*lol* only one - and she spat it out pretty sharpish
we followed up with bubble painting yesterday and sent 3 home with blue tongues... made the co-teacher panic a bit *oops* but the kids themselves were unfazed.
I imagine you'd have to drink a fair amount of bubblebath before it did you any harm but if we wanted to be hyper-safe then we could have used 'baby' formulations. I demonstrated with the only one that could have been potentially dangerous to a toddler (some pretty virulent-coloured bath salts) because I couldn't read the packaging (everything else was things that I had brought from the UK but they were bought here).