Annual dose rate for Qena governorate population due to consume the animal products

In this work, the natural radionuclide concentrations of the 226Ra, 228Ra, 232Th and 40K were estimated from samples of cattle and poultry fodder, South Valley University farms and Qena Governorate farm, Qena, Upper Egypt. The radionuclide concentrations and annual consumption rate of twenty-nine animal fodders were analyzed using low-level γ-spectrometer, including a mixture fodder, silage, hay, rice straw, and poultry fodder. The irradiation risk of human health was assessed due to indirect ingestion of the beef, milk, poultry and egg, the annual effective dose of the radionuclides for the local consumer was 2.7, 14, 0.1, and 0.14 μSv·y–1, respectively.

Level of natural radionuclides in foodstuffs and resultant annual ingestion radiation dose

The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using γ-ray spectroscopy. Another group of hay, water, and soil samples from the same location were also analyzed. Hay samples were found to contain the highest radioactivity concentration among all the samples that were investigated. This in- crement could be due to the high water content in the shoots which tends to accumulate soluble radionuclides. The average calculated concentrations of soil samples in the present study exhibits the lowest values with respect to those from different countries. In the case of water samples, the average activities of both 232Th and 40K were similar to those for soil while 226Ra was twice that of water sample. The annual ingestion dose from each radionuclide was cal- culated. The computed annual dose owing to daily intake of radium, thorium, and potassium via wheat flour, lentils, and bean in the present study (214.8 μSv) is ten times lower than the global average annual radiation dose (2400 μSv) from the natural radiation sources as proposed by UNSCEAR. The obtained results show that the dose values are quite low and carry insignificant radiation dose to the public.

Annual effective dose values from^137Cs activity concentrations in soils of Manisa,Turkey

In this study,the activity concentrations of the fallout radionuclide ^(137(Cs in 150 soil samples collected from 13 districts of Manisa Province were determined using a gamma ray spectrometer with a Na I(Tl) detector.The health risks to people resulting from external exposure were evaluated by estimating the outdoor absorbed gamma dose rate and annual effective dose rate(outdoor and indoor).The activity concentration of ^(137)Cs varied from 3.6 ± 2.0 to 124.1 ± 11.0 Bq kg^(-1),with an average value of43.3 Bq kg^(-1).The average values of the outdoor absorbed gamma dose rate and annual effective dose(outdoor plus indoor) were found to be 1.3 n Gy h^(-1),and 8.0 μSv y^(-1),(6.38 + 1.59 μSv y^(-1)),respectively.The results were compared with internationally recommended values.

Assessment of Equivalent Radium Activity and Annual Effective Dose Due to Building Materials in Côte D’Ivoire by Gamma Spectrometry: Cases of Cement

Radioactivity is a natural phenomenon present in the universe. So, because of human life solidarity with a habitat, we are permanently in contact, especially through building materials. The objective of this work is the determination of the used cement radioactivity level in the buildings in Cote d'Ivoire. Thus, samples of grey and white cement currently used on Ivorian territory were taken. In order to determine the radioactivity level of this cement, samples were analyzed by using gamma spectrometry chain which contains a NaI (Tl) scintillation detector designed by the German manufacturer LD-DIDACTIC, coupled to a multichannel analyzer (AMC) using a Cassy Lab software. Thus, the specific activity of the primordial radionuclides 226Ra, 232Th and 40K, was able to be determined. The average values obtained are 29.66 Bq/kg, 34.88 Bq/kg and 178.424 Bq/kg respectively for 226Ra, 232Th and 40K. All average values are below the limit values recommended by UNSCEAR. However, we evaluated the radiological parameters such as the equivalent radium activity and the annual effective dose in order to translate the specific activity in terms of harmfulness. Values obtained for these parameters are below those recommended by ICRP and UNSCEAR. These results show that the risk incurred by the use of these different brands of cement is low.

Radiological characterization of building materials used in Malaysia and assessment of external and internal doses

In this study, the activity concentrations of ^(226)Ra,^(232)Th,^(222)Rn, and ^(40)K, emanation fractions(P),equilibrium equivalent concentration(EEC), and mass exhalation rates(E_m) of radon released from building materials used in Malaysia were studied using gamma-ray spectrometer with HPGe detector. Radiological parameters[activity concentration index(ACI), indoor air-absorbed dose rate(D_(in)), annual effective dose(AED_(in)) from external and internal(E_(Rn)), soft tissues(H_(ST)) and lung(H_L), and effective dose equivalent(H_(eff))] were estimated to evaluate radiological hazards due to the use of these building materials: sand, cement, gravel, bricks, tiles, fly ash, white cement, and ceramic raw materials. The measured P, EEC,and E_m vary from 10 to 30%, 0.9 to 22 Bq m^(-3), and 33 to 674 mBq h^(-1) kg^(-1), respectively, while the calculated ACI and AED_(in) vary from 0.1 ± 0.01 to 2.1 ± 0.1 and 0.1 ± 0.01 to 2.4 ± 0.6 mSv y^(-1), respectively. On the other hand, the internal annual effective dose ranges from 0.1 to 1.4 mSv y^(-1). The estimated radiological risk parameters were below the recommended maximum values, and radiological hazards associated with building materials under investigation are therefore negligible.

Indoor^(222)Rn Levels and Effective Dose Estimation of Academic Staff in izmir-Turkey

Objective To investigate the annual effective doses from indoor radon received by academic staff in the Faculty building. Methods Measurements of indoor radon concentrations were performed in the Arts and Sciences Faculty of Dokuz Eylul 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. Results The aritthmetic 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. Conclusion Reported values for radon concentrations and corresponding doses are within the ICRP recommended limits for workplaces.

Total Indicative Dose Determination in Water from the North Riviera Well Field of SODECI in Abidjan, Cote d’Ivoire

The Uranium-238 (238U), Thorium-232 (232Th) families and Potassium-40 (40K) are of terrestrial origin and contribute generally to an individual’s external exposure through our presence in this environment. They also contribute to the internal exposure through the ingestion of products and beverages such as water that are close to the earth. The aim of this work is to determine the committed effective dose or Total Indicative Dose (TID) due to gamma radioactivity of the borehole water from the Nord Riviera (NR) well field operated by the Côte d’Ivoire Water Distribution Company (SODECI) for the supply of drinking water to part of the population of Abidjan. In addition, the populations, with their habits, could use these borehole waters directly as drinking water. To this end, water samples from the seven (07) functional boreholes were collected and analyzed on a gamma spectrometry chain, equipped with an HPGe detector in the laboratory of the Radiation Protection Institute (RPI) of the GHANA Atomic Energy Commission (GAEC). The results of the specific activities of 238U, 232Th and 40K obtained were transcribed into TID. As the natural radioactivity of the borehole water is high [1], the TIDs calculated from the activity results of the natural radionuclides238U, 232Th, and 40K vary for the seven boreholes from 0.150 to 0.166 mSv/yr with an average of 0.161 ± 0.034 mSv/yr. The TID of the control tower, where the borehole water is mixed and treated for household use, is equal to 0.136 ± 0.03 mSv/yr. The TIDs obtained are therefore all slightly greater than the WHO reference dose value of 0.1 mSv/yr. But all remain below the UNSCEAR reference dose of 0.29 mSv/yr.

Assessment of Radiation Dose for Non-Radiation Workers in the Medical Field Practices

Radiation protection programs aims to reduce the radiation dose to the lowest possible level under the Dose Limit (DL) limit by the national or international laws, while the dose monitoring programs working as scale used to evaluating the efficiency of these programs and tools. In this study, the average of the annual Eff dose for the intensive care units at Hamad General Hospital (HGH) is less than the 50% of DL. It was aiming also to evaluate the efficiency of the radiation safety requirements (especially the shielding Adequacy) for the non radiation workers at oncology centers, hence several monitors were installed in chosen locations outside the radiation treatment machine from 2007 to 2011.

Determination Uranium Concentrations and Effective Dose of Drinking Water for Nineveh Governorate—Iraq, Using Kinetic Phosphorescence Analyzer (KPA)

In this work, the concentrations of natural Uranium and the annual effective dose (ET in Sv·y-1) in drinking water for Nineveh Governorate in northern Iraq were determined using a pulsed-laser Kinetic Phosphorescence Analyzer (KPA). Furthermore, the relationship between pH for water samples and the concentration of Uranium was studied. The drinking water samples are taken approximately from all regions of Nineveh as;15 samples of tap water are taken from refinery stations, 13 samples of water samples are taken from wells that are used for drinking, and 18 samples of drinking water are withdrawn from wells in Adayyah region (this region is located near nuclear wastes site). Thus, the total studied samples are 46. The results of Uranium concentration for all samples ranged from 2.61 ± 0.08 to 9.14 ± 0.012 μg·L-1 with an overall average value about 5.87 ± 0.046 μg·L-1, and the total annual effective dose ranged from 2.3 to 8.04 μSv·y-1. The results also showed that the pH number increases with increasing Uranium concentration and have, in general, high values in well water.

Experimental and Simulated Effective Dose for Some Building Materials in France

The specific radioactivity of several building materials used in France, which is considered a direct exposure to radiation, has been assessed by γ-ray spectrometry. Corrected for coincidence summing and self-absorption effects, the values for 226Ra, 232Th and 40K were in the ranges 4 - 56, 3 - 72 and 9 - 1136 Bq·kg-1, respectively. The samples were found to have radium-equivalent activities between 5 and 245 Bq·kg-1. Values of 0.02 - 0.67 for the external and 0.03 - 0.82 for the internal hazard indexes were estimated. The calculated absorbed dose in air agrees closely with MCNPX simulations. The conversion of absorbed dose to annual effective dose gave values between 0.03 - 1.09 mSv·y-1. All these values are below action limits recommended by the International Commission on Radiological Protection. The materials examined would not contribute a significant radiation exposure for an occupant and thus are acceptable for construction.

成都市部分地下商场空气氡浓度测量研究

为了解成都市地下商场空气氡浓度水平,使用FD216型环境氡测量仪,对分散在成都市区的10家地下商城进行了空气氡浓度调查,总计测量点61个。测量后对工作人员和顾客的年有效剂量进行估计,并与以往测量结果进行对比分析。测量结果表明:地下商场室内空气氡浓度的平均值为30.9 Bq/m^(3),标准差为8.87 Bq/m^(3),分布在18.2~53.1 Bq/m^(3)范围内,远低于国家标准限值400 Bq/m^(3)。室外平均空气氡浓度为22.0 Bq/m^(3),低于室内平均空气氡浓度。商场工作人员年有效剂量平均值为0.527 mSv,低于国家标准限值1 mSv,顾客的年有效剂量更低。氡浓度测量值与以往测量值进行对比分析,成都市地下商场空气氡浓度均处于较低水平。

上海黄浦江特定段水域放射性核素测定与评价

为了解上海黄浦江特定段水域放射性核素U、Th、226Ra、210Po、210Pb含量等信息,根据黄浦江特定段水域及其支流分布情况,使用三点采样法布设15个采样点,共采集15个样品,优化了样品的处理及测定方法,评价了特定段水域放射性核素的测定结果。结果表明:汛期放射性核素的测量值高于枯水期,U、Th、226Ra、210Po、210Pb的测量值范围分别为0.73~1.05μg/L、0.32~0.57μg/L、0.67×10^(-2)~0.95×10^(-2)Bq/L、0.17×10^(-2)~0.37×10^(-2)Bq/L、0.95×10^(-2)~1.31×10^(-2)Bq/L,年待积有效剂量约为0.012 5mSv,该剂量远小于标准限值。

南充市饮用水源地水质总放射性水平分布特征与健康评价

为建立饮用水源地水体放射性水平基线,评估水体辐射安全状况,对2019年南充市9处饮用水源地水质总放射性水平进行了监测,分析了时空变化趋势,并估算了水体核素所致内照射年有效剂量,开展了种群患癌风险评估。结果表明,南充市饮用水源地水质总α、总β活度浓度范围分别为8.4~46.8mBq/L与37.9~168.7 mBq/L,数值时空变化趋势明显,与水体核素自然分布、水质环境、地表径流等因素有关。水体核素所致内照射年有效剂量估算的范围在4.39×10^(-2)~6.86×10^(-2)mSv/a,种群患癌风险几率的范围在2.41×10^(-6)~3.77×10^(-6)。分析得出,水质总放射性水平总体达标,剂量估算水平与患癌风险几率均处于正常水平,其数据可为应对环境突发事件、环境质量评价与水质指标预测评价提供依据。

Measurement of Radon Concentration and Estimation of Cancer Risk in Twenty-Four Model Houses in the Town of Koudougou

The objective of our study is to evaluate the concentration of radon (86Rn) inside houses in the town of Koudougou in order to estimate its impact on the health of the population. Indeed, when uranium-rich minerals are found near the surface of the ground, radon concentrations can reach tens of becquerels per cubic meter in enclosed spaces. Given the nature of the geological base of Burkina Faso, this situation is quite probable and certain places that are sometimes poorly ventilated (house, school, office, etc.) can have radon levels high enough to constitute a health problem for occupants. Thus, twenty-four (24) sample houses were identified. In each house, the Corentium digital detector was between 0.8 m and 2 m for at least one week in a place where the occupants estimate that they spend more time of time and measure the concentration of radon in the long term and short term. The recorded data allowed us to determine the Absorbed Dose and the Annual Effective Dose of radon gas for each house in order to estimate the Risk of Cancer and the probable Number of Cases of Lung Cancer per million inhabitants. Thus, the results indicate that the long-term radon concentration varies between 6 Bq/m3 and 285 Bq/m3 respectively in houses 11 and 4 compared to 1 Bq/m3 to 208 Bq/m3 in the short term in the same houses. Also, in the long term, in control houses 1, 3 and 4, the radon level is above the recommended threshold interval. For the short term, these are houses 1, 3, 4 and 17 respectively with 110 Bq/m3, 142 Bq/m3, 208 Bq/m3 and 105 Bq/m3. As for the long-term and short-term effective doses, only houses 1, 3, 4, 17 and 24 have values between 3 - 10 Sv/year. The estimation of the relative risk of lung cancer gives values relatively close to unity and between 1.006 and 1.142 with an average of 1.035 and that of the Number of Lung Cancer Cases per million inhabitants gives values between 8 and 166 with an average of 42. Thus, we can conclude that with the exception of houses 1, 3, 4 and 17, the radon concentrations are relatively low in the twenty-four control houses in the city of Koudougou. The lifestyle of the populations can well explain this situation when we know that people are in the habit of always leaving doors and windows open, especially when they are not sleeping. We can therefore say that the risk of population exposure to radon gas is relatively low in the town of Koudougou.

通辽市文冠果种仁重金属与放射性测量分析及健康风险评估

目的:为加强对食品的安全监管和推动文冠果产业的可持续发展,测定文冠果种仁的重金属含量,分析文冠果种仁的放射性水平并测量放射性核素的比活度。方法:利用AAS6810火焰原子吸收分光光度计对重金属铜、铬、锰、铅和锌(Cu、Cr、Mn、Pb和Zn)含量进行测量,利用超低本底高纯锗γ能谱仪对放射性核素^(238)U、^(226)Ra、232^(Th)、^(40)K和^(137)Cs的比活度进行测量,利用HY3324型四路低本底α、β测量仪对总α、总β放射性比活度进行测定,以此为依据估算居民膳食摄入所致年有效剂量并进行健康风险评估。结果:文冠果种仁中重金属Cu、Cr、Mn、Pb和Zn的含量依次为0.160 mg·kg^(-1)、0 mg·kg^(-1)、0.026 mg·kg^(-1)、0.018 mg·kg^(-1)、0.733 mg·kg^(-1);放射性核素^(238)U、^(226)Ra、232^(Th)、^(40)K和^(137)Cs的比活度依次为-2.45 Bq·kg^(-1)、-0.91 Bq·kg^(-1)、-0.71 Bq·kg^(-1)、133.56 Bq·kg^(-1)、0.016 Bq·kg^(-1);总α、总β放射性比活度为0 Bq·kg^(-1)、223 Bq·kg^(-1)。结论:文冠果种仁中Cu、Cr、Mn、Pb和Zn的含量都低于食品安全国家标准和食品安全风险监测数据,计算成年人和儿童食用摄入重金属的危害靶标危害系数和综合危害指数均远远小于1,不会对人体产生健康风险;^(238)U、^(226)Ra、232^(Th)、^(40)K和^(137)Cs的比活度远低于国家标准,估算得出居民膳食摄入不同核素所致年有效剂量为3.78×10^(-6)Sv,低于世界公众食入所致内照射平均年剂量;总α、总β放射性比活度在正常水平范围内,可放心食用。

石笋的ESR和U系年龄的对比研究

对北京周口店猿人遗址第四地点洞穴的石笋进行了ＥＳＲ测定，用封闭平衡模式计算了它们的ＥＳＲ年龄，并与Ｕ系年龄进行了对比，发现这两种方法估计的平均年龄十分一致．

Daybreak厚源α-计数仪的标定及测量影响因素的初步研究

年剂量测量是释光和电子自旋共振测年的关键之一。厚源α-计数仪(简称TSAC)是年剂量测量中的常用仪器。通过不同标准源的标定对比实验,对美国Daybreak公司582,583型低本底厚源α-计数仪的高压值(HV)和积分甄别器阈值(DISC)进行了标定。同时,对测量过程中的诸多影响因素如被测样品的氡逃逸、粒度、含水量、颜色以及ZnS闪烁屏的密度、测量时间等开展了初步的实验研究,并根据实验结果提出了针对本型号仪器在实际测量时的改进措施,以提高厚源α-计数仪的测量精度。

青岛市区土壤天然放射性核素的外照射水平估算研究

城市的辐射环境质量对于人居和发展规划有重要意义。利用伽玛能谱仪对青岛市区内的天然放射性核素进行了大规模高密度的现场测量,采用Beck公式计算了离地面1m高处的空气吸收剂量率,进而计算了外照射年有效剂量、外照射指数和等效镭浓度,对研究区的外照射水平进行了系统的评价。与和其他国家全国比较,虽然该区的空气吸收剂量率较高,但是其他衡量天然放射性核素外照射水平的指标均在容许范围之内。因此该区属于外照射水平的安全区域,人居环境不受影响。

青岛市地表伽玛辐射特征及环境影响评价

对青岛市1 500 km2范围内大密度土壤放射性核素和地表γ辐射测量,系统深入研究了其放射性特征、分布规律及其影响因素。结果表明,青岛市土壤中核素232Th和40K的放射性比活度偏高,而238U偏低。地表γ辐射剂量率(平均值91.87 nGy/h)略高于全国和世界平均值。研究发现,地表93.14%的γ辐射来自地面放射性核素238U、232Th和40K的γ辐射,其中232Th和40K的贡献占81.21%,是主要的贡献者。地质背景决定地面γ辐射剂量率值,燕山期各类花岗岩是导致青岛市区—王哥庄一带γ辐射剂量率偏高的主要原因;同时环境因素(路面材料、地貌景观)对其剂量率也存在一定影响。虽然研究区的γ辐射剂量率较高,但其年有效剂量(0.56 mSv)低于公众照射年剂量当量限值(1.0 mSv),人居环境基本不受影响。

方解石的辐照效应和ESR测年法的研究

本文研究了人工合成方解石和天然石笋样品的ESR谱及在α、β、γ射线辐照下的效应。由实验测出的TD和D值,计算出周口店第四地点石笋平均年龄为(6.0±0.8)×10~4年,此值与轴系法测得的平均年龄(6.5±0.4)×10~4年一致。