Not read the paper yet but figured this might be of interest to some so thought I'd link to it...
[The Invisible Footprint of Climbing Shoes: High Exposure to Rubber Additives in Indoor Facilities](https://pubs.acs.org/doi/10.1021/acsestair.5c00017)
News Article : [Chemicals released by climbing shoe abrasion could lead to lung issues for climbers in indoor environments](https://phys.org/news/2025-04-chemicals-climbing-abrasion-lung-issues.html)
Along with chalk and viruses... and friction! ... yet another good reason to have plenty of ventilation in indoor walls. And not just just for climbers, but also and especially for the staff.
