Attachment rate characteristics of different wide used aerosol sources in indoor air.

In this work, six different aerosol sources, used in everyday life, were investigated to analyze parameters such as concentration, size distributions, and dynamics: regular and electronic cigarettes, incense, candles, mosquito coils, and cooking. During the experiments, the aerosol particle count ranged from 200 to 2·105 cm-3. The number, mass, and specific surface area of the aerosol size distributions were measured by a Model 2702 M diffusion aerosol spectrometer (DAS) with a range of 5 nm to 10 µm. The attachment rate of radon decay products to aerosol particles is calculated depending on their size distribution/ The use of household sources of aerosols (heat treatment of food, smoking, candles, etc.) result in an increase in the concentration of aerosol particles by more than an order of magnitude, mainly due to the generation of ultrafine aerosols with number median diameter 64-92 nm and GSD 1.45-1.84. The mass distribution is dominated by particles with a distribution maximum in the range of 2-5 µm. The attachment of radon decay products to aerosols is associated with ultrafine particles with diameter < 200 nm. The median diameter of the rate of attachment to aerosols is 130 nm.

The presence of radioactive heavy minerals in prospecting trenches and concomitant occupational exposure.

Uranium, perhaps the most strategically important component of heavy minerals, finds particular significance in the nuclear industry. In prospecting trenches, the radioactivity of 238U and 232Th provides a good signature of the presence of heavy minerals. In the work herein, the activity concentrations of several key primordial radionuclides (238U, 232Th, and 40K) were measured in prospecting trenches (each of the latter being of approximately the same geometry and physical situation). All of these are located in the Seila area of the South Eastern desert of Egypt. A recently introduced industry standard, the portable hand-held RS-230 BGO gamma-ray spectrometer (1024 channels) was employed in the study. Based on the measured data, the trenches were classified as either non-regulated (U activity less than 1000 Bq kg-1) or regulated (with 238U activity more than 1000 Bq kg-1). Several radiological hazard parameters were calculated, statistical analysis also being performed to examine correlations between the origins of the radionuclides and their influence on the calculated values. While the radioactivity and hazard parameters exceed United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) guided limits, the mean annual effective doses of 0.49 and 1.4 mSv y-1 in non-regulated and regulated trenches respectively remain well below the International Commission on Radiological Protection (ICRP) recommended 20 mSv/y maximum occupational limit. This investigation reveals that the studied area contains high uranium content, suitable for extraction of U-minerals for use in the nuclear fuel cycle.

Dosimetry Assessment of Injected 89Zr-Labeled Monoclonal Antibodies in Humans.

In this study, the behavior dynamics of Zirconium-89 (89Zr)-labeled monoclonal antibodies (MAbs) after injection into the human body were modeled. This modified biokinetic model can be used for dose assessment, not only for 89Zr-labeled MAb tumor visualization, but also for diagnostic and therapeutic radiation with MAb labeled with other radionuclides. A modified biokinetic model was created based on experimental data from previously published studies. Cumulative 89Zr activity in organs and tissues per Bq of administered activity was calculated using the WinAct program. For most organs receiving the highest radiation dose, average absorbed doses were estimated using IDAC version 2.1 software. The results from the modeled calculations were compared with recently published results from studies of real patients. The calculations revealed that organs with the highest dose were the spleen, liver, kidneys and red bone marrow, at 1.54, 1.33, 0.81 and 0.82 mGy/MBq, respectively. In the modified biokinetic model, with MAb injection, organs exhibiting the highest dose were liver, heart wall, spleen, red bone marrow and pancreas, at 1.05, 0.93, 0.79, 0.69 and 0.67 mGy/MBq, respectively.