13C-Isotope ratio mass spectrometry as a potential tool for the forensic analysis of white architectural paint: a preliminary study

Paints have a dual role in society, to protect materials from environmental agents such as ultraviolet light, moisture and oxygen, and to make painted materials look more attractive. Variability in paint samples is often due to binder and pigment type within the sample. The most common resin used in decorative paints is drying oil alkyd resin, which incorporates soybean oil and vinyl acrylic based latexes. Traditional analytical methods used by forensic scientists may be able to say whether two paint samples are indistinguishable but cannot conclusively say that they both originate from the same source. To find out if isotopic composition can provide an added dimension of information, 28 different white architectural paints were analysed for (13)C abundance using isotope ratio mass spectrometry. In addition, variations in application, drying time and thickness were also investigated to assess the discriminatory power of (13)C data from white paints with an unknown history. Preliminary results indicate that this method could aid screening of paint samples.