Distribution of polymer types in Matagorda Bay & biofilm presence on surface of plastic pollution: A study using attenuated total reflectance-Fourier Transform Infrared Spectroscopy and principal component analysis

Global plastic pollution presents significant environmental and economic challenges, exacerbated by mismanagement and low recycling rates. Studies have shown other pollutants like persistent organic pollutants (POPs) and heavy metals can sorb to plastic debris in aquatic ecosystems, making them more readily dispersed throughout ecosystems. This study (1) quantified the spatial and seasonal distribution of different plastic polymer types along the Matagorda Bay system, and (2) explored the nature of the biofilm form on these plastic debris and any correlation between biofilm type and polymer type throughout different seasons. This comprehensive study, the most extensive of its kind with over 3,000 samples, investigates the distribution of plastic polymers AND biofilm formation in the Matagorda and San Antonio Bays across three seasons in 2022. Attenuated total reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) along with Principal Component Analysis (PCA) was employed to identify polymer types and investigate biofilm formation on the collected samples. Polyethylene and polypropylene were the predominant polymer types observed across all sites and seasons. PCA suggested that biofilm was prevalent across all polymer types and seasons, and it is made mainly of extracellular polymer substances (EPS) that are rich in carbohydrates and proteins. Spectra integration showed a positive linear relationship between carbohydrate and protein biofilm components. This study not only provides a deeper understanding of biofilm roles in pollutant adsorption, but also introduces a novel, nondestructive approach for examining bacterial biofilms, paving the way for improved environmental management strategies.