Racing Ahead Towards Understanding the Potential Impact of Ski Waxes

Frank Dorman | Waters Corporation

In our previous post, we explored a non-traditional potential source of PFAS contamination in the environment—ski waxes. In this post, we delve into how to evaluate these materials and assess their environmental impact, which may be of ?concern for widespread contamination from their use.

Reports indicate that PFAS exposure, likely from the ski waxing process, has been found in serum samples of industry workers [Crawford 2022, Henn 2024]. While significant, this represents a more specific exposure route, affecting a smaller population subset. The broader question remains: how might the general population be exposed to these chemicals from use in these applications? What chemical complexity and concentrations might we find in environmental samples, and how can these be evaluated?

Where to Begin

Manufacturers of ski waxes do not disclose the exact chemical compositions of their products, citing proprietary advantages over competitors. Additionally, there are no real relevant regulatory controls on the use of these materials. Although the ski and ski racing industry has banned their use, and manufacturers have largely withdrawn them from commercial markets, detailed chemical composition data remains limited.

To investigate further, we need to sample potentially affected locations while maintaining proper scientific controls, including positive and negative samples. Additionally, historic wax samples can be obtained for analysis, but these must be handled with care to minimize cross-contamination in trace-analytical laboratories.

Obtaining Samples

For initial characterization, surface water samples were collected during the off-season at a New England ski area involved in high-level collegiate alpine racing. Sampling locations included:

• Above the start ramp, where final finishing and base overlays may be applied.
• Along ?the race slope, including the finish corral where racers rapidly stop.
• Down-gradient areas, including the snowmaking retention pond (the primary water source for snowmaking operations).

The down-gradient retention ponds create a "partially closed" system (author’s term) that recycles water annually to improve efficiency. Positive controls included laboratory reference materials, while negative controls included field blanks and samples taken from areas significantly upgradient from ski operations.

Analytical Methodology

Surface water samples were extracted using standard WAX SPE protocols [Waters Applications Note 720006808], isolating a broad range of expected compounds. Targeted analysis followed USEPA Method 1633 (or similar) [Waters Applications Note 720008117] to determine concentrations of an extended list of PFAS.

Non-targeted analysis employed high-resolution mass spectrometry (HRMS) with ion-mobility filtration [Waters Applications Note 7200082069]. These combined methodologies provided comprehensive characterization of both targeted and non-targeted PFAS compounds amenable to liquid chromatography (LC). Future work will address non-LC amenable compounds.

What Was Found?

In short: a significant presence of PFAS. Targeted analysis identified PFHpA in all extracted samples, along with PFBS, PFOS, PFHxA, PFOA, PFNA, PFDA, and PFTreDA, at levels exceeding background and negative control values.

Non-targeted analysis revealed additional complexity. A series of polyfluorocarboxylic acids with one fluorine substituted for hydrogen (H-PFAS) was detected. Notably, concentrations shifted toward shorter aliphatic chains as samples progressed towards the retention pond.

Furthermore, Figure 1 highlights a series of dioic acids identified and confirmed in the snowmaking retention pond. This raises the question: are these compounds migrating to the pond or forming there through transformation or degradation processes?

Next Steps

The findings indicate that PFAS are present in a location unlikely to be impacted by traditional sources, as discussed in the previous blog. To better understand the source, fate, and levels of these materials, further studies are necessary.

Subsequent work will include:

• Higher-density sampling.
• Soil and sediment sample collection.
• Analysis of ski wax samples to determine formulation details.

These studies may reveal a significant source of PFAS contamination in remote locations. Moreover, human exposure studies may be warranted. Stay tuned for the next blog post!

References:

Kathryn A. Crawford, Brett T. Doherty, Diane Gilbert-Diamond, Megan E. Romano and Birgit Claus Henn, “Waxing activity as a potential source of exposure to per- and polyfluoroalkyl substances (PFAS) and other environmental contaminants among the US ski and snowboard community”, Environmental Research, Volume 215, Part 3, December 2022, 114335, DOI: https://doi.org/10.1016/j.envres.2022.114335

Birgit Claus Henn, Emily R. Leonard, Brett T. Doherty, Sam Byrne, Nicola Hartmann, Adam S. Ptolemy, Shaké Ayanian and Kathryn A. Crawford, “Serum per- and polyfluoroalkyl substance (PFAS) levels and health-related biomarkers in a pilot study of skiers in New England”, Environmental Research, Volume 263, Part 2, 15 December 2024, 120122, DOI: https://doi.org/10.1016/j.envres.2024.120122

Waters Applications Note 720006808: Oasis WAX for Extraction of Per- and Polyfluorinated Alkyl Substances (PFAS) from Drinking Water in Accordance with EPA Method 533 | Waters

Waters Applications Note 720008117: Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Accordance With EPA 1633 Part 1: Establishing and Assessing the Method | Waters

Waters Applications Note 720008269: The Application of Cyclic Ion Mobility to Non-targeted Analysis of Per- and Polyfluoroalkyl substances (PFAS) in Environmental Samples | Waters

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