Our study is part of an environmental analytical chemistry approach aimed at characterising soil contamination by heavy metals resulting from informal management activities of electrical and electronic equipment waste. Soil samples were collected from collection, dismantling, recycling, and control zones. After drying, sieving, and acid mineralization (HNO3/HCl), pseudo-total concentrations of Pb, Cd, Cu, Zn, Fe, Mn, Cr, and Co were quantified by atomic absorption spectrometry (AAS). In parallel, pH and electrical conductivity were also measured. Principal component analysis (PCA) reduced the dimensionality of the dataset, highlighted the correlations among variables, and identified the sources of contamination. The results of the PCA show a clear differentiation between anthropogenic metals (Pb, Cd, Cu, Zn), which are strongly associated with informal recycling activities, and elements related to the natural geochemical background (Fe, Mn). The integration of analytical chemistry thus allows not only for the quantification of pollution but also for the interpretation of its dynamics and sources, constituting an essential lever for risk assessment and environmental decision-making.
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