Abstract
A flameless atomic absorption technique, employing a tantalum strip atomizer, has been developed to determine barium and antimony in gunshot residue. Cotton swabs, wetted with 5% HNO3, are used to collect residue. Barium and antimony are released from the swabs by acid leaching or plasma ashing. Both techniques give good recoveries; the ashing technique is preferred for blood-stained swabs. The sensitivity for barium is 0.1 ng/10 µl and antimony 0.2 ng/10 µl. At nanogram levels the standard relative deviation for barium is 8.3% and for antimony 8.5%.