Black substance on outlets

I just inspected a 4 y.o. house and found some black staining on 3 outlets. They were in different rooms and not all on outside walls. The staining is like a fine powder which wipes off easily. Any thoughts?

Probably from those plug in air fresheners…

That happens often here in Colorado, the Power Company sends out a high test signal, and here we have the black carbon dust electrical backflow preventers, it they aren’t working then the black carbon dust spills out onto the outlets and they know they need to replace those black carbon electrical backflow preventors on that part of the grid.
I may be wrong though, Ask Mark or Paul, they are the Guru’s,

That’s a new one :-k

Paul’s the Guru. I just twist wires together.

This was just discussed a few days ago anyhow.

Thanks Marc. Just went over there and looked at it. Must have missed it earlier.

I believe it is DUST from air probably around the openings and possibly back drafting…I would suspect Glades Plugs…or something similar in the outlets.

Other than that…if it was from arcing you would be able to smell it and get the smell of charing…or burning from the plastic…the fact it wipes off tells me I don’t believe it has anything to do with arcing…but thats just my OP.