Doctor of Philosophy (PhD)


Environmental Sciences

Document Type



Approximately 4.9 million barrels of crude oil along with natural gas were released into the Gulf of Mexico (GoM) from April to July 2010 (Deepwater Horizon, DWH, spill). Impacts of this magnitude seldom occur in the GoM (Ixtoc I was the last spill close to this magnitude occurring in 1979), and one cannot predict when they will happen. Major constituents of concern found in crude oil are Polycyclic Aromatic Hydrocarbons (PAHs), which often have low volatility that allows for prolonged existence in the environment. PAHs are compounds of concern according to the United States Environmental Protection Agency (USEPA), with one characteristic being that they have the potential to accumulate within adipose tissue. Several PAHs are listed as mutagenic and carcinogenic, making their presence in commercial fishery populations of major environmental concern. Gulf menhaden fishery was chosen for use as an indicator for impact of crude oil exposure in the years following the spill event. Total whole body PAH concentrations along with both benzo[a]pyrene, toxic and mutagenic equivalents (BaP-TEQ and BaP-MEQ respectively), were used to determine overall impact on the species. Proposed standard weight equations and length categories for Gulf menhaden were developed to assess morphological changes in the species. Lipid content was also used as a metric for determining overall health of the Gulf menhaden. Results are outlined in each chapter abstract.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Portier, Ralph J.