For future reference:
So I had a spray bottle of the stain remover that I use for ring around the collar pre-treating. There was so little left in the bottle that it wouldn't spray. Being a fucking moron, I added a scoop of the regular Oxy powder and filled it up with water. Shook it up to dissolve, then sprayed my clothes. Set the bottle back on the shelf and went about my business.
About 5 hrs later, close to midnight, there is a massive BANG. It sounded like something fell in the attic. We checked every room in the house except the laundry room, and couldn't find anything. The next evening I checked the laundry.
Plastic shards everywhere. White spots over ALL surfaces: walls, floors, ceiling, every rag, every bottle, the washer dryer. The entire room is covered in plastic shards and white residue.