The medicinal and dermo-cosmetic uses of clays date back to prehistory. Clays mixed with water and different types of mud were used by early humans for healing wounds and skin cleansing. Clays are naturally occurring ingredients in many natural health products, mentioned in many ancient Mediterranean and European medical texts, and currently used to prepare therapeutic hot-mud (peloid) baths at numerous spas in Mediterranean regions. We acquired eleven samples in five Tunisian town markets of green and brown clays traditionally used to prepare homemade mud-packs intended for topical application. These clays were partially characterized in a previous study regarding their mineralogical, chemical, textural and thermal properties. This study aims to evaluate the feasibility of these green and brown clay samples. We present data of pH, zeta potential and in vitro cation release from these inorganic gels. Other properties such as rheology and particle size distribution are also considered to be relevant given the clays' topical administration as cosmetic products.

This research was supported by funding from the Spanish Group CTS-946 and projects CGL2016-80833-R, IRSES MEDYNA (PIRSES-GA-2013-612572) and PTQ-15-07625.