My neighbour stinks. No, really!

[CosmicGiggle]

What causes olfactory hallucinations (phantosmia)?

An olfactory hallucination (phantosmia) makes you detect smells that aren't really present in your environment.

The odors detected in phantosmia vary from person to person and may be foul or pleasant. They can occur in one or both nostrils. The phantom smell may seem to always be present or it may come and go.

Phantosmia may be caused by a head injury or upper respiratory infection. It can also be caused by temporal lobe seizures, inflamed sinuses, brain tumors and Parkinson's disease.

Consult your doctor if you experience the symptoms of phantosmia, so that your doctor can rule out any serious underlying disorders that may be causing the detected smell.

Parosmia is another smell disorder that's similar to phantosmia. But, in parosmia a smell that's present in your environment is distorted. Parosmia can occur with damage to the olfactory system, such as after a severe respiratory infection.

 

[Sunshineinabag]

Sniffing fakes

 

[Douglas.Curtis]

Construction foam insulation.

Drill a hole in the drywall less than the width of a pencil and just above the foundation. Insert the tube of a can of construction foam and spray. As a test first, spray something you can throw away to see how it expands, since you'll not want to bust out the wall at any point. Drill a couple holes along the area where you believe the issue is.
A small tub of drywall putty will fill the holes, and nearly any modern hardware store can match you a pint of paint to a chip of the wall color.

Nobody will ever know you did anything until they open the wall up at some point in the future.

 

[St. Phatty]

One more question to add from above:
Does your chewing gum lose its flavor on the bedpost overnight?

Sometimes I put chewing gum on the desk and then come back later and chew some more.

But usually I just put it in a Big Pile, which looks like a miniature Matterhorn.

 

[Sunshineinabag]

Pics please

 

[Treevly]

It is probably cause by ketoacidosis. I'd give odds, with real money.

"""Ketoacidosis With undiagnosed or inadequately controlled Type I diabetes, the body has trouble producing enough insulin to break down sugars for energy. Instead, the body burns fats. This leads to a buildup of acids called ketones in the blood and urine. The ketones can cause a distinctive fruity odor on your breath and body."""

I can also smell the herbicide Roundup when it is sprayed on crops. The chemical name for it is Glyphosate, which is a type of sugar molecule. For some reason I seem to have developed an ability to smell certain sugar molecules more than most people can. If the farmer across the road sprays, the smell goes away after one or two weeks. My neighbour doesn't.