Greenland’s Seabed Provides First Historical Record of Plastic Pollution

A new study by scientists at the University of Copenhagen has given the first historical overview of plastic contamination in the seabed of Greenland. By sampling the seafloor in Disko Bay at a depth of 850 meters, researchers have been able to trace the deposit of microplastics back to the 1950s. As suggested by the discovery, plastic pollution is associated with local economic development and suggests the contribution of local and global sources to Arctic plastic pollution.

Tracing Plastic Pollution From Seabed Cores
Scientists employed seabed coring, an ice core drilling analogue, to extract sediment layers and measure their plastic composition. Radionuclide dating, which estimates material age through the measurement of decaying isotopes, dated the samples. Sectioning the cores into sections representing brief periods of time, scientists identified microplastic particles and contrasted their composition with identified plastic forms of varying ages. This enabled them to follow the build-up of plastic over time.

The research showed a consistent trend in plastic deposits since the mid-20th century with oscillations in line with Greenland's modernization. The research disproves the notion that the majority of plastic within the Arctic originates from oceanic currents and instead suggests that local sources are also considerable. The research also illuminates the development of plastic contamination sources and potentially enhances world statistics on ocean pollution.

Establishing a Universal Standard for Plastic Pollution Research
The research also created better methods for coring marine sediments and analyzing plastics based on their polymer content. These methods could be used to create a more uniform means of researching microplastic contamination globally. Researchers highlight the need to use standardized study methods to uniformize data across regions and improve understanding plastic contamination globally.

It is significant to discover long-term effects of plastic on the environment because continued pollution impacts on ecosystems and aquatic life. Presence of microplastics in Greenland's seabed contributes to evidence of increasingly significant human influences in the environment. The discovery serves to inform policymaking on minimal use of plastic waste and avoiding its effect in marine ecosystems. 

Plastic Pollution as Evidence of the Anthropocene
The research further advances evidence supporting and opposing the Anthropocene, a new era proposed based on human activities changing Earth's climate and ecosystems. Despite the geologists' resistance to adopt the term, seafloor accumulation of plastics presents tangible evidence of human trace. The research reaffirms that plastic pollution has in fact marked the world and, as an offshoot, even remote places. 

Conclusion
This study is a landmark contribution to plastic pollution history in the Arctic. Quantifying the actual mass of accumulated microplastics, the study calls for improved pollution management and international cooperation in minimizing plastic waste. More accurate techniques by the study also have the potential to standardize measurements of plastic pollution worldwide, which would ensure increased accuracy of ocean pollution.

Source: Communications Earth & Environment (2024). DOI: 10.1038/s43247-024-01768-y