Assessment of heavy metals in foods and adult dietary intake estimates

Abstract

Levels of some heavy metals were investigated in 114 snack samples consumed in Ibadan city, Nigeria. The concentrations of the selected metals were observed to range widely in the sampled food snacks: cadmium (0.004 to 0.892 mg/kg), cobalt (0.090 to 0.797 mg/kg), chromium (0.015 to 0.702 mg/kg), copper (0.077 to 07.548 mg/kg), iron (0.070 to 65.11 mg/kg), nickel (0.165 to 3.327 mg/kg), lead (0.069 to 1.207 mg/kg), and zinc (0.015 to 94.382 mg/kg). Mean concentrations of the selected heavy metals were found to range from 0.179 mg/kg (observed for cadmium) to 21.632 mg/kg (observed for iron) among the snacks, with iron having the highest level observed in bean cake (62.397 ± 20.10 mg/kg). The levels of the selected heavy metals in the foods were comparable with data reported in studies carried out in other countries. The daily dietary intake of the selected metals for the adult population was observed to differ in the income groups, with the highest intakes observed in the low-income group. For example, dietary intakes of cadmium observed to be 0.080 mg/person/day for the low income group, 0.061 mg/person/day for the middle income group, and 0.040 mg/person/day for the high income group were higher than the range (0.01 to 0.02 mg/person/day) specified by the European Commission (1996).