I sprayed on my first dose, started coughing from the mist, then looked up the material safety data sheet on propylene glycol out of curiosity. The LD50, 20g/kg both oral and on skin, looks like nothing to worry about. But it says to use self-contained breathing apparatus in the event of a spill or discharge. Should I worry? I'll definitely track down all the ingredients and make a gel for my next cycle, now that I know where to get them, but for this one is there anything to worry about?