Non-lethal biomarkers of oxidative stress in oiled sediment exposed southern flounder (Paralichthys lethostigma): Utility for field-base monitoring exposure and potential recovery

The Deepwater Horizon (DWH) blowout resulted in the deposition of toxic polycyclic aromatic hydrocarbons (PAHs), in the coastal sediments of the Gulf of Mexico (GoM). The immediate effects on an ecosystem from an oil spill are clearly recognizable, however the longer-term chronic effects and recovery after a spill are still not well understood. Current methodologies for biomonitoring wild populations are invasive and mostly lethal. Here, two potential non-lethal biomonitoring tools for assessment of PAH toxicity and induced biological alterations in the field, were identified using laboratory-validated methods. In this study, sub-adult southern flounder (Paralichthys lethostigma), were chronically exposed to DWH surrogate oiled sediments for 35 days; a subset of these exposed flounder were then provided a clean non-exposure period to ascertain the utility of selected biomarkers to monitor recovery post exposure. After chronic exposure, there was an increase in gene expression of cytochrome P450 1A (CYP1A)...