en Medical Physics Medical Physics تحقيق بديع Original Research <div style="text-align: justify;">Background: River Niger is the principal river of Western African and is Africa&rsquo;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.&nbsp; 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 ⁴⁰K (231&plusmn; 21 Bq kg^-1), ²³²Th (10&plusmn;1 Bq kg^-1), ²²⁶Ra (75&plusmn;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.</div> Contamination factor, heavy metals, pollution load index, radionuclides, sediment, quantification of contamination. 309 316 http://ijrr.com/browse.php?a_code=A-10-2055-115&slc_lang=en&sid=1 E.B. Faweya Faweya.ebenezer@lmu.edu.ng 7900319475328460020088 7900319475328460020088 Yes Radiation and Health Physics Division, Department of Physics, Ekiti State University, Nigeria T. Adewumi 7900319475328460020089 7900319475328460020089 No Department of Physics, Faculty of Science, Federal University of Lafia, Nasarawa State Nigeria