Investigation of Microplastic Pollution in Sargassum sp. Macroalgae on Rocky Shores of Bushehr Province

Nowadays, the increase in microplastic pollution has become a global problem. The food chain can be polluted by the presence of microplastics in macroalgae. To measure the presence and amount of microplastics in macroalgae and water, sampling was performed from the rocky shores of Bushehr province during the winter season of 2021 and summer season of 2022 from four stations of Jofreh, Rishehr, Bojikdan, and Halileh. The result indicates the presence of microplastics in the macroalgae and the water, which were separated using a stereomicroscope. The microplastics were analyzed by FTIR-ATR device to determine the type of microplastic. The dominant species of the sampling stations were macroalgae Sargassum sp.Although, according to the results, the microplastic pollution in macroalgae samples was higher in the summer than in winter, the microplastic pollution in the water was more in the winter season. The average abundance of microplastics was calculated as 173±96.96 and 116.75±63.36 microplastics/kg in the summer and winter seasons, respectively. Jofreh and Halileh stations, with a mean frequency of 225±50.48 and 23±5.69 microplastics/kg, were the most polluted and clean stations, respectively. The sphere form of the microplastic fragments was more frequent after the fiber type. The results of the FTIR-ATR analysis showed that the microplastic polymers in Sargassum sp. and water were polyamide (nylon)˃ polystyrene˃ polyvinyl chloride,  respectively. Since the main activities that pollute the beaches of Bushehr province are fishing, shipping, tourism, etc., and they are more in the summer. So it can be seen as evidence for the results of this study.