Elemental Composition Analysis of Soil Samples from Bayelsa State in the Niger Delta Region of Nigeria

This study analysis the elemental composition and concentration of elements in the soils of the study area to ascertain degree of elemental enhancement in the soil resulting from anthropogenic activities with possible soil contamination, human health and environmental detriment. The study area was divided into eight grids and two soil samples per grid from over burden to a depth of 900mm was collected randomly in each grid. The samples were prepared using standard methods and analyzed with a linear accelerator. The number of detectable elements and their quantitative information was extracted from the elemental spectral signatures. . The result showed a high concentration value in some elements in the soil samples above values of elemental concentrations in soils from other reported studied region. In addition, Aluminium, Strontium, Barium, Gallium etc also showed an extremely high value in their concentration that exceeds the world wide mean range upper limit values in crustal soil study published. The study indicates some degree of potential contamination and therefore necessitate a regular periodic monitoring study to reduce potential health detriment to humans and the environment to as low as reasonably possible

Spatial Distribution of Radiometric and Dosimetric Parameters in Soil Samples from Selected Areas in Bayelsa State, Nigeria

Radiation from radioactive materials/radionuclides in the environment enhanced by anthropogenic activities is presently of a great concern globally. The objective of this study is to determine the radiometric and dosimetric parameters from soil samples collected randomly from the study area of Bayelsa State, Nigeria. The samples were prepared using standard methods and analyzed with a high resolution Hyperpure Germanium Detector configuration (HPGe). The results showed the clay samples to have higher activity concentration to the sands samples with activity concentration of clay samples ranging between 68.99±9.05 –189, 42±21.11Bq/kg and the sand samples with activity concentration range of 17.95±5.87 – 38.59±7.43Bq/kg. The activity concentration spatial distribution map in clay lithologies showed 2 peak values trending north-west, while the sand lithology showed a single peak central distribution. The result also showed the values of the absorbed doses with the 8 clay samples values ranging between 59.09 - 155.25nGy/h and sand samples values between 17.90 – 33.92nGy/h. The spatial distribution of the dose showed 2 peak central distribution in clay samples and north-east trending distribution of high peak values for samples with sand lithologies.  In addition, the results showed an effective absorbed dose of range of 0.235-0.0616mSv/y for samples with clay lithology and 0.0071-0.0135mSv/y for samples with sand lithology The activity concentration of all the samples studied are below the 1000Bq/kg international reference limit  for Radium 226, Thorium 232, uranium 238 and 10,000Bq/kg for potassium 40. The absorbed dose rate and annual effective absorbed dose are also below the international reference limits published by ICRP, 2007 and UNSCEAR, 2000 publications. Also, effective activity maximum limit of 370Bq/kg for input raw materials for public building is not exceeded