Bayesian source apportionment and eco-probabilistic risk assessment of aliphatic and polycyclic aromatic hydrocarbons in sediments from the offshore area between the Deep Water Tano and West Cape three points blocks, Ghana

This study investigates aliphatic and polycyclic aromatic hydrocarbons in sediments from offshore Ghana, focusing on their distribution, sources, and ecological risk. Samples were collected from 15 sites near Deep Water Tano and West Cape Three Points blocks. GC-FID and GC–MS analyses revealed higher concentrations in West Cape Three Points compared to Deep Water Tano. Bayesian source apportionment indicated microorganisms as the primary contributor to AHs in both areas. For polycyclic aromatic hydrocarbons, pyrogenic sources dominated in Deep Water Tano (63.3 %), while grass/coal/wood combustion was primary in West Cape Three Points (60 %). Probabilistic risk assessment identified benzo[a]pyrene as posing the highest ecological risk. This study demonstrates the utility of Bayesian methods in identifying hydrocarbon sources and highlights the importance of species-specific sensitivities in ecological risk assessments, providing valuable insights for marine environment management. •Bayesian analysis: micro-organisms primary contributor to AH profile in DTW and CTP.•Combined plankton and petroleum sources show high probability in both regions.•PAH diagnostics reveal combustion sources, particularly biomass, in DTW and CTP.•Spatial distribution of PAHs uneven; CTP higher mean concentrations than DTW.•Probabilistic risk assessment: benzo[a]pyrene poses highest ecological risk among PAHs.