Toxicity Evaluation of Smoke Pyrotechnic Compositions Based on the Dimensional Analysis of Solid Combustion Products

The use of smoke pyrotechnic compositions bring during use an intoxication risk to the staff located in the immediate proximity. One of the methods for pyrotechnic composition toxicity evaluation consists in the dimensional analysis of the solid particles resulted from the combustion and the determination of the respiratory system intrusion rate. The experimental determinations were performed for three new smoke compositions: two of them based on potassium chlorate and potassium chloride and, respectively, ammonium chloride, the third composition being based on potassium nitrate and red phosphorus. The tests demonstrated that solid particles within the aerosols generated from the first two compositions present diameters between 0.1 and 1.0 μm. The deposition fractions of these particles in the respiratory system have significant values only at head airways level and alveolar region, therefore presenting low toxicity for the human body. In the case of the pyrotechnical composition based on red phosphorus, solid particles with medium diameters between 0.1 and 8.0 μm were generated, the deposition fractions having higher values than in the other compositions, therefore leading to a higher toxicity for the human body.