Distribution of Per- and Polyfluorinated Alkyl Substances (PFAS) in Galveston Bay, TX

Yina Liu1, Garrett X Walsh2, Li-Jung Kuo3, Ashley Pavia4, Tracy Fulton5, Stephen T Sweet6, Terry Wade5, Anthony Knap7 and Shari Ann Yvon-Lewis6, (1)Texas A&M University College Station, Geochemical and Environmental Research Group (GERG), College Station, TX, United States, (2)Texas A&M University College Station, Oceanography, College Station, TX, United States, (3)Pacific Northwest National Laboratory, Marine Sciences Laboratory, Richland, WA, United States, (4)Marymount Manhattan College, Department of Natural Sciences, New York, NY, United States, (5)Texas A&M University College Station, Geochemical and Environmental Research Group, College Station, TX, United States, (6)Texas A&M University, College Station, TX, United States, (7)Texas A&M University, Geochemical and Environmental Research Group, College Station, United States
Abstract:
The presence of per- and polyfluorinated alkyl substances (PFAS) in surface waters has received increasing attention from the national and international scientific community and policy makers. Galveston Bay, TX is an urbanized estuary, surrounded by many industries and various Superfund sites, as well as receiving river (San Jacinto and Trinity) effluents from highly populated industrialized areas. Extensive research on contaminant levels in Galveston Bay has existed for decades. Surprisingly, however, little information on concentrations and distributions of PFAS is available. We examined the spatial distribution and temporal variability of PFAS in Galveston Bay seawater. Samples from eight stations along a salinity gradient were collected from September 2017 to June 2019, on a quarterly basis. This time series captures the dynamics and concentrations of PFAS across different seasons with different hydrographical conditions, as well as after extreme events such as Hurricane Harvey and the Deer Park Intercontinental Terminals Company (ITC) fire. In general, elevated total dissolved PFAS (C4 to C8) were observed in the upper bay, near the San Jacinto and Trinity rivers. Significantly elevated perfluorooctanesulfonic acid (PFOS) and 6:2 fluorinated telomer sulfonates (6:2 FTS), compared to background concentrations, were also observed after the ITC fire. This study highlights the importance of time series observations on understanding the distribution and fate of emerging contaminants such as PFAS. Concentration variabilities due to hydrographic changes provide a critical baseline for understanding how extreme events affect the health of an urbanized estuary, such as Galveston Bay, TX.