Investigating the Expression Levels of Bax and Bcl-2 Genes in Peripheral Blood Lymphocytes of Industrial Radiation Workers in the Asaluyeh Region.

Background: Industrial radiography uses gamma or X-ray radionuclide sources to investigate the safety of industrial materials. Industrial radiation workers receive the highest occupational radiation doses. Objective: The present study investigates the relationship between Bax and Bcl-2 gene expression variables in industrial radiation workers. Material and Methods: In this case-control study, data was collected using blood sampling from 40 workers, including two groups of non-radiation and radiation workers employed at the location. Expression levels of Bax and Bcl-2 genes were assessed in the laboratory. The environmental and absorbed doses of workers were measured using environmental and pen dosimeters. Results: Statistical analysis showed that the radiation group's Bcl-2 gene expression level was significantly higher. Findings also demonstrated a correlation between Bcl-2 gene expression and the number of workdays. Also, the Bax gene expression did not show a significant change, and the expression ratio of Bax/Bcl-2 was insignificant in the two groups. Conclusion: Exposure to low doses of radiation could promote an adaptive response in cells by increasing Bcl-2 gene expression.

Physical dose estimation for an accidental exposed person in industrial γ-ray flaw detection / 中华放射医学与防护杂志

Objective:To estimate the physical dose of an over exposed person working for industrial radiography.Methods:The main exposure parameters were obtained. The exposure duration was 8 min. The exposure pattern was external exposure by isotropic point radioactive source. The radioactive activity was 2.183 TBq. In the present calculation, the Chinese reference adult voxel phantom was used, and the Monte Carlo simulation was performed using the program based on the secondary development of Geant4 to obtain the absorbed dose of each part of the victim.Results:The dose distribution in the victim′s hands was obtained. The doses to most areas of the palm were 2-10 Gy, and the doses to the fingers were 10-20 Gy. The equivalent doses to 23 tissues or organs of the exposed person were estimated to be in the range of 0.012-0.207 Gy.Conclusions:The physical dose estimation method could evaluate rapidly the local dose distribution of the victim′s key exposed body parts, and thus provide an important reference for medical treatment.

Simulation of a complete X-ray digital radiographic system for industrial applications.

Simulating X-ray images is of great importance in industry and medicine. Using such simulation permits us to optimize parameters which affect image's quality without the limitations of an experimental procedure. This study revolves around a novel methodology to simulate a complete industrial X-ray digital radiographic system composed of an X-ray tube and a computed radiography (CR) image plate using Monte Carlo N Particle eXtended (MCNPX) code. In the process of our research, an industrial X-ray tube with maximum voltage of 300 kV and current of 5 mA was simulated. A 3-layer uniform plate including a polymer overcoat layer, a phosphor layer and a polycarbonate backing layer was also defined and simulated as the CR imaging plate. To model the image formation in the image plate, at first the absorbed dose was calculated in each pixel inside the phosphor layer of CR imaging plate using the mesh tally in MCNPX code and then was converted to gray value using a mathematical relationship determined in a separate procedure. To validate the simulation results, an experimental setup was designed and the images of two step wedges created out of aluminum and steel were captured by the experiments and compared with the simulations. The results show that the simulated images are in good agreement with the experimental ones demonstrating the ability of the proposed methodology for simulating an industrial X-ray imaging system.

Reconstructive dosimetry for cutaneous radiation syndrome

According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.