Measurement of ambient dose rates in tantalite mining sites in Oke ̶ Ogun, southwest, Nigeria

2021 ◽  
Vol 20 (2) ◽  
pp. 1-12
Author(s):  
A.E. Ajetunmobi ◽  
S.K. Alausa ◽  
J.O. Coker ◽  
T.W. David ◽  
A.T. Talabi
Keyword(s):  
Cancer Risk ◽  
Ionizing Radiation ◽  
Dose Rate ◽  
Health Effect ◽  
Radioactive Material ◽  
Annual Dose ◽  
Mining Sites ◽  
Dose Rates ◽  
Safe Limit ◽  
Ambient Dose

The work scenarios involved in the mining of tantalite a radioactive material expose the miners to ionizing radiation from the ore and the surrounding environment. The dose level in the mine air may be higher than the safe limit due to various contributory sources of ionizing radiation such as radionuclides from rocks, effluents, sand, and radon gas that emanates from caves and this can be of health detriment to the miners. Measurements of ambient dose rates in four selected mining sites have been investigated. Gamma absorbed dose rates were measured in air onsite at Komu, Sepenteri, Gbedu, and Eluku mining sites in Oke-Ogun areas of Oyo State, Nigeria using GammaRAE II dosimeter. Radiation dose to risk software was used to estimate the cancer risk for the period the miners spent onsite. The measured mean dose rate at the sites falls within the range of (19-240) nSv/y and the estimated annual dose rate, cumulative dose, and cancer risk fall within the range of (37-314) μSv/y, (4.0 ̶ 11.1) mSv and (0.5 ̶ 4.5) E-04 respectively. The upper limits of the range for the radiological parameters are all above the safe limit. The health implication of that is that increased work activities at these mining sites may over the years have a negative health effect on the miners. The exposure time of workers can be reduced through proper planning of working shifts for the miners.

scholarly journals Radiation Exposure of Personnel Categories at the Center of Oncology and Hematology at Mohammed VI Hospital in Marrakech

2019 ◽  
pp. 1-7
Author(s):  
Bouchra Amaoui ◽  
Abdennasser El Kharras ◽  
Mohammed Aabid ◽  
Oum Keltoum Hakam ◽  
Abdelmajid Choukri ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Dose Rate ◽  
Treatment Time ◽  
Radiological Protection ◽  
Average Dose ◽  
Annual Dose ◽  
Overall Treatment Time ◽  
Dose Rates ◽  
Average Value ◽  
Regulatory Standards

Objective: This study aims to estimate the annual doses for personnel categories following their exposure to ionizing radiation during their occupation in the external radiotherapy department of the Center of Oncology and Hematology (COH) at Mohammed VI Hospital in Marrakech. Materials and Methods: Operational dosimeters PACK MGP DMC 3000 were used to measure the dose rates around the machines operating with ionizing radiation. In order to assess the reliability of the measurements made by these dosimeters, they were checked against measurements made at the same position by the Inspector detector. The annual effective dose was calculated by multiplying the average dose rate measured during a procedure by the overall treatment time throughout a year. Results: Regarding the reliability check of the measuring instrument, the recorded error is between 2 and 10% with an average of 7%. For personnel category A, the measured dose rate ranges from 0.066 to 0.083 µSv/h, with an average value of 0.075 µSv/h. For category B, it varies between 0.066 and 0.083 µSv, with an average value of 0.092 µSv/h. It is 0.074 µSv/h for category C. The annual dose for category A ranges from 0.089 to 0.113 mSv/year, with an average value of 0.101 mSv/year. For category B, it varies between 0.089 and 0.113 mSv/year, with an average value of 0.100 mSv/year. It is 0.100mSv/year for category C. Conclusion: The annual effective doses to personnel categories, assessed by this study, are very low compared to the regulatory standards set by the International Commission on Radiological Protection (ICRP). As a result, workers benefit from good radiation protection conditions within the Center of Oncology and Hematology at Mohammed VI Hospital in Marrakech.

Assessment of ionizing radiation exposure levels and associated health risk in some selected solid mineral mining sites Edo-North, Nigeria

2021 ◽  
Vol 19 (3) ◽  
pp. 153-166
Author(s):  
A.O. Eshiemomoh ◽  
G.O. Avwiri ◽  
C.P. Ononugbo
Keyword(s):  
Cancer Risk ◽  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Dose Rate ◽  
Exposure Rate ◽  
Lifetime Cancer Risk ◽  
Entire Study ◽  
Mining Sites ◽  
The Mean ◽  
Ionizing Radiation Exposure

Ionizing radiation exposure rate and its associated health risks were assessed using Digilert 200 and Rados Radiation Monitoring Meter, integrated with Geographical Positioning System (Garmin GPSMAP 76S) of some selected solid mineral mining sites across Edo-North Nigeria. The mean exposure rates show some characteristic range of 0.010±0.005 𝑚𝑅ℎ𝑟−1 to 0.027 𝑚𝑅ℎ𝑟 −1 across the entire study. The obtained mean exposures rates at all the mining pits were higher than the ICRP standard limit of 0.013 𝑚𝑅ℎ𝑟 −1 , except at freedom limestonesmining pit where we recorded 0.010 mRh-1. It was also observed that limestones mining sites exhibited low exposure rate while granite mining sites exhibited high exposure rate. The computed equivalent dose rate ranges from 1.049 mSvy-1 to 2.287 mSvy-1 , which is well above the recommended permissible limit of 1.0 mSvy-1 for the general public. 91.7% of the mining sites recorded higher absorbed dose rate but the mean AEDE recorded across the entire study area are below the ICRP standard. The average excess lifetime cancer risk shows variation from 0.472 x 10-3 to 1.27 x 10-3 . . By this result, the probability of contacting cancer due to radiation exposure is higher in places like Cinoma pit, Cetraco pit, Niger-Cat pit, Jigom pit, Oaries pit and Petra-Quarries pit. Keywords: Assessment, Mining pits, Background, Exposure, lifetime cancer risk

scholarly journals Investigation of dose-rate effects and cell-cycle distribution under protracted exposure to ionizing radiation for various dose-rates

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Yusuke Matsuya ◽  
Stephen J. McMahon ◽  
Kaori Tsutsumi ◽  
Kohei Sasaki ◽  
Go Okuyama ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Ionizing Radiation ◽  
Dose Rate ◽  
Cell Cycle Distribution ◽  
Dose Rates ◽  
Dose Rate Effects ◽  
Rate Effects

Cemented Containers Radiological Data From a Disused Uranium Mine Low-Level Waste Repository: A Calculated-Experiment Cross-Check for Data Verification and Validation

2003 ◽  
Author(s):  
D. G. Cepraga ◽  
G. Cambi ◽  
M. Frisoni ◽  
D. Ene
Keyword(s):  
Experimental Data ◽  
Dose Rate ◽  
Measured Data ◽  
Radioactive Material ◽  
Uranium Mine ◽  
Low Level ◽  
Dose Rates ◽  
Waste Repository ◽  
Central Plan ◽  
Decay Gamma

Code validation problems involve calculation of experiments and a comparison experiment-calculation. Experimental data and physical properties of these systems are used to determine the range of applicability of the validation. Once a sequence-code of calculations has been validated, it has to be underlined that the comparison experimental-calculated results involving “complex systems” or “complex experimental measures” permits also a bi-lateral cross-check between the calculation scheme and the experimental procedures. The results of the testing and the validation effort related to the collection of information and measured data and the comparison between code results with experimental data coming from a “low-level waste” repository are presented in this paper. The Baita-Bihor repository, sited into former disused uranium mine in Transylvania, has been considered as the source of experimental data. The study was developed through the following steps: a) collection and processing of measured data (radioactivity content and dose rate), from the cemented containers of the Baita-Bihor repository; b) decay gamma source calculation by the ANITA-2000 code package (the input data for the calculations are the measured isotope activities for each container); c) decay gamma transport calculation by the SCALENEA-1 shielding Sn sequence approach (Nitawl-Xsdrnpm-Xsdose modules of the Scale 4.4a code system, using the Vitenea-J library, based on FENDL/E-2 data) to obtain dose rates on the surfaces and at various points outside the containers; d) comparison experimental-calculated dose rates, taking into account also the measurement uncertainties. The new version of the ANITA-2000 activation code package used makes possible to assess the behaviour of irradiated materials independently from the knowledge of the irradiation scenario but using only data on the isotope radioactive material composition. Radioactive waste disposed of at Baita Bihor repository consists of worn reactor parts, resins and filters, packing materials, mop heads, protective clothing, temporary floor coverings and tools, the sources normally generated during the day-to-day operation of research reactors, the remediation-treatment stations and the medicine and biological activities. The low and intermediate wastes are prepared for shipping and disposal in the treatment stations by confining them in a cement matrix inside 220 litre metallic drums. Each container consists of an iron cladding filled by concrete Portland. Radioisotope composition and radioactivity distributions inside the drum are measured. The gamma spectroscopy has been used for. The calibration technique was based on the assumption of a uniform distribution of the source activity in the drum and also of a uniform sample matrix. Dose rate measurements are done continuously, circularly, in the central plan on the surface of the drum and 1 m from the surface, in the air. A “stuffing factor” model has been adopted to simulate, for the calculation, the spatial distribution of the gamma sources in the concrete region. In order to guarantee a complete Quality Assurance for codes and procedures, a simulation of the radioactive containers to evaluate the dose rates was done also by using the Monte Carlo MCNP-4C code. Its calculation results are in a very good agreement with those obtained by the Sn approach (discrepancies are around 2%, using the spherical approximation).

EVALUATION OF INDOOR/OUTDOOR GAMMA EXPOSURE RATES AND EXCESS LIFE TIME CANCER RISK IN DIFFERENT CITIES OF PAKISTAN

2020 ◽  
Vol 190 (4) ◽  
pp. 355-363
Author(s):  
Jahan Zeb ◽  
Mohammad Wasim ◽  
Muhammad Awais ◽  
Asad Ullah ◽  
Talat Iqbal ◽  
...  
Keyword(s):  
Cancer Risk ◽  
Dose Rate ◽  
Absorbed Dose ◽  
Life Time ◽  
Absorbed Dose Rate ◽  
Detailed Measurement ◽  
Dose Rates ◽  
The Mean ◽  
Azad Kashmir ◽  
Indoor And Outdoor

Abstract This study presents a detailed measurement of indoor and outdoor terrestrial gamma radiation levels in different cities of Pakistan. The measurements covered dwellings in 27 cities, covering all provinces and region of Azad Kashmir. Most of the houses were of attached type, made of brick walls and concrete roofs. The measurements were made by a handheld radiation survey meter containing Geiger–Muller tube. The average absorbed dose rate in air was 100 ± 32 nGy h−1 for indoor and 74 ± 30 nGy h−1 for outdoor. The population-weighted mean terrestrial dose rates were 90 nGy h−1 for indoor and 78 nGyh−1 for outdoor. The ratio of indoor to outdoor absorbed dose rate was 1.5 as compared to 1.3 for the world average. The estimated average annual effective dose rate was 0.58 ± 0.18 mSv a−1 and the mean excess life time cancer risk was 2.0 × 10−3.

"Subacute" course of chronic radiation syndrome

2021 ◽  
Vol 61 (9) ◽  
pp. 572-579
Author(s):  
Irina A. Galstyan ◽  
Nelya A. Metlyaeva ◽  
Mikhail V. Konchalovsky ◽  
Vladimir Yu. Nugis ◽  
Olga V. Shcherbatykh ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Dose Rate ◽  
Chronic Exposure ◽  
Prolonged Exposure ◽  
Production Factor ◽  
Clear Understanding ◽  
Dose Rates ◽  
Chronic Radiation ◽  
Radiation Material

Introduction. The use of ionizing radiation as a production factor in the late 1940s - early 1950s. began in the absence of a clear understanding of the permissible radiation doses for workers, as well as knowledge of diagnostic criteria and developed therapeutic measures for developing chronic radiation sickness (CRS). Since then, a great deal of experience has been accumulated in the diagnosis and treatment of CRS. Currently, there are no conditions at the workplace for chronic exposure of workers in doses exceeding the permissible ones. However, taking into account the constant expansion of the scope of using sources of ionizing radiation, it is necessary to remember about the possibility of CRS development due to prolonged exposure in case of violation of their storage or their loss. The study aimed to explore the formation of radiation bone marrow syndrome (RBS) due to chronic exposure in doses that exceed the maximum permissible, accumulated with different dose rates of radiation. Material and methods. We selected the medical records of 27 people (24 men and 3 women) who had RBS as a result of chronic professional gamma radiation exposure. The selection criteria were the diagnosis of grade II-III chronic radiation syndrome (CRS) in the presence of agranulocytosis or anemic syndrome in the period of the disease formation and, especially, in the development of myelodysplastic syndrome (MDS) or aplastic anemia in the period of the CRS consequences. Identified clinical and dosimetric CRS features of 27 patients exposed to chronic irradiation with a dose rate of 0.0002-0,009 Gy/h and the summary dose of 1.7 and 9.6 Gy, accumulated over a period of 6 to 96 months were compared the characteristics of 84 patients CRS exposed a lower dose rates (less than 0,0003 Gy/h) and 26 patients with acute radiation syndrome moderate (II) severity as a result of irradiation the dose rates of 0.14-3,7 Gy/h, total dose of 2 to 4 Gy. Results. The criteria of atypical subacute CRS course are identified: the rate of chronic radiation exposure - not less than 0.001-0.009 Gy/h with a summary dose of 1.7-9.6 Gy accumulated over a period of 6-96 months, the presence of agranulocytosis in the period of CRS formation and anemic syndrome in the periods of CRS formation and outcomes. These signs predict the development MDS in 60% of the patients in the period of the CRS consequences. Conclusion. Retrospective study determined that long-term human exposure to a dose rate of 0.001-0,009 Gy/h (0,005-0,05 Gy/day) and more in the accumulation of a summary dose of 1.7 and 9.6 Gy and duration of contact 6-96 months in 60% of cases can be expected development CRS with a subacute clinical course RBS. The main factor determining this feature of the course of RBS is the dose rate exceeding 0.001 Gy / h (2 Gy/year). In the subacute course of CRS, the early outcome in MDS is essentially deterministic. The development of agranulocytosis and anemic syndrome are typical signs of the subacute course of CRS.

scholarly journals EXPOSE-R cosmic radiation time profile

2014 ◽  
Vol 14 (1) ◽  
pp. 17-25 ◽  
Author(s):  
Tsvetan Dachev ◽  
Gerda Horneck ◽  
Donat-Peter Häder ◽  
Martin Schuster ◽  
Michael Lebert
Keyword(s):  
Ionizing Radiation ◽  
Dose Rate ◽  
Cosmic Radiation ◽  
Radiation Belt ◽  
Absorbed Dose ◽  
Galactic Cosmic Rays ◽  
Time Profile ◽  
Outer Radiation Belt ◽  
Dose Rates ◽  
Absorbed Dose Rates

AbstractThe aim of the paper is to present the time profile of cosmic radiation exposure obtained by the radiation risks radiometer-dosimeter (R3DR) during the ESA exposition facility for EXPOSE-R mission (EXPOSE-R) in the EXPOSE-R facility outside the Russian Zvezda module of the International Space Station (ISS). Another aim is to make the obtained results available to other EXPOSE-R teams for use in their data analysis. R3DR is a low mass and small dimensions automated device, which measures solar radiation in four channels and in addition cosmic ionizing radiation. The main results of cosmic ionizing radiation measurements are: three different radiation sources were detected and quantified: galactic cosmic rays (GCR), energetic protons from the inner radiation belt (IRB) in the region of the South Atlantic anomaly and energetic electrons from the outer radiation belt (ORB). The highest daily averaged absorbed dose rate of 506 μGy day−1 came from IRB protons; GCR delivered much smaller daily absorbed dose rates of 81.4 μGy day−1 on average, and ORB source delivered on average a dose rate of 89 μGy day−1. The IRB and ORB daily averaged absorbed dose rates were higher than those observed during the ESA exposition facility for EXPOSE-E mission (EXPOSE-E), whereas the GCR rate was smaller than that measured during the EXPOSE-E mission. The reason for this difference is much less surrounding constructions shielding of the R3DR instrument in comparison with the R3DE instrument.

scholarly journals Comparative analysis of gamma dose rates measured by ion chamber in and around the historical sacral objects in Bosnia and Herzegovina

2019 ◽  
Vol 34 (2) ◽  
pp. 157-164
Author(s):  
Senada Avdic ◽  
Adnan Beganovic ◽  
Armin Lagumdzija ◽  
Samra Sadikovic ◽  
Beco Pehlivanovic ◽  
...  
Keyword(s):  
Dose Rate ◽  
Bosnia And Herzegovina ◽  
Building Materials ◽  
Dose Equivalent ◽  
Late Medieval ◽  
Dose Rates ◽  
Ion Chamber ◽  
Ambient Dose Equivalent ◽  
Ambient Dose ◽  
Indoor And Outdoor

The main objective of this study was to investigate the correlation between the indoor and outdoor ambient dose equivalent rates measured by the ion chamber inside and around the historical sacral objects at a few locations in Bosnia and Herzegovina. The investigated objects made of the traditional building materials were built in the Late Medieval, Post Medieval, and Ottoman Period of Bosnia and Herzegovina history. The LUDLUM Model 9DP instrument based on a pressurized ion chamber was selected for natural low level radiation measurements since the ionisation chambers have higher sensitivities than the other types of detectors. The detection capability of the LUDLUM Model 9DP pressurized ion chamber was examined in the laboratory conditions with a source of low activity and under natural environmental radiation conditions by measuring the indoor and outdoor dose rates. A weak positive correlation was found between the ambient dose equivalent rates inside the historical sacral objects and the dose rates outside the objects. The average evaluated value of the indoor to outdoor dose rate ratio of 1.07 for the studied historic objects is less than that obtained for the contemporary building materials such as concrete. No study on the indoor to outdoor dose rate ratio in Bosnia and Herzegovina measured by the LUDLUM 9DP dose rate meter based on an ion chamber has been conducted yet. In addition to direct measurements, the first gamma spectrometric analysis of a few samples of building materials from the Late Medieval period in Bosna and Herzegovina was performed. The results of the gamma analysis revealed almost uniform distribution of primordial radionuclides in the investigated samples. It was demonstrated that such materials had the reduced content of radioactive isotopes compared to the contemporary building materials and therefore they could have potential advantages in specific applications related to the environmentally sustainable architecture.

ASSESSMENT OF RADIATION EXPOSURE LEVEL IN BLACKSMITHING WORKSHOP IN GOMBE, GOMBE STATE

2021 ◽  
Vol 4 (4) ◽  
pp. 19-25
Author(s):  
Abiodun Olanrewaju ◽  
Nurudeen Mohammed AbdulKareem ◽  
Isiaka O. Raheem
Keyword(s):  
Cancer Risk ◽  
Ionizing Radiation ◽  
Absorbed Dose ◽  
Organ Dose ◽  
Outdoor Exposure ◽  
Exposure Level ◽  
Lifetime Cancer Risk ◽  
Dose Rates ◽  
Excess Lifetime Cancer Risk ◽  
Line Section

Measurement of terrestrial background ionizing radiation of blacksmith workshops of Gombe State, Nigeria was carried out using well-calibrated Geiger-Muller counter meters and a meter tape. The measured average exposure rate of two line-sections are 0.018±0.002 and 0.017±0.002 mRh-1. Estimated equivalent dose rates for the two line-sections are 1.50 and 1.45 mSvy-1. The average absorbed dose rates estimated in line-section one and line-section two are 154.94 and 149.97 nGyh-1 respectively. Annual effective dose equivalent (AEDE) of 0.48 mSvy-1 was obtained for outdoor exposure in line-section one while in line-section two, AEDE was 0.23 mSvy-1. The calculated mean excess lifetime cancer risk values for the blacksmith workshop sections are 0.83x 10-3 and 0.80 x 10-3. The obtained values for background ionizing radiation in the line-sections of blacksmith workshop were above the recommended standard limit by ICRP while the absorbed doses (D) were above the recommended value and AEDE calculated in two line-sections of blacksmithing workshops were within the safe values this implies that blacksmithing activities in these areas may not influence the doses received by public. The excess lifetime cancer risk (ELCR) estimated were higher than their world permissible values of 0.29 x 10-3 respectively. The calculated dose to organs showed that the testes have the highest organ dose of 0.153 mSvy-1while liver has the lowest organ dose of 0.086 mSvy-1. This result shows that exposure to 

Radiation exposure around patients after administration of 123I-MIBG

2002 ◽  
Vol 41 (05) ◽  
pp. 221-223
Author(s):  
S. Ofluoglu ◽  
J. Preitfellner ◽  
B. J. Fueger ◽  
T. Traub ◽  
C. Novotny ◽  
...  
Keyword(s):  
Radiation Exposure ◽  
Dose Rate ◽  
Half Life ◽  
Maximum Dose ◽  
Radiation Detectors ◽  
Mibg Scintigraphy ◽  
Dose Limit ◽  
Annual Dose ◽  
Dose Rates ◽  
M 12

SummaryAim: Estimation of the radiation exposure to neighbouring patients, personnel and relatives deriving from patients undergoing 123I-MIBG scintigraphy. Methods: For scintigraphic studies, 16 patients with suspected pheocromocytoma were injected with 340 ± 30 MBq 123I-MIBG. Dose rates were measured at a distance of 0.5 m, 1 m, and 2 m after 10 min, 3 h, 21 h, 45 h, and 68 h using three calibrated portable radiation detectors. The measured values were background corrected. Results: Ten minutes after injection the dose rate was 10.5 µS/h at a distance of 0.5 m, 3.78 µS/h at 1 m, and 0.95 µS/h at 2 m. The effective half-life was estimated to 8.68 ± 0.15 h. The maximum dose in a distance of 1 m for neighbouring patients was 46 µS/h, for personnel in a ward 27 µS/h, and to relatives in a distance of 2 m 12 µS/h. Conclusion: This study demonstrates that the calculated exposure to people around patients after 123I-MIBG injection is well below the maximum permissible annual dose limit of 1 mSv for not professionally exposed persons.

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