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Objective To understand the radioactivity level of food surrounding a uranium mine in Xinjiang, to supplement the baseline database of food radionuclides in Xinjiang, to analyze the content of radionuclides and to estimate the internal exposure dose of residents caused by dietary intake. Methods The specific activity of 238U, 232Th, 226Ra, 40K and 137Cs of interest nuclides was measured, statistically analyzed by high purity germanium γ spectrometer, and the annual effective dose of these nuclides was estimated. Results No nuclide 238U was detected in food samples from 2018 to 2020. The average activity concentration and detection rate of other radionuclides were 232Th: 0.428 ± 0.038 Bq/kg (18.3%)、226Ra: 0.477 ± 0.063 Bq/kg (38%)、40K: 162 ± 7 Bq/kg (100%)、137Cs: 0.071 ± 0.011 Bq/kg (29.6%). The annual effective dose of residents due to food radionuclides was about 0.198 mSv. Conclusion The radioactivity level of food in the vicinity of a uranium mining mountain in Xinjiang is within the national standard limit, and the average annual effective dose caused by the diet of residents is consistent with the report of UNSCEAR in 2000. The content of artificial radionuclide 137Cs detected in food samples will not cause harm to the health of residents.
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OBJECTIVE: To investigate the individual external dose level of medical radiation staffs in Guangzhou City.METHODS: The medical radiation staffs of Guangzhou City who conducted individual dose monitoring at Guangdong Province Hospital Center for Occupational Diseases Prevention and Treatment from 2008 to 2014 were selected as study subjects by convenient sampling method.Their individual dosage monitoring data were analyzed.RESULTS: A total of 17 754 person-times were monitored in 7 years.The annual collective effective dose was 10 621.1 person·mSv and the median per capita annual effective dose was 0.21 mSv/a.The per capita annual effective dose in 2008-2012 showed an increasing trend each year( P < 0.05),peaked in 2012,and then decreased in 2013 and 2014( P < 0.05).The per capita annual effective dose of radiology staffs in level Ⅱ medical institutions was higher than that of level Ⅲ medical institutions,level Ⅰ medical institutions and those below level Ⅰ( P < 0.01).The per capita annual effective dose of radiation staffs in level Ⅲ medical institutions was higher than level Ⅰ medical institutions and those below level Ⅰ( P <0.01).The effective monitoring rates of radiation staffs monitored for 4 cycles every year increased with time from 2008 to 2014( P < 0.01).The effective monitoring rate increased with the hospital level( P < 0.01).The per capita annual effective dose of the staffs in radiological diagnosis department was lower than that of clinical nuclear medicine,radiotherapy and interventional radiology( P < 0.01).CONCLUSION: The radiation dose of medical radiation staffs in Guangzhou City was within the national standard limit.Protection should be focused on the the staffs in secondary hospitals,clinical nuclear medicine,radiotherapy and interventional radiology.
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Context: It has been proved from many epidemiological studies that the inhalation of the radioactive, inert gas radon (222Rn) is the main cause of lungs cancer after smoking. Objective: The survey was conducted to estimate the indoor radon concentration, the annual effective dose rate and the annual dose equivalent rate to the lung. Material and Methods: Altogether 50 dwellings were chosen randomly at 5 different districts of Nepal. The dosimetric measurements were carried out over a period of 3 months using time-integrated passive radon detectors, CR-39 based on type II Solid State Nuclear Track Detector (SSNTD) technique. The type of houses was concrete with plastered walls and mud house. Results: The minimum concentration of radon in the study areas was found to be <20Bq.m-3 and the maximum concentration was 110±20Bq.m-3. Also the corresponding values of annual effective dose and annual equivalent dose to the lung respectively varied from <0.60 to 3.30mSv.y-1 and 0.16×10-7 to 0.88×10-7 Sv.y-1. The uncertainty was measured at 95% confidence level. Conclusion: The indoor radon concentration varies considerably with the ventilation condition, lifestyle of the people, construction of the dwellings and climate of the areas. The measurements show that the radon concentrations were found to be well below the reference levels of ICRP.
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<p><b>OBJECTIVE</b>To investigate the annual effective doses from indoor radon received by academic staff in the Faculty building.</p><p><b>METHODS</b>Measurements of indoor radon concentrations were performed in the Arts and Sciences Faculty of Dokuz Eylül University for two surveys of about 1 month duration respectively using the SSNTD (Solid State Nuclear Track Detectors) method with LR115 detectors. Time integrated measurements comprised different locations inside the faculty building: classrooms, toilets, canteen and offices. Homes of academic staff were also tested for radon.</p><p><b>RESULTS</b>The arithmetic mean radon concentration is 161 Bq m-3 with a range between 40 and 335 Bq m-3 in the Faculty. Six offices and three classrooms have a radon concentration above 200 Bq m-3. The results show that the radon concentration in classrooms is generally higher than in offices. Based on the measured indoor radon data, the annual effective doses received by staff in the Faculty were estimated to range from 0.79 to 4.27 mSv, according to UNSCEAR methodology. The annual effective doses received by staff ranged from 0.78 to 4.20 mSv in homes. On average, the Faculty contributed 56% to the annual effective dose.</p><p><b>CONCLUSION</b>Reported values for radon concentrations and corresponding doses are within the ICRP recommended limits for workplaces.</p>
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Humans , Air Pollution, Indoor , Environmental Monitoring , Faculty , Housing , Radiation Dosage , Radon , Risk Assessment , Turkey , UniversitiesABSTRACT
Objective To estimate the dose to non-uranium miners from external exposure.Methods Ore samples of non-uranium mines were collected in site and analyzed with gamma spcetrometry,then annual dose to the miners was estimated based on the measured radioactivities of radionuclides.Results Thirty-two ore samples in thirteen mines in seven provinces were collected and analyzed.Among them,radioactivity concentrations in two samples were higher than others,and the annual doses from external exposure to the radionuclides in the two ore samples were estimated to be higher than 1 mSv/a.Conclusions Gamma spectrometry is fit for determining the radionuclides concentrations and its results can be used for estimating dose from external exposure in non-uranium mines.
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Objective To measure 222Rn and 220Rn concentrations in the underground non-uranium mines in Shandong Province,and to estimate the annual effective dose to the miners.Methods Concentrations of 222Rn and 220Rn in selected gold,iron,coal and clay mines were determined by passive time-integrating detectors with CR-39.Activity concentrations of 226Ra,232Th and 40K were determined using gamma spectrometry equipped with HPGe detector.Results The average concentrations of 220Rn in the gold,iron,coal and clay mines were estimated to be 1200,280,120 and 40 Bq/m3,respectively.The activity concentrations of 226Ra,232Th,40K in the ores for gold,iron,coal and clay mines ranged the same as the soil in China.The annual effective dose due to radon exposure in gold and iron mine was 7.70 mSv and 1.74 mSv,respectively.The annual doses received by miners in the coal and clay mines were lower than 1 mSv.Conclusions Underground miners in some gold and iron mines should be treated as workers occupationally exposed to ionizing radiation.The measurement such as increasing ventilation should be implemented to reduce underground radon concentration in these mines.