Members of one of the National Societies which are the official participants "Associazione Italiana per lo Studio degli Elementi in Traccia negli Organismi Viventi (A.I.S.E.T.O.V.)"; the "Gesellschaft für Mineralstoffe und Spurenelemente (GMS, the "Société Francophone d'Etude et de Recherche sur les Eléments Trace Essentiels (SFERETE)", the "Russian Society of Trace Elements in Medicine(RUSTEM)" and the Spanish society: "C. Elementos Traza de la Sociedad Española de Química (CETSEQ)" are simultaneously members of the FESTEM.

Any national society on Trace Elements and Minerals can ask to the General Secretary to become official member of the FESTEM. It is a requisite that the national society has been officially legalized in the country.

Individuals working on Trace Elements and Minerals in any country are invited to become member of one of the national societies: "Associazione Italiana per lo Studio degli Elementi in Traccia negli Organismi Viventi (A.I.S.E.T.O.V.)"; the "Gesellschaft für Mineralstoffe und Spurenelemente (GMS, , the "Société Francophone d'Etude et de Recherche sur les Eléments Trace Essentiels (SFERETE)" , the "Russian Society of Trace Elements in Medicine(RUSTEM) and the Spanish society: "C. Elementos Traza de la Sociedad Española de Química (CETSEQ)".