Polychlorinated Biphenyls Contamination in the Waters from the Déganobo Lacustrine System: Ecological and Public Health Implications

Abstract

Polychlorinated biphenyls (PCBs) are persistent organic pollutants of major concern due to their long environmental half‑life and high ecotoxicological potential. In Côte d’Ivoire, data on PCB contamination of surface waters remain scarce, necessitating targeted investigations. This study assessed PCB contamination in the Déganobo lacustrine system and the associated ecotoxicological risks. A total of 96 water samples were collected monthly between August 2021 and July 2022. Seven indicator PCBs (28, 52, 101, 118, 138, 153, 180) were quantified following NF ISO 6468. The ecotoxicological risks were evaluated using SEQ‑Eau V2, Hazard Index (HI), and Risk Index (RI). PCB 52 consistently showed the lowest concentrations, whereas PCBs 118 and 138 were predominant across seasons. SEQ‑Eau V2 classified the waters as unsuitable for biological productivity and anthropogenic use. HI values remained below 1, and RI values below 10⁻⁶, indicating negligible carcinogenic risk to humans. Overall, findings reveal significant ecological impairment of the Déganobo waters due to PCB contamination, while human carcinogenic risks appear minimal under current exposure conditions.