The present invention relates to the use of vanadium-containing particles as a biocide, in particular to the use of vanadium-containing particles comprising at least one vanadium compound and a support material or of a support material in which some metal atoms from the crystal lattice have been replaced by vanadium. Furthermore, it relates to method for preventing biofouling of a substrate and to a method of imparting biocidal properties to the surface of a substrate.
