Heavy Metals and PAHs in Mollusks from The Sangomar Marine Protected Area in ‎Senegal: A Baseline Study

  • Authors

    • Issa BA Laboratoire d’Océanographie, des Sciences de l’Environnement et du Climat (LOSEC), ‎Université Assane seck de Ziguinchor (UASZ), Ziguinchor, Sénégal.; BP 523
    • Ousmane Diankha Département Hydrosciences et environnement, UFR Sciences et Technologies, Université Iba ‎ Der Thiam, Thiès, Sénégal
    • Bamol Ali Sow Laboratoire d’Océanographie, des Sciences de l’Environnement et du Climat (LOSEC), ‎Université Assane seck de Ziguinchor (UASZ), Ziguinchor, Sénégal.; BP 523
    https://doi.org/10.14419/zk9a3751

    Received date: August 19, 2025

    Accepted date: October 1, 2025

    Published date: October 20, 2025

  • Health Risk Assessment; Heavy Metals; PAHs; Crassostrea Gasar; Sangomar MPA; Senegal; ‎Senilia Senilis

  • Abstract

    This study provides the first baseline evaluation of heavy metals (Pb, Cd, Hg) and polycyclic ‎aromatic hydrocarbons (PAHs) in the bivalves Senilia senilis and Crassostrea gasar from the ‎Sangomar Marine Protected Area (Senegal), prior to offshore oil exploitation. Sampling was ‎conducted during the dry and rainy seasons of 2023-2024. Plomb and Hg concentrations ‎remained well below international safety limits, whereas Cd frequently exceeded the ‎permissible threshold, reaching 2.36 mg/kg dry weight in S. senilis. PAH contamination, ‎dominated by pyrogenic four-ring compounds (fluoranthene, pyrene), peaked in S. senilis ‎during the rainy season (190 µg/kg). Health risk assessment indicated that target hazard ‎quotients for Cd approached the critical value of 1 in S. senilis, suggesting possible long-term ‎risks to consumers. These results reveal high Cd exposure and seasonal PAH inputs likely ‎linked to runoff, providing essential reference data for environmental monitoring and ‎informing adaptive management strategies in the face of industrial expansion‎.

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    BA, I., Diankha, O., & Sow, B. A. (2025). Heavy Metals and PAHs in Mollusks from The Sangomar Marine Protected Area in ‎Senegal: A Baseline Study. International Journal of Basic and Applied Sciences, 14(6), 444-452. https://doi.org/10.14419/zk9a3751