Polycyclic Aromatic Hydrocarbon Exposure, Hepatic Accumulation, and Associated Health Impacts in Gulf of Mexico Tilefish (Lopholatilus chamaeleonticeps)

• Main Author: Snyder, Susan M.
• Format: Doctoral or Postdoctoral Thesis
• Language: unknown
• Published: Digital Commons @ University of South Florida 2020
• Subjects: Deepwater Horizon; baseline; condition factor; lipid; Marine pollution; histology; Other Oceanography and Atmospheric Sciences and Meteorology; Northwest Atlantic
• Online Access: https://digitalcommons.usf.edu/etd/8998; https://digitalcommons.usf.edu/context/etd/article/10195/viewcontent/Snyder_usf_0206D_16074.pdf

Following the 2010 Deepwater Horizon oil spill, systematic demersal longline surveys were conducted throughout the Gulf of Mexico (GoM) continental shelf to evaluate polycyclic aromatic hydrocarbon (PAH) exposure, hepatic accumulation, and health indices in demersal fishes. Tilefish (Lopholatilus chamaeleonticeps) were chosen as a target species due to high vulnerability to environmental disturbance, commercial importance, Gulf-wide distribution, and documented high exposure to PAHs post-Deepwater Horizon. Over 200 Tilefish were sampled in the north central GoM at repeat stations from 2012 to 2017, and from the northwest GoM, southwest GoM, Bay of Campeche, and Yucatán Shelf over years 2015 and 2016. Tilefish were sampled for biometrics, and bile and liver for contaminant analyses. Tilefish livers were also obtained from demersal longline surveys in the northwest Atlantic Ocean for comparison. Bile samples were analyzed via high performance liquid chromatography with fluorescence (HPLC-F) detection for PAH metabolites, a biomarker of short-term (e.g. days) exposure to PAHs. Longer-term accumulation of PAHs was assessed by analyzing liver samples for PAHs and alkylated homologs using the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method and gas chromatography tandem mass spectrometry (GC-MS/MS). Fish health indices including Fulton’s condition factor and total liver lipid were evaluated. Liver samples were also analyzed for microscopic hepatic changes (MHCs) by a board-certified veterinary pathologist. Over the six-year time series in the north central GoM, exposure to petrogenic PAHs increased by an average of 178%, correlating with an average 22% decline in Fulton’s condition factor. The decline in Fulton’s condition factor was positively correlated with a 53% decline in percent liver lipid. There was no accumulation of PAHs in liver tissue over time. Together, these results suggest that increasing and chronic PAH exposure and resultant elevated xenobiotic metabolism may be taxing the ...