The toxicity of smoke-generating ammunition can be established by looking at the complete hand grenade or only at the smoke composition. In this paper both approaches are described. The toxicity of a signalling smoke was assessed as a complete smoke hand grenade whereas for a 76mm screening smoke canister only a red phosphorus (RP) pellet was studied. For both smokes the particle size distribution and the toxic effect of the smoke on A549 lung cells in culture in an Air-Liquid Interface (ALI) system were determined. The assessment of the complete smoke hand grenades also included the determination of the mutagenicity using an Ames test. RP pellets are destined to be burnt on the surface and for this reason the influence of small sand particles on the acute toxicity was also investigated. For both types of smoke the majority of the formed particles were smaller than 2.1m, which means that they are capable to penetrate deep into the airways after inhalation. The complete hand grenade approach showed that smoke grenade design can have influence on the final toxicity and mutagenicity of the formed smoke. Sand upon which an RP pellet is burnt can function as a carrier material resulting in an indirect exposure.