New Optical Sensor Technology Measures Key Environmental Contaminants

Summary

Detection and measurement of amounts of traces of toxic chemicals is a necessary first step in the cleanup of environmental contamination. However, there are very few analytical techniques that have sufficient sensitivity to measure the low levels of many contaminants at the sites for which DOE is responsible for cleanup. Office of Science research at the National Institute for Standards and Technology (NIST) has demon­strated the suitability of a recently developed technique, cavity ring-down spectro­scopy, for measuring trace amounts of chemicals such as trichloroethylene (TCE) in the field. TCE is a major subsurface contaminant at several DOE sites. Its migration will have to be monitored at these sites for many years into the future. The NIST technique also shows promise for laboratory studies of the adsorption of molecules on surfaces, as a means of understanding chemical reactions such as those catalyzed by the surface. The studies by Andrew Pipino’s research group at NIST was funded by the Biological and Environmental Research Environmental Management Science Program. An article about the fundamental concept has just been published in the Journal of Chemical Physics.