AIO liquid cooling toxicity and pets -- worry or not?

I'm planning to get ARCTIC Liquid Freezer II 360 for my new build, and the computer will be a room where my cats live in 24 hours/day.

I just started to wonder what's the worst case if the liquid leaks. Through some search I figured that ethylene glycol is not a big problem if people accidentally drink it, but a small amount may cause problems for cats and dogs.

I know that good AIO brands have a very small chance to get broken, and even if it's broken it doesn't necessarily leak out of the computer case. However I just wonder if I should switch to air cooling to err on the very safe side.

On the other hand, I'm wondering if I'm way overthinking this. I don't see people discussing this on the internet at all, including custom liquid cooling, which has a bigger chance to leak. Any insight?