Climbing gyms may be teeming with toxic rubber particles, recent research shows. The study found high levels of rubber additives in the air and dust of two climbing gyms, likely coming from the soles of special climbing shoes worn by gym-goers. The authors say that customers and employees at climbing gyms may be exposed to more of these particles than elsewhere in their daily lives.
The research was led by scientists from the University of Vienna, some of whom had previously worked educated how rubber and its additives that improve properties can end up in the environment.
While much of this pollution comes from tires and roads, the authors noted that many sports equipment also contains a lot of rubber. Climbing shoes in particular have additives that make the rubber particularly flexible and sticky, and the soles are designed so that they wear slowly as you climb, creating the friction that is important for grip. The end result is that these shoes produce a lot of rubber particles that end up on the steps while climbing. And the constant sweeping away of these particles by climbers ensures that they regularly end up in the air, waiting to be inhaled, the scientists hypothesize.
Previous research has already proposed that climbing gyms can contain a lot of indoor dust and potential pollution, although some have argued that much of this comes from the chalk that climbers use. This time, researchers decided to specifically look for 15 known rubber compounds in the air and dust of two climbing gyms and collect samples during peak business hours.
As has been found in other studies, researchers also found high levels of overall dust in the gyms. They also discovered nine of the 15 rubber-derived compounds in the air and 12 of these compounds in dust. To confirm their suspicions, they found high concentrations of the same compounds in climbing shoe samples, with one sample containing all 15. These compounds were also found in the powder collected from the top of the climbs, further supporting their hypothesis. And based on their estimates and other data, climbers and staff at these gyms likely have more daily exposure to these additives than anywhere else.
“These results identify a previously unknown route of human exposure to rubber additives and highlight the global problem of toxicity from plastic additives,” said the authors wrote in their article, which was published as a preprint article on ChemRxiv in early February.
The team’s work has not yet been subjected to the typical peer review process, so the conclusions should be viewed with some caution for now. The exact health effects of these compounds on humans are also still unclear, although certain ones, such as: 6PPD-quinone They are known to be toxic to fish, while other studies support this found that tire rubber particles in general can be harmful to the health of our respiratory system.
At the very least, researchers say more should be done to curb the potential threat of air pollution in these gyms. And much like tire manufacturers have begun to do, the team argues that climbing shoe manufacturers should be forced to remove and replace rubber compounds from their products that are most likely harmful to human health.
“Until rubber becomes safer, possible strategies to minimize exposure in climbing gyms should also be considered, such as more frequent cleaning, mobile and stationary HEPA air filters, or a ban on certain shoe models,” they added.