Assessment of geo-accumulation index and contamination factors of zinc (Zn) and lead (Pb) in urban soils of Annaba city

This study assesses the geo-accumulation index (Igeo) and contamination factors (Cf) of zinc (Zn) and lead (Pb) in urban soils of Annaba, Algeria. Soil pollution is a significant environmental issue affecting human health and ecosystems, with heavy metals like Pb and Zn being of particular concern due to their toxicity even at low concentrations. The research involved collecting 25 soil samples from various sites in Annaba, characterized by industrial and urban activities. pH measurements indicated alkaline soils, with values ranging from 7.2 to 7.9. Analysis revealed Pb concentrations between 26.93 and 218.30 mg/kg and Zn concentrations from 103.95 to 713.2 mg/kg. The contamination factor (Cf) indicated moderate to severe pollution, particularly for Zn, which was identified as the most contaminating metal. The geo-accumulation index showed that most sampling sites fell into moderate to heavily contaminated categories for Zn. The findings highlight the urgent need for remediation measures to mitigate heavy metal pollution and protect soil quality in Annaba, emphasizing the importance of monitoring and management strategies to address this environmental challenge.