Evaluation of natural radioactivity content in high-volume surface water samples along the northern coast of Oman Sea using portable high-resolution gamma-ray spectrometry.

Portable high-resolution gamma-ray spectrometry was carried out to determine the natural radioactivity levels in high volume surface water samples of the northern coast of Oman Sea, covering the coastal strip from Hormoz strait to Goatr seaport, for the first time. The water samples from 36 coastal and near shore locations were collected for analysis. Analyses on the samples collected were carried out to determine (226)Ra, (232)Th and (40)K contents. The concentration of (226)Ra, (232)Th and (40)K in surface water samples ranged between 2.19 and 2.82 Bq/L, 1.66-2.17 Bq/L and 132.6-148.87 Bq/L, respectively. The activity profile of radionuclides shows low activity across the study area. The study also examined some radiation hazard indices. The external hazard index was found to be less than 1, indicating a low dose. The results of measurements will serve as background reference level for Oman Sea coastlines.

Natural radionuclides tracing in marine surface waters along the northern coast of Oman Sea by combining the radioactivity analysis, oceanic currents and the SWAN model results.

This study aims to establish a managed sampling plan for rapid estimate of natural radio-nuclides diffusion in the northern coast of the Oman Sea. First, the natural radioactivity analysis in 36 high volume surface water samples was carried out using a portable high-resolution gamma-ray spectrometry. Second, the oceanic currents in the northern coast were investigated. Then, the third generation spectral SWAN model was utilized to simulate wave parameters. Direction of natural radioactivity propagation was coupled with the preferable wave vectors and oceanic currents direction that face to any marine pollution, these last two factors will contribute to increase or decrease of pollution in each grid. The results were indicated that the natural radioactivity concentration between the grids 8600 and 8604 is gathered in the grid 8600 and between the grids 8605 and 8608 is propagated toward middle part of Oman Sea.

235U, 238U, 232Th, 40K and 137Cs activity concentrations in marine sediments along the northern coast of Oman Sea using high-resolution gamma-ray spectrometry.

The natural radioactivity levels in sediment samples of the northern coast of Oman Sea, covering the coastal strip from Hormoz canyon to Goatr seaport, as the first time has been determined. The results of measurements will serve as background reference level for Oman Sea coastlines. Sediments from 36 coastal and near shore locations were collected for analysis. Analysis on the collected samples were carried out to determine (235)U, (238)U, (232)Th, (40)K and (137)Cs using two high purity germanium detectors with 38.5% and 55% relative efficiencies. The concentration of (235)U, (238)U, (232)Th, (40)K and (137)Cs in sediment samples ranged between 1.01 and 2.87 Bq/kg, 11.83 and 22.68 Bq/kg, 10.7 and 25.02 Bq/kg, 222.89 and 535.07 Bq/kg and 0.14 and 2.8 Bq/kg, respectively. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose.

Development of a new pollution index for heavy metals in sediments.

This study aims to investigate the pollution rate of heavy metals on the western seaboard of Bandarabbas in southeast Iran using a new pollution index. The bulk of the analysis was conducted on sediments, followed by selection of a few samples to perform experiments on chemical partitioning studies as well as biological accessibility. On this basis, the proportions of natural and anthropogenic elements were calculated. Finally, with regard to chemical separation results, the pollution rate was calculated based on Muller's geo-chemical index, enrichment factor, pollution index, and a new "Risk" index. Chemical separation showed the anthropogenic origin of elements are as follows: Ni(27.5%) > Zn(6.5%) > Pb(2%) > Al (0.2%). The newly developed pollution index is indicative of "low environmental pollution "for Ni.