Chemical engineers in Portugal have come up with a solution to the smelly socks problem. A new type of "microcapsule" filled with perfume can be embedded in fabric for producing scented suits, socks, underwear and other clothing.

Alirio Rodrigues and colleagues at Porto University point out in the journal Industrial & Engineering Chemistry Research that microcapsules, or microscopic shells, have been used to deliver fragrances in products such as scratch-and-sniff stickers. But these microcapsules are made with formaldehyde, which is toxic.