Implications for Instrumental Neutron Activation Analysis (INAA) to Study Bhairab River Sediments using Research Reactor Based Gamma Spectrometry

Abstract

Pollutions are increasingly becoming great concerns for human beings. The present study investigates the distribution and contamination of trace elements in the sediment samples of the Bhairab River, passing through the Khulna city, Bangladesh. Instrumental Neutron Activation Analysis (INAA) method has been used for analyzing the sediment samples collected from Bhairab River during September-october’2016. Quality control of the analysis has also been performed by analyzing certified reference materials IAEA-Soil-7. The irradiation of the samples and standards have been performed using 3 MW TRIGA Mark-II Research Reactor and the gamma-ray spectrometry has been performed by High Purity Germanium (HPGe) detector system. Total element of 28 like Na, Mg, Al, K, Ca, Sc, Cr, Mn, Fe, Co, Zn, Ga, As, Br, Sb, Cs, Ba, Ce, Nd, Eu, Tb, Dy, Ho, Tm, Yb, Lu, Ta, and W has been determined from ten sediment samples collected from different areas of the Bhairab River. In this experiment, NIST-1633b (coal fly ash) has been used as the standard and the analytical accuracy and precisions have been ensured by the repeated (n = 4) analysis of IAEA-Soil-7. Both geochemical and anthropogenic origins of heavy metals (HMs) are considered during the evaluation of compositional trends by the environmental indices such as contamination factor (CF), pollution load index (PLI), geo-accumulation index (Igeo) and enrichment factors (EF). Experimental evidence as pollution level of pollutants evaluated by different pollution indices suggests that Bhairab river sediments are less contaminated. The calculated pollution load index values also suggest the corrosion of the sediment quality and to be helpful to set a picture of metal contamination of the Bhairab River and will be able to find out the elemental abundances of the sediments.