Microplastic Detectability Investigation in Soils Using X‐Ray Microtomography

ABSTRACT X‐ray microtomography (microCT) is a promising tool for investigating microplastic (MP) contamination in soils, offering non‐destructive 3D visualization and quantitative analysis of particles embedded in complex matrices. This study evaluated its applicability by mixing plastic fragments (PET, PEHD, PS, and PP) with humus‐rich and sandy soils collected from environment. Scanning was performed using a Phoenix V|tome‐x M system, and image datasets were processed with segmentation and morphological filters to reduce artifacts. All fragments were successfully detected, and high‐resolution 3D models were reconstructed. MicroCT‐derived measurements of surface area and volume showed strong agreement with manual estimates ( R 2 = 0.96 and R 2 = 0.94, respectively). On average, segmentation produced 14 false positives per sample before post‐processing, with humus‐rich soils exhibiting ~5% higher error rates than sandy soils. Morphological descriptors (anisotropy, elongation, flatness) were systematically calculated, enabling shape‐based differentiation. And differences in gray‐level intensities among materials further indicated microCT's capacity for distinguishing polymer types. Overall, the study demonstrates that microCT can complement conventional methods by combining reliable quantitative data with morphological insights, strengthening its role in future assessments of MP contamination in soils.