Temperatures are dropping, snow is falling and skiers are waxing their skis for another season gliding down Colorado’s iconic mountains.

Those waxes, however, may be toxic.

Some ski waxes contain per- and polyfluoroalkyl substances, or PFAS — a label for thousands of types of manufactured chemicals that do not break down in the environment. As that toxic wax glides along the snow, it slowly flakes off. As the snow melts into water, it carries the tiny deposits down into Colorado’s water supplies.

Humans who are exposed to PFAS, also known as “forever chemicals,” are at risk when the substances build up in the body. They can cause decreased fertility, increased risk of some cancers and suppressed immunity.

The U.S. Environmental Protection Agency has focused more intently on ski waxes in recent years, though little has happened on the state or local levels to address the toxic waxes in Colorado — home to 28 downhill ski resorts, and even more nordic centers, that millions of skiers visit every year.

“This is a classic micropollution problem. On an individual basis, it’s small,” said Peter Arlein, founder of a Carbondale-based company called mountainFLOW that sells non-toxic, plant-based ski waxes. ”This is invisible, but it adds up.”

Many industries use PFAS to keep things from sticking. Chemicals are applied to cooking pans to create a non-stick surface, to furniture to help them resist stains, and to skis so that they glide easier and faster across snow.

The EPA has banned the production or importation of new flouro ski waxes, but already existing fluorinated waxes can still be sold and purchased. Fluorinated ski waxes often are expensive and are generally reserved for ski racing.

In 2020, ski wax company Swix Sports settled alleged violations for importing ski waxes with PFAS that violated the Toxic Substances Control Act. In 2021, a different company, TASR, settled alleged violations for also importing ski waxes with PFAS.

“Review of the risks from PFAS in ski waxes is particularly important,” the EPA said in an alert, given the potential exposure for ski wax technicians and skiers who apply their own wax. “Additionally, PFAS may enter the environment from the use of waxed skis and from the ski wax shavings scraped off during application.”

Colorado lawmakers in 2022 banned the sale of an array of products to which PFAS were added — including rugs, food packaging and cosmetics — but did not address ski waxes.

The Colorado Department of Public Health and Environment has not investigated how PFAS from ski wax might be affecting the state’s water. But a department spokeswoman said the agency was aware that some waxes contain forever chemicals.

“The Water Quality Control Division has been laser-focused on monitoring for and mitigating PFAS in drinking water because we know when drinking water is contaminated with PFAS, it could be a significant source of exposure,” spokeswoman Kaitlyn Beekman said in an email. “If any communities have concerns about the presence of PFAS in their drinking water, the division has resources, including grants, to help them with further testing to identify any potential contamination.”

No bans in Colorado

While neither local governments nor resorts in Colorado’s ski country have banned the use of fluoro waxes, at least one Rocky Mountain ski town has outlawed the products.

Park City, Utah, in March banned the use or sale of fluorinated ski wax after connecting PFAS in its water supply to a cross-country ski area that is directly above an aquifer, said Michelle De Haan, the city’s water quality and treatment manager. Further testing in the spring matched the chemicals found in the water with those tested at the cross-country race start line, as well as near the lifts at the resort.

“This is impacting our drinking water and our environment broadly,” she said. “It doesn’t go away. We don’t want the concentration to get worse or for it to hit another water source.”

Enforcing the ban is difficult, De Haan said. The city has focused its efforts on public education. Officials have encouraged people and ski shops to turn in any fluorinated ski wax sitting on shelves.

Since last winter, they’ve collected more than 600 pounds of wax, which must be incinerated by a contracted company.

“Being a small town, the community has responded well,” she said.

The ski competition community has begun to ban fluorocarbon waxes, though enforcement has proved tricky there, too. The International Ski and Snowboard Federation multiple times has postponed the implementation of a ban on the substance because testing whether athletes are using banned waxes is slow and expensive.

The federation, which oversees the highest level of alpine sport competition, finally banned flouro waxes for the 2023-24 season. It will randomly test for the substance.

In Colorado, Summit County officials are aware of Park City’s initiative but have no plan to follow suit, said Sarah Wilkinson, a county spokeswoman. The county will test for PFAS when there is a concern, she said.

But there have been voluntary changes.

Arapahoe Basin years ago swapped to a biodegradable ski wax, Purl, and recently added mountainFLOW wax to its shop, said Mike Nathan, the sustainability manager at the ski area. Arapahoe Basin will start a takeback program this winter in which people can drop off any fluoro wax they have and receive a free wax from the shop.

“It might be tough for us to ban it or know what people have on the bottom of their skis and snowboard,” Nathan said. “We’ll certainly be hoping to motivate people.”

Alternative wax options

As the ski world moves away from fluorinated waxes, companies are producing waxes that are better for the environment.

In 2019, Carbondale-based mountainFLOW began selling plant-based, flouro-free ski wax. Arlein, the founder, worked in the ski industry for more than 20 years, including years spent waxing skis in a shop’s small back room.

“The more I learned about it, the more I became passionate about something that was better for the planet,” he said.

People who have applied fluorinated waxes to skis, a process that includes melting the wax and releasing vapors, are most at risk of experiencing harmful health effects. The chemicals can build up in their bodies, increasing the risk for cardiovascular disease, liver damage, cancer and hormonal problems. Studies conducted in Norway and Sweden found that wax technicians working for World Cup ski teams had blood levels of some chemicals that were up to 45 times higher than the general population.

But as the industry shifts, Arlein has concerns about the waxes that will replace fluoro versions. Most are still petroleum-based products, he said, which carry their own ecological impacts.

“For the most part, we don’t know what’s in the wax, and we don’t know what they’re using instead of flouro — it could be good or it could be worse,” he said.

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