last summer i believed an odor coming out of my kitchen was coming down from the ceiling. I believed it was a dead something and I was NOT going to go looking for it. I called a Pest Removal Company. The man poked, proded, crawled around my attic in places I feared wasps would get him.
He came up with nothing. Yet the smell persisted in my kitchen. So he sniffed around discovering the odor was coming from around the old frig/freeze that had been in the kitchen since I was a teen.
Turns out all the dust and dog hair over 20 some years was getting to close to the compressor under the frig/freezer and burning it. The dust and fur got close to the compressor because something had made a nest under under my frig but when the man moved the frig/freezer it must have run behind my kitchen sink or something, either way it was gone. WHAT A STINK when the man pulled out all that old dust, fecal, dog hair, paper. No seads which meant my visitor was not a rodent, but cat size.....oppossum, raccoon, feral cat, something noctural. Why?>>>
I have a doggy door in the kitchen opening to a big private sun deck shaded by a huge pine tree. Anything could have come though that doggy door. The winter before something did and my ever so courageless dogs just watched 'the thing' travel up and down my hallway at night setting off interior motion detection lights.
Check the dust under your frig that it is not to close to the compressor running your frig. Then call Pest Control or Animal Control in your area or your local health dept. It is just not healthy living around that.
Oh call you local utility company sometimes natural gas coming out of the ground has a foul odor. Have your ground checked for leaks. If nothing bring the inspector in let them get a sniff, they might know what dept for you to call. Then it will not cost you anything.
The Pest Removel Man who only removed dust and dog hair from around my frig/freezer had me write a check for $250.