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

Mar Pollut Bull. 2020 Nov:160:111542. doi: 10.1016/j.marpolbul.2020.111542. Epub 2020 Oct 5.

Abstract

The anthropogenic impact in the Wouri Estuary Mangrove located in the rapidly developing urban area of Douala, 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, 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 far water resources are shifting within what is now termed the Anthropocene due to increasing local pressures in developing countries or African countries.

Keywords: Africa; Mangrove; Pesticides; Polychlorinated biphenyls; Polycyclic aromatic hydrocarbons; Sediments.

MeSH terms

  • Cameroon
  • Environmental Monitoring
  • Environmental Pollutants*
  • Estuaries
  • Geologic Sediments
  • Hydrocarbons, Chlorinated* / analysis
  • Pesticides* / analysis
  • Polychlorinated Biphenyls* / analysis
  • Polycyclic Aromatic Hydrocarbons* / analysis
  • Water Pollutants, Chemical* / analysis

Substances

  • Environmental Pollutants
  • Hydrocarbons, Chlorinated
  • Pesticides
  • Polycyclic Aromatic Hydrocarbons
  • Water Pollutants, Chemical
  • Polychlorinated Biphenyls