Image: Japan Agency for Marine-Earth Science and Technology (JAMSTEC).
A survey by the Global Oceanographic Data Center (GODAC) from Japan reports plastic pollution at depth, where more than 33% of the debris was macro-plastic, of which 89% was disposable, and these ratios increased to 52% and 92% respectively in areas deeper than 6000m. The deepest record was a plastic bag at 10898m in the Mariana Trench. Deep-sea organisms were observed in 17% of the plastic residue images, which include the attachment of plastic bags to chemosynthetic marine communities.
The full report can be read here:
Human footprint in the abyss: 30 year records of deep-sea plastic debris
English 
Norwegian 
