The vast expanse of the ocean holds a hidden crisis. A new study, published in Nature by researchers from Utrecht University and the Royal Netherlands Institute for Sea Research (NIOZ), has revealed that tiny plastic fragments, less than a micrometer across, may significantly outnumber larger plastic particles.
These nanoplastics are polluting the North Atlantic Ocean to a shocking extent. They could potentially constitute the dominant fraction of marine plastic pollution by mass.
THE PARADOX OF THE “MISSING PLASTIC” SOLVED
The study was led by a team from Utrecht University. It utilized high-resolution imaging and chemical filtering techniques. These techniques were applied on samples collected from varying depths. The samples came from 12 sites in the North Atlantic. Nanoplastics, defined as particles smaller than one micrometer—a fraction of the thickness of a human hair—are notoriously difficult to detect.
The analysis provided a clear and alarming finding. It estimated that the North Atlantic Ocean contains approximately 27 million tonnes of nanoplastics. This is a staggering amount. It represents roughly a tenth of the entire volume of trash thrown away in the United States each year.
This estimate shows that there is more plastic in the form of nanoparticles floating in this part of the ocean. This is more than the larger micro or macroplastics in the Atlantic. It exceeds even all the world’s oceans,” stated biogeochemist Helge Niemann of Utrecht University and NIOZ.
This immense amount provides a crucial answer to the long-standing “paradox of the missing plastic.” It suggests that a significant portion of the plastic waste expected to be found in the oceans has simply broken down into these minuscule particles. These particles were previously unquantified.
UBIQUITOUS AND UNDERESTIMATED
The study identified common plastics used in bottles, cups, and films. These include polyethylene terephthalate (PET), polystyrene (PS), and polyvinyl chloride (PVC). However, researchers noted a surprising absence of polyethylene and polypropylene, which are ubiquitous in the environment. The team suggests these plastics may be masked by organic particles. It is also possible that current analysis techniques are not yet sensitive enough to detect them in this size fraction.
Nanoplastics were found at all surveyed depths. They were particularly concentrated near coasts (due to river and runoff contamination) and within the subtropical gyre, a known area of swirling currents that traps and breaks down larger plastics into smaller pieces.
A NEW FRONTIER OF ECOLOGICAL RISK
The findings underscore the sheer scale of the ecological problem posed by plastic waste. The precise extent to which nanoplastics harm marine ecosystems remains unclear, but their super-small size presents unique dangers.
“Nanoplastic and nanoparticles are so small that the physical laws governing larger particles often no longer apply,” explained chemist Dušan Materić. He is from the Helmholtz Centre for Environmental Research in Germany. Materić developed the innovative measurement method used in the study.
Because of their size, nanoplastics can interact with water, sediment, and other organisms in ways that larger microplastics cannot. They can easily penetrate biological barriers. Nanoplastics accumulate in living organisms. These particles potentially pose significant threats to marine life. Ultimately, they affect human health through the food chain.
THE PATH FORWARD: PREVENTION IS KEY
The researchers emphasized that removing nanoplastics from the ocean at this scale will be extremely difficult, if not impossible. Consequently, they are calling for urgent action to prevent plastics from entering the environment in the first place.
Materić noted that only a few years ago, the persistence of nanoplastics in nature was debated. “Many scholars continue to believe that nanoplastics are thermodynamically unlikely to persist in nature, as their formation requires high energy,” he said. “Our findings show that, by mass, the amount of nanoplastic is comparable to what was previously found for macro and microplastic—at least in this ocean system.”
The team suggests that future research must include sampling more ocean areas. It should scan for a wider variety of plastic types. Additionally, researchers need to investigate nanoplastics at different stages of degradation. This is essential to fully understand their impact on the marine environment.
