Has this ever happened to you?
 

I visited my parents over the weekend, and when I got back to my apartment it smelled like something had died in the kitchen.

I discovered that the bottom side of a floormat placed in front of the fridge was all wet, and the stagnant moist rubber smelled like piss. I know I did not piss on it, and there are no animals living here.

No leaks coming from the fridge, not to mention that the top surface of the mat was perfectly dry. My best guess is that moisture built up under there due to humidity (I turned the ac off before I left) and became a perfect habitat for some bacteria colony.

Re: Has this ever happened to you?
 

It might be from the overflow pan in the bottom of the refrigerator. The great change in room temperature might have caused it to build up a lot of water when it defrosted.

Re: Has this ever happened to you?
 

haunted house

Re: Has this ever happened to you?
 

Do you have an ICE maker????

I found the same kind of Problem. it turned out to be a tiny tiny hole in the feed line for the ice maker.

and the water is so small, but after a few days, it collects somewhere. i.e. your Mat.