Oana Marcu (SCR/SETI), Matt Lera (Lockheed Martin) and Chris McKay (SST) just completed a successful run at the SLAC X-ray beamline using a new environmental chamber. The small environmental chamber in which relative humidity could be controlled and monitored was constructed in the Space Science/Airborne Instrument Development laboratory in building N245 by Emmett Quigley. This chamber was designed to be placed in the X-ray microprobe beamline at the Stanford Synchrotron Radiation Lightsource (SSRL). Emissions from the X-rays allow for monitoring of the uptake and release of metals by organisms in response to desiccation stress as they are cyclicly exposed to dry conditions. This work is part of an exobiology funded project to investigate the response of Atacama desert organisms to reactive oxidant species.