For the first time nanoplastic pollution has been detected in the Arctic and South Pole regions to the core, indicating that plastic contamination is already very severe and is spreading worldwide.
Nanoparticles are smaller and more toxic than microplastics. Worryingly, the impact of both on human health is so far unknown.
Core analysis of the Greenland ice sheet shows that nanoplastic contamination has been contaminating the remote region for at least 50 years. The researchers were also surprised to find that a quarter of the particles came from vehicle tires.
Very light nanoparticles are thought to be blown into Greenland by winds from cities in North America and Asia. The nanoplastics found in sea ice in the McMurdo Sound in Antarctica are likely to have been transported by ocean currents to remote continents.
"Plastic is part of the mix of chemical pollution that surrounds the planet, which has crossed the safe limit for humankind," the scientists said, as quoted by The Guardian.
Plastic pollution has been found from the summit of Mount Everest to the depths of the oceans. People accidentally consume and inhale microplastics. Another recent study found that the particles cause damage to human cells.
"We detected nanoplastics in the farthest corners of the Earth, both in the south and north polar regions. Nanoplastics are very toxicologically active compared to, for example, microplastics, and that's why this is so important," said Dušan Materić of Utrecht University in the Netherlands and who led the study. .
The Greenland ice core is 14 meters deep, representing a layer of snowfall since 1965. "What surprised me was not that we detected nanoplastics there, but that we detected them all the way to the core. So even though nanoplastics are considered a new pollutant, they have actually been around for some time. decades," said Materić.
Previously, microplastics have been found in Arctic ice. But the Materi team had to develop a new detection method to analyze much smaller nanoparticles.
Previous work has also shown that worn dust from tires may be a major source of marine microplastics and this study provides concrete evidence.
The new study, published in the journal Environmental Research, found 13 nanograms of nanoplastic per milliliter of ice melted in Greenland but four times as much in Antarctic ice. This may be because the sea ice formation process concentrates the particles.
In Greenland, half of the nanoplastics are polyethylene (PE), a material used in single-use plastic bags and packaging. One-quarter is tire particles and one-fifth is polyethylene terephthalate (PET), which is used in beverage bottles and clothing.
Half of the nanoplastics in the Antarctic ice are PE as well. However, polypropylene is the next most common plastic material, used for food containers and pipes. No tire particles were found in Antarctica further away from populated areas. The researchers sampled only from the center of the ice core to avoid contamination, and tested their system with a control sample of pure water.
Previous studies have found plastic nanoparticles in rivers in England, seawater from the North Atlantic and lakes in Siberia, and snow in the Austrian Alps. "But we assume the hotspot is the continent where people live," said Materić.
"Nanoplastics have shown various adverse effects on organisms. Human exposure to nanoplastics can cause cytotoxicity and inflammation," the researchers wrote.
"The most important thing as a researcher is to measure (pollution) accurately and then assess the situation. We are in the very early stages of drawing conclusions. But it seems that, in all the places we have analyzed, it is a very big problem. How big? We don't know yet," he continued.
Research is underway on the health effects of plastic pollution and Dr Fay Couceiro is leading a new group of microplastics at the University of Portsmouth, UK. One of his first projects was to investigate the presence of microplastics in the lungs of patients with chronic obstructive pulmonary disease (COPD) and asthma.
The study will investigate whether a room that has recently been carpeted or vacated, which can have a lot of lint in the air, triggers the patient's condition.
"In addition to the environmental damage caused by plastics, there is growing concern about the impact that inhaling and ingesting microplastics has on our bodies," Couceiro said.
His latest research suggests people may inhale 2,000-7,000 microplastics per day in their home environment. Prof Anoop Jivan Chauhan, a respiratory specialist at the University Hospital Portsmouth's NHS trust, said the data were really quite surprising.
"Each of us has the potential to inhale or ingest up to 1.8 million microplastics every year. Once (these materials) are in the body, it's hard to imagine them not doing any permanent damage."