Quantification of Some Metals in Commonly Consumed Canned Foods in South-west Nigeria: Probable Pointer to Metal Toxicity

Abstract

Canned foods are one of the most commonly consumed products, due to benefits like the taste, handiness and convenience derived from them. On the other hand, these dietary products may be a means of heavy metal exposure and toxicant. This study aimed to quantify metals content in some frequently consumed canned foods in Nigeria as a possible source of toxicity. Twenty-two different commonly consumed brands of canned foods (Sweet corn, Green peas, Corned beef, Hotdog, Mushroom, Tin tomato, Mixed fruit, Baked beans, Mackerel (tomato sauce canned fish), Sardine (canned fish in vegetable oil) and Red kidney were analyzed for Ni, Cr, Cu, Pb and Al using Atomic Absorption Spectrophotometer after wet digestion. The results showed that the heavy metals concentration in the samples under study ranged from 0.55 to 0.86mg/kg (Ni), 0.00 to 0.41mg/kg (Cr), 1.40 to 1.76 mg/kg (Pb), 0.07 to 0.2mg/kg (Cu) and 4.71 to 16.4mg/kg (Al). The levels of Pb, Ni and Al were above FAO/WHO recommended limit of 0.01mg/kg, 0.05mg/kg and 7mg/kg respectively. The presence of heavy metals like lead (Pb) above the permissible limit calls for caution during production and in the frequent consumption of canned foods which may lead to accumulation of metals, toxicity and the sequelae.