Identification of Microfibers in the Environment Using Multiple Lines of Evidence

Microfibers, characterized as small fibers shed from textiles that are less than 5 mm in size, are a prominent contaminant in the environment. Thus, it is important that we have methods to accurately quantify and characterize them, including in water, sediment, wildlife, seafood, and drinking water samples. Unfortunately, their small size and the presence of different dyes on the microfibers themselves cause difficulties in identification via conventional spectroscopic methods of total attenuated resonance-Fourier transform infrared and Raman. To help solve some of these methodological challenges, we developed a new method employing polymer-dye binding chemistry, density tests, unique surface morphological traits, and fluorescent staining to identify microfibers in environmental samples. The identification method introduced here was tested in our laboratory via trials using microfibers shed from new textiles and environmental samples. We found that the method can be successfully applied to identify the different polymer types of microfibers, which can ultimately help source apportion microfiber contamination in the environment.