Variability in the chemical contamination effects of gun shot

This is a contribution to a larger study aimed at development of a technique to determine the origins of waterfowl from their feather chemistry, using automated X-ray fluorescence spectrometry. Since feather samples commonly come from shot birds, an effort was made to measure the contamination effects of shot using cotton cloth to simulate feathers. At pointblank ranges contamination can include the elements Ba, Sb, Pb, Cu, S and likely others depending on the exact composition of both gun powder and shot. At greater ranges (12.5 to 50 yards – 14.4 to 45 m) significant contamination resulting from 12 gauge No. 2 shot came only from lead, with some zinc contamination probable at the extreme range used. Lead contamination increased with increasing range, and apparently has a curvelinear relationship with pellet velocity. This knowledge might permit prediction, after the fact, of ranges from which shot has been fired.