Trace and Heavy Metals in Locally and Imported Spices Sold on Markets in Accra Metropolis, Ghana

Abstract

Spices enhance food’s colour, aroma and palatability. The main objective of this study was to assess the levels of heavy metals in the most common spices used in Ghanaian and worldwide cuisines. Ninety samples were obtained directly from local marketplaces in the Accra Metropolis (Madina, Kaneshie and Makola). After microwave digestion, the samples’ levels of arsenic, iron, lead, cadmium and zinc were measured using an inductively coupled plasma-mass spectrometer (ICP-MS). Iron, zinc, arsenic, cadmium and lead levels in specified natural spices varied from 0.022 mg/kg to 5.814 mg/kg, 0.056 mg/kg to 0.895 mg/kg, not detected to 14.012 mg/kg, 0.02 mg/kg to 0.45 mg/kg and not detected to 3.583 mg/kg, respectively. The toxic metals arsenic and lead in turmeric powder, whole rosemary and garlic, as well as lead in ginger, were slightly above the Codex, but below the FAO/WHO permissible level. All spices in this study had THQ and HI values of less than one, indicating that consumers will experience no potential health hazards from consuming specific metals through spices. However, continual scrutiny should be maintained over time due to bioaccumulation in humans.