Heavy metal levels in selected green leafy vegetables obtained from Katsina central market, Katsina, North-western Nigeria

摘要

The levels of Lead (Pb), Cadmium (Cd), Iron (Fe), Zinc (Zn) and Copper (Cu) were determined in four different samples of vegetables purchased from Katsina central market using atomic absorption spectrometer. The mean concentrations of metals ranged from 0.071 mg/kg Pb to 0.632 mg/kg Cu. The relative abundance of metals in vegetables followed the sequence Cu (0.483 mg/kg) Zn (0.268 mg/kg) Fe (0.260 mg/kg) Pb (0.095 mg/kg). The levels of Pb and other metals were below the FAO/WHO recommended limits for metals in vegetables. Low concentrations of Pb and absence of Cd in all the samples are indications that these plants contribute less toxic effects of metals. The results showed that, these vegetables are the main sources of essential trace elements. The daily human intakes of metals have also been computed and were observed below recommended values by the FAO/WHO.