Assessment of Some Heavy Metals Content of Road-Side Vended Food Stuffs in Keffi Metropolis

Abstract

This paper reports moisture, ash and some heavy metals (Cu, Pb, Zn, Cd and Cr) levels in roadside exposed foodstuffs (tiger nuts, date palm fruits, garri and cassava flour) in comparison to their counterparts stored under refrigeration at 15 ^OC. These foods were obtained from Keffi Roadside Market, Nasarawa State – Nigeria. The results of moisture content of the foodstuffs indicate higher values for refrigerated samples than the roadside ones. Ash contents on the other hand show refrigerated samples to be lower than those exposed by the roadside. Heavy metal analysis indicates Cu to be present in exposed samples of tiger nuts and date palm fruits (0.1 mg/kg and 0.2 mg/kg respectively), whereas it was not detected in exposed samples of garri and cassava flour and all refrigerated samples. Lead contents of the exposed and refrigerated samples of tiger nuts were found to be 0.16 mg/kg and 0.09 mg/kg respectively, while that of the date palm fruit was 0.10 mg/kg and 0.09 mg/kg respectively.  Exposed samples of garri and cassava flour were found to contain 0.15 mg/kg and 0.18 mg/kg of lead respectively, while 0.05 mg/kg and 0.20 mg/kg were recorded for the refrigerated respectively. Zinc was found to range between 0.65 mg/kg to 7.11 mg/kg for the exposed and 0.05 mg/kg to 0.23 mg/kg for refrigerated. Cadmium was not detected in both the exposed and refrigerated samples except for the exposed sample of cassava flour (0.01mg/kg). Chromium was detected only in the exposed samples of date palm fruits and garri (0.06 mg/kg and 0.10 mg/kg). The results indicate that food products exposed by the roadside are subject of contamination by automobile emission, although values obtained in this study were below FAO/WHO maximum permissible limit, continuous exposure may lead to bioaccumulation. This suggests that those who constantly depend on such foodstuffs are likely to be deposed to cumulative effect of food poisoning by these heavy metals.