Microplastics in snow of a high mountain national park: El Teide, Tenerife (Canary Islands, Spain)

Human activities have introduced high amounts of microplastics (MPs) into the atmosphere that can be transported long distances and be later deposited in terrestrial and aquatic ecosystems with precipitation (rain or snow). In this work, it has been assessed the presence of MPs in the snow of El Teide National Park (Tenerife, Canary Islands, Spain, 2150-3200 m above sea level) after two storm episodes (January-February 2021). The data set (63 samples) was divided into three groups: i) samples from accessible areas (after the first storm episode and in places with a strong previous/recent anthropogenic activity); ii) pristine areas (after the second storm episode, in places with no previous anthropogenic activity), and iii) climbing areas (after the second storm episode, in places with a soft re-cent anthropogenic activity). Similar pattern profiles were observed among sampling sites in terms of morphology, col-our and size (predominance of blue and black microfibers of 250-750 mu m length), as well as in composition (predominance of cellulosic-either natural or semisynthetic-, with a 62.7 %, polyester, 20.9 %, and acrylic, 6.3 %, microfibers); however, significant differences in MPs concentrations were found between samples collected in pristine areas (average concentration of 51 +/- 72 items/L) and those obtained in places with a previous anthropogenic activity (average concentration of 167 +/- 104 and 188 +/- 164 items/L in accessible areas and climbing areas, respectively). This study shows, for the first time, the presence of MPs in snow samples from a high altitude protected area on an in-sular territory and suggests that the sources of these contaminants could be atmospheric transport and local human outdoor activities.

Automated summary

Human activities have led to the introduction of significant amounts of microplastics (MPs) into the atmosphere, which can travel long distances and deposit in terrestrial and aquatic ecosystems through precipitation. This study examined the presence of MPs in snow samples from El Teide National Park, revealing similar pattern profiles and composition among sampling sites. However, significant differences in MPs concentrations were found between samples collected in pristine areas and those obtained in places with anthropogenic activity, indicating the influence of both atmospheric transport and local human outdoor activities.