Clean the insoles with vinegar. Using a mixture of 2 parts vinegar and 1 part hot water, soak the insoles for a few hours. Vinegar is a natural disinfectant and will work to kill the bacteria hiding in the shoes.
Huge amounts of iron are used to make steel, an alloy of iron and carbon. Steel typically contains between 0.3% and 1.5% carbon, depending on the desired characteristics. The addition of other elements can give steel other useful properties.
Most of the molten iron from a Blast Furnace is used to make one of a number of types of steel. There isn't just one substance called steel - they are a family of alloys of iron with carbon or various metals. More about this later . . . Steel-making: the basic oxygen process.