Decontamination of archaeological dental enamel for palaeoproteomics

Archaeological materials will accumulate contamination from sources such as handling and storage, which may affect downstream analyses. For dental enamel, it has often been assumed that removal of contamination is not necessary prior to palaeoproteomic analyses, due to the extraction protocols that are used, and relatively straightforward bioinformatic separation of contaminants and endogenous proteins. Here, we artificially contaminate Pleistocene Rhinoceros dental enamel with modern dog saliva, in order to evaluate the effects of contamination and to compare decontamination protocols. We find that although the contaminating proteins cannot be identified, contamination does lead to a significant loss of endogenous proteomic data. A comparison of published decontamination methods thereafter shows that a wash with water or bleach is most efficient at removing contamination.