Advances in microplastics analysis: Challenges and innovations in aquatic biota studies

Abstract

The continuous fragmentation of plastic waste in aquatic environments has led to the widespread occurrence of microplastics (MP) in biota. These particles vary in size, shape, and polymer composition, and can transport organic and inorganic contaminants, increasing ecological and toxicological concerns. Their determination in biota remains challenging due to complex matrices and the lack of standardized methodologies. Tissue digestion is a critical step, commonly performed using alkaline (KOH) or oxidative (H2O2) treatments, while enzymatic digestion offers selective but higher costs. Advances in analytical techniques, such as μFTIR, μRaman, LDIR, and pyrolysis-GC/MS, have improved polymer identification and quantification. Py-GC/MS provides robust mass-based data, and automated spectroscopic imaging enhances reproducibility and throughput. However, detection of nanoplastics (<1 μm) remains difficult, requiring advanced tools like AFM-IR, SRS microscopy, and LC(SEC)-HRMS. Harmonized workflows, certified reference materials, and validated QA/QC criteria are essential to ensure accurate, comparable data for robust risk assessment in biota.