Aluminium is the worlds most common metallic element. It constitutes about 8% of the Earth's crust. It occurs in various chemical forms (species) in most rocks and soils, in vegetation and is found in most water supplies and as part of dust particles in the air. Aluminium  is also present in all clays, making it an constituent of cooking vessels since earliest civilization. Evolution of human life and civilisation has developed in an aluminium rich environment.
While aluminium is abundant in the environment, the naturally occurring forms are usually stable and do not interact with the biological processes which go on in living organisms. Under acidic conditions, however, aluminium may be released from rocks and soils in a soluble form which can be absorbed by plants and animals.