Turns out that stuff that lets us glide effortlessly across frozen surfaces is not only toxic but can remain in the environment for many years. Researchers reporting in ACS’ Environmental Science & Technology have found that certain perfluoroalkyl substances (PFASs) found in ski wax bioaccumulate and biomagnify in the food chain at a Nordic skiing area.
PFASs in ski wax are used to enhance the glide on the film of water between skis and snow. Eurekalert.org reports there has been a recent uptick in concern about the persistence, bioaccumulation and potential toxicity of PFASs in the environment. Consequently, the U.S. and other countries have banned or limited use of the most worrisome forms, perfluorooctanoic acid (PFOA) and perfluorooctansulfonate (PFOS), but these stable compounds and other PFASs can remain in the environment for many years.
To explore the extent of this bioaccumulation Randi Grønnestad and colleagues examined the levels of various PFASs in soil, earthworms and bank voles (small rodent), at a the he Granåsen Ski Center in Trondheim, Norway.
The researchers collected soil and animal samples from the ski center and from a forested reference site untouched by skiers about 9 miles away. The team analyzed PFAS levels in soil and found that three individual PFASs were present at significantly higher levels at the ski area compared with the reference site.
In earthworms, only two compounds were found at significantly higher levels at the ski resort. In contrast, bank voles from Granåsen had 5.7 times higher total PFAS levels in their livers and significantly higher levels of several long-chained PFASs found in ski waxes, including PFOS, than those at the reference site. The detected levels of all PFASs were far below toxicity thresholds but the observed bioaccumulation in earthworms and biomagnification of PFOS from worms to voles suggested that the compounds could accumulate at much higher levels in top predators, the researchers say.
Perfluoroalkyl substances (PFASs) are used in a wide range of consumer products, including ski products, such as ski waxes. However, there is limited knowledge on the release of PFASs from such products into the environment and the resultant uptake in biota and transport in food webs. We investigated levels, patterns, and biomagnification of PFASs in soil, earthworms (Eisenia fetida), and Bank voles (Myodes glareolus) from a skiing area in Trondheim, Norway.
In general, there was higher PFAS levels in the skiing area compared to the reference area with no skiing activities. The skiing area was dominated by long-chained perfluorocarboxylic acids (PFCAs, ≥70%), while the reference area was dominated by short-chained PFCAs (>60%). The soil PFAS pattern in the skiing area was comparable to analyzed ski waxes, indicating that ski products are important sources of PFASs in the skiing area. A biomagnification factor (BMF) > 1 was detected for Bank volewhole/earthwormwhole for perfluorooctansulfonate in the skiing area. All other PFASs showed a BMF < 1.
However, it should be noted that these organisms represent the base of the terrestrial food web, and PFASs originating from ski wax may result to higher exposure in organisms at the top of the food chain.