Hydrocarbons in surface sediments of harbor areas in a tropical region (Ceará state, northeast Brazil)

Abstract

Sediment samples collected in two harbors of a tropical region of Brazil were investigated for the distribution of linear alkylbenzenes (LABs), aliphatic (AHs) and polycyclic aromatic hydrocarbons (PAHs). The levels of hydrocarbons in sediments from Mucuripe and Pecém harbors were lower than those reported in industrialized sites and threshold levels of sediment quality guidelines. Analysis of AHs revealed an input of biogenic compounds and, according to diagnostic ratios, PAHs in both harbors originated from pyrogenic sources, which can be related to harbor activities. The contribution of local and diffuse sources seemed to be less important, but not negligible. Deposition zones in both harbors are associated to sedimentation of particles, biogenic materials and hydrocarbons. The results of this study can assist in characterization and management of dredged material by providing information on the distribution and sources of hydrocarbons along the tropical zones, which is important for the identification of ecological risks associated with these compounds.