Microplastics and nanoplastics on Mt. Everest

<h2>Summary</h2> Microplastics (MPs) and nanoplastics (NPs), recognized as contaminants of emerging concern, have been identified even in remote regions. However, their abundance, distribution, and environmental impacts on Mt. Everest remain largely unexplored. This study investigates the abundance of MPs in soil, water, atmospheric, snow, yak dung, and road dust samples on Mt. Everest, with average concentrations of MPs being 65.0 items·kg⁻¹, 3.8 items·L⁻¹, 6.9 items·(m²·d)⁻¹, 95.0 items·L⁻¹, 36.5 items·kg⁻¹, and 23.4 items·kg⁻¹, respectively. For the first time, the abundance of NPs on Mt. Everest is quantified, revealing concentrations of 4.9 mg·kg⁻¹ in soil, 1.9 mg·L⁻¹ in water, and 0.13 items·(m²·d)⁻¹ in atmospheric samples. Notably, polyethylene is the predominant polymer type, accounting for 86.0% (w/w) of all detected NPs. Additionally, our data suggest that MPs exhibit greater bacterial community diversity and evenness compared with those in surrounding soil environments. This work provides quantitative evidence of MNP pollution on Mt. Everest.