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1.
This article evaluates the health risk raised by exposure to naturally occurring radionuclides in soil around Khak-Sefid, Ramsar, Iran, which is an area of high natural background radiation. A high purity germanium detector was used to determine levels of radionuclides in soil samples and the cancer morbidity risk for a hypothetical resident farmer was evaluated using the RESidual RADioactivity (RESRAD) code. The average activity concentrations of 226Ra, 232Th, and 40K were found to be 13,201 ± 391, 27.9 ± 2.4, and 415.5 ± 16 Bq/kg, respectively. The maximum assessed cancer morbidity risks were calculated from external and internal exposure pathways as 4.73 × 10?2 and 3.40 × 10?2 for 226Ra, 1.41 × 10?4 and 7.88 × 10?5 for 232Th, and 1.3 × 10?4 and 4.233 × 10?4 for 40K. The RESRAD calculations also showed total cancer morbidity risks from external gamma and plant ingestion pathways were more important than from other exposure pathways. A sensitivity analysis was also performed to determine the input parameter values in the risk assessment process. In general, due to the high calculated risk of 226Ra compared with 232Th and 40K it can be the major source of concern for human heath in the study area. 相似文献
2.
《农业工程》2020,40(3):254-261
The activity concentration of 226Ra, 232Th and 40K were determined in clay samples collected from Tiruvannamalai district, Tamilnadu using gamma ray spectrometry. The determined activity concentration ranges from BDL to 16 Bq Kg−1, 18 to 192 Bq Kg−1, 288 to 901 Bq Kg−1 for 226Ra, 232Th and 40K respectively. The concentration of these radionuclides is compared with world average values. Radiological risk evaluation was done by calculating radium equivalent activity (Raeq), absorbed gamma dose rate (DR), annual effective dose rate (HR), annual gonadal dose equivalent (AGDE), criteria formula (CF), representative level index (RLI), activity utilization index (AUI), gamma index (Iγ), alpha index ((Iα), the external hazard (Hex) and internal hazard (Hin) due to internal exposure to radionuclides distributed in clay samples. Multivariate statistical techniques were used to study the relation between activity concentration and radiation hazards of clay samples. 相似文献
3.
Evseeva TI Geras'kin SA Belykh ES Maĭstrenko TA Vakhrusheva OM 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2012,52(2):187-197
The risk of an enhanced level of radionuclides of the uranium and thorium decay series in the environment for reference plant species (Pinus sylvestris and Vicia cracca) was assessed. 238U, 230Th, 226Ra, 210Po, 232Th and 228Th concentration factors for plants were found to be lower than one. The aboveground parts of Vicia cracca sampled from the area of the radium production waste storage mainly accumulated 22Ra, Pinus sylvestris branches--210Pb, 226Ra and 210Po. LOEDR calculated for the chromosome aberration frequency in both plant studies was 17-71 microGy/h. LOERD values for the reproductive capacity decrease in P. sylvestris and V. cracca were 17-71 microGy/h and 116-258 microGy/h, correspondingly. EDR10 for the chromosome aberration frequency in P. sylvestris and V. cracca were 148 and 347 microGy/h, that is, correspondingly, 255 and 708 times higher that background values. EDR10 for the plant reproductive capacity was 11-34 microGy/h, which 19-69 times increases the background values. 相似文献
4.
M. U. Khandaker Kh. Asaduzzaman S. M. Nawi A. R. Usman Y. M. Amin E. Daar D. A. Bradley H. Ahmed A. A. Okhunov 《PloS one》2015,10(6)
The environment of the Straits of Malacca receives pollution as a result of various industrial and anthropogenic sources, making systematic studies crucial in determining the prevailing water quality. Present study concerns concentrations of natural radionuclides and heavy metals in marine fish (Rastrelliger kanagurta) collected from the Straits of Malacca, since aquatic stock form an important source of the daily diet of the surrouding populace. Assessment was made of the concentrations of key indicator radionuclides (226Ra, 232Th, 40K) and heavy metals (As, Mn, Fe, Cr, Ni, Zn, Cu, Co, Sr, Al, Hg and Pb) together with various radiation indices linked to the consumption of seafish. The annual effective dose for all detected radionuclides for all study locations has been found to be within UNSCEAR acceptable limits as has the associated life-time cancer risk. The overall contamination of the sampled fish from heavy metals was also found to be within limits of tolerance. 相似文献
5.
Khandoker Asaduzzaman Farhana Mannan Mayeen Uddin Khandaker Mohideen Salihu Farook Aeman Elkezza Yusoff Bin Mohd Amin Sailesh Sharma Hasan Bin Abu Kassim 《PloS one》2015,10(10)
The concentrations of primordial radionuclides (226Ra, 232Th and 40K) in commonly used building materials (brick, cement and sand), the raw materials of cement and the by-products of coal-fired power plants (fly ash) collected from various manufacturers and suppliers in Bangladesh were determined via gamma-ray spectrometry using an HPGe detector. The results showed that the mean concentrations of 226Ra, 232Th and 40K in all studied samples slightly exceeded the typical world average values of 50 Bq kg−1, 50 Bq kg−1 and 500 Bq kg−1, respectively. The activity concentrations (especially 226Ra) of fly-ash-containing cement in this study were found to be higher than those of fly-ash-free cement. To evaluate the potential radiological risk to individuals associated with these building materials, various radiological hazard indicators were calculated. The radium equivalent activity values for all samples were found to be lower than the recommended limit for building materials of 370 Bq kg-1, with the exception of the fly ash. For most samples, the values of the alpha index and the radiological hazard (external and internal) indices were found to be within the safe limit of 1. The mean indoor absorbed dose rate was observed to be higher than the population-weighted world average of 84 nGy h–1, and the corresponding annual effective dose for most samples fell below the recommended upper dose limit of 1 mSv y–1. For all investigated materials, the values of the gamma index were found to be greater than 0.5 but less than 1, indicating that the gamma dose contribution from the studied building materials exceeds the exemption dose criterion of 0.3 mSv y-1 but complies with the upper dose principle of 1 mSv y−1. 相似文献
6.
Zinka B Kandlbinder R Schupfner R Haas G Wolfbeis OS Graw M 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2012,69(2):147-157
Reliable determination of time since death in human skeletons or single bones often is limited by methodically difficulties. Determination of the specific activity ratio of natural radionuclides, in particular of 232Th (Thorium), 228Th and 228Ra (Radium) seems to be a new appropriate method to calculate the post mortem interval. These radionuclides are incorporated by any human being, mainly from food. So with an individual's death the uptake of radionuclides ends. But the decay of 232Th produces 228Ra and 228Th due to its decay series, whereas 228Th is continuously built up in the human's bones. Thus, it can be concluded that in all deceased humans at different times after death different activity ratios of 228Th to 228Ra will develop in bone. According to this fact it should be possible to calculate time since death of an individual by first analysing the specific activities of 228Th and 228Ra in bones of deceased and then determining the 228Th/228Ra activity ratio, which can be assigned to a certain post-mortem interval. 相似文献
7.
There is a scarcity of data on transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates for
use in the assessment of radiation exposure. Although mosses and lichens have been extensively used in biomonitoring programs,
the data on transfer of radionuclides to these species are limited, particularly for natural radionuclides. To enhance the
available data, activity concentrations of 137Cs, 226Ra and 228Ra were measured in ants, mosses and lichens and corresponding undisturbed soil collected from semi-natural ecosystems in
Serbia and Montenegro and biota/soil concentration ratios (CR) calculated. Since the majority of internal dose to biota is
expected to come from 40K, the activity concentrations of this radionuclide were also determined. The mean CR values for 137Cs, 226Ra and 228Ra in ants analyzed in this study were found to be 0.02, 0.06 and 0.02, respectively. The mean CR values of radionuclides
in mosses were found to be 2.84 for 137Cs, 0.19 for 226Ra and 0.16 for 228Ra, while those in lichens were found to be 1.08 for 137Cs, 0.15 for 226Ra and 0.13 for 228Ra. The CR values obtained in this study were compared with default CR values used in the ERICA Tool database and also with
those reported in other studies. 相似文献
8.
One of the three goals of the United Nations for sustainable food security is to ensure that all people have access to sufficient,
nutritionally adequate, and safe food. Decades of tin mining in the Bitsichi area of the Jos Plateau, Nigeria, have left a
legacy of polluted water supplies, impoverished agricultural land, and soil containing abnormally high levels of naturally
occurring radioactive elements. In order to ascertain the radiological food safety of the population, different crops that
constitute the major food nutritive requirements were collected directly across farmlands in the area. The activity concentrations
of 226Ra, 228Th, and 40K were determined in the food and soil samples using γ-ray spectrometry. Additionally, in situ gamma dose rate measurements
were performed on the farms using a pre-calibrated survey meter. The corresponding activity concentrations in the food crops
ranged from below detection limit (BDL) to 684.5 Bq kg−1 for 40K, from BDL to 83.5 Bq kg−1 for 226Ra, and from BDL to 89.8 Bq kg−1 for 228Th. Activity concentrations of these radionuclides were found to be lower in cereals than in tubers and vegetables. As for
the soil samples, activity concentrations of these radionuclides varied from BDL to 166.4 Bq kg−1, from 10.9 to 470.6 Bq kg−1, and from 122.7 to 2,189.5 Bq kg−1 for 40K, 226Ra, and 228Th, respectively. Average external gamma dose rates were found to vary across the farms from 0.50 ± 0.01 to 1.47 ± 0.04 μSv h−1. Due to past mining activities, the soil radioactivity in the area has been modified and the concentration level of the investigated
natural radionuclides in the food crops has also been enhanced. However, the values obtained suggest that the dose from intake
of these radionuclides by the food crops is low and that harmful health effects are not expected. 相似文献
9.
Omeje M. Adewoyin O. Olusegun Emmanuel S. Joel Ehi-Eromosele C. O Emenike C. PraiseGod Usikalu M. R. 《人类与生态风险评估》2018,24(8):2036-2053
Elevated radioactivity levels of 226Ra, 232Th, and 40K in building materials were measured using gamma-ray spectrometry and their associated lifetime cancer risks were also determined. The mean activity concentrations of 226Ra, 232Th, and 40K are 45.72 ± 0.55, 65.90 ± 8.89, and 487.32 ± 15.20 Bq kg?1, respectively. Statistically, the principal component (PC) analysis indicates that higher loadings were recorded in Principal Component One (PC1) with large contribution from 232Th and 40K. The leverage studies indicate that BN Ceramics (BNC) contributes more to the loadings in PC1 followed by Golden Crown Ceramic (GCC) sample. The mean values of 0.399 mSv y?1 do not surpass the world average value of 0.7 mSv y?1. The mean gamma index from the measured samples is 0.644, whereas a mean value of 0.271 for alpha index is noted in the samples. The activity utilization index (AUI) from the samples satisfied the AUI <2, which corresponded with the annual effective dose of <0.3 mSv y?1, except interlock Site 2 and Gomez Spain tiles. Significantly, the mean value of excess lifetime cancer risk of 0.0014 is slightly lower than the world average value of 0.29 × 10?3. 相似文献
10.
Noskova LM Shuktomova II 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2010,50(6):642-648
The results of studies on uranium and radium distribution in soil and vegetation at the territory contaminated by wastes of radium plant in 1930-1950 are presented. Specific activities of 226Ra and 238U in soil varied as 0.01-200 and 0.004-7.58 Bq/g per ash respectively. The radionuclides are mainly concentrated in the upper layer of soil profile. In the vegetation concentrations of 226Ra and 238U varied as 0.64-132 0.001-0.02 Bq/g per ash respectively. Among the woody species studied, Betula pubescens and Sorbus aucuparia are characterized by the highest absorption of radionuclides. For all plants studied a negative linear dependence is shown between logarithm of TF (TF = [226Ra, 238U in plant, Bq/g per ash]/[226Ra, 238U in soil, Bq/g per ash]) and logarithm of 226Ra and 238U concentrations in soil. The findings obtained can be used in modeling of biological absorption in radioecological investigations. 相似文献
11.
Lake Manzala is one of the Deltaic Mediterranean lakes in Egypt. It comprises over 1000 islands of various sizes, the vegetation of which is halophytic. Seven community types are described, dominated by: Phragmites australis, Juncus acutus, J. rigidus, Arthrocnemum macrostachyum, Atriplex portulacoides, Halocnemum strobilaceum and Zygophyllum aegyptium. Each of these communities has been analysed and its habitat described and discussed. 相似文献
12.
Nazanin Haghighat Parviz Abdolmaleki Faezeh Ghanati Mehrdad Behmanesh Atefeh Payez 《Journal of plant physiology》2014
The effects of a static magnetic field (SMF) and high natural radioactivity (HR) on catalase and MAPK genes in Vicia faba were investigated. Soil samples with high natural radioactivity were collected from Ramsar in north Iran where the annual radiation absorbed dose from background radiation is higher than 20 mSv/year. The specific activity of the radionuclides of 232Th, 236Ra, and 40K was measured using gamma spectrometry. The seeds were planted either in the soil with high natural radioactivity or in the control soils and were then exposed to a SMF of 30 mT for 8 days; 8 h/day. Levels of expression of catalase and MAPK genes, catalase activity and H2O2 content were evaluated. The results demonstrated significant differences in the expression of catalase and MAPK genes in SMF- and HR-treated plants compared to the controls. An increase in catalase activity was accompanied by increased expression of its gene and accumulation of H2O2. Relative expression of the MAPK gene in treated plants, however, was lower than those of the controls. The results suggest that the response of V. faba plants to SMF and HR may be mediated by modification of catalase and MAPK. 相似文献
13.
Evseeva TI Belykh ES Maĭstrenko TA Geras'kin SA Taskaev AI Vakhrusheva OM 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2012,52(1):103-112
Cartographical investigations of the territory of radium production waste storage has shown some changes in lateral differentiation of radionuclides of uranium and thorium decay series to occur during 27 years (1981-2008). Those changes are caused mostly by flat denudation typical for fluvial terrace. At present radionuclides of uranium and thorium decay series are concentrated mostly in flood lands and relief depressions. At the same time, decrease in the radionuclide activity concentration in 0-20 cm soil layer is observed with changes in lateral distribution. Total stocks of 226Ra, 210Pb and 210Po within catena soils studied in the northern and southern parts of the waste storage decreased 3-6 times, 238U - 2 times, and did not significantly change in case of 232Th during 27 years. Nonetheless, most of the samples studied are referred to radioactive waste both according to Russian standards (SPORO-2002) and IAEA safety norms (IAEA, 2004). 相似文献
14.
Manakhov D. V. Emelyanov A. M. Karpukhin M. M. Lipatov D. N. Agapkina G. I. Mamikhin S. V. 《Biology Bulletin》2019,46(12):1671-1678
Biology Bulletin - A comparison of sequential extraction methods proposed by F.I. Pavlotskaya [1, 2] and A. Tessier [3] for fractionation of technogenic (137Cs and 90Sr) and natural (226Ra, 232Th,... 相似文献
15.
Vasil'eva AN Kruglov SV Koz'min GV Latynova NE Kvasnikova IuV Vaĭzer VI Starkov OV 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2008,48(1):102-109
The objects of researches are the soil and wild vegetation in the region of the radioactive waste storage situation. In result of monitoring it was recognized 137Cs unlike 90Sr did not spread out of storage territory in spite of trench destruction and migration of radionuclides with surface and ground waters. The forms of 137Cs, 90Sr and natural radionuclide 226Ra in soils and coefficients of 90Sr accumulation for the different kinds of plants growing at the territory of storage and 50-m zone around it were researched. The low specific activities of mobile forms of 90Sr were recognized for samples of soils selected from lowland by the terrace. The considerable differences were found for specific activities of radionuclides for different soil layers. Essential irregularity of soil surface and vegetation contamination at the test points disposed at a short distances from each other also was found. The interpretation of obtained results is presented. 相似文献
16.
Summary The natural radionuclide content of mineral phosphate fertilizers has been determined gammaspectrometrically. The investigations comprised ca. 70% of the mineral phosphate fertilizers authorized and used in the Federal Republic of Germany (FRG). At maximum, we found specific activities of 62 nCi Unat/kg, 23 nCi226Ra/kg, 1.6 nCi Thnat/kg and 262 nCi40K/kg. The mean values, weighted by the percentual agricultural consumption of the main phosphate fertilizer groups in 1973/74 and related to the phosphate content, amounted to 58, 40, 2, and 584 nCi/kg P2O5 for Unat,226Ra, Thnat, and40K respectively. This resulted in an annual distribution due to phosphate fertilizing of about 3.9 µCi Unat, 2.7 µCi226Ra, 0.1 µCi Thnat, and 39.9 µCi40K per ha of arable or pasture land in 1973/74 on the average. From these values the air dose rates over agricultural areas have been estimated under extreme conservative assumptions resulting in an additional external exposure of members of the population of 0.02 mrd/a on the average and 0.4 mrd/a in the region of highest phosphate fertilizing intensity. If it is assumed that radium contained in phosphate fertilizers were completely accumulated in the soils during the last 80 years, this value would be raised to 0.3 mrd/a on the average. The occupational external radiation exposure due to natural radionuclides contained in phosphate fertilizers was estimated to be 0.1 mrd/a on the average and 2.3 mrd/a at maximum for persons working in agriculture. These estimates show that natural radionuclides in phosphate fertilizers contribute but very little to the mean terrestrial radiation exposure of the population which is 50 to 55 mrd/a in Germany. Only for the small group of persons working in fertilizer production plants or storehouses a significant increase of the external radiation exposure has to be expected which could reach a doubling of the mean natural exposure value.Dedicated to Prof. Dr. H. Muth on the occasion on his 60th birthday 相似文献
17.
几丁质酶基因转化亚麻、红豆草、骆驼刺的同工酶研究 总被引:5,自引:0,他引:5
以亚麻、红豆草、骆驼刺的下胚轴为外植体,用含几丁质酶RC24基因的根瘤农杆菌LBA4404进行转化。对3种植物转化植株叶片及对照植株叶片的愈伤组织的过氧化物酶及酯酶同工酶分析表明,转基因植株叶片愈伤组织的同工酶谱与对照系相比具有明显的差异,由此推测转化系愈伤组织中可能存在变化了的基因产物,并认为导入的外源几丁质酶基因可能引起了转化材料的遗传变异。 相似文献
18.
The abundance and structure of the foraminifera community have been investigated. The role of agglutinating and secreting species in bottom sediments of the deep trenches of the Kara Sea has been studied. It has been found that the abundance and dominance of the agglutinated foraminifera Saccorhiza ramosa depend on the depth of the sea and are related to the genetic type of origin of such sediments. A correlation has been revealed between the distribution of S. ramosa and the concentrations of natural radionuclides (226Ra, 232Th, and 210Pb) in bottom sediments. The degree of dominance of S. ramosa in the community of benthic foraminifera increases along with natural radioactivity. 相似文献
19.
Concentrations of some radionuclides, including137Cs, in desert truffles in Kuwait were studied and compared with similar samples from other countries in the Middle East, namely
Iran, Egypt, and Tunisia. In addition, sand samples from Kuwait were assayed to calculate the transfer factor of the radionuclides
under consideration. The measured concentrations of40K,226Ra, and137Cs show that137Cs is much higher in Egyptian samples, whereas40K is much lower in samples from Tunisia. The average effective dose equivalent calculated for the Kuwaiti population according
to their diet habits was found to be in the range 0.14-0.23 ΜSv/a. The results are compared with values from other countries. 相似文献
20.
Aslı Kurnaz Muazzez Gezelge Aybaba Hançerlioğulları M. Atıf Çetiner Şeref Turhan 《人类与生态风险评估》2016,22(6):1375-1385
The activity concentrations of radionuclides in grape molasses soil samples collected from Zile (Tokat) plain in the Central Black Sea region of Turkey were measured by using gamma spectrometer with a NaI(Tl) detector. Also, the concentrations of 222Rn in soil samples and air were estimated essentially taking the activity concentrations of 226Ra measured in soil samples. Grape molasses soil samples with calcium carbonate content are used for sedimentation for making molasses in this region. The average activity concentrations of 232Th, 226Ra, 40K, and 137Cs were found as 62 ± 2, 68 ± 3, 479 ± 35, and 8.0 ± 0.3 Bq kg?1, respectively. The average concentrations of 222Rn in soil samples and air were estimated to be 50 kBq m?3 and 144 Bq m?3. From the activity concentrations, absorbed gamma dose rate in outdoor air (D), annual effective dose from external exposure (EE), annual effective dose from inhalation of radon (EI), and excess lifetime cancer risk (ELCR) were estimated in order to assess radiological risks. The average values of D, EE, EI, and ELCR were found to be 90 nGy h?1, 110 μSv y?1, 1360 μSv y?1, and 4 × 10?4, respectively. 相似文献