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A NEW HIGH RESOLUTION MASS SPECTROMETRY TECHNIQUE FOR IDENTIFYING PHARMACEUTICALS AND POTENTIAL ENDOCRINE DISRUPTORS IN DRINKING WATER SOURCES
Citation:
Grange, A H. AND G W. Sovocool. A NEW HIGH RESOLUTION MASS SPECTROMETRY TECHNIQUE FOR IDENTIFYING PHARMACEUTICALS AND POTENTIAL ENDOCRINE DISRUPTORS IN DRINKING WATER SOURCES. Presented at National Ground Water Association Emerging Issues Conference, Minneapolis, MN, June 7-8, 1999.
Impact/Purpose:
The overall goals of the task are to apply NERL's core capability in advanced chemical science and technology for maximum benefit in estimating exposures of ecosystems and humans to chemical stressors and to identify emerging pollution concerns, in particular long-range airborne transport of contaminants. This task comprises several subtasks, each with individual objectives:
Subtask 1: screen exposures of National Park PRIMENet ecosystems to chemical stressors, identifying indications of exposure requiring further evaluation, and use these samples evaluate new analytical methods as replacements for standard methods in future assessments of ecosystem contaminant exposures.
Subtask 2: evaluate a new mercury analytical approach with superior performance on complex solid matrices such as biological tissues, and apply the approach to estimating exposure of ecosystems and humans to mercury.
Subtask 3: determine distribution patterns of chemical contaminants in the southern Sierra Nevada Range of California, investigate topographic and weather factors that may influence the distributions, and determine if a correlation exists between contaminant distributions and extirpation patterns of the mountain yellow-legged frog.
Subtask 4: provide analytical methods to measure a number of inorganic and organic arsenic species in a variety of environmental matrices, elucidate the environmental transformations undergone by organoarsenic animal-feed additives, and determine if the potential exists for substantially increased exposure of humans and aquatic organisms to arsenic.
Description:
A New High Resolution Mass Spectrometry Technique for Identifying Pharmaceuticals and Potential Endocrine Disruptors in Drinking Water Sources
Andrew H. Grange and G. Wayne Sovocool U.S.EPA, ORD, NERL, ESD, ECB, P.O. Box 93478, Las Vegas, NV 891933478
Mass spectra libraries do not encompass all compounds found in water from reservoirs, rivers, or wells. For trace-level compounds in complex sample extracts, low-quality low resolution mass spectra often yield poor library matches, which can lead to erroneous tentative identifications. Mass Peak Profiling from Selected Ion Recording Data (MPPSIRD) and a
Profile Generation Model (PGM) provide unique elemental compositions for ions with masses
up to 600 amu that contain C, H, 0, N, P, or S atoms. This knowledge greatly aids in identifying compounds for which no, or poor, library matches are found and can provide confirmatory evidence for good library matches. The utility of MPPSIRD and the PGM for compound identification will be illustrated for a tentatively identified pharmaceutical that was shown
instead to be a surface wetting agent used in non-ionic detergent formulations and for a series of high molecular weight brominated compounds produced by chlorination of water that contained bromide ion from a well near an animal feed lot.