Microplastic Contamination in Snow from Western Italian Alps

Abstract

Recent studies have documented the presence of microplastics (MPs) in remote areas, including soils or sediments collected in mountain and glacier environments, but information on their presence in snow is scant. The present study aimed at exploring the presence of MPs in residual snow collected in four locations of the Aosta Valley (Western Italian Alps), with different accessibility and human presence. Overall, the µ-FTIR analyses confirmed the presence of 18 MPs in snow, 7 (39%) items were fibres, while 11 (61%) were fragments. Polyethylene (PE; 7 MPs) was the main polymer, followed by polyethylene terephthalate (PET; 3 MPs), high density PE (HDPE; 3 MPs), polyester (2 MPs), while only 1 MP made by low density PE, polypropylene and polyurethane were found. The mean (± SE) concentration of MPs in snow ranged between 0.39 ± 0.39 MPs/L and 4.91 ± 2.48 MPs/L, with a mean of 2.32 ± 0.96 MPs/L for the sampling locations. The concentration of MPs did not statistically differ among locations. Our results suggest that MPs presence in high-mountain ecosystems might depend on deposition through atmospheric precipitations or local sources due to human activities. For these reasons, policies aiming at reducing plastic use and dispersal in mountain areas may be effective in preventing local MP contamination.

Presence of nanoplastics in rural and remote surface waters

“…This is in agreement with research demonstrating that acidified lakes waters [51] in the area were caused by moderately high levels of atmospheric acid deposition [52], the majority of which was the result of long-range pollutant transport from industry in the UK and central Europe [53]. Longrange atmospheric transport of microplastics has been demonstrated over distances of hundreds and even thousands of kilometres, and modelling suggests that nanoplastics can be transported over greater distances [12,14,18,20,[54][55][56]. Thus, it is clear that atmospheric transport is extremely important in the global plastic cycle.…”

“…Microplastics have already been found in many environments, including marine waters, aquatic sediments, freshwater systems, soils, and the atmosphere. These reports span both urban and remote locations [8,[12][13][14][15][16][17][18]. However, the research field is still relatively young and our ability to quantify ecosystem microplastic budgets, including major pools, sources and sinks, is still under-developed [19].…”

Current status and future perspectives of microplastic pollution in typical cryospheric regions

“…Studies in the remote cryospheric regions are limited, and the protocols used for collecting and pretreating snow and ice before the measurement of microplastics is diverse and unstandardized. Surface snow samples are usually retrieved with a steel spoon and placed into pre-cleaned glass or metal containers by operators that are dressed in 100% cotton clothes, and sampling is performed downwind (Bergmann et al, 2019;Parolini et al, 2021) (Table 1). Snow samples have been collected from the surface of the Andes glacier before being placed into pre-cleaned plastic bags, washed three times with Milli-Q water (18 MΩ cm), and dried at room temperature (Cabrera et al, 2020).…”

“…Aluminum oxide filters, nitrocellulose membranes, glass microfiber filters, or PTFE filters with different pore size (0.2 μm, 0.45 μm, 0.7 μm, or 1 μm) are usually used. Saturated sodium chloride (NaCl) solutions are generally used for density separation of microplastics from snow and ice samples, and H 2 O 2 solutions have been used to remove the organic matter and biofilms that are attached to the plastic surface (Ambrosini et al, 2019;Parolini et al, 2021;Peeken et al, 2018).…”

“…intensively investigated. Recent research has highlighted the presence of microplastics in the snow and ice of remote cryospheric regions, with focus on the distribution, abundance, sources, and transport of microplastics in snow and ice (Bergmann et al, 2019;Parolini et al, 2021;Stefánsson et al, 2021;Zhang et al, 2021). However, in-depth exploration of the occurrence, behavior, and fate of microplastics in the cryosphere lacks comprehensive evaluation compared to that conducted in the marine or atmospheric environments (Brahney et al, 2021;Hale et al, 2020;Lima et al, 2021;Zeng, 2018).…”