The Steramine is not toxic. It's actually used heavily in food service industries for that reason. I'm aware of it as it's one of the main products sold to sanitize your rebreather loop. The breathing hoses and counter lungs of a CCR is sort of like a tuba. Full of moisture and spit and a prime medium for growing funky bugs. A steramine spray or dip will kill most virus and bacteria, but you eat from it and breath through it.