Perchlorate

This stuff is a very strong oxidizer with its own particular hazards. It can be pretty rough. Usually.

Even requires a special dedicated fume hood to handle perchloric acid under, made of stainless and/or PVC as well as the ductwork and blower fan:

https://www.escolifesciences.com/products/ducted-fume-hood/f...

https://www.labconco.com/product/protector-pvc-perchloric-ac...