Radiological Investigation on Sediments: A Case Study of Wadi Rod Elsayalla the Southeastern Desert of Egypt

The presence of heavy radioactive minerals in the studied granitoids from which the Wadi sediments leads to the study of the exposure to emitted gamma rays from the terrestrial radionuclides, such as 238U, 232Th, and 40K. The geological study revealed that the Wadi sediments derived from the surrounding granitoids, such as syenogranite, alkali feldspar granite, and quartz syenite. The mineral analysis confirmed that the granitoids were enriched with radioactive minerals, such as uranothorite as well as monazite, zircon, yttrocolumbite, and allanite. The mean activity of the 238U, 232Th, and 40K concentrations are 62.2 ± 20.8, 84.2 ± 23.3, and 949.4 ± 172.5 Bq kg−1, respectively, for the investigated Wadi sediments, exceeding the reported limit of 33, 45 and 412 Bq kg−1, respectively. Public exposure to emitted gamma radiation is detected by estimating many radiological hazard indices, such as the radium equivalent content (Raeq), external and internal hazard indices (Hex and Hin), annual effective dose (AED), annual gonadal dose equivalent (AGDE), and excess lifetime cancer (ELCR). The obtained results of the radiological hazards parameters showed that public exposure to emitted gamma radiation can induce various dangerous health effects. Thus, the application of the investigated sediments in different building materials and infrastructures fields is not safe. A multivariate statistical analysis (MSA) was applied to detect radionuclide correlations with the radiological hazard parameters estimated in the granite samples.

Radiation dose risk variability and its implication in industrial and mining regions, NW Nigeria

The study area located in the southern part of Kebbi State, northwestern Nigeria, has witnessed intense mining activities and upscale industrialization in recent years. These events have necessitated deeper and insightful studies into radiological hazard evaluation to mitigate associated adverse consequences and enforce protective measures in the environment. A total of 45 sampled locations each were taken for both industrial and mining sites in northwestern Nigeria to determine the concentration of Potassium-40, Thorium-232 and Uranium-238 radionuclides as applied to radiological hazard analysis. The mean value of the absorbed dose in the industrial site was 90 nGy/h, whereas the mining site recorded a mean value of 210 nGy/h. Other radiological indices such as radium equivalent factor, external risk assessment, internal index and representative gamma index recorded mean values of 187.68, 0.507, 0.547 and 0.768 respectively, whereas the same hazard indices presented higher values of 412.58, 1.114, 1.231 and 1.675 respectively in the mining site. The variability studies showed that the dose risk ratio of the industrial region to the mining region is 1:2. The mining site presented radiological hazard indices higher than the recommended global threshold hence should be classified as a restricted zone to forestall health-related crises which may manifest among local dwellers.

Levels of Elements in Typical Mussels from the Southern Coast of Africa (Namibia, South Africa, Mozambique): Safety Aspect

The soft tissues of mussels are often used as the main food source, especially in coastal areas. Neutron Activation Analysis was used to measure the content of 24 macro- and microelements in the soft tissues and 18 elements in the shells of selected sets of mussels of the species Mytilus galloprovincialis. The mussels were collected in 8 polluted and 4 pristine zones, which included Namibia, the west and east coasts of South Africa, and Mozambique. According to factor analysis Co, Ni, Zn, As, Se, Br, I, Sb could have anthropogenic origin. The concentrations of elements such as Cr, As, Se and partly Zn at polluted stations were above the maximum permissible levels for seafood. The concentrations of Sc, V, Cr, Mn, Co, Ni, Sb, Cs, Th, U in shells and soft tissues of the same mussels were at the close levels. Elements such as Al, Cr, Co, As (partly Zn, Se, and I) are considered to be harmful to human health at the levels of mussels consumption of 200 g/week per person and lower in such zones as Swakopmund, East London, Port Shepstone, Richards Bay, Xai-Xai according to calculated risk quotients and target hazard indices.

Assessment of Environmental Radioactivity in Soil Samples from Kathmandu Valley, Nepal

This study was conducted to determine the amount of naturally occurring radioactivity in the soil of Nepal's Kathmandu valley. The activity of naturally occurring radionuclides was determined in these soil samples using a sodium iodide detector. Activity concentrations of 238U, 232Th, and 40K were found in the range: 32.00-111.38 Bq kg-1, 33.52-130.04 Bq kg-1, and 342.50-897.71 Bq kg-1, respectively. These values are well within the permissible range as recommended by UNSCEAR. The soil samples with the highest activity concentrations were primarily found in the valley's northern region. The activity concentrations were also used to calculate the radiation hazard indices: the mean value obtained were 96.63 nGy hr-1 for Absorbed Gamma Dose Rate in Air, 200.04 Bq kg-1 for Radium Equivalent Activity, the 0.12 mSv yr-1 for Annual Effective Dose, and 0.55 for External Hazard Index. These calculated hazard indices were used to estimate the potential radiological health risk from the soil, and the dose rates associated with it were significantly less than their permissible limit. The overall findings indicate no radiological threat to the population's health in the study area. Additionally, the findings of this study provide baseline information on potential radionuclides that contribute mostly for radiation exposure from natural sources.

Spatial distribution and contamination assessment of heavy metal pollution of sediments in coastal reclamation areas: a case study in Shenzhen Bay, China

Background With the continuous advancement of global urbanisation, humans have begun to overutilise or improperly utilise the natural resources of bay areas, which has led to a series of ecological and environmental problems. To evaluate the spatial distributions and potential ecological risks of heavy metals in sediments of Shenzhen Bay, China, an analysis of As, Cd, Cr, Cu, Pb, and Zn regarding their content, correlation (Pearson coefficient), pollution degree, and potential ecological risks was conducted. Results The heavy metal contents in the sediments decreased in the order of Zn > Cu > Cr > Pb > As > Cd, with contents of 175.79 mg kg−1, 50.75 mg kg−1, 40.62 mg kg−1, 37.10 mg kg−1, 18.27 mg kg−1, and 0.20 mg kg−1, respectively. The results showed that the overall sediment quality in Shenzhen Bay generally met the China Marine Sediment Quality criteria, and the heavy metal contents were significantly lower than those reported in the same type of bay area worldwide. Furthermore, the order of grade of potential ecological risk of the heavy metals was as follows: As and Cd were found to pose moderate ecological risks, with their potential hazard indices reaching a high level, whereas the potential ecological hazard indices of Cu, Pb, Zn, and Cr were all at relatively low levels. Conclusions The potential hazard indices of the heavy metals decreased from the inner bay toward the outside. The accumulation and content of the analysed heavy metals in the Shenzhen Bay sediments are mainly controlled by historical land-source pollution and land reclamation projects. This study presents the current state of sediment quality in Shenzhen Bay. The results may assist in the definition of future bay area management measures specifically targeted at monitoring heavy metal contamination.

DETERMINATION OF NATURAL RADIONUCLIDE AND ASSESSMENTS OF HEALTH HAZARDS IN CHICKEN FEEDS AND MEAT CONSUMED IN LAGOS, NIGERIA

Poultry farming is a highly profitable and not capital intensive agricultural project. It is becoming one of the highest investments in agriculture in Nigeria. The proliferation of self -produced feeds by the Farmers with the addition of some minerals to stimulate growth could elevate the levels of radionuclides in feeds. This, therefore, calls for the determination of the health effects from the consumption of these chicken meats and organs. 10 samples of broilers and 30 feed samples (10 each of Starter, Grower, and Finisher feeds used in feeding the chicken) were used; collected from five selected poultry- farms in Lagos State, Nigeria, and analyzed using spectrometry analysis with NaI (Tl). The results obtained showed that concentrations of 40K, 232Th, and 226Ra were 49.0±25.8, 24.9 ±12.2, and 32.9 ±16.2 Bqkg-1 respectively, in chicken meats. In the feeds, their values were below the UNSCEAR recommendation. The annual effective doses in chicken meats and organs were lower than the 70µSv/yr limit. The cancer risk was within the recommended limit, and the internal hazard indices were below unity. The mean values of the transfer coefficient (TC) were also below 1 for 40K, higher than unity for 226Ra in Finisher feeds, and 232Th in Starter feeds. The starter and finisher feeds were moderately contaminated. So, feeding chicken with these feeds may expose the consumers to the danger of over-exposure to 226Ra and 232Th.