Contamination and Pollution Risk Assessment of Heavy Metals in Rice Samples (Oryza sativa) from Nasarawa West, Nigeria

Abstract

Aim: This study was undertaken to assess the heavy metals contamination level in rice grains (Oryza sativa) from Nasarawa West, Nigeria. Study Design: To estimate the contamination factor, degree of Contamination and Pollution load index of rice samples from Nasarawa west using the world health organization/food and agricultural organization acceptable limits of some toxic Heavy Metals in Food as reference heavy metals concentration. Place and Duration of Study: The research was carried out in the Department of physics, Nasarawa State University, Keffi, from September 2017 to April 2018. Methodology: Fifteen (15) samples each were taken from various locations from the rice fields in Keffi, Kokona, Karu, Nasarawa, and Toto respectively. Rice grain samples were dried in an open air at an ambient temperature to constant weight. Husks were removed. Then, the grain rice samples were pulverized and were passed through a 2.00 mm sieve and stored in closed polyethylene bags for irradiation using ECLIPSE Ш Energy Dispersive X – Ray Fluorescence (EDXRF) XR–100 CR spectrometer supplied by AMTEK INC. MA; USA. Results: The values of contamination factor of rice samples from the study area were in the order of Zn < Cu < Ni < Cr < Pb and are all less than 1, indicating a ‘low risk’ of contamination with the value of Cd >> 6 presenting a very high contamination risk of Cadmium. The Pollution Load Index value observed in Nasarawa West were in the order of Nasarawa (0.0683) < Keffi (0.0773) < Toto (0.0972) < Kokona (0.0988) < Karu (0.1389) and are all less than unity (1), indicating that the rice samples were not polluted by Cd, Cu, Cr, Ni, Pb and Zn. Conclusion: Findings from this study will help in making policies and preferring solution to public health related issues and further studies may be important.