Application of Pyrolysis-Based Analytical Methods for Environmental Microplastic Detection
Microplastics, as a class of emerging environmental contaminants, pose global concerns due to their potential ecological and human health impacts. Accurate identification and quantification of microplastics in environmental matrices are essential for assessing their environmental fate and ecological risks. Pyrolysis-based analytical methods, which decompose macromolecules into smaller fragments followed by gas chromatographic separation and mass spectrometric detection, offer high sensitivity and accuracy, making them significant for microplastic analysis. Despite these advantages, their application remains nascent, with limited comprehensive understanding of their applicability across diverse environmental media. This review systematically compares three pyrolysis-based techniques—pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), thermogravimetry-differential scanning calorimetry (TGA-DSC), and thermal extraction-desorption gas chromatography-mass spectrometry (TED-GC-MS)—for microplastic detection in various matrices. The effectiveness of each method is evaluated in terms of sensitivity, selectivity, and matrix compatibility. Critical challenges, including lack of standardized protocols, complex sample pretreatment requirements, and limitations in quantifying mixtures, are identified. Future research directions emphasize the need for standardization, optimization of pretreatment for complex matrices, and integration with complementary techniques such as FTIR and Raman spectroscopy to enhance comprehensive microplastic characterization. This review provides a critical framework for selecting appropriate pyrolysis-based methods and highlights areas requiring further methodological development.