# How much plastic settles to the bottom of the oceans each year?

This article says that 5 to 13 million metric tons of plastic go into the ocean every year. In the study At what point do floating plastics sink?, they give an estimate of the weight needed to sink plastics. They reference the paper Assessing marine debris in deep seafloor habitats off California, which assesses the amount of plastic debris that has settled to the bottom of the ocean off the coast of California. Given this information as a starting point... How much plastic settles to the bottom of the oceans each year?

• To answer this properly, we need to know how much plastic enters the oceans each year. Probably the largest proportion of it settles to the sea floor at one point of time. If we are (are we?) in situation with a steady state of plastic amount in the water column, the amount of sinking plastic should be also in the steady state. I think (personal feeling; worked a bit in this field four years ago) beaching, degradation and eating by animals together amount for less than the sinking. Therefore, I would expect that more than half of the released plastic settles to the seafloor. Feb 11 '18 at 11:22
• I don't have references for my conclusion => hence, just a comment an no answer. Feb 11 '18 at 11:23
• @daniel.neumann - It clearly states that about 5 to 13 million metric tons of plastic enter the ocean every year in the first sentence. Did you even read it? Feb 12 '18 at 13:32
• The input of 5 to 13 million metric tons per year is quite rough (and maybe the best estimate one can give in the moment). It is the same as when I would say that my age was approximately between 17 and 45 years. The given number is even rougher than my example because 1 year is 1 year (without time travel and relativity) but 1 kg of plastic items are not necessary like another 1 kg of plastic items (different shape, different material, different additives). Feb 12 '18 at 14:27

# About 18.2 million tons sink to the ocean floor.

Every year, an astonishing 260 million tons of plastic waste is produced, and about 10% of it ends up in the ocean. Over time, roughly 70% of the plastic that ends up in the ocean sinks to the ocean floor.

Therefore 18.2 million tons of plastic waste end up on the ocean floor.