Mass Spectrometer (IMAGE) DOE/Pacific Northwest National Laboratory Caption Scientist Tom Metz loads samples into a mass spectrometer at the Environmental Molecular Sciences Laboratory, a DOE national scientific user facility at PNNL. Credit Photo courtesy of PNNL Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.