Poisonous plants and ancient hunters: an analytical investigation into the presence of plant alkaloids on hunting tools from international museum collections

Introduction Many archaeologists believe that our early ancestors used poison to kill or incapacitate their prey using commonly found plants. It is believed that the hunting tools were dipped into a paste of the plant material containing alkaloids or cardenolides which in turn was used to aid in the process of hunting. Until now, very little scientific evidence has been available to support this claim. Aims The aim of this project is to analyse arrow heads and other hunting tools from international museum collections, for the presence of plant poisons by mass spectrometry and hyphenated techniques. It is also to initially establish if it is possible to detect the plant alkaloids after thousands of years and to consider the implications of the findings in relation to sample preparation/interpretation of results. Methods Plant standards were provided by Alnwick Gardens, Northumberland. A sample of curare was provided by the Pitt Rivers Museum (Oxford). Swabs of archaeological hunting tools have been provided by the Museum of Archaeology & Anthropology (Cambridge), the Pitt Rivers Museum (Oxford), and the Museo Etnografico Pigorini of Roma (Italy). LC-MS or MS analysis was carried out on the extracts from the swabs in comparison to the plant standards. Results Results have shown that it is possible to detect aconite in a pot 125 years old as well as alkaloids of the Strychnos species on arrow heads and darts swabbed in the museums. Current work includes the analysis of an arrow dating from 4000 BC, provided by the Phoebe A Hearst Museum of Berkeley (USA). Even though items were from the same collection, plant poisons were not found on all items when the same preparation and analysis technique were used. No information was provided with regards to where the samples were originally found or with respect to storage/cleaning therefore it is possible that the items may have come into contact with other poisoned items in the museum. Conclusion It is possible to detect plant poisons on hunting tools using MS and hyphenated chromatographic techniques. This work continues in the analysis of other archaeological artefacts from international museums.