Element mobility in clays for healing use.

Hereby, it is considered the literature concerning the mobility of chemical elements from healing clays to the human body, including in vitro and in vivo studies with specific aim. Two main types of clay administration for healing uses are topical applications (usually in spa centres) and ingestion (either in a voluntary or unintentional way). The mechanism of element mobility is very different for the two applications. The topical use mainly involve soluble and exchangeable chemical elements, whereas the ingestion of clays is more effective due to great aggressive conditions into the stomach. Some poorly known implications of clay uses are mentioned, such as the effects of organic compounds in the transdermal migration of elements and the effective simulation of the digestion, that is in balance between chemical leaching and adsorptive effect of clays.