Microplastics, tiny fragments of plastic measuring less than five millimetres that come from packaging and other pollution sources, have been detected in the “pristine” air of the French Pyrenees.
That’s according to a new article published in the journal Nature Communications on Tuesday.
An international research team which included scientists from the French National Centre for Scientific Research (CNRS), Universite Grenoble Alpes and the University of Strathclyde in Scotland, analyzed the composition of air captured weekly by a pump installed at the Pic du Midi Observatory (PDM) in the French Pyrenees.
The observatory is considered a “clean station” because of its limited influence by “local climatic conditions or the environment,” according to the paper.
The scientists tested 10,000 cubic metres of air each week collected at PDM, at 2,877 metres above sea level, between June and October of 2017.
The paper says microplastics were detected in all samples analyzed.
The researchers said the approximate concentration of one particle per four metres cubed.
These results “exhibit true free atmospheric transport of microplastic” and “high altitude microplastic particles,” the paper suggests.
The researchers used mathematical modelling of air mass trajectories to identify several areas from which the microplastics could have derived.
“Potential source areas identified include locations across North Africa, Spain, Portugal, France, UK/Ireland and as far as the USA/Canada, as well as the Mediterranean and Atlantic Oceans,” the report reads.
The authors of the article said while atmospheric microplastics “have been discovered in the planetary boundary layer, their occurrence in the free troposphere is relatively unexplored.”
“Confronting this is important because their presence in the free troposphere would facilitate transport over greater distances and thus the potential to reach more distal and remote parts of the planet,” the report reads.
