What is the best way to clean the foot pad of sandles?

I bought a pair of used Birkenstock sandles (online auction)and the foot area is black. Before I throw them away, I thought I would ask if anyone knows a good cleaning agent to use on these sandles.. The straps are leather, don't know what the foot pad is, but below it is cork and then rubber. These are expensive shoes, but I won't put my foot on them in this condition.

What is the best way to clean the foot pad of sandles?
You could try saddle soap and then dry them in the sun. That should kill germs too.
Reply:Use Birkenstock Footbed Cleaner (available only in the Birkenstock Deluxe Shoe Care Kit) to prolong the life of your footwear. This special formula penetrates the footbed to remove odors, dirt, oils, and perspiration. Please note: although we buy only the highest quality leather and test it for colorfastness, dyed leathers will sometimes shed their color. Please be very careful with delicate or light colored socks, especially when your footwear is new! You can also use Birkenstock Leather Protector to minimize dark leather footbed liners from shedding their color.
Reply:Febreeze and a stiff wire brush. Worked for me!