Distribution and enrichment of trace metals in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana in the Gulf of Guinea

• Trace metal distribution & enrichment in sediments sampled across 4 regions off Ghanaian continental shelf.
• Increasing enrichment of trace metals towards nearshore areas were observed.
• Significant enrichment (EFs > 5) with As and Cd across all four regions.
• As fell in Igeo class 4 at depth 25 m in region G4, depicting a strong pollution of the sediment with As.
• Principal Component Analysis showed natural & anthropogenic processes controlled the trace metal distribution & enrichment.

We present results of a preliminary geochemical assessment of Cd, Pb, V, As, Ni, Cu, Zn, Mg, Al, K, Ca, and Fe in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana. Samples were taken along 4 regions G1, G2, G3 and G4 at approximately 25 m, 100 m, and 250 m, 500 m and 1000 m depths. Elemental compositions were assessed through the estimation of Al-normalized enrichment factors and geochemical accumulation indices, and the concentrations determined to produce any potential toxic effects to biota. Significant enrichment of the bottom sediments with Cd, Ni and As were observed at some locations with sediments showing signs of heavy pollution with As at region G4. Apart from Ni, V and As which were beyond threshold effects levels at most regions, all other metals were below probable effect levels. Both natural and anthropogenic processes controlled trace metal accumulation and distribution in the Ghanaian coastal environment.