Two South Korean cross-country skiers were disqualified from ​the women’s classic sprint at the Winter Olympics on Tuesday after their skis tested positive for a banned substance, the International Ski and Snowboard Federation said.

Han Dasom and Lee Eui-jin were disqualified from the ‍qualification round after their skis tested positive for fluorinated wax, or fluor, a substance banned in 2023 due to ​its harmful effects on the environment and human health.

The Korea Ski Association did ‍not immediately respond to a request for comment.

Fluorinated ‍wax was originally used in sailboats to help with ‌glide ​and came to skiing, a sport where ‍glide is also crucial, in the late 1980s, according to the FIS.

The substance ‌does not biodegrade, making it a so-called “forever chemical” and it can pose a health risk to ski technicians who would apply the wax ‍with a hot iron in poorly ventilated areas.

FIS announced a ‍ban on fluor in 2019, which took full effect in the 2023/2024 season. Skis are checked in a test area, ​often near ​the ‍finish line.

Han and Lee, ranked 157 and 158 in the World Cup respectively, were not expected to be ⁠in the running for medals in Tuesday’s race. (Reuters)

Norway's Johannes Hoesflot Klaebo (center) celebrates as crosses the finish line during the men's cross country 10km + 10km skiathlon event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on Sunday. (AFP via Yonhap)
Norway's Johannes Hoesflot Klaebo (center) celebrates as crosses the finish line during the men's cross country 10km + 10km skiathlon event of the Milano Cortina 2026 Winter Olympic Games at Tesero Cross-Country Skiing Stadium in Lago di Tesero (Val di Fiemme), on Sunday. (AFP via Yonhap)