Determination of Natural Uranium and Thorium Levels in Environmental Matrices Surrounding Uranium Mining Sites via ICP-MS. SciELO Preprints, 2025. DOI: 10.1590/SciELOPreprints.13524. Disponível em: https://preprints.scielo.org/index.php/scielo/preprint/view/13524. Acesso em: 14 maio. 2026.