Are there really 46,000 pieces of plastic per square kilometer of the worlds oceans?
We were unable to find a reference for this figure. The closest we could find was a UNEP report published in 2005 that mentions a figure of 13,000 pieces of litter per square kilometer; however there is no source or referenced study for that figure (UNEP, 2005). To date, there has not been a comprehensive marine debris abundance assessment for the world’s oceans, or even for a single ocean. This is partly due to the lack of a standardized at-sea plastic marine debris monitoring method. The NOAA Marine Debris Program is working together with the University of Washington, Tacoma to develop an agreed-upon standard methodology for pelagic marine debris monitoring to help us compare sampling sites and acquire reliable estimates of plastic debris in the oceans.
