Analysis of Heavy Metals Concentrations in Food Spices from Some Markets in Port Harcourt Meteropolis, Rivers State, Nigeria

摘要

This study analysed the levels of some heavy metals like copper (Cu), cadmium (Cd), chromium(Cr), nickel (Ni) and lead (Pb) present in selected food spices widely used in Port Harcourt, Rivers State, Nigeria. The Atomic Absorption Spectroscopy (AAS) and wet digestion was used for analysis. The results revealed different concentrations of heavy metals in the food spices analysed. The mean and standard deviation of heavy metals across the samples revealed that copper had the highest concentration in tomatoes (15.45±5.09 mg/Kg), curry (10.30±2.03 mg/Kg), garlic (8.65±2.08 mg/Kg), onions (6.50±2.52 mg/Kg) and uda (6.15±3.75 mg/Kg) respectively. Chromium was only detected in curry (2.75±1.00 mg/Kg), pepper (0.65±0.02 mg/Kg) and salt (0.05±0.00 mg/kg). The detected level of nickel was high in tomatoes (6.90±4.89 mg/Kg), curry (4.09±1.90 mg/Kg), salt (6.15±3.70 mg/Kg) and onions (3.09±2.10 mg/Kg). Lead occurred more in uda (3.08±2.87 mg/Kg), tomatoes (3.80±1.28 mg/Kg), curry (2.86±1.34 mg/Kg) and salt (2.60±0.76 mg/Kg) respectively. Cadmium was not detected in any of the food spices, while in chilles spice no heavy metals was detected. The daily intake limit was calculated and compared with minimum risk level (MRL) values. The concentrations of lead in some of the food spices were much larger than those of MRL values. The regular consumption of the spices can lead to accumulation of these toxic heavy metals in human beings.