The quest for speed on snow is leaving a toxic trail. Switzerland – November 2025
Despite a global ban in professional competitions, Swiss ski slopes are still contaminated with dangerous “forever chemicals” called PFAS, according to new research from the country’s Empa, or Federal Laboratories for Materials Science and Technology. The source of the contamination is mainly recreational skiers using older wax products that contain these persistent pollutants, raising serious environmental and public health concerns in the pristine Alpine region.
The Discovery
Scientists from Empa’s Analytical Center have now made a corresponding discovery in the course of a sampling study during the Engadin Ski Marathon in March 2025. The snow samples taken at the starting line, two kilometers further down the track and in a background control area were clearly contaminated with per- and polyfluoroalkyl substances, synthetic chemicals that can take hundreds of years to degrade.
Markus Zennegg, head of Empa’s Analytical Center said the measurements were relatively high for certain types of PFAS that can come from ski wax, especially for perfluorinated carboxylic acids with an even number of carbon atoms in the chain of 6 to 14 carbon atoms. Maximum values are found at the starting point of the race course – hence where the skiers have freshly waxed skis – and contamination levels remained measurably elevated two kilometers into the course.
Environmental Concerns
The location of contamination is particularly worrying, with researcher Stefan Reimann pointing out that the measurable contamination was directly above Lake Sils. During spring snowmelt, such forever chemicals enter the water and can bioaccumulate in aquatic organisms and fish.
Subsequent soil sampling from the same locations showed continued, significant contamination with the persistent chemicals. At such concentrations, there is already a risk that PFAS will accumulate in excess of the permissible limits in the meat of cattle grazing in these alpine pastures during the warmer months, warned Zennegg.
The Source: Recreational Skiers, Not Professionals
The sports world has already reacted to the PFAS danger. The FIS has imposed a worldwide ban on all fluorinated ski wax in its competitions since the 2023/2024 season, including major events in Switzerland such as the Engadin Ski Marathon. So far, manufacturers have widely adhered to the new rules, changing their product lines to fluorine-free waxes.
The Empa team verified that this ban is effective among elite competitors: on the skis of the ten fastest professional skiers participating in the Engadin Ski Marathon, no PFAS could be detected. As Reimann said, “Obviously, you can be fast even without fluorine.”
However, the contamination found by Empa indicates that the long-term pollution is from the population of recreational skiers rather than from competitive athletes. The researchers say the cause of pollution most likely exists in a general lack of awareness among amateur cross-country skiers. This inference is also afforded full support by the fact that elevated PFAS concentrations were observed not just in the marathon tracks but also in area uses for normal cross-country trails.
The Problem with Old Wax
The fluorinated substances in ski wax are specially devised to enhance the gliding properties of the skis, thus helping ambitious cross-country skiers to go faster by reducing friction between the ski base and snow surface. Yet, modern fluorine-free waxes offer almost the same performance benefits but with minimal environmental impact.
Zennegg underlined that one block of wax may last for several years, and nearly all the ski wax used by older skiers contains PFAS. He recommended the exchange of old ski waxes with new ones free of fluorine, which is commercially available and labeled as such. “It simply makes no sense to release such stable substances into the environment for the few minutes’ advantage in a race.”
The mechanism of contamination is straightforward: as skiers glide across the snow, the fluorinated wax coating gradually abrades from the ski base, depositing PFAS chemicals directly onto the snow. This process is most intense at the beginning of a run when skis are freshly waxed, but continues throughout the skiing activity.
What are PFAS, and why are they dangerous?
PFAS are a class of thousands of synthetic chemicals prized for their water and grease resistance. They have been used in everything from waterproof clothing to food packaging since the 1950s, but their environmental and health impacts have become increasingly concerning.
These chemicals are also known as “forever” chemicals because they do not break down naturally in the environment. Super-strong carbon-fluorine bonds make them very stable and capable of surviving for centuries in soil, water, and living things. Once inside the human body, it may take a number of years or even decades to eliminate certain PFAS; some studies suggest that just one dose of certain PFAS compounds could take three to seven years to reduce by half in the body.
Many PFAS are known to be toxic to human health and the environment, linked to a variety of cancers, developmental and reproductive problems, hormone disruption, diabetes, obesity, and immune system dysfunction. They tend to accumulate in the food chain, possibly affecting everything from aquatic organisms and livestock up to humans.
Regulatory Response and Industry Action
This is not the first time PFAS contamination via ski wax has been found. For instance, research as far back as 2010 found high levels of various PFAS both in ski wax and in the blood of professional ski-waxing technicians. What is especially important about the Empa study is how it clearly demonstrates the way in which these chemicals move from recreational equipment into pristine natural settings.
The first real step forward, though, is the ban on fluorinated waxes instituted by the International Ski Federation for the 2023-2024 season. The ban applies to all FIS-sanctioned competitions worldwide and has been adopted by national ski organizations including U.S. Ski & Snowboard and the Canadian Ski Association. Violations result in disqualification from competition.
Ski wax manufacturers responded with a collective investment of millions of dollars to develop PFAS-free alternatives. Major brands such as Swix and Toko have fully phased out PFAS from their product lines, showcasing that safe alternatives are available and effective. In 2020, the U.S. Environmental Protection Agency fined Swix roughly $375,000 for importing ski wax products containing PFAS chemicals in violation of the Toxic Substances Control Act. The settlement resulted in a $1 million public education campaign called the Responsible Waxing Project.
Urgent Call for Consumer Action
The Empa researchers urgently advise the skiing public to take immediate action and accelerate the clean transition in order to preserve the unique alpine environment of Switzerland. Specific recommendations include:
- Immediately replacing any old ski wax products with clearly labeled fluorine-free alternatives
- Checking product labels carefully when purchasing new ski wax
- Proper disposal of old PFAS-containing waxes, not via regular household waste
- Spreading awareness among fellow recreational skiers about the environmental impact of fluorinated waxes
Ongoing Research
In the last few months alone, scientists in the Empa Analytical Center have established analytical capabilities for determining about 30 of the most prevalent PFAS in both different material and environmental samples, such as those from recycling processes. Further research is planned on PFAS to achieve a better understanding of the overall contamination of Swiss skiing areas and to monitor whether the switch to fluorine-free alternatives will actually reduce the levels of environmental contamination.
The Swiss research adds to the growing number of scientific evidence on contamination from ski wax with PFAS worldwide. Similar investigations performed in Austria, the United States, and other places have resulted in similar patterns of contamination, indicating a global problem that affects winter sports areas around the world.
A Model for Other Industries
While the focus of this research was ski wax, the success of the skiing industry in making that transition away from PFAS offers some important lessons for other sectors. Scientific research, regulatory action, industry investment in alternatives, and consumer awareness have combined to create a pathway for eliminating unnecessary PFAS use-a model that could be applied to countless other consumer products and industrial applications where PFAS are used today but not strictly needed.
But because these chemicals persist, even immediate action will not eliminate PFAS from Swiss alpine environments for generations. Contamination of soil and water systems will continue to pose risks long after the last fluorinated ski wax is discarded, a fact that makes prevention of further PFAS releases to the environment particularly important.
The message is clear for Switzerland’s skiing community: the time to go fluorine-free in ski wax is now. Every recreational skier switching to this alternative means protection for the pristine Alpine environment that makes Swiss winter sports possible—and safeguards the health of ecosystems, wildlife, and future generations.
Rerfence: Forever chemicals on the ski trail