Atmospheric microfibrous deposition over the Eastern Red Sea coast

Area of Science:

• Environmental Science
• Atmospheric Science
• Materials Science

Background:

• Atmospheric transport is a key pathway for microplastic dispersion.
• Fibrous microplastics (MFs) are common but often misidentified, potentially overestimating plastic MFs.
• Natural MFs are underreported in microplastic studies, with unclear environmental risks.

Purpose of the Study:

• To investigate the abundance, polymer composition, and deposition rates of airborne MFs.
• To assess the origin and transport of airborne MFs in the Eastern Red Sea.
• To differentiate between plastic and natural MFs in atmospheric samples.

Main Methods:

• Collection and analysis of airborne MFs in a coastal residential area.
• Fiber length measurement and polymer identification using analytical techniques.
• HYSPLIT backward trajectory analysis to determine air mass origins and transport pathways.

Main Results:

• Airborne MFs ranged from 183 µm to 11,877 µm in length.
• Plastic MFs accounted for 10% of identified MFs, with polyester as the predominant polymer (81.25%).
• Estimated mean atmospheric microfibrous deposition was 70 MFs m⁻² d⁻¹, including 8 plastic MFs m⁻² d⁻¹.

Conclusions:

• Airborne MFs are present in the Eastern Red Sea region, with a notable fraction being plastic.
• Local and regional air masses contribute to the deposition of MFs, highlighting atmospheric transport mechanisms.
• Further research is needed to understand the environmental risks posed by both natural and plastic airborne MFs.