Excessive-life time cancer risks due to concentration of radionuclides and quantification of contamination of sediments from dredged portion of Niger River Nigeria

Abstract

Background: River Niger is the principal river of Western African and is Africa's third longest river. The dredged project covers 572 km of the lower Niger, extending from Baro in Niger State to Warri Bifurcation in Delta State. Materials and Methods:The current study estimated the activity concentrations of naturally occurring radionuclides and heavy metals concentrations in the sediment samples from Lower Niger River using gamma -ray and Atomic Absorption spectrometric techniques. Results: The weighted activity concentrations of radionuclides 40 K (231± 21 Bq kg -1 ), 232 Th (10±1 Bq kg -1 ), 226 Ra (75±17 Bq kg -1 ), were obtained in the sediment samples. The radium equivalent, absorbed dose rate, hazardous indices and excessive-life time cancer risk were compared with the international recommended limits. Conclusion:The measured heavy metal concentrations, contamination factor, pollution load index and quantification of contamination indicated that sediment samples from the River were moderately contaminated.