This paper presents an unconventional way of detecting organic modifications in paints employing X-ray Spectroscopy (XRS) and Principal Component Analysis (PCA). For this purpose, three different paints (latex, corrective fluid and varnish) were applied onto wood substrates and then treated with infrared radiation and solar light at room temperature. X-ray fluorescence spectra were obtained using an Rh tube-EDXRF system, and PCA analysis was performed using the spectral region between 18 and 24 keV. The scores plots showed a clear paint classification and separation according to treatment. This separation was promoted by Compton and Rayleigh scatterings. This study opens up new possibilities for analysing different materials, and it presents a new field for XRS.1502131136