biggest science pet peeve:

people who think that listing all of the possible uses of a chemical constitutes a real argument against its safety.

Like I have news for you: chemicals have multiple different properties! Water, in addition to being very necessary for us to survive, is also really useful as a lubricant and flame retardant. But basically no one looks at a glass of water and thinks “gee that may not be safe isn’t that the same stuff that the sprinklers would spray out if my apartment caught fire?”

Also, the constituent parts of any given chemical have absolutely no effect on its toxicity. To use the cliche example table salt is made of equal parts chemical weapon and explosive.

And that’s leaving alone the biological interactions. We all need liquid water to live but very few of us would enjoy having it in our lungs. Toxicity depends on the way that something is taken! You should get this intuitively- put some shampoo on your skin to put it in your hair, you’re fine. Get it in your eye? That hurts but probably won’t leave any long term damage. Did you drink half the bottle? Call an ambulance.

And this even isn’t getting into minor things like the fact that our bodies produce lots of toxic shit that we get rid of regularly and that we have lots of fairly sophisticated mechanisms to not die from small amounts of, say, formaldehyde. There is a dose-response effect to all of this shit- below a certain dose you’ll have no ill effects, and above a certain dose you’re all but dead. That goes for everything from sugar to cyanide.

tl;dr chemistry and biology are complicated, stop drawing conclusions about the safety of things from context-free lists of random properties it has