Trace contaminant control onboard the International Space Station will be accomplished not only by the Trace Contaminant Control Subassembly but also by other Environmental Control and Life Support System subassemblies. These additional removal routes include absorption by humidity condensate in the Temperature and Humidity Control Condensing Heat Exchanger and adsorption by the Carbon Dioxide Removal Assembly. The Trace Contaminant Injection Test, which was performed at NASA's Marshall Space Flight Center in November and December 1997, investigated the system-level removal of some common spacecraft trace contaminants by these International Space Station systems and subsystem. It is a follow-on to the Integrated Atmosphere Revitalization Test conducted in 1996. An estimate for the magnitude of the assisting role provided by the Carbon Dioxide Removal Assembly and the Condensing Heat Exchanger was obtained. In addition, data on the purity of Carbon Dioxide Removal Assembly carbon dioxide product were obtained to support Environmental Control and Life Support System Air Revitalization Subsystem loop closure.