A pair of shoes has gone viral on social media after images showed their soles completely crumbling while being worn, leaving behind powder-like debris on the floor.
In the photos shared online, the footwear appeared to have severely deteriorated, with the outsole breaking apart into small fragments as the wearer walked.
According to the owner, the shoes had been stored in a box for five years before being worn for a special occasion. However, they reportedly began falling apart while the person was on the way to work.
While the incident may appear unusual, experts say it is actually linked to a chemical process known as hydrolysis.
Industry sources, including Safety Jogger, explain that many modern shoes use polyurethane (PU) in their soles due to its lightweight, flexible and shock-absorbing properties.
However, PU is also susceptible to ageing through hydrolysis, a chemical reaction where moisture — particularly water vapour — gradually breaks down the material’s molecular structure over time.
This process can occur slowly over several years even if the shoes are not actively used. The deterioration becomes more severe when footwear is stored in hot and humid environments, such as tropical climates or poorly ventilated spaces like closed cupboards or drawers.
In extreme cases, the sole loses its structural integrity completely, leading to cracking, crumbling and eventual disintegration into powder-like residue, as seen in the viral images.
