Dirk Puslich wrote:

Hello,

I just moved into an old house (build in the 1920s) with a finished
basement (finished about 10 years ago).

About a month ago we noticed a sickly sweet smell around the back
wall. It doesn't smell musty, but it is quite strange and we don't
like it. It seems to almost go away and then come back stronger
sometimes.

The former owner had some mouse poison out so my theory is that one or
more mice might have died in the wall and are causing the funk.

My problem is that I don't know what a dead mouse smells like, so I'm
not sure if that is it. It's hard to describe the smell but there is
definitely a "sweetness" to it, but not a "mmm someone's making pie"
kind of sweet, but one that is somehow unpleasant.


Maybe it is the mouse poison? Or an aromatic hydrocarbon based
insecticide, like Lindane?

Wait! I've got it! Thousands of Asian ladybugs or boxelder bugs inside
the wall.

As someone else already said, the smell you're describing is the
characteristic smell of bedbugs.

I'm glad it's your house and not mine,
Bob