Occurrence of microplastics in the gastrointestinal tracts of edible fishes from South Indian Rivers

Abstract The occurrence of microplastics MPs in the gastrointestinal (GI) tracts of the five different fish species (Chanos chanos, Chanda nama, Chelon macrolepis, Gerrus filamentosus, and Carangoides malabaricus) from the Kollidam River and Vellar River of Tamil Nadu, Southern India were evaluated. A maximum of 23 individual fishes was sampled from both Rivers and alkaline digestion was performed to extract the MPs in the GI tract of fishes. The results revealed that a total of 315 MPs were isolated from the GI tracts of all fishes sampled from both Rivers with fibres and fragments. The average size of ingested MPs was ranged between 108.72 to 129.11 µm and 181 to 284 µm in the fishes sampled from Kollidam and Vellar River respectively. In the morphological examination of MPs, fishes from both Rivers showed the maximum level of fibres, followed by fragments. The colour pattern of the ingested MPs was dominated by blue, transparent, red and other colours in both rivers. In this study, MPs in the GI tract of fishes indicated that the MPs pollution in studied Rivers can cause significant threats to aquatic fauna.