Presence of Microplastics in some commercial fish species in the northern Oman Sea, Iran

Nowadays, microplastics (MPs) are known as a new threat in the marine environment. This study investigates the occurrence, abundance, and characteristics of microplastics in the gills, gastrointestinal tract (GIT), and skin of five commercial fish species from the northern Oman Sea. Fish sampling was conducted in two time periods before the monsoon season (June) and during the monsoon season (September) based on habitat at three levels including demersal species (Psettodes erumei), benthopelagic species (Sphyraena putnamae, Parastromateus niger), and pelagic species (Ephippus orbis, Carangoides fulvoguttatus). MPs were found in all examined samples. The highest frequency of MPs was recorded during the pre-monsoon season in Psettodes erumei (154 items) and Ephippus orbis (139 items) in the monsoon season. Additionally, gills and GIT contained the most MPs in the seasons, respectively. MPs were characterized based on their physicochemical attributes using a stereomicroscope and Raman spectroscopy. The results showed that fibers were the most prevalent shape, and blue was the dominant colors. Predominant MPs ranged in size from 200-500 µm. Polypropylene (PP) and Polyvinyl chloride (PVC) were the most common polymers detected. The findings of this study not only highlight the widespread presence of MPs contamination in the study area but also enhance understanding of the environmental impacts of plastic waste on marine ecosystems, food webs, and potential consequences for human health.<br/><br/>Keywords: Microplastics, Commercial fish, Raman, Oman Sea, Iran.