Why nanoplastics might be a bigger problem than microplastics

Microplastics have become a growing environmental concern in recent years, but scientists say a smaller, less-studied category of plastic pollution could present an even greater challenge: nanoplastics. New research has now detected these particles in Antarctic soil for the first time, in one of the coldest and driest regions on Earth.

Nanoplastics are plastic particles measuring less than one micrometre across. Because they are much smaller than microplastics, they can remain suspended in the air more easily, pass through cell membranes, and carry other pollutants on their surfaces — properties that make them harder to track and potentially more harmful than their larger counterparts.

The study, published in Scientific Reports, found nanoplastics in soils from the McMurdo Dry Valleys, including fragments from tyre wear and five other common plastics used in everyday products. Researchers say the findings point to a combination of local human activity and long-range atmospheric transport as likely sources, adding to earlier detections of nanoplastics in remote locations such as Greenland and the Alps.

Researchers collected soil samples from the Taylor and Wright valleys during January 2023, analysing 13 topsoil samples along with four deeper samples. Nanoplastics were detected above the method’s detection limit in 54 percent of the topsoil samples, with the highest concentration reaching 295 nanograms per gram of soil, and were also found in half of the deeper samples tested, though at lower concentrations — evidence, researchers say, that plastic contamination may now be present even in the Antarctic interior.