Excess aluminum has been linked to neurological disorders. What a surprise. Aluminum is the most abundant metal on earth making up one-seventh of the earth's crust. Now I'm reading that the leaching aluminum can cause health problems.
Soybeans are a legume, are in the pea family, and as such are naturally high in aluminum.
Organometallic aluminum, not synthetic aluminum or a chemical aluminum compound. Not the aluminum that cookware or airplanes are manufactured from. In talking with chemist Tom donVito of SUN Chemical, I learned that clay, another source of naturally occurring aluminum, is also a component of soy-based ink. If you garden in clay, you garden where aluminum silicate naturally occurs. All soils save sand contain clay.