Softstar Shoes
The strongest current US shoe candidate: natural leather with formaldehyde-free tanning language, non-toxic food-grade dyes, Oregon handcrafting and vegetable-tanned Ecopell options. Choose the simple leather and Ecopell models.
Still not pure. Soles, glues and rubber remain. Avoid the waterproof and heavily technical styles.
A US source in the The Second Skin directory. Check that it ships to Europe; where it does not, the directory lists a European alternative alongside it.