This study presents UV spectral data for 39 aromatic amines and 3 nitroaromatic compounds and examines the influence on the compounds of short-term irradiation at 254 nm. It also gives some general characteristics of the UV spectra of irradiated and non-irradiated analytes. It was ascertained that nitro or aminonitro compounds are photochemically much more stable than aromatic amines without nitro substituents. Other substituents, for example -OH, -COOH, -SO3H, and -CH3, do not increase the photochemical stability. Therefore, the alteration of the UV spectra for the latter compounds can be used as an additional criterion for identification; this is shown with waste water from the site of a former ammunition plant as an example.