Microplastics in sediments and fish from the Red Sea coast at Jeddah (Saudi Arabia)

Environmental context Millions of tons of plastic debris are present in the marine environment. This study addresses the issue of microplastics in nearshore sediment and fish sampled from the Saudi coastal waters of the Red Sea. The results show that the sediments of all analysed stations contained microplastics, and microplastic particles were detected in almost half of the 140 sampled fish. Abstract The amounts of microplastics in sediment samples obtained from four stations along the Jeddah coast were shown to range from not detected to 119 particles kg-1 wet sediment. Four classes of microplastic particles in the sediment, that is, fragments, granules, foams and fibres, were characterised by fluorescence microscopy. Microplastics of various forms and sizes were also identified in 44 % of the 140 sampled fish (6 local species) in amounts ranging from not detected to 30 microplastic particles per individual. Polyethylene terephthalate and vinyl chloride-vinyl acetate copolymers were the dominant polymer types in the sediment samples identified by Fourier-transform infrared spectroscopy (FTIR) analysis, while polystyrene, polyethylene and polyester were the dominant polymer types detected in fish. FTIR analysis showed that the most detected fibres were made of polyester. The results of this study emphasise that microplastic pollution represents an emerging threat to the marine environment of the Red Sea. The results of this study provide useful background information for further investigations and provide an accurate overview of the microplastics distribution in the marine environment of the Saudi Red Sea.