The invention relates to an insecticidal water-in-oil (W/O) formulation with at least one insecticidal active substance and at least one burning salt and to the preparation of this formulation. The formulation according to the invention is particularly suitable for the treatment of suitable supports, in particular of paper supports, in an economical one-step process with the aid of conventional application processes. In addition, the present invention relates to insecticidal, smoulderable products which are prepared by treating a support with the formulation according to the invention.
