I am super sensitive to the smells of various things, especially in an enclosed area. Bug spray, paint, certain cleaning solutions/compounds, etc., will give me a killer headache to the point of making me physically ill. Worst of the lot is heated vinegar, as in how people will cycle vinegar through a coffee maker to clean it. First time that happened I was at work and an ambulance had to be called. There have been any number of times I've had to tell Mrs Duke that I needed to wait outside places we've gone to, the smell of something was getting to me.
On the plus side, nothing beats the smell of peat fire for me. Immediately brings to mind a pint of Smithwicks, a plate of hot lamb curry and chips (fries), and traditional Irish music. Also, there was a rose scented perfume a one time girl friend wore that brings back memories I can't really discuss on a family forum.