Microplastics in sediments from Amazon rivers, Brazil.

We assessed the concentrations of microplastics in sediment samples collected in seven sites from Solimões, Negro and Amazon rivers, upstream and downstream the metropolitan region of Manaus. Concentrations ranged from 417 to 8178 particles/kg of dried sediment (microplastics: 0.063-5 mm), and from 0 to 5725 particles/kg of dried sediment (microplastics: 0.