I'm almost POSITIVE that 20 Mule Team Borax is on our 'safe list'!
It's used internally to detox from fluoride...and I personally know a gal that had extreme chronic fatigue and put 1/8 teaspoon of it in a liter of water every day for 2-3 weeks, and had amazing results.
And of course, using an isolated chemical internally is not without it's concerns (but virtually ANYTHING is better than fluoride poisoning). It seems to me to very safe for cleaning purposes.