How long does it take for aluminum foil to biodegrade?

Answer 1

Aluminum foil does not biodegrade. Biodegradation only happens when microorganisms (microbes, fungi etc.) use a material as food.

Aluminum foil can chemically degrade if exposed to acids or alkalis in soil or groundwater. It can be converted to aluminum oxide in a fire. It can be shredded into very small particles by abrasion, the smaller particles are more apt to be oxidized or dissolved.

If not exposed to this physical degradation aluminum will last for thousands of years