Persistent organic pollutants in sediments of the Wouri Estuary Mangrove, Cameroon: Levels, patterns and ecotoxicological significance

Kevin Mbusnum (1) , Laure Malleret (1) , Pierre Deschamps (2) , Imen Khabouchi (1) , Laurence Asia (1) , Stéphanie Lebarillier (1) , Guillemette Menot (3) , Raphael Onguene (4) , Pierre Doumenq (1)

1 LCE - Laboratoire Chimie de l'environnement
2 CEREGE - Centre européen de recherche et d'enseignement des géosciences de l'environnement
3 Université de Lyon
4 Université de Douala

The anthropogenic impact in the Wouri Estuary Mangrove located in the rapidly developing urban area of Doula, Cameroon, Africa, was studied. A set of 45 Persistent Organic Pollutant were analysed in surficial mangrove sediments at 21 stations. Chlorinated Pesticides (CLPs), Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs) have concentrations ranging from 2.2-27.4, 1.7-31.6 and 83-544 ng/g, respectively. The most abundant CLPs were endosulfan, alachlor, heptachlor, lindane (γ-HCH) and DDT, which metabolites pattern revealed recent use. Selected PAHs diagnostic ratios show pyrolytic input predominantly. The sum of 7 carcinogenic PAHs (ΣC-PAHs) represented 30 to 50% of Total PAHs (TPAHs). According to effect-based sediment quality guidelines, the studied POPs levels imply low to moderate predictive biological toxicity. This study contributes to depict how fare water resources are shifting within what is now termed the Anthropocene due to increasing local pressures in African developing countries.

Mots clés: Pesticides; Polycyclic Aromatic Hydrocarbons; Polychlorinated Biphenyls; Sediments; Mangrove; Africa

Domaines: Sciences de la Terre

Kevin Mbusnum, Laure Malleret, Pierre Deschamps, Imen Khabouchi, Laurence Asia, et al.. Persistent organic pollutants in sediments of the Wouri Estuary Mangrove, Cameroon: Levels, patterns and ecotoxicological significance. Marine Pollution Bulletin, 2020, 160, pp.111542. ⟨10.1016/j.marpolbul.2020.111542⟩. ⟨hal-03152699⟩