Aliphatic and Polycyclic Aromatic Hydrocarbons and Sulfur/Oxygen Derivatives in Northwestern Mediterranean Sediments: Spatial and Temporal Variability, Fluxes, and Budgets

Abstract

The spatial and temporal distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) and sulfur/oxygen derivatives in sediments from the NW Mediterranean basin were investigated. Along the Continental Shelf and slope, an unresolved complex mixture (UCM) of aliphatic hydrocarbons and alkylated PAHs, indicative of petrogenic inputs, were predominant. Long-chain n-alkanes derived from terrestrial plant waxes (n-C27, n-C29, and n-C31) and parent PAHs, which are typical of high-temperature combustion processes, were evenly distributed in the whole basin and largely prevailing in the deepest areas. Perylene, a geochemically derived PAH, was found highly abundant in the areas influenced by river discharges. The highest anthropogenic hydrocarbon inputs were found near the cities of Marseille and Barcelona, being the contribution of the Rhone River ca. 25 times higher than that of the Ebro. Fluxes of PAHs in the deep basin were consistent with a predominant atmospheric input. These results account for an...