Record Display for the EPA National Library Catalog

RECORD NUMBER: 20 OF 20

OLS Field Name OLS Field Data
Main Title Use of the 'Ortho Effect' for Chlorinated Biphenyl and Brominated Biphenyl Isomer Identification.
Author Sovocool, G. W. ; Mitchum, R. K. ; Donnelly, J. R. ;
CORP Author Lockheed Engineering and Management Services Co., Inc., Las Vegas, NV.;Environmental Monitoring Systems Lab., Las Vegas, NV.
Year Published 1987
Report Number EPA-68-03-3249; EPA/600/J-87/292;
Stock Number PB88-185152
Additional Subjects Biphenyl ; Spectrum analysis ; Mass spectroscopy ; Fragmentation ; Isomerization ; Gas chromatography ; Halogens ; Reprints ; Polybromobiphenyl compounds ; Polychlorobiphenyl compounds ; Isomerism ; Mass fragmentography
Holdings
Library Call Number Additional Info Location Last
Modified
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Status
NTIS  PB88-185152 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 09/04/1988
Collation 6p
Abstract
The ortho effect observed for chlorinated biphenyls (PCBs) and brominated biphenyls (PBBs) having 2,2; 2,2', 6 or 2,2', 6,6' halogens, can be combined with GC retention index for isomer specific identifications by gas chromatography/mass spectrometry (GC/MS). This technique reliably allows accurate structure assignments for environmental monitoring without the use of multiple GC determinations that employ different chromatographic phases. Validation of the ortho effect for 129 PCBs and PBBs is reported, including a survey of all PCB mass spectra in the EPA/NIH mass spectral database. Presence or absence of ortho effect and reduction in magnitude for 2,2', 6,6' substitution may be related to the formation of a planar, bridged halonium ion intermediate upon electron ionization in the mass spectrometer. (Copyright (c) by John Wiley & Sons, Ltd.)