Trace metal levels in various Oryza sativa brands sold in Nigeria

Abstract

Levels of selected trace metals namely Cadmium, Lead, Nickel and Iron in local and imported brands of rice popularly consumed in Nigeria were investigated to ascertain their toxicity levels in the brands. Lead and Nickel were found to be well above safety levels of 1.5mg/kg and 0.2mg/kg respectively as specified by world health organization (WHO) while all the brands were safe from cadmium and iron toxicity. The results obtained for cadmium were comparable with the findings of other researchers, while our results for Lead, Nickel and Iron were higher than results obtained by other researchers. The local brands’ mean concentration for lead showed 9.5toxicity above safety levels while imported brand showed 4.6 toxicity above safety levels. In the local and foreign rice brand, nickel was found to be 31.2 and 85.8 respectively more toxic relative to accepted safety levels. Regular consumers of rice (local and imported) must be cautious to avoid health challenges associated with Lead and Nickel toxicity. Conversely rice (local and imported) brands need to be fortified with other related food supplement to balance their cadmium and iron deficiency.Keywords: Trace Metals, Toxicity, Rice Brands, Chronic Disease