The ability of sorbent injection technology to reduce the potential for trace metal emissions from coal combustion was researched. Pilot scale tests of high-temperature furnace sorbent injection were accompanied by stack sampling for coal-based, metallic air toxics. Tested sorbents included hydrated lime, limestone, kaolinite, and bauxite injected at 1000, 1150, and 1300 degrees C, and through the burner at several feed rates. Continuous gas monitoring and solids sampling by particle size determined changes in metal concentrations from baseline measurements. The impact of sorbent injection on trace metal emissions is a function of metal type, sorbent type, and injection mode. Reductions in submicrometer concentrations of antimony, arsenic, mercury, and selenium were observed when hydrated lime and limestone were injected. The total amount of captured arsenic, cadmium, and lead increased when using, variously, hydrated lime, limestone, and kaolinite.