For the past several years more and more interest has been shown in the polychlorinated dibenzo-p-dioxins (CDD's) and even more recently the chlorinated dibenzofurans (CDF's). This is not surprising in view of the extreme toxicities, mutagenicity, carcinogenicity or teratogenicity shown by at least some of the members of this group; namely, the 2,3,7,8 and 1,2,3,7,8 substituted moieties. The CDD's include 75 possible substances while there are a series of 135 compounds for the CDF's. At least trace amounts of many of these substances are produced in a variety of industrial processes such as in the production of chlorophenols, herbicides, insecticides, etc. Also many are apparently generated in incineration processes. The chemical analysis problem for these substances is formidable in view of their similarities and their occurrence together. To date, the methods involve at least one and sometimes several forms of chromatography for either separation and sequencing to a detector or a pre-detection clean-up. The only detector to date which appears acceptable for final identification and quantification is the mass spectrometer. Depending on the sample pre-treatment, it may be low or high resolution and the levels of detection sought in the part per trillion range. This proposal suggests the use of chromatographically coupled atomic plasma emission spectrometry to provide alternate selective and specific detection at trace levels (less than or equal to pg/sec) for CDD's and CDF's. It is proposed that optical emission spectrometry will not only provide a reliable measure of quantification but, identification as well. Multichannel (polychromator) detection provides the highly desirable potential for elemental ratioing (empirical formula) for each GC peak as it elutes. Also by detecting in the multichannel mode, chromatographic ambiguity may be removed and allow relaxation of chromatographic constraints.
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