Evaluation of Heavy Metal Concentrations and Pesticide Residues of Honey Harvested by Beekeepers from Selected Towns in South East Nigeria

Abstract

This study evaluated heavy metal concentrations and pesticide residues of honey harvested by beekeepers from selected towns in South east Nigeria. Four samples of natural honey harvested by beekeepers in Onitsha, Amizi, Enugu and Awka were used for this study. The Atomic Absorption Spectrophotometer and High Performance Liquid Chromatography were used to determine the levels of heavy metals and pesticide residues respectively.  The results showed that Cadmium levels were lowest in Enugu (0.157 mg/kg) and highest in Awka (3.124 mg/kg). The concentration of Zinc was highest in Awka (4.327 mg/kg) and lowest in Enugu (0.151 mg/kg). Iron was not detected in the locations except in Awka (0.065 mg/kg). Awka also recorded the highest concentration of nickel (0.266 mg/kg) while Onitsha had the least (0.014 mg/kg). Chromium level was highest in Onitsha (0.019 mg/kg) while the least in Enugu (0.015 mg/kg). No significant difference was found in all heavy metal concentrations among the four locations, except in zinc and cadmium. Although cadmium and nickel exceeded the permissible limits, zinc, iron, and chromium did not. Significant differences were found in pesticide residue concentrations of honey samples among locations. However, with the exception of 2_4 DDT, aldrin, diazinon, dicophol, g-chlordane, and heptachlor, all concentrations were below the FAO-recommended limit. The areas with the highest densities were Amizi, Onitsha, and Awka. Tand to raise public awareness about the risks associated with high concentrations of contaminants in honey was highlighted.