Is chlorine dioxide safe and effective?
this to say about it. It would seems so, as long as it is in solution. The gas form is another matter, but we would not encounter that. However two special cases can cause problems. The first is chlorinated tap water, curiously enough. It seems that the extra chlorine in the water can react with the chlorite ions or the chlorine dioxide and liberate chlorine gas. This smells and is bad for your nose and mouth. Hint: it is no use testing Aquamira out on chlorinated tap water! The second case is water with a high level of sulphur in it. This is not all that common, but can happen. The sulphur can be oxidised to sulphur dioxide, which can form sulphuric acid. Testers have reported quite an acid burning sensation when this happens. However, I believe sulphur-laden water would normally smell rather badly, so you should be able to pick that case out. Few walkers in Australia would encounter this.
