Graduation Year

2020

Document Type

Thesis

Degree

M.S.

Degree Name

Master of Science (M.S.)

Degree Granting Department

Marine Science

Major Professor

Steven A. Murawski, Ph.D.

Committee Member

Erin L. Pulster, Ph.D.

Committee Member

Jorge Angulo-Valdes, Ph.D.

Keywords

Baseline, Fish, Marine Pollution, OCP, PAH, PCB

Abstract

The Snapper species assemblage is economically and environmentally important to all three countries bordering the Gulf of Mexico (GoM). Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were investigated in seven snapper species located in the GoM, with a specific focus on the those caught along the northwestern coast of Cuba. Hepatic samples were processed using QuEChERs extraction methodology and analyzed using gas chromatography with tandem mass spectrometry (GC-MS/MS). Nearly all fish included in this study contained detectable amounts of all three groups of these contaminants, regardless of location, and across all regions of the Gulf, indicating that PCB, OCP, and PAH contamination in fisheries is ubiquitous in the Gulf of Mexico. Measured values of these three groups of persistent organic pollutants (POPs) were within the same order of magnitude as other species in the GoM and globally, with concentrations of ΣPCBs ranging from 0.80 to 427 ng g-1 wet weight (w.w.), ΣOCPs from 4.00 to 247 ng g-1 (w.w.), and ΣPAHs from 60.0 to 2,991 ng g-1 (w.w.). Wenchman were found to have increased hepatic PCBs compared to other snapper, and Silk Snapper elevated hepatic PAHs. Species-specific variation in hepatic total load and composition of PAHs, OCPs, and PCBs suggest species-specific differences in xenobiotic metabolism. Contaminants are correlated with several fish biometrics and health indicators, including negative relationships between PCBs and Fulton’s condition factor, and between PAHs and hepatic lipids. These correlations may indicate that snapper with elevated exposure to these contaminants are experiencing a range of sublethal effects. Regional variation observed in hepatic concentrations and compositional profiles were likely driven by local onshore contamination sources, chemical usage patterns, and riverine input. Spatial gradients observed in PCB and DDT concentrations were along the northwest coast of Cuba are likely driven by proximity to the city of Havana. The results of this study demonstrate possible connections between onshore development/industrial activity and impacts to offshore ecosystems. These data also serve to establish critical contaminant baselines for this group of economically important GoM fishes, and will contribute to assessing the impact of any future pollution events or changes in contaminant inputs within the area. This information will also help to fill some of the gaps in our understanding of the presence and possible impacts of these organic contaminants in GoM snapper fisheries.

Included in

Toxicology Commons

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