Geophagic clays in Lubumbashi, DR Congo

Geophagy, a form of pica, is the consumption of clay soil, particularly prevalent among pregnant women in Lubumbashi. A study of 450 women revealed a prevalence of 68%, with the majority consuming kaolin (81%) from various regions.Organoleptic analysis highlighted distinctive characteristics of the soils consumed, while physical and chemical tests revealed the presence of chemical elements such as SiO¿, Al¿O¿, Fe¿O¿, TiO¿ and K¿O, as well as heavy metals (As, Cd, Pb, Ni) and uranium-bearing substances. The cation exchange capacity ranged from 21.4 to 31.0 meq/100 g, and the soils were acidic according to their pH.This study highlights the prevalence of geophagy in Lubumbashi, regardless of social conditions. It opens up prospects for the development of decontamination methods so that these clays can be used in pharmaceuticals without posing a health risk.