The IBeA group of the EHU-University of the Basque Country is proposing new measures to safeguard the purity of extraterrestrial samples. Several contaminants, including traces of ink, originating in the preparation of subsamples, have been identified in Martian meteorites by the EHU's research group. The finding highlights the importance of stricter protocols to prevent misinterpretations of the composition of these rocks and to ensure the reliability of future studies and Mars sample-return missions. The research is published in the journal Applied Geochemistry.