Update: DK user New Minas notes that the researchers used a much finer screen size to collect their samples so comparison with the great Pacific garbage patch may be comparing apples and oranges. The screen was finer by greater than a factor of 1,000. It may be impossible to compare samples from ice cores subjected to a very fine screen with samples taken from the open ocean using a relatively coarse screen.
Moreover, the source article apparently misquoted one of its references on the total volume of Arctic sea ice. The number is apparently 500 times the 2012 sea ice minimum, which is clearly not possible. Kudos to New Minas for this excellent unsolicited peer review of the source article.
Polar scientists estimate that rapid warming of the Arctic is going to melt about
2,000 4 trillion cubic meters of sea ice by 2040. If the particle density is about 50 particles per cubic meter, two hundred-trillion plastic particles will go back into the water. This plastic soup will flow into the north Atlantic ocean over the next 3 decades. How this soup of plastic micro-particles will affect sea life has not yet been determined. Plastic is known to be taken up by marine organisms and birds with a variety of detrimental consequences.