Citation:

Grange, A H., W. Winnik, AND G W. Sovocool. DETERMINING ION COMPOSITIONS USING AN ACCURATE MASS, TRIPLE QUADRUPOLE MASS SPECTROMETER. Presented at American Society for Mass Spectrometry, Nashville, TN, May 23-27, 2004.

Impact/Purpose:

Provide state-of-the-science sampling, analysis, separation, and detection methods to allow rapid, accurate field and laboratory analyses of contaminated soils, sediments, biota, and groundwater to support Superfund clean-up decisions. Apply state-of-the-science methods in chemical analysis and data interpretation (e.g., mass spectral interpretation) to actual problems of OSWER, the Regions, and the States, in cooperation with the Las Vegas Technical Support Center as well as by direct contacts with Regional and State employees. Provide technical advice and guidance to OSWER using the environmental chemistry expertise (e.g., mass spectrometry, analytical methods development, clean-up methodology, inorganics, organometallics, volatile organics, non-volatile organics, semi-volatile organics, separation technologies, etc.) found within the branch.

Technical research support for various projects initiated either by Regions/Program Offices or ECB scientists. While these efforts will support the Regions and Program Offices, they cannot be predicted or planned in advance, and may serve multiple duty (e.g., solve real-world problems, serve to ground-truth analytical approaches that ECB is developing, transfer new technology). Many of the activities in this task support requests involving enforcement decisions and therefore are categorized as "environmental forensics".

Description:

For the past decade, we have used double focusing mass spectrometers to determine
compositions of ions observed in mass spectra produced from compounds introduced by GC
based on measured exact masses of the ions and their +1 and +2 isotopic profiles arising from atoms of heavier isotopes such as 13C, 15N, 170, 180, 33S, and 34S.ln addition, comparison of measured abundances of the +1 and +2 profiles relative to the monoisotopic ion profiles
discriminated among ion compositions that were possible based on monoisotopic ions' exact
masses and the error limits of their measurement. Measuring these three exact masses and two relative abundances increased 4-fold, the mass for which unique ion compositions can be determined.

Record Details: