ABSTRACT
Aluminium and silicon can enter the aquatic environment by leaching from the aluminosilicates of rocks and soil minerals. Aluminium can exert toxic effects whereas silicon is claimed as an essential element. After oxygen, the two most abundant elements in the earth's crust are silicon and aluminium combined as the aluminosilicates of rocks and soil minerals. The incidence of serious disorders in patients on long-term dialysis showed a geographic distribution related to the concentration of aluminium in the water used. The rate of binding of Fe3+ was increased when silicic acid was present, so that citrate and silicate co-operate in presenting iron to desferoxamine by retarding polymerisation. This chapter addresses the issue of the role of silicon in determining the bio-availability of aluminium, a hitherto neglected consideration. The nature of the interaction of aluminium and silicon in aqueous solution may be of general importance in biology.
