Evaluation five years after a Refinary Oil Spill in freshwater wetland - Paraná State, Southern of Brazil

Abstract

In order to evaluate the Getulio Vargas refinery oil spill - 2000, Parana State - Brazil the presence of PAHs in the sediment, PAHs bioavailability through bile chemical analysis and biochemical and morphological biomarkers were investigated in a native fish species Hyphessobrycon reticulates. The histophatological parameters were also considered to another native species Phalloceros caudimaculatus. Sediment analysis showed the presence of 5-6 rings PAHs on the surface layer and 2-3 rings PAHs in the deepest sediment showing that oil is still accumulated in sediment, and its bioavailability is confirmed by the accumulation of PAHs in bile. Lipid peroxidation, catalase (CAT), GST and cholinesterase activities indicated respectively oxidative stress in liver of H. reticulatus and neurotoxicity, also evidenced by genotoxic and histopathological damages. Despite of the occurrence of other pollutants not identified in the current study, the data presented here may suggest that 5 years after the accident animals as fish can be still affected by hydrocarbons and PAHs presented in the sediment. Concluding, studies must be done to confirm that with a more sophisticated chemical analysis, but this work is the only study realized after the accident. We strongly suggest a new study to compare and verify if still there is risk to biota.