Assessment of Heavy Metal Contamination (Cd, Pb, Hg) and Typological Characterization of Smoked Fish Commonly Consumed in Abidjan, Ivory Coast
Monney Yapo Urbain
*
Department of Environmental Sciences, Faculty of Governance and Sustainable Development, University of Bondoukou, P.O. Box V 81 Bondoukou, Ivory Coast.
Diaby Vandjiguiba
Faculty of Agriculture, Fisheries Resources, and Agro-Industry, University of San-Pédro, P.O. Box 01 V 1800, Côte d'Ivoire.
Tra Bi Zamblé Fidèle
Department of Environmental Sciences, Faculty of Governance and Sustainable Development, University of Bondoukou, P.O. Box V 81 Bondoukou, Ivory Coast.
Kakou Kouamé René Sylvestre
Food and Nutritional Security Research Team, Doctoral School of Biology, Environment, and Health, Félix Houphouët-Boigny University, Abidjan, Ivory Coast.
Yapo Adou Francis
Faculty of Biosciences, Biology and Health Laboratory, Félix Houphouët-Boigny University, 22 BP 582 Abidjan 22, Côte d'Ivoire.
*Author to whom correspondence should be addressed.
Abstract
This study assesses contamination by cadmium, lead, and mercury (Cd, Pb, and Hg) in smoked sardines, mackerel, and tuna in Abidjan and characterises the typological structure of these concentrations at two smoking sites (Abobo-Doumé and Vridi-Zimbabwe), based on 180 fish analysed before and after smoking using ANOVA-Tukey, principal component analysis (PCA), and Pearson correlation. Smoking significantly increases Cd and Pb levels in most species, whereas Hg levels decrease, likely because of evaporation associated with moisture loss. At Abobo-Doumé, Pb levels remain within the Codex limit (0.3 mg/kg), with tuna reaching only 38% of the threshold. At Vridi-Zimbabwe, however, Pb levels exceed the limit in mackerel (+46%) and reach 80% of the threshold in tuna, indicating a real health risk. The PCA accounts for 82.37% of the total variance, structured by Hg and Cd on axis 1 and Pb on axis 2, with Cd-Pb (r = -0.223) and Cd-Hg (r = -0.452) oppositions and a Pb-Hg association (r = 0.331). Three distinct typological profiles emerge: a group dominated by Hg (sardines and tuna from Vridi-Zimbabwe and sardines from Abobo-Doumé), one by Pb (mackerel from Vridi-Zimbabwe), and one by Cd (mackerel and tuna from Abobo-Doumé). Mackerel, the species most exposed at both sites, is confirmed as the preferred model for future toxicological studies.
Keywords: Cadmium, lead, mercury, smoked fish, trace metals, typological characterisation, principal component analysis, food safety