BLOOD RESIDUES ON STONE TOOLS - INDOOR AND OUTDOOR EXPERIMENTS

Three series of bloodstained flakes and bones were buried in soil out of doors, retrieved month by month, and tested using a sensitive and s pecific ELISA with monoclonal antibodies to see if any human albumin o r IgG, or bovine albumin, could be detected. A few tests were positive , including a scraper examined after twelve months' burial, but many w ere negative. A fourth series of bloodstained flakes kept in laborator y conditions tested highly positive for albumin and IgG after two year s. The results are compared with other experimental work and with publ ished identifications of blood from ancient sites, and factors which m ight have a significant effect on antigen survival are discussed.