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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 investigate the operation status and service level of radiation occupational health inspection institutions in Zhejiang Province, China, and to provide a basis for administrative departments and quality management departments to develop policies. Methods The investigation data of radiation occupational health inspection institutions in Zhejiang Province were collected for descriptive analysis of the regional distribution, nature, and service qualification of the institutions. Results There were 27 radiation occupational health inspection institutions in Zhejiang Province. These institutions were located in 11 cities, of which 85.18% were public institutions and 14.72% were private institutions. For the physical examination workload of radiation workers in Zhejiang Province in 2021, general hospitals accounted for 75.90%, private institutions accounted for 4.51%, and occupational prevention and treatment hospitals accounted for 19.59%. In the radiation occupational health inspection institutions, the stand-alone and online software installation rates were 33.33% and 37.04%, respectively. A total of 26 986 individuals (82.97%) underwent chromosome aberration examination. The examination rates of thyroid color Doppler ultrasound examination and eye lens examination were 41.24% and 82.97%, respectively. Pre-job, on-job, and off-job physical examination accounted for 25.81%, 70.52%, and 3.67%, respectively. For radiation workers who underwent on-job physical examination, diagnostic radiology workers accounted for the highest proportion of 34.90%. The excellent, qualified, and unqualified rates of 27 radiation occupational health inspection institutions were 7.41%, 88.89%, and 3.70%, respectively. Conclusion The network of radiation occupational health inspection institutions in Zhejiang Province is well-established and located mainly in general hospitals, occupational prevention and control institutions, and private institutions. To enhance the quality and proficiency of occupational health examinations, it is imperative to prioritize self-improvement and management, reinforce law enforcement supervision, actively engage in blind sample assessments, and advance the application of information technology and standardized services.
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Objective:To investigate the levels of gross radioactivity in drinking water in Hangzhou city before and after Qiandao Lake as the water source to the main urban area of Hangzhou.Methods:Since 2012, water samples were collected from water source, factory water and peripheral water in rainy and dry seasons, respectively, to determine their gross α and β activity concentrations for comparison and analysis.Results:The gross radioactivity levels in drinking water in Hangzhou are lower than the limits specified in the national standard "Standards for drinking water quality" (GB 5749-2006), without statistically significant difference for these water sources between the rainy and dry season ( P>0.05). The gross α(0.008±0.000)and gross β(0.034±0.013)levels in Qiandao lake were both less than those in Qiantang river ( Z=-3.235, -4.058, P<0.05), with significant difference ( Z=-2.181, -4.577, P<0.05). There was no significant difference in gross α and gross β in factory water and peripheral water before and after the operation of Qiandao Lake water supply project ( P>0.05). Conclusions:The gross radioactivity in drinking water in downtown Hangzhou are low from 2012 to 2020. The gross radioactivity levels in Qiandao Lake are lower than in the lower reaches of Qiantang river and Dongtiao steam. No impact was generated on radioactivity levels in drinking water after Qiandao lake supplied water to Hangzhou.
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Objective:To investigate the data on death cause of residents around Sanmen nuclear power plant from 2015 to 2019.Methods:The data on death cause of residents in Sanmen county from 2015 to 2019 were collected, and the top 10 diseases in death causes ranking and radiation-related malignant tumors were analyzed.Results:The average mortality rate of residents in Sanmen county was 575.87 per 100 000 population from 2015 to 2019, lower than the national level and close to that in Zhejiang Province. The top 10 death causes remain unchanged, higher than 95.79% of total deaths. The mortality rate of malignant tumor increased from 159.23 per 100 000 population in 2015 to 191.51 per 100 000 population in 2019 (χ 2=15.889, P<0.05). There was no significant difference in the proportion of mortality from radiation-related tumor(leukemia and thyroid cancer) in Sanmen county in recent 5 years ( P>0.05). Conclusions:From 2015 to 2019, the death rates of residents in Sanmen county were relatively stable. The effects of the operation of the nuclear power plant on the health of the local residents need to be continuously monitored.
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Objective:To investigate and analyze the radioactivity levels of 90Sr and 137Cs in drinking water and 137Cs in food after the installation of the first AP1000 nuclear power unit in China. Methods:From 2012 to 2019, four drinking water monitoring points around AP1000 nuclear power unit located at Sanmen nuclear power plant site were collected during the wet season and dry season, 90Sr and 137Cs and radioactivity concentrations were determined in drinking water. Local rice, cabbage, crucian and mullet were collected to determine the radioactivity concentration of 137Cs. Results:From 2012 to 2019, the radioactivity concentrations of 90Sr and 137Cs in drinking water were 1.2-9.8 mBq/L and 0.2-8.1 mBq/L, respectively. The radioactivity concentration of 137Cs in food were 1.1×10 -2-2.8×10 -1 Bq/kg, lower than the limits specified in the Limited concentrations of radioactive materials in foods (GB 14882-94). Conclusions:After the installation of the first AP1000 nuclear power unit in China, the radioactivity levels of 90Sr and 137Cs in drinking water and 137Cs in foods are stable, without environmental impact identified.
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Objective:To investigate and analyze the radioactivity level of 90Sr in offshore seawater and seafood therein around Sanmen nuclear power plant (NPP) and to estimate the annual committed effective dose to local population from ingestion of 90Sr in seafood from 2015 to 2019. Methods:From 2015 to 2019, the offshore seawater and 3 kinds of marine products grown locally in Sanmen and consumed by local residents were collected for measurement of the level of 90Sr radioactivity. The committed effective doses to the local population were estimated based on monitoring result and consumption data on seafood in Zhejiang offshore. Results:The radioactivity concentrations of 90Sr ranged from 2.4 to 4.1 mBq/L in the seawater, close to the natural radioacrive background level and from 6.7×10 -2 to 1.3 Bq/kg in seafood, lower than the standard values specified in the "Limited concentrations of radioactive materials in foods" (GB 14882-94). Annual committed effective dose to the local population from 90Sr attributable to consumption of seafood in Sanmen County from 2015 to 2019 were 2.2×10 -4-4.2×10 -4mSv, respectively, far lower than the worldwide committed effective dose result ing from internal exposure. Conclusions:From 2015 to 2019, the radioactivity concentration of 90Sr in seawater and seafood are stable, with neglectable dose burden to the local population.
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Objective:To investigate the levels of gross radioactivity in drinking water and of 90Sr in food around Sanmen nuclear power plant (NPP) before and after operation. Methods:From 2012 to 2019, 7 drinking water monitoring sites were selected around the Sanmen NPP to collect source water, factory water and peripheral water, respectively, in order to measure and analyze the total radioactivity level in drinking water. Based on the dietary habits of local residents, 4 kinds of food such as grains, vegetables, freshwater fish and marine fish grown locally were sampled to measure and analyze the activity concentration of 90Sr. Results:Before the operation of Sanmen NPP, the total α radioactivity and total β radioactivity in drinking water around the NPP were 0.001-0.063 Bq/L and 0.019-0.210 Bq/L, respectively. After operation, the total α radioactivity and total β radioactivity were 0.001-0.084 Bq/L and 0.025-0.079 Bq/L, respectively. Both were lower than the national standard value given in the GB 5749-2006 " Sanitary standards for drinking water" . There was no significant change in the radioactivity level of source water, factory water and peripheral water during the wet and dry periods. The activity concentration of 90Sr in these four types of food ranged from 0.037 to 1.216 Bq/kg before operation and from 0.049 to 0.692 Bq/kg after operation, all lower than the standard value of " Standard for the concentration in radioactive substances in food" (GB 14882-94). Conclusions:Before and after the operation of Sanmen NPP, the total α and total β radioactivity in drinking water and 90Sr activity concentration in food are stable, below the national standard limit.
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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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Objective To establish a rapid,high-efficiency and clean way to monitor and pretreat the radioactivity in foods.Methods Food samples,20 kg each of cabbage,crucian,shrimp,pork and 20 L of milk,were collected around Qinshan nuclear power plant,totaling 10 samples for each food.Each type of foods was arranged in two groups each with 10 samples.Samples were pretreated using traditional ashing method (TAM) and microwave ashing method (WAM) separately.HDEHP were used for 90Sr separation and measurement.Calculations were made for the time spent on food pretreatment.The ash-fresh ratio and the recovery rate of 90Sr by the two different method were calculated,with the quality of ash being evaluated.Results The mean time spent on pretreatment was cabbage 20 h,crucian 54 h,shrimp 46 h,pork 58 h and milk 74 h for TAM group,and cabbage 8.5 h,crucian 26 h,shrimp 23 h,pork 26 h and milk 30 h for WAM group,respectively.The time spent by WAM was half the time less than by TAM,especially for animal edible product.The ash-fresh ratios from WAM group were higher than from TAM group.The recovery rates of 90Sr from WAM group in the analytical process were all above 75％,higher than from TAM group.Ashes produced by WAM were hoary,uniform,carbon residue-free and fully ashed.Conclusions WAM pretreatment can pretreat food rapidly,efficiently,cleanly with less loss and better ashing effect.These can meet the requirement of rapid pretreatment of radioactivity in food.
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Objective@#To investigate the individual irridiateddose levelandhealth statusofoccupational externalexposureamong radiationworkers inThreeA hospitals ofZhejiangprovince,andprovideevidence for occupationalhealthmanagement.@*Methods@#367 different typesof radiationworkerswereexperienced thedose monitoring and health examination from January toDecember, 2015, according to the requirements of"SpecificationsofIndividualMonitoring forOccupationalExternalExposure"and"Specifications forOccupational healthsurveillance forradiationworkers".The resultsofdosemonitoring,chromosomeaberration rate, lensopacity rate,hemogramand thyroid functionwerestatisticallyanalyzed.@*Results@#Theannualeffectivedoseamong radiation workers fromZhejiangprovince in2015was0.13mSv,98.91%of them less than1mSv,whichunder the limit standardofstate(20mSv/a).Thechromosomeaberration(dicentric)detection rateswere7.41%and4.35%, from nuclearmedicinegroupand interventionalgroup respectively,whichhigher thandiagnostic radiologygroup, the differencewasstatisticallysignificant(χ2=13.686,8.092,P<0.01).Besides,1caseofsuspiciouschronic radiation dermatitiswas found in the interventiongroup.Radiation lengthhadsignificanteffecton lensopacity rate(P<0.01), lensopacity increasedwith the increasing lengthof the linear trend (χ2trend=16.363,P<0.01),and the incidence ofabnormalthyroid function theabnormalrateof lymphocyte ratiohad significantdifferenceamong theagegroups (P<0.05).@*Conclusion@#Although, theoccupationalexternalexposureamong radiationworkersinThreeAhospitals ofZhejiangprovince issafe, long-term lowdosesofionizing radiation stillhascertainhealtheffectson the fieldof nuclearmedicineand interventionalradiologystaff,suchaseye lens,cytogenetics,nailsandskin.
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Objective To explore the current status of radiation protection in interventional procedure and to analyze the existent problems.Methods Using the random sampling,70 interventional radiology workplaces were selected from Hangzhou,Ningbo,Wenzhou,Shaoxing and Jinhua.Information on personal radiation protective products and equipment was collected by filling out the form by hospital and the radiation dose was monitored at various body parts of the workers and at the outside of the operating room.Results All hospitals have been equipped with personal radiation protective products and equipment,22 of which were not with these products and equipment as required.Chest,abdomen and lower limb of interventional radiology workers are easy to receive higher radiation dose than in head (F =4.85,4.92,P ＜ 0.05).The acceptance rates among different body parts of the workers were difference significantly (x2 =35.14,14.92,P ＜ 0.05).Using protective curtain can reduce the radiation dose significantly (t =11.61-68.28,P ＜ 0.05).Meanwhile,it also can improve the acceptance rates significantly (x2 =6.09-28.45,P ＜ 0.05).Conclusions It is necessary to strengthen the use of radiation protection equipment among interventional radiology workers to reduce the levels of the individual doses to them.Hospitals must enhance the routine monitoring for improved radiaton protection.
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Objective To study the effect of the long-term operation of a nuclear power plant (NPP) on population health,and to collect the health related data of the population around (NPP).Methods Four research areas,named 0-10 km area,10-20 km area,20-30 km area and control area,were set up interms of the distance from the nuclear power plant.Human blood samples were collected to detect chromosome aberration and lymphocytes subsets.Results The rates of cells with chromosome aberration at 0-10 km area,10-20 km area,20-30 km area and control area were 0.157％,0.167％,0.070％ and 0.111％,respectively.The differences of rates in the four areas were not statistically significant.The percentages of T lymphocytes,helper T lymphocytes,suppressor T lymphocytes,B lymphocytes and natural killer lymphocytes were all normal.The difference of percentages among 0-10 km area,10-20 km area,20-30 km area were not statistically significant.Conclusions In the operational condition,less significant impact is caused to the population around nuclear power plant.
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Objective To investigate the concentrations of indoor radon (222Rn) and its daughter products as well as indoor thoron (220Rn) in selected houses in Yuhang district and Sanmen county,Zhejiang province,and estimate their annual effective doses to the population.Methods Solid state nuclear track detectors were used in selected dwellings in Yuhang district and Sanmen county,and the detectors were placed in bedrooms or living rooms.Without changing the ventilation habits of residents,These detectors were continuously placed from March to September in 2009.Results Indoor 222 Rn and 220Rn concentrations in low-rise buildings were the highest among all types of houses.The indoor concentration of 222 Rn had no relation with the building age (F = 0.53,P ＞ 0.05),but that of 220 Rn was dependent on the building age (F = 3.56,P ＜ 0.05).Moreover,the investigation demonstrated indoor 220 Rn concentrations in houses with no decoration were higher than in the houses decorated (t = 2.33,P ＜0.05).The average indoor concentrations of 222Rn and 220Rn in Yuhang district were 32.5 Bq/m3 and 314.3 Bq/m3,respectively,and the annual effective doses were 0.88 mSy and 0.42 mSv respectively.The average indoor concentrations of 222Rn and 220Rn in Sanmen county were 26.8 Bq/m3 and 399.5 Bq/m3,and the annual effective doses were 0.72 mSy and 0.53 mSv respectively.Conclusion The concentrations of indoor 222 Rn in some areas of Zhejiang province are at natural background level,and the concentrations of indoor 220Rn in rural areas are relatively higher.The total annual effective dose from 220Rn and its progeny was larger than that from 222Rn and its progeny by 50 percents.