Scientists have identified the highest recorded microplastics ever found on Earth – at an altitude of more than 8,000 metres, close to the summit of Mount Everest.
Samples collected on the mountain and in the valley below it revealed substantial quantities of polyester, acrylic, nylon, and polypropylene fibres.
The materials are increasingly being used to make the high performance outdoor clothing commonly used by climbers, as well as the tents and climbing ropes used in attempts to climb the mountain.
As a result, researchers have suggested the fibres – the highest of which were found in samples from the Balcony of Mount Everest, 8,440 metres above sea level – could have fragmented from larger items during expeditions to reach the summit.
However, they have also surmised the plastics could have been transported from lower altitudes by the extreme winds which regularly impact the mountain’s higher slopes.
The research, published in One Earth, was led by researchers from the University of Plymouth’s International Marine Litter Research Unit, working with colleagues from the UK, USA and Nepal. It was supported by the National Geographic Society and Rolex.