Microplastic Composition and Distribution Across the Pelagic and Benthic Zones of the Jordanian Gulf of Aqaba, Red Sea

Global concerns regarding microplastics emerging in the environment have been raised recently. Using samples collected during the OceanXplorer mission in Aqaba, we explored the depth-based and regional variations of microplastics across pelagic and benthic zones. Microplastics (63.0-950.0 µm) from the surface seawater, middle seawater, bottom seawater, and deep-sea sediment were quantified and identified using a dissecting microscope and Fourier Transform Infrared microscope (µ-FTIR). The results revealed that the average abundance of microplastics was 6.7 ± 6.05 particles L −1 in the pelagic zone and 2900 ± 1650 particles kg −1 in the benthic zone. A size gradation of microplastics was observed across depths from 5 to 840 m, accompanied by a shift in particle types: fragments were the most common in the benthic zone, whereas fibers dominated the pelagic zone. µ-FTIR analysis identified the presence of the following polymers: polyethylene (PE), polyvinyl chloride (PVC), polyamide 6 (PA 6), and polypropylene (PP). These findings establish baseline data for future monitoring and management efforts addressing microplastic pollution in the Gulf of Aqaba.