Ammonium chloride based smoke is irritating to the eyes and lungs as it contains some remaining HCl and NH3. Ammonium chloride itself is not poisonous and is even used in some type of candy. But as with all fine powders a dust mask must be worn, and since ammonium chloride is irritating to the skin and damaging to the eyes, gloves and goggles are important. Acording to Shimizu, ammonium chloride forms an exception to the rule that ammonium compounds should not be mixed with chlorates. Due to the lower solubility of potassium chlorate (compared to ammonium chlorate) no ammonium chlorate should form. I personally would still use these mixtures with great caution (or avoid them) since it seems inevitable that small amounts of ammonium chlorate will still form. The lower solubility of potassium chlorate will make it the -main- product in a double decomposition reaction but not the -only- product. It is strongly advised not to mix with metal powders, specifically copper, because it will become extremely corrosive. Toxicity: Oral rat LD50 : 1650 mg/kg Investigated as a mutagen.