caperatus mushrooms of 1351 Bq/kg has been recorded in 1989. Fitting the measured 137Cs activity concentrations to the theoretical curve the ecological half-life of 137Cs in moss was found to be around 978 days, in grass around 126 days in the period 1986-1990, in Cortinarius caperatus mushroom around 5865 days (16.1 years). Regarding the risk assessment to Croatian population, due to consumption of mushrooms, the collective effective dose for Croatian population, estimated to be about 35 mSv per year, was found to be quite low. Therefore, it can be concluded that mushroom consumption was not a critical pathway for the transfer of radiocaesium from fallout to humans after the Chernobyl accident.