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1.
Kazuya Tanaka Hokuto Iwatani Aya Sakaguchi Yoshio Takahashi Yuichi Onda 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2007-2014
We analyzed fresh and dead leaves collected in forests in Fukushima after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, using autoradiography. Both fresh and dead leaves of Cryptomeria japonica were contaminated by radionuclides (134Cs and 137Cs). Contamination of the fresh leaves was possibly attributed to interception of radionuclides by tree canopies, whereas the dead leaves indicated the direct deposition of radionuclides by fallout and/or washout of radionuclides intercepted by tree canopies. Translocation of radiocesium from a contaminated branch to new leaves growing after the FDNPP accident was not clearly observed, although transfer of radiocesium from leaf parts to male flowers occurred. Fallen leaves of Quercus serrata, which started growing after the FDNPP accident, did not show radioactivity, indicating that significant amounts of translocation from other parts to new leaves did not occur. Fallen leaves of Q. serrata collected from a litter showed hot spots originating from direct fallout. Needles of Pinus densiflora were also contaminated by fallout. Leaching with pure water removed soluble fractions of radiocesium and hot particles from the surface of the contaminated leaves, but significant amounts of radioactivity remained. This means that foliar absorption occurred in both fresh and dead leaves. Further leaching experiments using surfactant and acetone could not remove the remaining radiocesium from the leaves. The leaching experiments indicate that radiocesium in the contaminated leaves is strongly fixed in leaf tissues and is not readily released unless leaf tissues are decomposed. 相似文献
2.
P. P. Povinec I. Sýkora M. Gera K. Holý L. Brest’áková A. Kováčik 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1171-1176
Results of forward and backward modeling of air mass transport from Fukushima Daiichi nuclear power plant to Slovakia were compared with aerosol radioactivity measurements. Several radionuclide maxima (131I, 134Cs and 137Cs) were observed in the Bratislava ground-level air in March–April 2011. The 131I/137Cs activity ratio records showed the presence of two different fresh air masses in the Bratislava air, supported by simulations of forward and backward trajectories between Fukushima and Bratislava. 相似文献
3.
Weihua Zhang Judah Friese Kurt Ungar 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):69-73
In this study, soil samples were collected at Canadian embassy in Tokyo (about 300 km from Fukushima) on 23 March and 23 May of 2011 for purposes of estimating concentrations of radionuclides in fallout, the total fallout inventory, the depth distribution of radionuclide of interest and the elevated ambient gamma dose-rate at this limited location. Some fission products and actinides were analyzed using gamma-ray spectrometry, alpha spectrometry and liquid scintillation counting. The elevated activity concentration levels of 131I, 132I, 134Cs, 137Cs, 136Cs, 132Te, 129mTe, 129Te, 140Ba and 140La were measured by the gamma-ray spectrometer in the first sample collected on 23 March. Two months after the accident, the 134Cs and 137Cs became only detectable nuclides. A mass relaxation depth of 3.0 g/cm2 was determined by the activities on the depth distribution of 137Cs in a soil core. The total fallout inventory was thus calculated as 225 kBq/m2 on March sampling date and 25 kBq/m2 on May sampling date. The ambient gamma dose-rates in the sampling area estimated by the fallout fission products inventory and 137Cs depth distribution ranged from 184 to 38 nGy/h. There was no detectable americium or plutonium in the soil samples by alpha spectrometry. Although 90Sr or 89Sr were detected supposedly as a result of this accident, it was less than the detection limit, which was about 0.4 Bq/kg in the soil samples. 相似文献
4.
Ryuta Hazama Akihito Matsushima 《Journal of Radioanalytical and Nuclear Chemistry》2013,297(3):469-475
Fallout with rain from the Fukushima reactor accident was monitored for about two months in Higashi-Hiroshima City, Hiroshima, Japan, from March 20 to May 23, 2011. Gamma-ray (γ-ray) spectra measured using a low background HPGe spectrometer showed clear evidence of fission products—131I, 137Cs, and 134Cs. The 131I was observed on March 27 and April 8, while 137Cs and 134Cs were observed on March 27, April 18, and April 22. The 131I, 137Cs, and 134Cs activity concentrations in rainwater collected in Hiroshima reached 0.44 ± 0.09 on April 8, 0.17 ± 0.01 on April 18, and 0.15 ± 0.01 Bq/L on April 18, 2011, respectively. These activity levels were compared with global results collected from the Northern Hemisphere. Several samples of rainwater that were collected in Chiba (Kashiwa) on March 21, April 11, and May 12; Tokyo (Nerima) on March 21 and April 11; Osaka (Hirano) on April 8; Nara (Kitakatsuragi) on April 9; and Fukushima (Fukushima) on April 19, were also measured by our spectrometer and compared. Among these samples of rainwater collected at different locations in Japan, the one collected at Kashiwa City, Chiba Prefecture, on March 21 showed the highest activity concentrations of 6072 ± 1, 632 ± 4, 766 ± 3, 637 ± 1, 97.6 ± 0.8, and 752 ± 2 Bq/L for 131I, 132I, 132Te, 134Cs, 136Cs, and 137Cs, respectively. The health risks due to these high activity levels were considered in terms of several regulations. The ratio of the activites for the isotopes 131I to 137Cs and 134Cs to 137Cs were compared with the other measurements and discussed. 相似文献
5.
Relationship between particle size and radiocesium in fluvial suspended sediment related to the Fukushima Daiichi Nuclear Power Plant accident 总被引:1,自引:0,他引:1
Kazuya Tanaka Hokuto Iwatani Aya Sakaguchi Yoshio Takahashi Yuichi Onda 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(2):607-613
We collected fluvial suspended sediments in Fukushima after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident and analyzed the 137Cs concentration in bulk and size-fractioned samples to investigate the particle-size-dependent distribution of radiocesium. The 137Cs concentration in bulk suspended sediments decreased from August to December 2011, possibly reflecting a decrease of radiocesium concentration in its source materials. Smaller particles had higher radiocesium concentrations, reflecting larger specific surface areas. Silt- and sand-size fractions occupied more than 95 % of the total 137Cs in the suspended sediments. The contribution of clay-size fractions, which had the highest 137Cs concentration, was quite small because of their low frequency. A line of the data showed that the particle size distribution of radiocesium was essential to evaluate the migration and distribution of radiocesium in river systems where radiocesium is mainly present as particulate form after the FDNPP accident. 相似文献
6.
A. Ioannidou E. M. Manolopoulou S. Stoulos E. Vagena C. Papastefanou M. L. Bonardi L. Gini S. Manenti F. Groppi 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):855-860
131I, 137Cs and 134Cs were observed in environmental samples in Milano (40°N), Italy and Thessaloniki (45°N), Greece, soon after the nuclear accident in Fukushima, Japan. The radionuclide concentrations were determined and studied as a function of time. In Thessaloniki the 131I in air was observed for the first time on March 24, 2011. In Milano, the first evidence of Fukushima fallout has been confirmed with 131I and 137Cs measured in wet precipitation collected 2 days later. The maximum 131I activity concentration in air of 467 ± 25 μBq m?3, observed in Milano on April 3–4, 2011, was almost similar to the highest value of 497 ± 53 μBq m?3 observed in Thessaloniki. The 134Cs/137Cs activity ratio values in air were around 1 in both regions. Soil, grass and milk samples were contaminated with 131I and 137Cs at a low level. Finally, a dose assessment for these two areas showed clearly that the detected activities in all environmental samples were far below levels of concern. 相似文献
7.
Sang-Han Lee Dong-Hye Heo Han-Byeol Kang Pil-Jae Oh Jong-Man Lee Tae-Soon Park K. B. Lee J. S. Oh Jung-Ki Suh 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(2):727-731
Radionuclides such as 131I, 134Cs, 137Cs, and 239,240Pu in Korean rainwater have been analyzed by Korea Research Institute of Standards and Science (KRISS) since the Fukushima nuclear power plant accident in March 2011 to investigate the activity level, distribution pattern, and temporal variation and to assess the radiation dose the public is exposed to. The concentration of 131I in the Korean rainwater samples varied between 0.033 (minimum detectable activity; MDA) and 1.30 Bq kg?1 and the concentrations tended to decrease exponentially with time. The concentrations of 134Cs and 137Cs in rainwater ranged from 0.01 to 334 ± 74 and 0.29 ± 0.01 to 276 ± 1 mBq kg?1, respectively. The mean activity ratio of 137Cs/134Cs in the rainwater samples collected from April 18 to May 12 was estimated to be 0.44 ± 0.21, and this value is lower than that (ca. 1) observed in Fukushima, Japan, when there was an escape from the nuclear reactors. When an attempt was made to analyze Pu isotopes in rainwater samples, no Pu isotopes were detected above the MDA in any of the rainwater samples. Although the locations investigated were different from Asia to Europe, the concentrations of 131I, 134Cs and 137Cs in the rainwater are comparable, which suggests a global contamination of 131I, 134Cs, and 137Cs occurred because of the Fukushima nuclear power plant accident. 相似文献
8.
A nondestructive analytical method based on autoradiography and gamma spectrometry was developed to perform activity distribution analysis for particulate samples. This was applied to aerosols collected in Fukushima Japan, 40 km north of the Daiichi nuclear power plant for a 6 week period beginning shortly after the March 2011 tsunami. For an activity distribution of 990 “hot particles” from a small filter area, the hottest particle was nearly one Bq 137+134Cs but most of the activity in the filter was produced by particles having <50 mBq each. 134Cs/137Cs activity ratios corrected to March 20, 2011 ranged from 0.68 (u c = 28 %) to 1.3 (u c = 15 %). The average ratio for a large quantity of particles was 0.92 (u c = 4 %). Virtually all activity collected was beta and not alpha, suggesting little if any direct fuel debris was present at this site and time. These findings are expected to assist with separate efforts to better understand the emission events, radionuclide transport and potential environmental or biological uptake. The methods should be applicable to general environmental, radiotoxicological and similar studies for which activity distribution and particle chemistry are of importance. 相似文献
9.
K. Ioannides K. Stamoulis C. Papachristodoulou 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(2):1207-1213
The impact of the Fukushima nuclear accident in north–western Greece was assessed through an environmental monitoring programme activated by the Nuclear Physics Laboratory of the University of Ioannina. Measurements of 131I were carried out in atmospheric particulate, ovine milk and grass samples. In daily aerosol samplings, radioiodine was first detected on March 25–26, 2011 and reached maximum levels, up to 294 μBq m?3, between April 2 and April 4, 2011. In ovine milk samples, 131I concentrations ranged from 2.0 to 2.7 Bq L?1 between April 2 and April 6, 2011, while an average activity of 2.7 Bq kg?1 was measured in grass samples on April 4, 2011. The 134,137Cs isotopes were below detection limits in all samples and could only be determined in the air, by analysis of multiple daily filters. A maximum average activity concentration of 137Cs amounting to 24 μBq m?3 was measured during the period from April 5 to April 9, 2011, with the 134Cs/137Cs activity ratio being close to unity. Activity concentrations were consistent with measurements conducted in other parts of the country and were well below those reported in May 1986 after the Chernobyl accident. The committed effective dose to the whole body and to the thyroid gland from inhalation of 131I was estimated for the adult and infant population and was found to be of no concern for the public health. 相似文献
10.
Y. Inomata M. Aoyama T. Tsubono D. Tsumune Y. Kumamoto H. Nagai T. Yamagata M. Kajino Y. T. Tanaka T. T. Sekiyama E. Oka M. Yamada 《Journal of Radioanalytical and Nuclear Chemistry》2018,318(3):1587-1596
Distributions of radiocaesium (134Cs and 137Cs) derived from the Tokyo Electric Power Company (TEPCO) Fukushima Dai-ichi Nuclear Power Plant (FNPP1) accident in the North Pacific Ocean in the summer of 2012 were investigated. We have estimated the radiocaesium inventory in the surface layer using the optimal interpolation analysis and the subducted amount into the central mode water (CMW) by using vertical profiles of FNPP1-134Cs and mass balance analysis as the first approach. The inventory of the 134Cs in the surface layer in the North Pacific Ocean in August–December 2012 was estimated at 5.1?±?0.9 PBq on 1 October 2012, which corresponds to 8.6?±?1.5 PBq when it was decay corrected to the date of the FNPP1 accident, 11 March 2011. It was revealed that 56?±?10% of the released 134Cs into the North Pacific Ocean, which was estimated at 15.3?±?2.6 PBq, transported eastward in the surface layer in 2012. The amount of 134Cs subducted in the CMW was estimated to be 2.5?±?0.9 PBq based on the mass balance among the three domains of the surface layer, subtropical mode water, and CMW. 相似文献
11.
Removal of radiocesium from food by processing is of great concern following the accident of TEPCO’s Fukushima Daiichi Nuclear Power Plant accident. To provide more Cs removal rates, we studied the applicability of K data using edible plant samples. Values were compared for 137Cs and 40K of the food processing retention factors, F r (total activity in processed food/total activity in raw food), and they were found to be close to the 1:1 line and highly correlated (R = 0.96, p < 0.001). Thus, K can be an analogue to estimate radiocesium removal rates by food processing of vegetables. Using the literature K values, we calculated the K removal rates (%), that is, (1 ? F r) × 100, for ten vegetable types to provide potential Cs removal rates. The average percent of K removal were as follows: dried pulses, 33; fresh pulses, 15; leafy vegetables, 52; fruit vegetables, 7; flower vegetables, 44: root crops, 18; tubers, 16; ferns, 93: mushrooms, 32; and others, 30. 相似文献
12.
Michael E. Kitto Traci A. Menia Douglas K. Haines Shaun E. Beach Clayton J. Bradt Eileen M. Fielman Umme-Farzana Syed Thomas M. Semkow Abdul Bari A. J. Khan 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):49-56
An air-sampling network that operates continuously as part of New York State’s environmental surveillance program collected radionuclides emitted as a result of the Fukushima nuclear accident. Samples were collected, typically for 7 days each, by drawing ~600 m3 of air through a particulate-collecting filter followed in series by a canister containing activated charcoal. Additional air sampling was implemented at ~3-day intervals at two locations. Gamma-ray spectroscopy was used to confirm the detection of 131I, 137Cs, 134Cs, and 7Be in the particulate phase at all sites, with maximum concentrations near 1,260, 160, 160, and 5,200 μBq/m3, respectively. Gas-phase 131I, collected on activated charcoal, exhibited a maximum concentration of 3,400 μBq/m3 at the sites. Assessment of radionuclide levels in the air samples suggests that there were minimal health impacts from the airborne radionuclides as the activities contributed an insignificant amount to the annual human dose. 相似文献
13.
S. M. Pike K. O. Buesseler C. F. Breier H. Dulaiova K. Stastna F. Sebesta 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):369-374
The March 2011 earthquake off the Japanese coast and subsequent tsunami that devastated the Fukushima Dai-Ichi nuclear power plant resulted in the largest accidental release of cesium 137 and 134 to the oceans. Seawater samples were collected in June 2011 from 30 to 600 km off the coast of Japan as part of initial mapping of the spread of contamination in the ocean. Cesium was extracted from unfiltered and filtered (<1.0 μm) seawater using an absorber based upon an organic polymer polyacrylonitrile (PAN) containing ammonium molybdophosphate (AMP) Sebesta and Stefula (J Radioanal Nucl Chem 140:15–21, 1990). The AMP-PAN resin can be counted directly using gamma spectroscopy for 134Cs and 137Cs. Stable 133Cs was added to evaluate extraction efficiency and quantified by ICP-MS. Our 5 mL AMP-PAN resin column was on average 95 % efficient in the removal of cesium from 20 L samples at an average flow rate of 35 mL min?1. Measured activities of 134Cs and 137Cs ranged from a few Bq m?3 to >300 Bq m?3. The extraction column can be adapted to different sample volumes and easily used in the field. 相似文献
14.
S. J. Tumey T. P. Guilderson T. A. Brown T. Broek K. O. Buesseler 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(2):957-962
We present an initial characterization of the input of 129I into the Pacific Ocean resulting from the 2011 Fukushima nuclear accident. This characterization is based primarily on 129I measurements on samples collected from a research cruise conducted in waters off the eastern coast of Japan in June 2011. These measurements were compared with samples intended to reflect pre-Fukushima background that were collected during a May 2011 transect of the Pacific by a commercial container vessel. In surface waters, we observed peak 129I concentrations of ~300 μBq/m3 which represents an elevation of nearly three orders of magnitude compared to pre-Fukushima backgrounds. We coupled our 129I results with 137Cs measurements from the same cruise and derived an average 129I/137Cs activity ratio of 0.442 × 10?6 for the effluent from Fukushima. Finally, we present 129I depth profiles from five stations from this cruise which form the basis for future studies of ocean transport and mixing process as well as estimations of the total budget of 129I released into the Pacific. 相似文献
15.
Jian Zheng Keiko Tagami Shigeo Uchida 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):171-175
After the nuclear accident at TEPCO’s Fukushima Dai-ichi power station in March, hydrogen explosions and reactor building
explosion resulted in releases of radionuclides in the environment. Severe radioactive cesium and iodine contaminations have
been observed in fallout deposition samples and soils in the East Japan. Radioactive cesium, iodine, uranium, and transuranic
radionuclides were set as the monitoring targets in food safety tests. However, so far, only radioactive cesium and iodine
were daily measured and reported by the Ministry of Health, Labour, and Welfare. The tedious and time consuming conventional
alpha spectrometric method hampered the emergency monitoring U contamination in foods. In this work, we propose a simple and
rapid analytical method for 238U and 235U/238U isotope ratio analysis in fresh vegetables. This method was applied to the emergency monitoring of radioactive contamination
after the nuclear accident at TEPCO’s Fukushima Dai-ichi power station. The results showed no U contamination in fresh vegetables
collected in Chiba and Ibaraki prefectures in April and May, 2011. 相似文献
16.
R. K. Singhal H. Basu A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1345-1351
In case of natural catastrophic nuclear accident scenario like Daiichi Nuclear Power Plant (NPP) Fukushima, Japan (11 March 2011) and industrial nuclear accidents like Chernobyl, USSR (March 1986), thousands of curies of activity goes in the public domain and contaminate the drinking water system in the area around the accidental zone. In view of this there is a need to evolve methodology for decontamination of the drinking water without compromising the drinking water quality. During this work humic coated colloidal suspension of geothite(α-FeO(OH)) followed by ultrafiltration were used to decontaminate the water having 239+240Pu and 241Am in the concentration range of 10–100 Bq L?1. Polydispersive colloids of goethite were generated by controlled oxidation of FeSO4 in the presence of NaOH. Size characterization, morphology and elemental profiling of goethite suspension and their aggregation with increase in the concentration of humic acid was studied by using dynamic light scattering and scanning electron microscope hyphenated with energy dispersive spectrometry. Experimental results clearly indicate preferential association of Pu and Am with goethite suspension dominated with 30 nm colloids. The impact of humus material on selectivity of Pu and Am by goethite was studied in the concentration range of 10–100 μg mL?1 of humic acid. This selectivity is further enhanced linearly with the increase in concentration humic acid from 10 to 60 μg mL?1 and thereafter it remains constant. Goethite suspension having a coating of 60 μg mL?1 of humic acid was successfully utilized to decontaminate the water. Goethite suspension was separated from the groundwater using Ultra filtration cell with membrane having 500 NMWL (nominal molecular weight limit). 相似文献
17.
Xianglei Mao George C.-Y. Chan Inhee Choi Vassilia Zorba Richard E. Russo 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):121-126
Radionuclide concentrations in wharf roaches inhabiting coastal areas of Honshu, Japan, were investigated in October 2011 and June 2012. Relative high concentrations of 110mAg (2.1–127 Bq kg-wet?1), 134Cs (2.6–61 Bq kg-wet?1), and 137Cs (3.5–92 Bq kg-wet?1) were detected in specimens from the eastern Honshu areas. Significantly lower 137Cs concentrations (0.7–1.6 Bq kg-wet?1) were detected in specimens from western and northern Honshu. The decay-corrected 137Cs concentration was significantly inversely correlated with the distance from the Fukushima Dai-ichi Nuclear Power Plant. Thus, wharf roach may serve as a good bioindicator for monitoring radioactive contamination of its habitats. 相似文献
18.
Radioactive cesium deposition on rice,wheat, peach tree and soil after nuclear accident in Fukushima
We present how radioactive Cs was deposited on wheat, rice, peach tree and soil after nuclear accident in Fukushima. The deposition of radioactive Cs was found as spots at the surface of the leaves, branch or trunk of the trees, as well as in soil using one of the imaging method, autoradiography. The deposited radioactive Cs was not easily washed out, even with the treatment of acid solution. When the wheat was harvested 2 months after the accident, high radioactivity of Cs was found only on the leaves developed and expanded at the time of the accident. In the case of the rice grain, most of the radioactivity was found in bran and the radioactivity was drastically reduced in milled rice. Most of the radioactive Cs accumulation in rice plants was estimated from the absorption of the Cs ion dissolved in water, rather than Cs adsorbed in soil. 相似文献
19.
Michio Aoyama Daisuke Tsumune Yasunori Hamajima 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):535-539
Impact of the TEPCO Fukushima-Daiichi NPP accident, FNPP1, to the North Pacific Ocean occurred through two pathways, namely direct release and atmospheric deposition to wide ocean surface. We collected more than 100 seawater samples in the North Pacific Ocean in April and May 2011 by seven commercial ships as VOS. Since the sample volume was 2 l each, we measured radiocaesium activity at Ogoya Underground Facility to obtain reliable activity. 137Cs was detected at all stations and 134Cs was detected at most of the stations in the North Pacific Ocean. The 137Cs activity ranged from around 1 to 1,000 Bq m?3 with activity ratios of 134Cs/137Cs close to 1 which is a signature of radiocaesium originated from the FNPP1 accident. At east of the International Date Line north of 40°N in the Pacific Ocean in April 2011, the 134Cs activity ranged from 2 to 12 Bq m?3. 相似文献
20.
M. K. Fasasi P. Tchokossa J. O. Ojo F. A. Balogun 《Journal of Radioanalytical and Nuclear Chemistry》1999,240(3):949-952
The radioactivity of the Opa river — irrigated farmlands in the south western Nigeria was determined using an HpGe based,
low-level passive gamma-counting system. With the exception of two isotopes, the main radionuclides analysed in the sample
were the progenies of238U and232Th. The other two isotopes were the naturally occurring40K and the anthropogenic137Cs. The result obtained showed elevated levels of radioactivity from all detected radionuclides compared to the published
data for this area. Enhanced levels of naturally occurring radionuclides is attributed to the use of phosphatic fertilizers
for dry season vegetable cultivation along this river banks. The presence of the fission product137Cs could be traced to the fallouts occasioned by the various French nuclear tests in the Sahara desert, and probably, some
effect of the more recent nuclear reactor accident at Chernobyl in 1986. 相似文献