Microplastics retained in Artic Ocean ice released by Global Warming

When sea ice forms, eliminates and concentrates particles from the water column, staying retained in the ice until it melts. Small plastics fragments (<5mm of diamenter), known as “microplastics” are an example of particles that can accumulate on ice. The principal origins of microplastics that are being accumulated in the oceans are micro spheres used in cosmetics, fibres released through washing machines and the fragmentation of bigger plastics found in the oceans. Arctic Ocean ice samples analysis collected at places distanced by km shows that the abundance of microplastics retained in ice is substantial.

a) Location of ice samples collected in Arctic to microplastics concentration analysis. b) ice sample being collected during NASA Icescape expedition during July of 2010. (image provide by D. Perovich, CRREL)

Microplastics concentrations in Arctic Ice are higher than those found in North Atlantic (North of Scotia) or in the subtropical waters from South Pacific. Polymers [1] identified are used in a range of domestic and industrial activities. However isn’t yet possible to be sure of the microplastics’ origin in the Arctic Ice due to the fact it has contact with different rivers and oceans.

Total number of microplastic particles by liter of sea water, according to polymer type and sample location

In the last years the Arctic Ocean fusion have raised to minimum historic levels on sea ice extension, as happened at September of 2012. If this tendency remains it is estimated that in the next decade can be released to the ocean more than 1 trillion of microplastics. Ambient consequences aren’t yet completely known but is clearly that these particles are ingested by a huge range of marine organisms including commercial species.

[1] a complex plastic constituted by simple molecules from different chemical reactions. Polymers are present in every person life for having a huge utility (domestic and industrial). Some variations are applied in plastic production (e.g. PVC, Teflon); synthetic fibres production (Nylon, Polyester. Dacron); Tires restoration; electric isolators (rubbers) and thermoplastics (CD’s, PET bottles, toys, cars,…)


Source: Obbard, R. W., Sadri, S., Wong, Y. Q., Khitun, A. A., Baker, I., & Thompson, R. C. (2014). Global warming releases microplastic legacy frozen in Arctic Sea ice. Earth’s Future, 2(6), 315-320. doi: 10.1002/2014EF000240

Author: Patrícia Azinhaga