_____________________________________________________________________________________________________ *Corresponding author: E-mail: nkwilly@gmail.com, kpobari_nkpaa@uniport.edu.ng; Annual Research & Review in Biology 31(1): 1-10, 2019; Article no.ARRB.35339 ISSN: 2347-565X, NLM ID: 101632869 Distribution, Characterization and Health Risk Assessment of Manganese in Vegetables and Root Tubers from Gokana, Rivers State, Nigeria K. W. Nkpaa 1* , B. A. Amadi 1 and M. O. Wegwu 1 1 Environmental Toxicology Unit, Department of Biochemistry, Faculty of Science, University of Port Harcourt, P.M.B 5323, Choba, Rivers State, Nigeria. Authors’ contributions This work was carried out in collaboration among all authors. Authors KWN and MOW designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors KWN and BAA managed the analyses of the study. Author KWN managed the literature searches. All authors read and approved the final manuscript. Article Information DOI: 10.9734/ARRB/2019/v31i130038 Editor(s): (1) Dr. Innocent Dossou-Aminon, Faculty of Sciences and Technology of Dassa (FAST Dassa), Polytechnic University of Abomey-Calavi, Benin. (2) Dr. George Perry, Dean and Professor of Biology, University of Texas at San Antonio, USA. Reviewers: (1) Yukui Rui, College of Resources and Environmental Sciences, China Agricultural University, China. (2) Dr. Abida Begum, PESIT-BSC, India. (3) Mustafa Turkmen, Giresun University, Turkey. Complete Peer review History: http://www.sdiarticle3.com/review-history/35339 Received 11 May 2017 Accepted 31 July 2017 Published 25 March 2019 ABSTRACT Food safety and toxic metals accumulation in agricultural soil and food crops grown on such soils are major concern globally as a result of their significant health risks. This study was designed to evaluate the Manganese (Mn) level in vegetables, root tubers and agricultural soils in six communities in Gokana, Rivers State, Nigeria. Mn transfer from soil-to-plant, average daily intake, and human health risk were also calculated. The level of Mn in vegetables and root tubers ranged between 2.19±0.23 – 28.4±1.27 mg/kg and 8.11±0.99 – 56.4±2.12 mg/kg, respectively. While Mn in vegetables and root tubers associated soils ranged between 27.1±1.18 - 88.4±1.77 mg/kg and 33.4±1.84 - 92.3±1.39 mg/kg, respectively across the various study sites. The higher bio- concentration factor (BCF) was obtained for cassava from B-Dere, Gbe and Bodo City. About 55.2% of THQ calculated were > 1. In this study, the daily intake of Mn via the consumption of vegetables and root tubers are more likely to pose severe health risks to the exposed population in Gokana and children are more susceptible to Mn toxicity than adults. Original Research Article