[en] It is investigated if a magnetic monopole, passing close to a sufficiently high-Z atom, may ionize it and originate a supercritical vacuum, this being followed by a spontaneous emission of a positron during the vacuum decay. Despite the lack of knowledge of the monopole structure, the relativistic equations describing the system monopole plus atom are solved by resorting to the numerical results already obtained in ion-ion collisions by Greiner and collaborators. It is found that the process of e⁺e^- formation occurs for the atomic numbers Z greater than 74