u/Interesting-You5404

Hello

I live in an apt that often hits 70+% humidity in summer unless a dehumidifier is used.
I will of course use a dehumidifier but I do not know if all of the previous tenements have done so.

That being said there are these marks on the ceiling and I am being increasingly concerned that they are mold and not soot.

I am just wondering if anyone would be able to help give me some more insight into this.

Thank you!

Edit: This is in the US. The marks were present on cieling upon moving in.