Characterization of Microplastics using Fourier Transform Infrared Spectroscopy (FTIR)

Abstract

Fourier transform infrared (FT-IR) is a spectroscopy technique widely used to analyze polymer profiles of particulate at a chemical level. The goal of this study was to assess the polymer composition of microplastics ingested by aquatic organisms from Lake Champlain. Preliminary results suggest fibers are the most prominent particle type in organisms (N = 482). Among these fibers, the most common plastic polymer was polyester [PET] (14.5%), followed by cellulose [20u ave particle size] (11.1%), alpha-cellulose [99.5% pure] (11.0%), and rayon (8.5%). Fragments were the second most prominent particle type (N = 168) and were commonly polyester [PET] (52%), followed by vinal (9%), polypropylene, isotactic (4%), and rayon (4%). Pellets (N = 14) were primarily vinylidene chlorine [200ppm mhdq] (14.2%) and polyethylene, chlorinated 36% chlorine (14.2%), followed by both vinal (7%), and cellulose nitrate (7%). Films (N = 11) were primarily rayon (27%), poly [methylmethacrylate] (27%), followed by poly [1,4-cyclohexanedimethylene terephthalate] (18%), and polypropylene, isotactic (9%). The least common polymer type found were foams (N = 10) comprised of polyethylene, chlorosulfonated (50%), polyethylene, chlorinated 36% chlorine (40%), and alzon [casein] (10%). Overall, polyester [PET] was more abundant as compared to other plastics and derives from synthetic clothing and food and beverage packaging.