Microplastic pollution in seawater, sediment and gastrointestinal tract of fishes of the North-Eastern Mediterranean sea

KEREM GÖKDAĞ

Microplastic pollution in seawater, sediment and gastrointestinal tract of fishes of the North-Eastern Mediterranean sea

Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Deniz Bilimleri Enstitüsü, Deniz Biyolojisi ve Balıkçılık Anabilim Dalı, Türkiye

Tezin Onay Tarihi: 2017

Tezin Dili: İngilizce

Öğrenci: KEREM GÖKDAĞ

Danışman: AHMET ERKAN KIDEYŞ

Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu

Özet:

Marine litter and microplastic pollution is a growing problem for the world and Turkish seas. In this study, the levels of microplastics in surface water, water column, sediment as well as in fish digestive system from the northeastern Mediterranean Sea were studied in 2015 and 2016. The impact of virgin microplastics on seabream juveniles was also investigated at the laboratory. Number of microplastics in surface water were between 16339 and 520213 particles km-2 in 2015, and, between 39559 and 1043675 particles km-2 in 2016. Although size range of microplastic particles was various, 94% of microplastic particles were between 0.1 and 2.5 mm in size. In 2015, a total of 1337 fish individuals encompassing 28 species (14 families) and in 2016, 175 individuals encompassing 2 species (2 families) were collected. A total of 1822 microplastic particles were extracted from stomach and intestines of fish specimens in 2015. In our study, 58% (771 specimens) and 53% (92 specimens) of all individuals contained microplastic particles either in the stomach or intestine in 2015 and 2016, respectively. These are among the highest values compared to those reported in the literature. After the microplastic feeding experiment in adult gilt-head seabream (Sparus aurata), accumulation of 6 common types of microplastics in gastrointestinal organs or to translocate to liver and muscles were monitored and recorded. However, ingestion of virgin microplastics did not induce stress, altered growth rate, caused pathology, or caused microplastics accumulation in gastrointestinal tract of fish.