Analytical strategies for determining the sources and ecotoxicological risk of PAHs in river sediment

In this work, analytical strategies were applied aiming at determining sources and ecological risk of PAHs in river sediments. A total of 23 PAHs (16 EPA + 7 alkylated derivatives) were determined in sediment samples. The concentration of total PAH (∑23PAH) span from 0.260 to 2.10 μg g− 1 dw. The molecular ratios indicated a prevalence of pyrolytic pollution sources due to wood combustion processes and refined oil products. The ecological risk was assessed by considering the Sediment Quality Guidelines (SQGs). It was noted that all of the individual PAH concentrations are below the ERM (average variation effect). The ∑23PAH was also below the total of ERL (low variation effect) from 4.02 μg g− 1 dw. The synergy between individual PAHs was assessed using the indices of quality (mSQGq). Accordingly, the risk associated with the simultaneous contamination of the total PAH varied from low to moderate for the different sediments samples of river. The river is located in the state of Bahia, in a region that concentrates the first and largest integrated industrial complex of Brazil.