Microplastics in fishes from an estuary (Minho River) ending into the NE Atlantic Ocean

Wild fish (Cyprinus carpio, Mugil cephalus, Platichthys flesus) from an estuary of the NE Atlantic coast were investigated for plastic contamination (N = 128). From the 1289 particles recovered from fish samples, 883 were plastics. Among these, 84% were fibres and 97% were microplastics. Thirty-six polymers were identified. The number of microplastics (mean +/- SD) per individual fish (MP/fish) was 8 +/- 6 in C. carpio, 10 +/- 9 in M. cephalus and 2 +/- 2 in P. flesus. The means of MP/fish per body site were 6 +/- 7 in gastrointestinal tract, 0.5 +/- 1.1 in gills, 0.3 +/- 0.7 in liver and 0.6 +/- 1.2 in muscle samples. A few large fibres in liver (< 4841 mu m) and muscle (< 5810 mu m) samples were found. The results evidence the existence of high fish contamination by microplastics and reinforce the need of further research on plastic pollution in estuaries.

Automated summary

Wild fish from an estuary of the NE Atlantic coast were found to be heavily contaminated by microplastics, with a majority of them being fibers and particularly high concentrations in the gastrointestinal tract. This highlights the urgent need for further research on plastic pollution in estuaries.