Polychlorinated dibenzofurans, quantitative

For halogenated aromatic hydrocarbons like polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), and polychlorinated dibenzo-p-dioxins (PCDDs) the binding to the aryl hydrocarbon (Ah) receptor regulates their toxicity [89]. The Ah receptor controls the induction of one of the cytochrome P450 enzymes in the liver. Toxic responses such as thymic atrophy, iveight loss, immu-notoxicity and acute lethality are associated ivith the relative affinity of PCBs, PCDFs and PCDDs for the Ah receptor [89]. The quantitative structure-activity relationship (QSAR) models predicting the affinity of the halogenated aromatic hydrocarbons ivith the Ah receptor describe the electron acceptor capability as well as the hydrophobicity and polarizability of the chemicals [89[. 

For the quantitative determination of polychlorinated diben-zodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), sample treatment and conservation play crucial roles, too. Only some of the 75 PCDD isomers and 135 PCDF isomers are highly toxic. The collection and analysis of the hazardous compounds present at ultratrace levels in environmental samples must preferably be isomer-specific. The exposure routes for these compounds originate from combustion processes (18-19). 

Tong HY, Karasek FW. 1986. Comparison of quantitation of polychlorinated dibenzodioxins and polychlorinated dibenzofurans in complex environmental samples by high resolution gas chromatography with flame ionization, electron capture and mass spectrometric detection. Chemosphere 15 1141-1146. 

Quantitative structure-retention relationships (QSSRs) have been established for polychlorinated dibenzofurans to assist their determination by gas chromatography (GC) <2002MI7, 2003ANC1049, 2005MI1683>. 

Hirokawa S, Imasaka T, Imasaka T. Chlorine substitution pattern, molecular electronic properties, and the nature of the ligand-receptor interaction Quantitative property-activity relationships of polychlorinated dibenzofurans. Chem Res Toxicol 2005 18 232-8. 

Holcomb M, Yao C, Safe S. 1988. Biologic and toxic effects of polychlorinated dibenzo-p-dioxin and dibenzofuran congeners in the guinea pig Quantitative structure-activity relationships. Biochem Pharmacol 37 1535-1539. 

Krishnan V, Safe S. 1993. Polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCFDs) as antiestrogens in MCF-7 human breast cancer cells Quantitative structure-activity relationships. Toxicol Appl Pharmacol 120 55-61. 

Oehme M, Mano S, Mikalsen A, et al. 1986. Quantitative method for the determination of femtogram amounts of polychlorinated dibenzo-p-dioxins and dibenzofurans in outdoor air. Chemosphere 15 607-617. 

Oehme, M., J. Klungs0yr, A. Biseth M. Schlabach, 1993. Quantitative determination of ppq-ppt levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in sediments from the Arctic (Barents Sea) and the North Sea. Anal. Method Instmm. 1 153-163. 

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