The purpose of this work is to evaluate the environmental hazard of mineral exploration and mining on the Moon by means of the trace elemental analysis of lunar regoliths and impact assessment of trace elements on the health of future lunar colonists. Currently, in space research, the problem of using near-Earth space and introducing mineral mining technologies is becoming especially relevant. To meet this objective, this work uses the modern computer technology for classifying multidimensional observations (G-method), which makes it possible to distinguish homogeneous taxonomic units (types, classes, etc.) under conditions of self-organization without an instructor. To assess the chemical composition of regoliths, the concentration coefficient and the total quality reduction index were calculated. According to the resultant classification of 38 trace elements, 13 most aggressive elements are distinguished; the concentrations of these elements in regoliths are many times higher than their concentrations in terrestrial soils: Cr, Ni, Be, Co, Sc, Au, Y, Gd, Tb, Dy, Ho, Er and Lu. It is these trace elements that can have a negative impact on the vital activity of selenauts. The classification of regoliths and basalts of all lunar expeditions (19 lunar samples) showed a wide variety of their chemical composition and pointed at the need to assess its quality. According to the chemical composition, all regoliths are classified as ‘crisis’, and only regolith Apollo-14 can be classified as ‘disaster’. Furthermore, the toxic effect of the aggressive trace elements on bodies of future lunar colonists is characterized and the most likely diseases are given. Thus, the level of the environmental hazard during the Moon exploration due to the trace elements of regoliths is evaluated, and the need to continue the research is stated.