Oil exploitation, the basis of the world energy sector, is linked to risks and accidents, causing damage to the affected regions. Oil-suspended particulate matter aggregate (OSA) is a promising technology to mitigate those effects. The present study periodically (February 2016 and July 2016) evaluated the dispersion of oil at 28 points in the São Paulo River's estuary, Todos os Santos Bay, Brazil, analyzing the influence of suspended particulate matter (SPM), particulate organic carbon (POC), ions, and chlorophyll on the formation OSA, targeting the prediction of possible ecotoxicological risks. The results showed that the estuary presented similar characteristics in the expeditions, reflecting the oil dispersion pattern through the formation of OSAs, being 92.86% dispersed in the column in the first and 85.71% in the second expedition. The results also pointed to the possibility of pollution in the food chain, reduced fertility, the emergence of abnormalities and the gradual disappearance of species across the whole river in a possible oil spill.
Keywords: Coastal environments; Ecotoxicology; Estuary; Oil; Oil-suspended particulate matter aggregate—OSA.