Internal occupational dosimetry for the occupational worker exposed to [18F] FDG from the Cyclotron-PET/CT Laboratory of the Universidad de Costa Rica / Dosimetría ocupacional interna para el personal trabajador expuesto a [18F] FDG del ciclotrón-PET/CT en el Laboratorio de la Universidad de Costa Rica

ABSTRACT: The aim of this work is to provide a methodology for evaluating the committed effective dose E(50) due to the incorporation of [18F] FDG in the occupationally exposed worker (OEW) of the Cyclotron-PET/CT Laboratory of the Centro de Investigación en Ciencias Atómicas, Nucleares y Moleculares (CICANUM) at Universidad de Costa Rica using in vivo measurements. The measurement system was calibrated to perform in vivo measurements and defined as the corresponding bioassay function for the radiopharmaceutical used. The conversion factor was assessed with a known activity of 18F in the geometry and measurement time established. Among the most relevant results, the measurement parameters and the calibration procedure were defined. A value of 1.73 x 103 Bq/cps for in vivo brain measurements was obtained as a conversion factor. This study provides a methodology, to evaluate the committed effective dose due to the incorporation of 18F-FDG in a radionuclide production and diagnostic center

Internal exposure levels of thyroid 131I in nuclear medical staff / 环境与职业医学

Background Based on numerous epidemiological studies, radionuclide 131I can result in thyroid disease. Objective To study the contamination level of thyroid 131I in 131I treatment associated radiation workers in nuclear medicine departments in Shanghai. Methods Based on a general survey on basic situation of nuclear medicine in Shanghai, the level of internal exposure of radiation workers involved in 131I treatment was assessed with questionnaires and on-site monitoring. A portable γ spectrometer was used for on-site detection, the intake and annual effective dose were estimated according to the measurement results. Physical examination reports were collected for radionuclide positive workers, and chromosome testing was performed. Results There were 579 nuclear medicine workers and 175 were engaged in 131I treatment in Shanghai. 131I was detected in thyroid of 18 workers, with a detection rate of 10.3%. Among them, the detection rates of thyroid 131I in nurses and cleaners were 23% and 25% respectively. The mean measured activity of thyroid 131I was 306.1 Bq and the maximum measured activity was 3716.9 Bq (nurse). The maximum intake was estimated at 37544 Bq and the median was 786.4 Bq. The average annual committed effective dose was 1.22 mSv and the maximum value was 14.87mSv. The chromosomal aberration rates of all detected workers were negative, and all blood indicators were normal except one with low hemoglobin. Conclusion The annual dose of nuclear medical staff engaged in 131I treatment does not exceed the national standard limit, but the internal exposure of nurses and cleaners should not be ignored. On the basis of strengthening protection and decontamination, routine internal exposure monitoring should be carried out.

Investigation on 90Sr level in offshore seawater and seafood therein around Sanmen nuclear power plant site and assessment of committed effective dose from 2015 to 2019 / 中华放射医学与防护杂志

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.

Assessment of committed effective dose from ingestion of 137 Cs in seafood from coastal areas of Zhejiang province / 中华放射医学与防护杂志

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.

Assessment of committed effective dose from ingestion of 137Cs in seafood from coastal areas of Zhejiang province / 中华放射医学与防护杂志

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.

Variation in activity concentration of 210Pb in atmospheric aerosol and its radiation dose assessment in Qingdao / 中华放射医学与防护杂志

Objective To investigate the variation patterm in activity concentration of 210Pb in atmospheric aerosol in Qindao and evaluate its internal radiation effect to human body.Methods 210Pb activity concentration of aerosol samples was measured by high purity germanium(HPGe) γ spectrometer for purpose of ascertaining its variation in aerosol in Qingdao from April 2015 to March 2016.Results 210Pb activity concentration in aerosol varied from 0.06 to 1.61 mBq/m3 and the mean of (0.70 ± 0.50) mBq/m3,slightly higher than the UNSECAR 1988 report recommended value of O.50 mBq/m3.In this study,210Pb activity concentration in aerosol was high from December 2015 to February 2016 and low from August to November.Radiation dose assessment revealed that the annual committed effective dose to adults delivered by 210Pb was 6.35 × 10-6 Sv.The monthly variation in activity concentration variation of 210Pb in atmospheric aerosol in Qingdao was similar as in Xiamen.Conclusions Activity concentration of 210Pb in atmospheric aerosols in Qingdao varied largely dependent on atmospheric environmental pollution.210Pb contributed less to the adult annual committed effective dose.However,more attention should be drawn to the long-term radiation effects to aduhs due to the 210Pb potentially deposited in lungs.

Estimation of internal dose with aerosol clust inhaled by non-uranium miners / 中华放射医学与防护杂志

Objective To establish a method for estimating internal dose from aerosol inhalation in non-uranium miners.Methods Aerosol samples in a tunnel in Dongchuan Copper Mine in Yunnan Province were collected by portable high flux air sampler.Radionuclides collected at the sampler filters were analyzed by the gamma spectrometry.Annual committed effective dose due to inhalation of the aerosol dust was estimated using the formula provided by ASTM.Results Radionuclides collected in two aerosol samples were anlayzed,the annual committed effective doses due to inhalation of 1 μm and 5 μm aerosol were estimated.Conclusions The method of using high flux air sampling and gamma spectrometry is explored to estimate the dose from aerosol inhalation.