Assessment of levels of heavy metals in some common local spices sold in two markets in Cape Coast Ghana

Abstract

The study examined levels of lead (Pb), cadmium (Cd) and copper (Cu) in ten spices sold in Abura and Kotokoraba markets, Cape Coast-Ghana to determine their safety for consumption.  Samples of spices were collected from the markets and analyzed for Pb, Cd and Cu using atomic absorption spectrophotometry. A one-way analysis of variance was used to compare mean levels of metals in spices from these markets, followed by Tukey’s post hoc test to identify specific pairwise differences among the spices. Mean Cd levels were below detectable limits. Mean Pb levels did not differ significantly between markets (F = 1.004, p = 0.450), indicating similar contamination patterns. Mean Cu levels differed significantly (F = 3.472, p = 0.002), with ginger showing markedly higher Cu levels than garlic, rosemary, aniseed, grains of paradise, negro pepper, bay leaf, cloves, and chili pepper. Results suggest that differences found in Cu levels may depend on the type of spice rather than location of market. While Pb contamination appears uniform across both markets, the Cu disparity underscores the need for commodity-specific control strategies. The study recommends targeted monitoring of high risk spices particularly ginger through source tracing, vendor education, and stricter regulatory checks. This research provides a comparative market analysis of heavy metals in Ghanaian spices, offering evidence to strengthen public health protection and ensure safer spice trade practices.