EVALUATING THE WEATHERING AND TRANSPORT OF PLASTIC NURDLES ALONG THE NORTH- AND SOUTHWESTERN GULF OF MEXICO COASTS

Plastic nurdles, as small resin pellets, are a significant pollutant across the north- and southwestern Gulf of Mexico coasts from Texas to Yucatan Peninsula. In this study we conducted chemical analysis and physical oceanographic modelling to identify the sources, weathering, and movement pathways of nurdles on shorelines. Preliminary chemical data collected from over 70 sites from Houston to the Yucatán Peninsula (2021–2024) reveal distinct patterns in color, polymer type, and weathering status, which help to identify nurdle origins and their environmental exposure times. Polymer analysis through Fourier Transform Infrared Spectroscopy (FTIR) shows polyethylene (PE) as the dominant polymer across all the regions sampled, while color categorization reveals fresher white nurdles clustering around Texas sites and more weathered yellow nurdles in Mexico, suggesting that nurdles may have been mainly sourced from Texas and been continuously weathered during the transit to Mexico coasts. Weathering indices, including oxidation markers, further support these findings, showing increased degradation in nurdles collected farther from Texas. Physical oceanography modelling, including wave and current patterns, will be developed for nurdle movement, which will further refine our understanding of nurdle mobility throughout the Gulf and confirm or challenge our hypothesis that Texas is the primary source of this plastic pollution. This research not only highlights the regional differences in nurdle distribution but also offers crucial insights into the movement patterns of other types of microplastics in the Gulf of Mexico.

Presentation Preference: Poster

Primary Presenter: Jordan Cisco, Ut Austin (graduate student) (j.cisco@utexas.edu)

Authors:

Jordan Cisco, University of Texas at Austin  (j.cisco@utexas.edu)

Jiabi Du, Texas A and M  (jdu@tamug.edu)

Xiangtao Jiang, University of Texas at Austin  (xtao.jiang@utexas.edu)

Jace Tunnell, Texas A and M Corpus Christi  (jace.tunnell@tamucc.edu)

Zhanfei Liu, University of Texas at Austin  (zhanfei.liu@austin.utexas.edu)