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Objective:To investigate the activity concentrations of 90Sr and 137Cs in water in Hangzhou urban area. Methods:From 2012 to 2020, Qiantang River water as an important drinking water source, tap water as direct drinking water for residents, and West Lake water in tourists crowded area were selected forwater quality monitoring with respect to conctnts of 90Sr and 137Cs. The activity concentrations of 90Sr and 137Cs in water samples, as collected in wet and dry seasons resepectively, were determined by radiochemical analysis, with the 137Cs to 90Sr activity ratios obtained. Results:From 2012 to 2020, the activity concentrations of 90Sr and 137Cs in tap water were (2.0±1.1) - (7.4±0.4) mBq/L and (0.45±0.06) - (7.1±0.6) mBq/L, respectively. The 137Cs to 90Sr activity ratios ranged from 0.07 to 2.40. The activity concentrations of 90Sr and 137Cs in Qiantang River were (3.7±1.1) - (17.0±4.4) mBq/L and (0.28±0.01) - (15.0±4.5) mBq/L, respectively. The 137Cs to 90Sr activity ratios ranged from 0.03 to 0.90. The activity concentrations of 90Sr and 137Cs in West Lake water were (2.2±0.5) - (11.0±2.0) mBq/L and (0.32±0.04) - (7.9±1.9) mBq/L, respectively. The 137Cs to 90Sr activity ratios ranged from 0.05 to 1.20. Conclusions:The activity concentrations of 90Sr and 137Cs in water in Hangzhou urban area were at the background levels, lower than the concentration limits, 10 Bq/L both for 90Sr and 137Cs recommended by WHO in the 4 th edition of Guidelines for Drinking Water Quality.
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Objective To improve the analysis of 134Cs, 137Cs, and 60Co in aerosol samples by the national key radiation environment laboratories. Methods Intercomparison of analysis results of 134Cs, 137Cs, and 60Co in standard aerosol samples was performed among the national key radiation environment laboratories according to Gamma spectrometry method of analyzing radionuclides in biological samples (GB/T 16145-1995 ), and the intercomparison results were evaluated by the standard deviation. Results Six laboratories were involved in the intercomparison. For 134Cs, 50% of the laboratories showed a relative deviation less than 10%, and 50% showed a relative deviation of 10%-20%. For 137Cs, 33.3% of the laboratories showed a relative deviation less than 10%, and 76.7% showed a relative deviation of 10%-20%. For 60Cs, all laboratories showed a relative deviation less than 10%. The overall intercomparison results were acceptable. Conclusion The laboratories in this intercomparison show generally good results.
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Objective@#To investigate the contents of radionuclide 137Cs in seafood from coastal areas of Zhejiang province, and to estimate the annual committed effective dose to population in different regions from ingestion of 137Cs in seafood.@*Methods@#Three representative monitoring areas were set on the coastaline of Zhejiang province, and the locally popular seafoods were selected as monitoring objectives. The contents of radionuclide 137Cs were detected using HPGe γ spectrometry. The committed effective doses were estimated based on monitoring results and consumption data on seafoods in Zhejiang.@*Results@#The detection ratio of 137Cs in seafood produced on coastal areas of Zhejiang province was estimated to be 35.3% (36/102). Specific activity detected ranged from 0.004 to 0.140 Bq/(kg, Wet). Committed effective doses from ingestion of 137Cs in one year to the population in island region, coastal region and inland region were 3.03×10-5, 1.63×10-5, 3.38×10-6 mSv, respectively, far lower than the world committed effective dose resulting from internal exposure.@*Conclusions@#At present, the content level of 137Cs in seafood produced on the coastal areas of Zhejiang province is much lower than the national standard limit, and the dose burden to the population is very minor with no health impact to the population.
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Objective To investigate the contents of radionuclide 137 Cs in seafood from coastal areas of Zhejiang province, and to estimate the annual committed effective dose to population in different regions from ingestion of 137 Cs in seafood. Methods Three representative monitoring areas were set on the coastaline of Zhejiang province, and the locally popular seafoods were selected as monitoring objectives. The contents of radionuclide 137 Cs were detected using HPGeγspectrometry. The committed effective doses were estimated based on monitoring results and consumption data on seafoods in Zhejiang. Results The detection ratio of 137 Cs in seafood produced on coastal areas of Zhejiang province was estimated to be 35.3％ ( 36/102 ) . Specific activity detected ranged from 0. 004 to 0. 140 Bq/( kg, Wet ) . Committed effective doses from ingestion of 137 Cs in one year to the population in island region, coastal region and inland region were 3. 03 × 10-5 , 1. 63 × 10-5 , 3. 38 × 10-6 mSv, respectively, far lower than the world committed effective dose resulting from internal exposure. Conclusions At present, the content level of 137 Cs in seafood produced on the coastal areas of Zhejiang province is much lower than the national standard limit, and the dose burden to the population is very minor with no health impact to the population.
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BACKGROUND: In 2011, two roads in a residential area in Seoul were found to be contaminated with the radionuclide cesium-137 (137Cs). In response to public concerns, an epidemiological study was conducted. METHODS: The standardized cancer incidence ratios in the affected and neighboring regions were calculated based on the central cancer registry. Households in the region were sampled using the random stratified sampling technique, and questionnaires were administered to family members, via home visit and via students in elementary to high schools. Information on duration of residency and frequency of use of the roads was applied to calculate cumulative radiation exposure dose from the roads, alongside with the reported 137Cs contamination amounts. Information on past medical history, perceived risk, anxiety and psychological stress was also obtained. Of the 31,053 residents, 8,875 were analyzed. To examine possible associations between radiation exposure and health problems, logistic regression adjusted for covariates were performed with consideration of the sampling design, population weight and stratification. RESULTS: No significant association was found between self-informed diseases, including cancers, and estimated radiation exposure dose. According to an increase of radiation level, a significant increase in anxiety in all and a decline in the psychosocial wellbeing of the adults was noted. The risk perception level was higher in the elderly, females, the less educated, and the highest exposed individuals. CONCLUSION: This study provides a basis for risk communication with residents and community environmental health policy.
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Adult , Aged , Female , Humans , Anxiety , Environmental Health , Epidemiologic Studies , Family Characteristics , House Calls , Incidence , Internship and Residency , Logistic Models , Radiation Exposure , Seoul , Stress, PsychologicalABSTRACT
Objective To observe the different radiosensitivity induced by different doses of 137Csγ-ray irradiation between hematopoietic stem and progenitor cells. Methods Seventy-two C57BL/6 mice were randomly divided into control group and irradiated groups (2, 4 and 6 Csγ-ray irradiation, n=18 for each group). Mice of control group received sham irradiation, and the rest accepted 2, 4 and 6 Gy137Csγtotal body irradiation, respectively. After 14-day, 35-day and 56-day irradiation, the peripheral blood samples were collected by balls enucleation. The number of bone marrow nuclear cells, hematopoietic stem and progenitor cells were counted. Results The peripheral blood of irradiated mice showed significant changes in the number of white blood cells (WBC), red blood cells (RBC), platelets (PLT) and hemoglobin (HGB) in a dose-response relationship. Compared with the control group, the numbers of BMNCs and hematopoietic progenitor cells (HPCs) were significantly lower in irradiated group. At 35 d and 56 d after 6 Gy irradiation the numbers of BMNCs and HPCs were significantly lower than those of control group (P<0.05). There were no significant differences in numbers of BMNCs and HPCs between irradiated groups (2 and 4 Gy) and control group. The number of bone marrow hematopoietic stem cells (HSCs) was significantly lower in irradiated group than that in control group after 14-d and 56-d irradiation (P<0.05). Conclusion 137Csγ-ray irradiation has some damage in mouse hematopoietic system. The damage caused by radiation is persistent to hematopoietic stem cells.
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Objective To determine the activity concentration of radionuclides for 137Cs and 40K in edible wild mushrooms,and to evaluate the extent of radioactive contamination and ingestion doses to adults from consumption of these wild mushrooms.Methods A total of 33 samples for 18 edible wild mushroom species were collected from natural forest Mangshi,Yunnan province.The activity concentrations of 137Cs and 40K were analyzed by using high-purity germanium (HPGe) gamma spectrometry.Results Except.for one sample that was below the MDA,137Cs artificial radionuclides were detected in other 32 samples,with activity concentration of 137Cs in the range of 0.45-339.58 Bq/kg (dry weight) and an average of 25.47 Bq/kg (dry weight).In regards to 40K in edible mushrooms,all species presented the activity concentrations for this radionuclide and the levels varied from 453.4 to 1 882.6 Bq/kg (dry weight),with an average of 815.1 Bq/kg (dry weight).After species of mushroom with only one sample were eliminated,there was significant difference for 137Cs(F =21.13,P ＜ 0.05) among 6 species of mushroom named Gomphus floccosus (Schw.) Sing.,Boletus edulis bull,Boletus edulis bull,Tylopllus bolloul (Peck) Sing.,Lentinus edodes (Berk.) Sing.and Boletus brunneissimus W.F.Chin,but without significant difference for 40K.Conclusions These 6 different mushroom species have different capacity to retain radionuclides of 137Cs in soil.These wild mushrooms,such as Gomphus floccosus (Schw.) Sing.and Lentinus edodes (Berk.) Sing.have large affinity ability for radionuclides137Cs.The effective dose to adults attributable to consuming these kinds of mushrooms is small and below the level that could cause harm.
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Objective To determine the artificial radionuclides levels in environmental samples collected in some areas of China following the Japanese Fukushima nuclear accident,and to evaluate the extent of radioactive contamination.Methods A total of 118 samples including aerosol,water,soil and biological samples were collected and the activity concentrations of 131I, 137Cs and other artificial radionuclides were analyzed by using high-purity germanium (HPGe) γ spectrometry.Results Artificial radionuclides 131I,134Cs,137Cs and 136Cs were detected in the aerosol samples on 2 April,2011 and the activity concentrations were 1720,247,289,and 23 μBq/m3,respectively.Trace amount of 131I was detected in one sample of rain water and two samples of surface soil with concentrations of 2.08 Bq/L,1.82 and 0.59 Bq/kg,respectively.131I was also detected in 18 vegetable samples which were collected from 2 April to 13 April with the range of 0.55 -2.68 Bq/kg.Neither abnormal concentrations of 131I nor 137Cs was detected in milk,drinking water,sea water and marine products samples.Conclusions During the Fukushima nuclear accident,although minute quantities of radionuclides were detected in some samples collected in China,the effective dose for adults attributed to the nuclear accident is extremely small and significantly below the level that could cause harm to the public.
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OBJECTIVE To study the sterilization by gamma radiation on the cytokine levels in manually manipulated platelet concentrates, and its practicability. METHODS Manually manipulated platelet concentrates were irradiated by gamma ray at 25 Gy. Detected the quantity of cytokine levels after irradiation on dd 0, 1, 3, and 5. Platelet counts and pH value were detected on the d0 and d5. RESULTS The contents of cytokines increased with storage time both in irradiation and control groups. But the contents of cytokines in the control group increased more significantly than in the irradiation one (P
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PURPOSE: The objective of this study was to assess attenuation correction algorithms with the 137Cs point source for the brain positron emission tomography (PET) imaging process. MATERIALS AND METHODS: Four different types of phantoms were used in this study for testing various types of the attenuation correction techniques. Transmission data of a 137Cs point source were acquired after infusing the emission source into phantoms and then the emission data were subsequently acquired in 3D acquisition mode. Scatter corrections were performed with a background tail-fitting algorithm. Emission data were then reconstructed using iterative reconstruction method with a measured (MAC), elliptical (ELAC), segmented (SAC) and remapping (RAC) attenuation correction, respectively. Reconstructed images were then both qualitatively and quantitatively assessed. In addition, reconstructed images of a normal subject were assessed by nuclear medicine physicians. Subtracted images were also compared. RESULTS: ELAC, SAC, and RAC provided a uniform phantom image with less noise for a cylindrical phantom. In contrast, a decrease in intensity at the central portion of the attenuation map was noticed at the result of the MAC. Reconstructed images of Jaszack and Hoffan phantoms presented better quality with RAC and SAC. The attenuation of a skull on images of the normal subject was clearly noticed and the attenuation correction without considering the attenuation of the skull resulted in artificial defects on images of the brain. CONCLUSION: the complicated and improved attenuation correction methods were needed to obtain the better accuracy of the quantitative brain PET images.
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Brain , Noise , Nuclear Medicine , Positron-Emission Tomography , SkullABSTRACT
Objective To investigate the changes of buffy coat components after 25Gy 137Cs-irradiation.Methods Lymphocyte proliferation was detected by MTT,the fluorescent intensity of neutrophils was measured as phagocytotic rate by flow cytometry,O2-release was determined by cytochrome C reduction,and cytokine production pre-and post-irradiation was detected by ELISA.Results 25Gy is adequate to inactivate T cells.The percentages of phagocytosis of E.coli before and after irradiation were of no significant difference.The release of O2-increased significantly and monocytes maintained the ability to produce cytokines after irradiation.Conclusion Radiation does affect the components of buffy coat,and neutrophils isolated should be transfused as early as possible.
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This paper presents dose distributions in water around Fletcher-Suit colpostat containing 137Cs tube, and shielding effect of internal lead shield. Using ready packed film, author measured dose distribution in water around the colpostat containing cesium source. Nine sheets of films on one side of the colpostat are packed with acryl frames cut out so as to fill water, and irradiated in water by cesium source in the colpostat. Dose distributions on transverse plane and upper plane 0.5 cm from upper surface of the colpostat were measured. Shielding effect was greater in upper medial direction than in lower medial direction. And that was the greatest around 30degree from the axis of the colpostat on upper side and around 50degree on lower side. In the region 7 cm from the center of the colpostat, shielding efficiency was 0.23 to 0.35 on the lower 50degree and 0.26 to 0.42 on the upper 30degree, and decreased with increase of distance.