Horizontal and Vertical Distribution of Microplastics in the Beach Sediments of Qatar

Dib, S., Veerasingam, S., Aboobacker, V.M., Al-Khayat, J.A., Sadooni, F.N., Al-Kuwari, H., and Vethamony, P., 2024. Horizontal and vertical distribution of microplastics in the beach sediments of Qatar. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 468-472. Charlotte (North Carolina), ISSN 0749-0208. Microplastic (MP) pollution in the Arabian Gulf has become an emerging environmental issue regionally and, a few studies have been carried out recently in the Gulf to identify its presence in the water, sediment and biota, and these studies have confirmed its presence. Sediment is considered as the main sink of plastics and other contaminants, causing ecological and biological consequences. Therefore, in the present study, we have investigated the horizontal and vertical distributions of microplastics in the coastal sediments of Qatar and assessed their ecological risks. Sediment samples, upto a depth of 25 cm with a spacing of 5 cm, were collected from twelve beaches along the Qatar coast during September 2019, and microplastics (MPs <5 mm) in the sediments were investigated. A total of 1915 MPs has been detected with different sizes, shapes, and colours. The mean abundance is 34.88 MPs/kg. The highest concentration of MPs is obtained at the surface layers, accounting for 85.48% of the total MPs abundance in all layers from 0 to 25 cm. The most abundant form of MPs found in the sediments are pellets, with approximately 95% of the pellets being black in colour, and their size ranging from 3000 to 4000 µm. The composition of MPs was detected through micro-Raman spectroscopy. PP and PE are the main polymers identified in the study which represent >60% of the identified MPs in the sediments. The abundance of MPs presented a clear decreasing trend with increasing sediment depths. This study shows that the usage of plastic products in the GCC region is negatively affecting the coastal region, thereby requesting for needed mitigation measures.