Method for calculating the yearly effective dose of external irradiation of the population living in radioactively contaminated territories

Atomic Energy ◽  
1996 ◽  
Vol 81 (3) ◽  
pp. 678-682 ◽  
Author(s):  
E. A. Ivanov

Ionizing radiation gives tremendous benefit to mankind in the hospital through diagnosis and treatment to patients but unnecessary radiation may cause harm to healthcare workers & the public. The purpose of the study is to continuous radiation monitoring in & around the three largest radiological facilities of Bangladesh such as Atomic Energy Centre Dhaka (AECD), Dhaka Medical College Hospital (DMCH) & Bangabandhu Sheikh Mujib Medical University (BSMMU) campuses, and estimation of radiation risk on healthcare workers & public health. Continuous radiation monitoring was performed in & around the AECD, DMCH, BSMMU campuses from August-October 2020 using the Chemiluminescent Dosimeters. The yearly effective doses to healthcare workers and the public due to radiation released from the facilities were ranged from 0.606 ± 0.031 mSv to 0.801 ± 0.0.042 mSv with a mean of 0.707 ± 0.053 mSv. The excess lifetime cancer risk (ELCR) on healthcare workers & public health were evaluated based on the yearly effective dose and ranged from 2.486 Χ 10-3 to 3.287 Χ 10-3 with a mean of 2.900 Χ 10-3. The average yearly effective dose and ELCR on healthcare workers & public health were lower than those of the worldwide permissible values. Continuous radiation monitoring in & around the largest radiological facilities is required for detection of the radiation generating equipment’s malfunctions and improper handling of the radioactive materials. The study would help for minimization of radiation risk on healthcare workers & the public and this keeps the hospital’s environment free from radiation hazard.


Author(s):  
Michal Panik ◽  
Tomas Hrncir ◽  
Vladimir Necas

During the operation and especially during decommissioning of nuclear installation is produced considerable amount of solid materials (metals, non-metals, building structures) that can fix radioactivity in forms of contamination or activation. The materials present radioactive waste, part of radioactive waste may just slightly exceed limits for unconditional release of materials into the environment. On the other side, there is possible, after proving of defined safety limits fulfillment, to conditionally release radioactive waste for special purpose. In opposite case it would be inevitable to dispose radioactive waste in radioactive waste repository. Approaches of different countries to release of materials vary and the extent of this issue processing is related to each approach. Requirements set down in Slovak Republic legislation are given in the paper. Before the conditional release of materials there must be done consistent analysis of the materials impact on the inhabitants and the environment in short and long time period. The analysis comprises the evaluation of considered scenarios of specific utilization of conditionally released materials. This analysis necessarily precedes the realization of utilization. Scenarios describing utilization of radioactive waste carbon steel in the motorway bridge building process is stated in the paper. Radioactive steel can be utilized in many parts of the bridge. In the paper it is described its use as reinforcement of piles. Short time period external irradiation of workers and inhabitants is taken into account. Critical group (i.e. the group that gets the highest accumulated dose) of workers or inhabitants is chosen. Specific mass activity of released radioactive waste carbon steel is related to individual effective dose taken by critical group. Following legislation rules, annual effective dose taken by critical group must not overstep the limit of 10 μSv/year. The determination of value of the specific mass activity is the target of scenarios evaluating. Evaluation of model scenarios can be realized with the appropriate calculation tool. In the paper VISIPLAN 3D ALARA planning tool was chosen.


Proceedings ◽  
2018 ◽  
Vol 2 (10) ◽  
pp. 562
Author(s):  
Carlos Alves ◽  
Jorge Sanjurjo-Sánchez

Rocks and soils are an important source of external gamma radiation due to their content in U, Th, and K. The dose rate derived from the emission of gamma-rays of radioisotopes can be directly measured or assessed from their content. In the present study, values of outdoor gamma radiation absorbed dose rate are analyzed to explore the implications of levels related to those values in terms of the exposure time necessary for attaining a certain yearly effective dose. We propose simple relations with the absorbed dose rate and with the gamma index of materials.


1968 ◽  
Vol 07 (01) ◽  
pp. 28-36 ◽  
Author(s):  
Władysław Jasiński ◽  
Janina Malinowska ◽  
Henryk Mackiewicz ◽  
Henryk Siwicki ◽  
Krystyna Lukawska

SummaryThe purpose of this investigation was to study the accumulation of 87mSr in the proximal parts of the femoral bones of patients treated previously by external irradiation due to cancer of the uterine cervix. It was assumed that this method may be used in the future for the early diagnosis of postirradiation changes of bone (osteoradionecrosis).The incidence of postirradiation changes of the femoral neck among 5735 patients treated between 1950 and 1961 at the Department of Gynaecology of the Institute, was 0.8%. In the early period of postirradiation changes the patients complain only of pain and limitation of physical activities. If radiological and gynaecological findings were negative, the differential diagnosis between early recurrence and early osteoradionecrosis became impossible.49 selected patients were scanned after intravenous injection of 10—115 μCi of 87mSr per kg of body weight (0.5 up to 6.0 mCi). Illustrative cases of normal pelvic bones as well as postirradiation changes are presented and discussed. The authors conclude that the findings justify further systematic studies on the morphology of accumulation of 87mSr in the bones.


1967 ◽  
Vol 06 (02) ◽  
pp. 170-183
Author(s):  
K. Šilink ◽  
J. Němec ◽  
J. Kubal ◽  
S. Röhling ◽  
S. Vohnout

SummaryThe clinical course and the haematologic events in a patient suffering from metastatic thyroid cancer after administration of 806 mCi of 131I are described. A serious bone marrow depression developed and was treated successfully. The haematological changes during the early and late phases of the radiation injury were studied in detail and compared with those after external irradiation. The haematological events after internal irradiation with 131I are characterised by initial neutrophilic leukocytosis, protracted lymphopenia, slowly developing anaemia reaching lowest values about 3 months after administration, erythroid hyperplasia in the bone marrow after recovery from bone marrow depression and prominent cytological features of the bone marrow, especially pronounced erythropoietic polyploidy.


2005 ◽  
Vol 44 (05) ◽  
pp. 119-130 ◽  
Author(s):  
P. Schnell-Inderst ◽  
D. Noßke ◽  
M. Weiss ◽  
A. Stamm-Meyer ◽  
G. Brix ◽  
...  

Summary:The aim of this study was to estimate both the frequency and effective dose of nuclear medicine procedures performed in Germany between 1996 and 2000 for different subgroups of patients. Methods: Electronically archived data from 14 hospitals and 10 private practices were restored and statistically analyzed. The effective dose per examination was calculated according to ICRP publication 80 using the tissue weighting factors given in ICRP publication 60. Based on the data collected, statistical parameters were computed to characterize the frequency and effective dose of the various nuclear medicine procedures. Results: In total, 604,771 nuclear medicine procedures performed in 433,709 patients were analyzed. On average, 1.4 examinations were carried out per patient and year. The median effective dose was 1.7 [5.-95. percentile; mean: 0.4–8.5; 2.9] mSv per examination and 2.3 [0.5–11.2; 3.5] mSv per patient. Interestingly, the mean effective dose per examination, but not the number of examinations per year increased with the age of the patients. Most frequent were examinations of the thyroid (36.7%), the skeleton (27.1%) and the cardiovascular system (11.1%), which were associated with a median effective dose of 0.5 [0.5–1.1; 0.7] mSv, 3.4 [2.9–5.1; 3.6] mSv and 7.3 [3.2–21.0; 9.5] mSv, respectively. Over the five-year period examined, the total annual number of PET procedures (222.3%) as well as of examinations of thyroid (24.5%), skeleton (17.9%), and the cardiovascular system (14.9%) increased markedly, whereas a decrease was observed for brain (-39.3%), lung (-20.2%) and renal (-15.0%) scans. Conclusion: The age- and gender-specific data presented in this study provide detailed public health information on both the current status and recent trends in the practice of diagnostic nuclear medicine examinations.


2002 ◽  
Vol 41 (02) ◽  
pp. 102-107 ◽  
Author(s):  
J. Kopp ◽  
H. Vogt ◽  
F. Wawroschek ◽  
S. Gröber ◽  
R. Dorn ◽  
...  

Summary Aim: To visualise the sentinel lymph nodes (SLNs) of the prostate we injected the radiotracer into the parenchyma of the prostate. The activity was deposited in liver, spleen, bone marrow, urinary bladder and regional lymphatic system. The aim of this work is to determine biokinetical data and to estimate radiation doses to the patient. Methods: The patients with prostate cancer received a sonographically controlled, transrectal administration of 99mTc-Nanocoll®, injected directly into both prostate lobes. In 10 randomly selected patients radionuclide distribution and its time course was determined via regions of interest (ROIs) over prostate, urinary bladder, liver, spleen and the lymph nodes. The uptake in the SLNs was estimated from gamma probe measurements at the surgically removed nodes. To compare tumour positive with tumour free lymph nodes according to SLN-uptake and SLNlocalisation we evaluated 108 lymph nodes out of 24 patients with tumour positive SLN. For calculating the effective dose according to ICRP 60 of the patients we used the MIRD-method and the Mirdose 3.1 software. Results: The average uptake of separate organs was: bladder content 24%, liver 25.5%, spleen 2%, sum of SLN 0.5%. An average of 9% of the applied activity remained in the prostate. The residual activity was mainly accumulated in bone marrow and blood. Occasionally a weak activity enrichment in intestinal tract and kidneys could be recognized. The effective dose to the patient was estimated to 7.6 μSv/MBq. The radioactivity uptake of the SLN varied in several orders of magnitude between 0.006% and 0.6%. The probability of SLN-metastasis was found to be independent from tracer uptake in the lymph node. The radioactivity uptake of the SLNs in distinct lymph node regions showed no significant differences. Conclusion: The radiotracer is transferred out of the prostate via blood flow, by direct transfer via the urethra into the bladder and by lymphatic transport. Injecting a total activity of 200 MBq leads to a mean effective dose of 1.5 mSv. It is not recommended to use the tracer uptake in lymph nodes as the only criterion to characterize SLNs.


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