A training aid for use in training canines to detect an explosive material includes an explosive material adsorbed in the pores of a high surface area mesoporous or nanoporous host material. By adjusting the surfaces of the pores of the substrate material, the substrate can accommodate various types of explosive materials in a non-detonable and non-flammable manner, including nitroaromatics, nitroamines, nitrate-based explosives, and peroxide-based explosives. When the training aid is in an unsealed condition, a continuous flux of explosive material is released without providing any explosive or flame hazard to the trainer and canine.