Detection of Microplastics in Turkish Salmon Purchased from Supermarket

Microplastics (MP), which enter the aquatic environment by taking resources from the breakdown of large-sized plastics and various products, pose serious problems for the environment. Microplastics mixed into water sources can harm both water quality and aquatic life. Like many organisms, fish cannot distinguish small size (˂5 mm) microplastics and can ingestion them. Aquatic products that ingest microplastics along with the food chain, may not be suitable for consumption by humans. In this study, the extent to which large-sized rainbow trout, previously known as Black Sea Salmon and later renamed as Turkish Salmon exposed to microplastics in the aquatic environment was examined. Within the scope of the study, 5 whole and unprocessed Turkish Salmon were purchasedfrom the fish section of the supermarket. The digestive system of the fish was removed and potassium hydroxide (KOH) solution was added to organic tissue samples for microplastic analysis. The resulting organic solution was filtered to ensure that microplastics were retained on the filter paper. Filter papers were examined under a microscope. The mean length and weight of the fish were calculated as 43.40±0.91 (33.3- 48.5) cm and 1078.8±109.1 (724-1298) g, respectively. It has been determined that the digestive system of all fish purchased from the market is contaminated with microplastic. While a total of 115 microplastics were counted in the digestive systems of all samples, the abundance of microplastics varied between 14-31 MP/individual (mean 23±8.6 MP/individual). Microplastics were classified as fibril (thin or fibrous, flat plastic), fragment (hard, rough plastic), film (thin, flimsy plastic), foam (light, sponge-like plastic) and pellet (hard, round plastic) types. All particles were also classified according to color and size (˂0.1 mm, 0.1-0.3 mm, 0.3-0.5, 0.5-1.0 mm, 1.0-5.0 mm). Accordingly, the dominant characteristics of the detected microplastics were fibril type (73.0%), size between 0.1-0.3 mm (29.6%), elongated shape (64.3%) and blue and black colors (42.6%). This study showed that Turkish Salmon were exposed to microplastics originating from the aquatic environment that they live in.