Morphodepositional Insights into Microplastics and Microfibers in Beach Sediments of the Vesuvian Coast, Southern Italy

The presence of Microplastics (MPs) and microfibers (MFs) in coastal environments is a significant environmental concern. MPs, defined as particles between 1 μm and 5 mm, and MFs, elongated fibers with a length-to-width ratio between 3:1 and 5:1, persist in sedimentary systems due to their durability and resistance to degradation. The physical and chemical properties of these particles, such as particle size, shape, surface roughness, and degree of alteration, influence their transport, deposition, and interactions with the environment. These characteristics also affect their fate and bioavailability for marine organisms. Building on a novel green protocol developed by Rossi et al. (2024) [1] for identifying MPs and MFs in marine sediments, this study investigates the morphodepositional dynamics of these pollutants along the Vesuvian Coast, southern Italy. The research utilizes a combination of stereomicroscopy for particle morphology, scanning electron microscopy (SEM) for detailed structural analysis, and granulometric and grain morphoscopic methods for characterization.

A key innovation of this study is the development of an eco-friendly protocol that combines optical microscopy and statistical analysis, eliminating the need for traditional methods such as chemical digestion and density separation. This approach provides a more sustainable and precise method for particle identification and analysis. Results revealed a predominance of MFs over MPs across all sites, with significant spatial variability in their characteristics. MFs near the shoreline were longer (mean length of 1,437 μm) and less weathered compared to those found further inland, where smaller, more degraded particles were present due to prolonged exposure to environmental stressors. MPs were primarily angular fragments closely associated with sediment grains, while fibrous MPs adhered to or coiled around the grains, influencing their movement during littoral drift. Pollution levels varied significantly across the study sites. San Giovanni a Teduccio beach, adjacent to industrial facilities and wastewater outlets, exhibited the highest levels of contamination, while beaches further south, such as Torre del Greco, showed lower levels, reflecting the role of longshore currents in dispersing pollutants.

The statistical and morphodepositional analysis applied in this study provides a deeper understanding of the environmental processes that govern the distribution and alteration of MPs and MFs in coastal systems. These insights can help improve strategies for pollution management and the preservation of marine ecosystems. The innovative protocol developed in this research offers a valuable tool for future studies of MPs and MFs, contributing to more sustainable environmental monitoring practices.

 

Reference:
[1] Rossi, M., et al. "A new green protocol for the identification of microplastics and microfibers in marine sediments, a case study from the Vesuvian Coast, Southern Italy", 2024. Journal of Hazardous Materials, 477(7), 135272. URL: https://doi.org/10.1016/j.jhazmat.2024.135272