[from the INDEEP mailing list]
FYI – a recent paper focused on microplastics in deep sea sediments:
Woodall, Lucy C., Anna Sanchez-Vidal, Miquel Canals, Gordon LJ Paterson, Rachel Coppock, Victoria Sleight, Antonio Calafat, Alex D. Rogers, Bhavani E. Narayanaswamy, and Richard C. Thompson. (2014) The deep sea is a major sink for microplastic debris. Royal Society Open Science 1(4): 140317.