The change in the microelement content of aqueous media affects the development and the vital process of microorganisms. The
present paper treats the accumulation and the influence of the toxic elements Cd and Cu on the metabolic processes proceeding
in bacterial communities. To trace the dynamics of one of the basic metabolic processes, oxygen consumption was measured polarographically.
For tracing the accumulation of the additionally included Cd and Cu in the experimental volume of water, the nondestructive
method of neutron activation analysis was used. The results show a correspondence between the inclusion of elements and the
change in the breathing as a function of the additionally included concentration of the investigated microelements. The more
toxic effect of Cd on the oxygen consumption is noticeable.