Nontoxic must have two meanings…
This boingboing post refers to two compounds as “powerful yet nontoxic” and “safe.” Luckily the commenters are smarter and note the fact that sodium hydroxide, conveniently labeled as NaOH for those who passed high school chemisty, is LYE. Ugh. Not recommended.
Knowledge is not a dangerous thing. Stupidity is dangerous. Thinking you have knowledge is more dangerous. Wisdom is knowing where your personal line between knowing and just thinking you know lies. (Yes, that’s a lawyerly skill — well-trained lawyers are typically very good at helping you discover that line during their questioning.)