Core samples from the seabed in Greenland provide the first historical overview of plastic pollution

By filling the 850m deep seabed in Disco Bay off the west coast of Greenland, researchers at the University of Copenhagen have won the first historical record of plastic pollution in Greenland. The new data suggest links to local socioeconomic development and represent steps to developing a common method for analyzing and mapping global microplastic pollution.

Using so-called submarine coring, somewhat similar to the ice-core drilling techniques used by glaciologists, researchers at the University of Copenhagen have collaborated with colleagues at the University of Aarfs to achieve the first historical record of plastic pollution on the seabed in Greenland. This study has been published in the Journal Communications Earth & Environment.

This record shows that microplastic accumulation has increased and significant fluctuations in the seabed since the 1950s. Although certain environmental conditions such as freezing weather and glacial discharges may play a role, interestingly, such an increase and decrease in plastic accumulation is also consistent with Greenland’s historic socioeconomic development.

“Our data shows a significant increase in the amount of plastic accumulated on the seabed, along with the consent between construction projects and other socioeconomic events that took place locally in Greenland during the country’s modernization. As a plastic pollution researcher, we can use this knowledge to reassess the causes of plastic,” says Ph.D. Cara Palga Martinez, the Department of Geoscience and Natural Resources Management, currently a postdoctoral student at McGill University in Canada.

The general view was that most of the plastic comes to the Arctic through the currents, but new data highlights that local sources also play an important role. Researchers say this knowledge will help improve global data on plastic pollution.

“There is a strong desire among scientists to obtain high quality data on marine plastics, so there is a good overview of the plastic pollution problem and is also developing a model to monitor where trends are heading. For the first time, this research project is giving a historical overview of this doctorate in plastics. Management.

This achievement helps drive new solutions by documenting the wide distribution of plastics throughout the production history.

“It’s important to show that plastic is heading towards the seabed. Our actions have a direct impact on our environment. We continue to see evidence of the negative impact of plastic on the health of our ecosystems (and humans) and this is a reality now, and we need to explore the scope necessary to provide evidence,” says Post.

How to follow

By analyzing the total contents of the sample, the researchers developed sophisticated methods in marine sediments and methods for identifying plastics by their polymer composition.

Packing the tubes into the seabed allowed the researchers to retrieve the seabed core for analysis. These samples were dated using radionuclide dating, in which disintegrating isotopes were measured to determine the age of the material.

Slicing the core into ones that correspond to a relatively short period of time and separating microplastics from the seabed components (sand, clay, organic debris, etc.) allows you to compare the chemical composition of the plastic with libraries of known plastics of various ages.

Finally, matching the microplastic type with the age of the extracted seabed sediments allowed us to build a record in history.

Researchers say that such systematic improvements will play a greater role in understanding plastic pollution in the world’s oceans, and could be applied in many other places around the world to provide more tidy and more consistent global data.

“When we meet to communicate results in the science community, we need to be able to “speak the same language.” So broadly applicable methods and transparency regarding the characteristics of research sites are important so that results can be adjusted across the world and across the lab,” says Postth.

Tangible evidence of the Anthropocene

The so-called Anthropocene refers to the period of recent history of Earth, when human activities influenced the climate and ecosystem of our planet. This concept has become an accepted term in cultural and social debates, but as a scientific concept it is controversial.

“That’s not an accepted geological period, but the accumulation of plastics on the seabed has become a very specific part of that debate, as there is undeniable evidence that humanity left a geological mark even in this remote area,” Postth says.

Marine plastic pollution leaves a measurable human trace on a global and historical scale, and we are beginning to understand the impact we are now.

“When assessing the outcomes of our behavior as a species of biosphere we live in, we need to understand the geological history of our existence. That’s why historical records of plastic pollution, like those created in West Greenland, are important,” the researchers conclude.