annual effective dose
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Author(s):  
O. B. Olafisoye ◽  
◽  
O. O. Oguntibeju ◽  
O. A. Osibote

Hyper Pure Germanium (HPGe) radiation detector was used to estimate the activity concentration of fifteen soil and palm oil samples collected from the oil palm plantations in the southwestern, southeastern, and south southern states of Nigeria, and the risk assessments was evaluated. The activity concentrations at a soil depth 0 – 15 cm ranged from 187.4 to 514.4, 2.328 to 6.571, and 1.509 to 6.121 Bq/kg for 40K, 238U, and 232Th, respectively. The activity concentrations at a soil depth 15 – 30 cm ranged from 163.4 to 3188.8, 1.345 to 9.410, and 1.476 to 6.275 Bq/kg for 40K, 238U, and 232Th, respectively. The activity concentrations in the palm oil ranged from 122.3 to 968.0, 1.240 to 6.651, and 1.199 to 8.061 Bq/L for 40K, 238U, and 232Th. For the risk assessments of surface soil samples, the absorbed dose rate (D) ranged from 5.09 to 24.54 nGy/h, while the annual effective dose equivalent (E) ranged from 0.612 × 10-2 to 16.49 × 10-2 mSv/y. The radium equivalent, gamma absorbed dose rate, and the annual effective dose rate in the palm oil samples ranged from 9.981 to 88.00 Bq/L, 4.315 to 46.29 nGy/h, and 0.53 × 10-2 to 56.90 x 10-2 mSv/y, respectively. The activity concentrations reported for soil and palm oil samples were lower than the recommended world average values given by UNSCEAR. Hence, the hazard and risk assessments indicated a low radiation risk within the studied areas.


Author(s):  
Anwar Khadher Mohammed ◽  
Mokhtar Salim Saleh Al_Salimi ◽  
M. I. Ahmed

In this study, the activity concentration of indoor radon-222, annual effective dose, exhalation rate of radon, and relative risk of lung cancer are reported for different indoor buildings (students' dorms, teachers' dorms, offices, laboratories, library, lecture halls, and materials store) in Faculty of Education, Yafea, Aden University, Yemen. Sealed-can technique based on CR-39 nuclear tracks detector was distributed to radon gas survey. Twenty six radon detectors were mounted in seven buildings. The Radon measurements were performed for 90 days between December 2020 and March 2021. The results showed that the radon concentration ranges from 23,18 Bq m-3 to 66.49 Bq m-3 with an average value 35.86 Bq m-3, the annual effective dose ranges from 0.6 mSv y-1 to 1.639 mSv y-1 with an average value 0.979 mSv y-1, the exhalation rate ranges from 10.03 m Bq m-2 h-1 to 28.50 mBq m-2 h-1 with an average value 15.68 mBq m-2 h-1 and relative risk of lung cancer ranges from 1.02 to 1.06 with an average value 1.03. A strong correlation coefficient has been observed between radon concentration and radon exhalation rate. All of the values revealed in the study were of nominal state (that is less than allowed global values) and thus have no risk for the population living in these buildings.


Author(s):  
Mansi Srivastava ◽  
P. K. Srivastava ◽  
Dharmendra Kumar ◽  
Ajay Kumar

Abstract A parametric investigation was carried out to estimate the Uranium concentration and other associated water quality parameters for the groundwater in Deoghar district, Jharkhand. Total 150 groundwater samples have been collected from dig wells, hand pumps, tube wells, etc. for the pre and post-monsoon seasons. A Quantalase Uranium analyzer was used to measure the uranium concentration. The distribution of pH, TDS, DO, nitrate, sulfate, uranium along with the radiation has been determined. It was found that the uranium concentration in groundwater varies from 0.10 to 11.30ppb in pre-monsoon and 0.15–6.50ppb in the post-monsoon which is well below the normal tolerance limit (i.e.30 μg/l WHO). This low availability of Uranium has been attributed due to the existence of a lesser number of rocks containing uranium as a source in that area. An attempt has been made to correlate the uranium concentration with the water quality parameters for both seasons. The correlation data reveals that ORP, nitrate, phosphate, calcium, and magnesium show a positive correlation with uranium concentration for both seasons on the other hand TDS, EC, temperature, DO, fluoride, and chloride show negative correlation. The positive correlation implies that uranium may be present in groundwater as a dissolved salt of these parameters. Comparative studies for the parameters have been done for both the seasons and various factors have been discussed for the occurrence of the same. The annual effective dose associated with the ingestion of uranium by the population of the region has been estimated using USPEA equations.


2021 ◽  
Vol 19 (12) ◽  
pp. 06-10
Author(s):  
Hussam Najem Abood ◽  
Ahmed Abbas Mohamed

Indoor radon/thoron concentration has been determined in some dwellings of Suq Alshouk district in Thiqar Governorate southern of Iraq, using LR-115 type II and CR-39 (SSNTDs). In this work the indoor radon/thoron concentration varies from (8-73) Bq m-3 for radon with an average 35±2Bq m-3, and ranges (1- 47) Bq m-3 for thoron with an average16±2Bq m-3. The average annual effective dose due to radon and thoron varies from 0.43-3.38m Sv y-1 with average value 1.43±0.11 mSv y-1.


2021 ◽  
Vol 14 (4) ◽  
pp. 103-113
Author(s):  
A. N. Barkovsky ◽  
Ruslan R. Akhmatdinov ◽  
Rustam R. Akhmatdinov ◽  
N. К. Baryshkov ◽  
A. M. Biblin ◽  
...  

The article presents estimates of radiation doses of technogenic exposure to personnel and the public due to the normal operation of radiation facilities, exposure to the public due to natural sources and technogenically altered radiation environment, and medical exposure of patients. The doses values were obtained using the Unified System of Individual Dose Control of the Russian Federation citizens for 2020. The authors have analyzed the data contained in the forms of state statistical observation No. 1-DOZ, No. 2-DOZ, No. 3-DOZ and No. 4-DOZ for 2020 submitted by the organizations and territories, the state sanitary and epidemiological supervision of which was carried out by Rospotrebnadzor and Federal Medical Biological Agency of Russia. In the article also were used data obtained within the framework of Radiation-Hygiene Passportization. In 2020, 19 737 organizations dealing with technogenic sources of ionizing radiation submitted forms No. 1-DOZ with the information on the doses to personnel with a total number of 230 318 persons, of which 230 318 persons belonged to the personnel group A and 21 303 persons belonged to the personnel group B. For these groups, the doses were assessed based on results of individual dosimetric control. In 2020, according to Unified System of Individual Dose Control of the Russian Federation citizens data, the average individual annual effective dose of technogenic exposure to the personnel group A was 1.11 mSv, and for the personnel group B it was 0.63 mSv. In 2020, 6 cases of exceeding the average annual effective dose limit (20 mSv) for Group A personnel and 18 cases of exceeding the average annual effective dose limit (5 mSv) for Group B personnel were registered. The total number of X-ray and radiological diagnostic procedures performed in the Russian Federation in 2020 exceeded 275.4 million, or 1.83 procedures per a citizen. The average annual effective dose of medical radiation exposure per one resident of Russia in 2020 was 0.81 mSv, and per procedure – 0.44 mSv. The average annual effective dose of radiation to residents of the Russian Federation from natural sources, according to all measurements for the period from 2001 to 2020, was 3.36 mSv. More than 59% of this dose is associated with the inhalation of radon and its progenies. The average individual annual effective radiation dose to residents the Russian Federation subjects in 2020 ranged from 2.47 mSv (Kamchatka Krai) to 9.06 mSv (Altai Republic) with an average value for the Russian Federation of 4.18 mSv. For eight subjects of the Russian Federation, the average individual annual effective dose to public in 2020 exceeded 5 mSv: the Republics of Buryatia (5.31 mSv), Altai (9.06 mSv), Tyva (6.31 mSv), Magadan (5.07 mSv) and Irkutsk (6.13 mSv) regions, Stavropol (6.31 mSv) and Zabaykalsky (8.19 mSv) krai and the Evreiskaya Autonomous oblast (6.77 mSv).


2021 ◽  
Vol 5 (1) ◽  
pp. 34-51
Author(s):  
E C D K Addison ◽  
R A Opoku ◽  
C E B N Addison ◽  
W I Aniagyei

Purpose: A study was conducted to estimate the Annual Effective Dose Equivalent (AEDE) and Excess Lifetime Cancer Risk (ELCR) caused by the presence of an artificial cobalt-60 radioactive source producing ionizing radiation levels within the radiotherapy facility at Komfo Anokye Teaching Hospital (KATH) in Ghana. This study validated the safety of cobalt-60 radioactive sources, as well as the notion of calculating the Annual Effective Dose Equivalent (AEDE) and Excess Lifetime Cancer Risk (ELCR), which contributed to reducing occupational and public exposures inside the facility. Methodology: The investigation was carried out with the use of a portable OD-01 Ionization Chamber Survey Meter. The absorbed dose rate (ADR) in air was changed between 5 m and 40 m, with measurements taken inside and around the cobalt 60 bunker, as well as at sixteen other sites within the radiation facility. Findings: From 5 m to 40 m surrounding the Cobalt-60 source, the estimated Absorbed Dose Rate in air inside the cobalt-60 bunker ranged from 0.299 0.001 to 0.977 0.005 Sv/h, with an average of 0.498 0.005 Sv/h. The estimated Annual effective dose equivalent varied from 1.100 mSv/yr to 3.595 mSv/yr around the cobalt-60 source inside the Co-60 bunker. Radiation exposure levels ranged from 0.268 0.008 Sv/h to 0.678 0.005 Sv/h, with an average of 0.440 0.004 Sv/h observed around the fifteen sites chosen. Excess Lifetime Cancer has values ranging from 3.85 10-3 to 12.58 10-3 and 3.45 10-3 to 8.73 10-3. Risks were evaluated for the cobalt and the sixteen places inside the plant. The absorbed dose values at 5 m, 10 m, and 15 m inside the Co-60 bunker and the location Co-60 bunker as part of the facility exceeded the ICRP-recommended limit of 0.57. The AEDE and ELCR levels were within the ICRP's acceptable limits. The AEDE and ELCR statistics acquired indicate that the Cobalt-60 unit and its surroundings are radiation safe, although the likelihood of employees contracting cancer from the absorbed dose and background ionizing radiation is significant over a lifetime. Recommendation: However, it is recommended that absorbed dose level monitoring and evaluation of the Radiation Therapy Technologist (RTT) and other workers surrounding the unit be monitored on a regular basis. It is also recommended that Occupational Staff, such as RTTs, spend as little time as possible in the bunker  


Author(s):  
ناصر محمود أحمد ◽  
عباس راشد هاتف ◽  
علاء فالح ◽  
حميزه بنتي قمرالدين

Radon sources can be found in external and internal radiation. Lead pencil (LP) is often used for drawing, sketching, etc. regardless of age nowadays. Paracetamol (PC) is commonly used around the world especially to treat fever, headache, menstrual pain, and common pain. Hence, the aim is to study the procedures for determining the radon gas comes out from different types of lead pencil and paracetamol. Eight and five samples were collected from different companies of lead pencil and paracetamol, respectively. The samples were measured using the sealed technique in cylindrical plastic containers with CN–85 detectors. After irradiation, the detectors were chemically etched using 2 N sodium hydroxide (NaOH) solution at a temperature of 70 ºC for 62 min. The alpha track density on the surface of detectors was measured using an optical microscope at a magnification of 100×. Tracks on detectors were counted using Image software. Radon concentration values including all samples in this study are within the limits of international which is 1000 Bq/m3. The concentration of radium in LP and PC samples are lower than those reported in previous study. The result of the uranium concentration of both samples is quite low compared with the allowed limit which is 11.7 ppm. Annual effective dose levels are all below the dose limit which is 10 mSv/y. Lastly, there was a linear relationship between radium activity and radon exhalation rate. Therefore, using LP and eating PC cause no danger to humans. All results showed in this study are within internationally permissible limits, and therefore not a threat to human health.


2021 ◽  
Vol 19 (11) ◽  
pp. 22-31
Author(s):  
Sawsan Sh. Fleifil ◽  
Zahraa A. Ismail AL-Sudani

In this study, assessment of levels natural radioactivity in drinking water samples of Misan Province of Iraq was carried out. A total of 33 (Tigris river, station and Tap) water samples collected from eleven places in Misan Province of Iraq. The beta and alpha gross radioactivity of the samples water was measured and an average annual effective dose derived of drinking-water ingestion was estimation utilizing new model a LB-4110 low background gas flow proportional counter. The data indicated that the Beta and Alpha gross activities and annual effective dose in samples did not exceed WHO recommended levels (0.5 Bq/L of Alpha gross, 1.0 Bq/L of Beta gross and 0.1 mSv/y for annual effective dose).


2021 ◽  
Author(s):  
Hamid Ramazanian ◽  
◽  
Tareq Alrefae ◽  

Radioactivity in egg was investigated. The targeted radionuclides were the long-lived gamma emitters 228Ra, 226Ra, and 40K. Measurements were carried out using a high purity germanium detector. The calculated annual effective dose due to egg consumption was 79 μSv yr-1, which forms 1/4 of the 290 μSv yr-1 world average ingestion exposure from natural sources. Hence, no radiological hazards exist from egg consumption due to the presence of the investigated radionuclides.


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