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1.
The objective of this study is to evaluate natural and artificial radioactivity levels in 18 different samples of medicinal herbs from Serbian market. The activity concentrations of (238)U, (232)Th, (40)K, and (137)Cs were measured using gamma spectroscopy system with a high-purity germanium detector. The activity concentrations of (238)U, (232)Th, (40)K, and (137)Cs were found to be in a range of 0.6-8.2, 1.7-15.1, 126-1243.7, and 0.3-8.8 Bq/kg, respectively. The annual whole body doses from ingestion of (137)Cs and natural radionuclides for an adult person who consumed herbal tea from these medicinal herbs were found to be 2.5-469.9 nSv for (137)Cs, 0.7-9.7 nSv for (238)U, 0.3-2.8 nSv for (232)Th, and 1026.0-10,132.0 nSv for (40)K. These doses are not hazardous to public health. The obtained results were compared with correspondent studies conducted worldwide.  相似文献   

2.
Amanita muscaria collected from a forested area in northern Poland in 2015 were analysed for activity concentrations of 137Cs and 40K. Total K concentration values were calculated from 40K data. Mushrooms were grouped in six fruiting bodies size classes regarding to their developmental stage. The 137Cs activity concentrations declined in A. muscaria as the fruiting bodies maturated. The contents of 40K/K activity remained constant in caps at different developmental stage, while for stipes an increase was around twofold (40K from 925?±?55 Bq kg?1 dry biomass in the baby individuals and 1600?±?63–1700?±?53 Bq kg?1 dry biomass in two oldest classes). A. muscaria is a weak accumulator of 137Cs, while a steep drop in activity concentrations of this nuclide in the fruiting bodies as they maturate has not been reported earlier for mushrooms. Clearly, a fate of 137Cs in A. muscaria is highly different from that of 40K/K that is an essential element to fungi. In parallel, an observed increase in the content of 40K/K in stipes of fruiting bodies with developmental state can be related to its ‘hardening’ and more fibrous nature with age and basic function to support the cap, but this has not been studied.  相似文献   

3.
An extensive study was conducted to determine the activity concentrations of natural and artificial radionuclides 226Ra, 232Th, 40K, and 137Cs in soil samples of each governate of Jordan. A total of 370 samples have been measured using a high-purity germanium detector. The activity concentration for 226Ra, 232Th, 40K, and 137Cs has mean values of 42?±?3, 23?±?3, 309?±?21, and 3.7?±?0.9 Bq kg–1, respectively. The highest mean activity concentration for 226Ra was found to be 138?±?4 Bq kg–1 in the Alkarak governate. In the Ajloun and Jarash governates, the highest mean activity concentration was 35?±?3 Bq kg–1 for 232Th, and 14.2?±?1.9 Bq kg–1 for 137Cs, respectively. Geological influence on the activity concentrations was investigated using the one-way analysis of variance (ANOVA) and independent samples. The ANOVA results indicate that there are strong significant differences between the activity concentrations of 232Th, 40K, and 137Cs based on geological formations the radionuclides occur. The main contribution to gamma dose rate was due to 226Ra activity concentration. Radium equivalent and external hazard index are associated with a mean value of 98 Bq kg–1, and 0.266, respectively.  相似文献   

4.
Transfer coefficients of 137Cs from soil to grass were determined for the terrain around the city of Kragujevac in central Serbia. Mass activity concentrations of 137Cs in soil and grass samples were determined with a high-purity Ge-detector (HPGe). The activity concentration at the depth of 20 cm was found to be in the range of 14.92–124.05 Bq kg?1, whereas the activity in grass for the same location was in the range of 4.60–84.95 Bq kg?1. Transfer factors (TFs) were in the range of 0.07 up to 1.94.

Dependences of TFs on different soil characteristics were presented graphically. Weak dependences were determined between them. Absalom's model was used to predict TFs based on soil characteristics: pH value, contents of clay, exchangeable potassium and humus.

A comparison of measured and predicted values from Absalom's model is shown graphically. It has been found that Absalom's model might be carefully used for the prediction of 137Cs in grass for specific regions.  相似文献   

5.
ABSTRACT

Three soil depth profiles of 210Pb, 137Cs and 40K at different areas of Algeria were studied. The soil sampling areas are near the location where the French nuclear tests took place at 1960–1966. The two depth soil profiles were collected at Ghardaia region and the third one at Reggane region. The vertical distributions of radionuclides at the two soil depth profiles from Ghardaia region are different, probably due to the different soil composition. The soil depth profile from sandy soil show uniformity in the distribution of radionuclides without a clear maximum (peak). The soil depth profile that characterised by silty sand show a clear peak at 20–50?cm depth for all studied radioactive nuclides, while the observed activities are two times higher than the corresponding values in sandy soil samples. More specifically in Ghardaia region the 210Pb, 137Cs, 40K activity concentrations ranged between 27 and 50?Bq?kg?1, 0.2 and 3?Bq?kg?1 and 75 and 90?Bq?kg?1 respectively in sandy soil type and between 37 and 75?Bq?kg?1, 4 and 6?Bq?kg?1 and 140 and 180?Bq?kg?1 respectively in silty sand soil type. Finally, the third depth soil profile collected from Reggane site presents a completely different distribution of the studied radionuclides. The activity concentrations of 210Pb, 137Cs, 40K ranged between 37 and 51?Bq?kg?1, 0.16 and 0.39?Bq?kg?1 and 120 and 309?Bq?kg?1 respectively. Three peaks in the 137Cs distribution revealed, were most probably, Chernobyl related 137Cs accounts for the surface peak, while the deeper peaks are connected to the weapons fallout.  相似文献   

6.
The activity concentrations of gamma emitting radionuclides were measured in surface soil samples from the Thrace region. 232Th, 238U, 226Ra, 40K and 137Cs activities and physico-chemical parameters of the soil samples were determined in samples collected from 73 sampling stations. Radionuclide concentrations measured were compared with those found in the samples from other locations of Turkey and from different countries. The average activity concentrations of 232Th, 238U, 226Ra, 40K and 137Cs were found to be 24.71 ± 8.79, 22.30 ± 7.93, 32.09±12.44, 509.00±160.05, 32.74±29.24 Bq kg?1, respectively. The mean value of the annual effective dose equivalent from the outdoor terrestrial gamma radiation was calculated as 57.2 μ Sv.  相似文献   

7.
About 21 years after the Chernobyl accident, 137Cs and 40K activity concentration measurements using gamma-ray spectroscopy and elemental analysis using energy dispersive X-ray spectroscopy were performed in five different lichen species collected from the Giresun province of northeastern Turkey. Being a symbiosis of algae and fungi, lichens are mostly used for environmental measurements since the fungal partner is responsible for the uptake of necessary nutrients or harmful substances, such as heavy metals of radionuclides. The gamma activity results showed that 137Cs, an artificial radionuclide released from the Chernobyl power plant accident, is still eminent in the environment of the province. The mean activity concentrations of 137Cs and 40K ranged from 24 to 254 with the mean value of 102 Bq kg?1 and from 345 to 2103 with the mean value of 1143 Bq kg?1 in dry weight. The results of the elemental analyses showed potassium, calcium, titanium, iron, tin, and barium in different concentrations.  相似文献   

8.
The current study presents the results of the activity of radionuclides in spa waters, and evaluates their radiological influences on the population consuming these waters in the Central and Eastern Black Sea regions of Turkey. Since these waters are used for therapy and consumption purposes unconsciously, their radiological impact on the people was computed by taking into consideration the annual intake through ingestion of 226Ra, 232Th, 40K, 137Cs and 222Rn. The mean activities were estimated to be 11.35 for gross alpha, 6.23 for gross beta, 2.96 for 226Ra, 0.42 for 232Th, 0.069 for 137Cs, 0.19 for 40K, and 267 Bq L–1 for 222Rn, respectively. The estimated effective doses from spa water were found to be 49.77 µSv a–1 (226Ra), 5.95 µSv a–1 (232Th), 0.07 µSv a–1 (137Cs), 0.83 µSv a–1 (40K) and 56.03 µSv a–1 (222Rn). These values were evaluated and compared with related verified values from literature. Also, physico-chemical characterizations of spa water samples considered in the current study were investigated. This study would be useful for consumers and official authorities for the assessment of radiation exposure risk due to usage of the considered spa waters.  相似文献   

9.
The analysis of gamma-emitting radionuclides in nature, i.e. 226Ra, 232Th, 40K and 137Cs, has been carried out in soil samples collected from Peshawar University Campus and surrounding areas using a high purity germanium detector coupled with a computer-based high-resolution multichannel analyser. The activity concentrations in soil ranged from 30.20±0.65 to 61.90±0.95, 50.10±0.54 to 102.80±1.04, 373.60±4.56 to 1082±11.38 and 9.50±0.11 to 46.60±0.42 Bq kg?1 for 226Ra, 232Th, 40K and 137Cs, with a mean value of 45±7.70, 67±12.50, 878±180 and 19±9.20 Bq kg?1, respectively. The radium equivalent activity, internal and external hazard indices have mean values of 203.40±29.40 Bq kg?1, 0.56 and 0.68, respectively. The mean values of outdoor and indoor absorbed dose rates in air and the annual effective dose equivalents were found to be 106.50 and 128 nGy h?1 and 0.19 and 0.54 mSv y?1, respectively. In the present study, 40K was the major radionuclide present in soil samples. The presence of 137Cs indicates that this area also received some fallout from the nuclear accident of the Chernobyl power plant in 1986. The activity concentrations of radionuclides found in soil samples during the current investigation were nominal. Therefore, they are not associated with any potential source of health hazard to the public.  相似文献   

10.
The activity concentration of natural (238U, 232Th, and 40K) and artificial (137Cs) radionuclides was determined in 50 samples (obtained from the same station) from various species of mushrooms and soil collected from the Middle Black Sea Region (Turkey). The activities of 238U, 232Th, 40K, and 137Cs were found as 84 ± 16, 45 ± 14, 570 ± 28, and 64 ± 6?Bq?kg–1 (dry weight), respectively, in the mushroom samples and as 51?±?6, 41?±?6, 201?±?11, and 44?±?4?Bq?kg–1, respectively, in the soil samples for the entire area of study. The results of all radionuclide activity measurements, except those of 238U and 232Th in the mushroom samples, are consistent with previous studies. In the soil samples, the mean values of 238U and 232Th are above the world mean, and the activity mean of 40K is below the world mean. Finally, the activity estimation was made with both the soil and mushroom samples for unmeasured points within the study area by using the ordinary kriging method. Radiological distribution maps were generated.  相似文献   

11.
Activity concentrations of 134Cs and 137Cs were determined in mushrooms of the Boletus species B. aereus, B. reticulatus, B. appendiculatus, B. calopus, B. edulis, B. erythropus, B. fechtneri, B. pinophilus, B. pseudoregius, B. rhodopurpureus, B. rhodoxanthus collected in the Reggio Emilia, Italy, in 1993 and 1994 and in B. edulis collected in Pomerania in northern Poland in the period from 1995–2015. Boletus edulis from the Reggio Emilia showed presence of 137Cs at 330?±?220?Bq?kg?1 dry biomass in 1993 and at 370?±?180?Bq?kg?1 dry biomass in 1994. In B. edulis sampled in the Reggio Emilia in 1993 and 1994, the pre-Chernobyl 137Cs from global fallout amounted to 39–46?% of the total activity concentrations of isotope 137Cs. B. edulis from Pomerania contained 137Cs in caps at 270?±?15?Bq?kg?1 dry biomass in 1995, and in whole fruiting bodies it was found to be 470?±?9?Bq?kg?1 dry biomass in 2015. The activity concentrations of 137Cs determined in fruiting bodies of B. edulis from Pomerania fluctuated but persisted over the period from 1995 to 2015, while the maximum activity concentrations were well below the tolerance limit of 600?Bq?kg?1 fresh product.  相似文献   

12.
A survey was conducted to evaluate levels of indoor radon and gamma doses in 42 primary schools located in Batman, southeastern Anatolia, Turkey. Indoor radon measurements were carried out using CR-39 solid-state nuclear track detector-based radon dosimeters. The overall mean annual 222Rn activity in the surveyed area was found to be 49 Bq m?3 (equivalent to an annual effective dose of 0.25 mSv). However, in one of the districts (Besiri) the maximum radon value turned out to be 307 Bq m?3. The estimated annual effective doses are less than the recommended action level (3–10 mSv). It is found that the radon concentration decreases with increasing floor number. The concentrations of natural and artificial radioisotopes were determined using gamma-ray spectroscopy for soil samples collected in close vicinity of the studied schools. The mean gamma activity concentrations in the soil samples were 31, 25, 329 and 12 Bq kg?1 for 226Ra, 232Th, 40K and 137Cs, respectively. The radiological parameters such as the absorbed dose rate in air and the annual effective dose equivalent were calculated. These radiological parameters were evaluated and compared with the internationally recommended values.  相似文献   

13.
222Rn (radon) is one of the most important sources of natural radiation to which people are exposed. It is an alpha-emitting noble gas and it can be found in various concentrations in soil, air and in different kinds of water. In this study, we present the results of radon concentration measurements in thermal waters taken from the sources in the region of Konya located in the central part of Turkey. The radon activity concentrations in 10 thermal water samples were measured by using the AlphaGUARD PQ 2000PRO radon gas analyser in spring and summer of the year 2012. We found that radon activity concentrations range from 0.60±0.11 to 70.34±3.55 kBq m?3 and from 0.67±0.03 to 36.53±4.68 kBq m?3 in spring and summer, respectively. We also calculated effective doses per treatment in the spas for the spring and summer seasons. It was found that the minimum and maximum effective doses per treatment are in the range of 0.09–10.13 nSv in spring and in the range of 0.1–5.26 nSv in summer.  相似文献   

14.
Twenty-two medicinal herb samples, each representing a distinct species, were collected from Turkish markets and measured by the gamma spectrometric method. The activity concentration of 226Ra in medicinal herbs was found in the range of minimum detectable activity (MDA) and 15.1?±?2.2?Bqkg?1. The activity concentration of 232Th ranged from MDA values to 3.5?±?0.8?Bqkg?1. The activity concentration of 40K varied between 50.0?±?16.8 and 1311.5?±?57.3?Bqkg?1. All 137Cs activity concentrations of medicinal herbs were found to have lower than MDA values. The bone surface dose, lower large intestine and colon doses were found to be 182.9, 18.8 and 18.7?µSvy?1, respectively. The highest committed effective dose originated from the annual ingestion of 1?kg medicinal herb was calculated notably low as 9.0?µSv. The cancer risk of ingestion of medicinal herbs was found to be small enough to be neglected. The selected Turkish medicinal herbs are considered safe for human consumption.  相似文献   

15.
The radioactivity levels are poorly studied in non-coastal arid regions. For this reason, 38 locations covering an area of about 350 km2 in northeast Sinai, Egypt, were investigated by γ-ray spectroscopy. Moderately significant correlations among 238U, 234Th, and 226Ra isotopes and low significant correlations between the concentrations of 238U-series and 232Th in sand were obtained. No evidence of correlation was found between the concentrations of radioisotopes and pH, grain size, total organic matter content, bicarbonate or calcium carbonate concentrations of the sand samples. The mean values of soil-to-plant transfer factor were 0.15, 0.18, 1.52 and 0.74 for 226Ra, 232Th, 40K, and 137Cs, respectively. The range of concentrations of 226Ra, 232Th, and 40K in water samples collected from five wells were<0.4–0.16,<0.4–0.13, and<0.15–1.62 Bq l?1, respectively. The mean absorbed dose rate in outdoor air at a height of 1 m above the ground surface for the sand samples was 19.4 nGy h?1. The Raeq activities of the sands are lower than the recommended maximum value of 370 Bq kg?1 criterion limit for building materials.  相似文献   

16.
Research of the effect of salinity on the fate of radionuclides has been focused on seas or estuarine systems while there is almost no information on marine environments with a salinity higher than that of sea water. The hypersaline Bardawil lagoon is a concentration basin, with evaporation exceeding precipitation. This study presents the characteristics of some environmental factors including salinity and their influence on the distribution of natural and artificial radionuclides in different compartments of the lagoon. The concentrations of 238U, 234Th, 228Ra and 137Cs in sediments show some degree of dependency on the water's salinity. Migration of these radionuclides in the lagoon's sediments must take place from high salinity to low-salinity regions. Cluster analysis revealed the data structure for sediment by separating 137Cs and 40K from 232Th, 226Ra, and 234Th and for sand by separating 40K from the other radioisotopes.  相似文献   

17.
Transfer coefficients of (137)Cs from soil to grass were determined for the terrain around the city of Kragujevac in central Serbia. Mass activity concentrations of (137)Cs in soil and grass samples were determined with a high-purity Ge-detector (HPGe). The activity concentration at the depth of 20 cm was found to be in the range of 14.92-124.05 Bq kg(-1), whereas the activity in grass for the same location was in the range of 4.60-84.95 Bq kg(-1). Transfer factors (TFs) were in the range of 0.07 up to 1.94. Dependences of TFs on different soil characteristics were presented graphically. Weak dependences were determined between them. Absalom's model was used to predict TFs based on soil characteristics: pH value, contents of clay, exchangeable potassium and humus. A comparison of measured and predicted values from Absalom's model is shown graphically. It has been found that Absalom's model might be carefully used for the prediction of (137)Cs in grass for specific regions.  相似文献   

18.
The activity concentrations of both natural (238U and 232Th chains and 40K) and anthropogenic (137Cs) radionuclides down along the soil profile have been determined in soil samples collected from inland and coastal areas of the La Plata River, located in the Northeastern region of the Province of Buenos Aires, Argentina. These studies were complemented with 57Fe Mössbauer spectroscopy characterization, pH, texture and organic carbon content measurements. From Mössbauer results, the sample compositions differ from one area to the other. Spectra from both soil samples are dominated by the Fe3+? paramagnetic signal. For soil samples from the coastal area, the ??-Fe2O3 contribution is lower, Fe3O4 was not detected, and the relative areas of each spectral contribution are nearly constant with depth. For samples from the inland area, the Fe3+? paramagnetic fraction increases up to 82%, mainly at the expense of the magnetically ordered phase. The main observed activity originates from the decay of 40K (540?C750 Bq/kg), followed by 238U (60?C92 Bq/kg) and 232Th (37?C46 Bq/kg) chains. The activity of 235U was in all the cases lower than the detection limit (LD?=?0.02 Bq/kg). The only determined anthropogenic nuclide was 137Cs, arising from the fallout of the Southern Hemisphere nuclear weapon tests. Three of the observed differences in the depth distributions can be described by the dispersion-convection model. A correlation between the natural nuclide activities and the Mössbauer relative fractions was found, whereas no correlation was found between the 137Cs profile and the relative fraction of Fe3O4 or with other iron species.  相似文献   

19.
In this paper, a vertical distribution of 137Cs in agricultural soil was investigated. 137Cs is an anthropogenic radioisotope which is strongly adsorbed in soil and can be used to study soil erosion. This paper presents some preliminary results of measurements of activity of 137Cs in soil in Bia?a and Odonów areas. In both areas, the upper part of the soil profile was cultivated. The experimental results show that the vertical distribution of 137Cs in agricultural soil is different from the vertical distribution of 137Cs in undisturbed soil. The 137Cs is more uniformly distributed in the cultivated soil layer than in an undisturbed site. Migration of 137Cs below plough depth is limited. These data show that the depth distribution of 137Cs in soil profiles for cultivated fields should be considered for precise determination of soil erosion.  相似文献   

20.
Cesium uptake in onion (from 0.3 mM CsCl solution traced with 137CsCl) has been examined. The highest uptake occurred at pH 4–5 and it decreased with increasing pH. The intensity of Cs translocation depended on acidity of the solution. For acidic solutions, translocation of cesium into bulbs and leaves was greater than in case of alkaline solutions, where most of the cesium remained in the roots. Addition of potassium into the solutions (millimolar K concentrations) inhibits Cs uptake. The potassium pH-influx/efflux characteristic does not coincide with the Cs uptake.  相似文献   

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