Radiocarbon Date Recovery from Bitumen- Containing Egyptian Embalming Resins

Human soft tissue specimens obtained by dissection of Greco-Roman Period mummies buried in the Dakhleh Oasis in Egypt's Western Desert had radiocarbon analytical results many of which were substantially older than accompanying artifacts suggested. Mass spectrometry suggested the presence of hydrocarbons. Gas chromatography/mass spectrometry (GCMS) confirmed that the “resin” applied to these bodies was a mixture of materials containing not only the expected plant sterols of ancient Egyptian embalming resins, but also insoluble carbonized plant material, beeswax and fossil asphalt (bitumen) in four analyzed “resin” samples. Two of these bore a geochemical signature characteristic of Dead Sea asphalt native samples. Efforts to recover the “true” radiocarbon dates by subjecting the tissue samples to extractions by light organic solvents were not reliably successful, probably due to the presence of “radiocarbon-dead” insoluble compounds. Historical evidence indicates that Palestine's Dead Sea bitumen was an item traded to Egypt for embalming purposes especially during the Ptolemaic and later Periods. When using mummified human tissues for radiocarbon dating of mummies from the later periods of ancient Egypt’s pharaonic period, possible contamination with such bitumen in amounts sufficient to alter radiocarbon dating tests should be kept in mind. Simple pre-analytical extraction with commonly available light organic solvents may not remove the offending compounds.