[sp332]

Pretty small, but not cell-phone sized. https://www.amazon.com/MicrOptix-VSA-100-Analyzing-Spectroph...

Ones that detect particular contaminants can be a lot smaller, especially if they are single-use.

[isoprophlex]

That's a spectrophotometer, not a GC/MS... Can you detect smelly airborne chemicals with this as well?

[sp332]

Reading the description, it might be for liquids instead. Anyway it won't give as much information about the molecular components as a mass spectrometer, but you can still get a good idea if there are contaminants.