The toxic effect of a metal/carbon copper nanocomposite (Me/C Cu NC) on higher plant seeds and the bacterial sensor “Ecolum-8” was evaluated. A significant inhibitory effect of 0.1% nanomaterial on the seedlings of radish seeds was established. Some stimulating effect on the development of the roots of this culture was found at a concen-tration of 1 • 10–8%, but it was insignificant (by 11.3%).