Polychlorinated dibenzodioxins determining

In general, capillary gas chromatography provides enough resolution for most determinations in environmental analysis. Multidimensional gas chromatography has been applied to environmental analysis mainly to solve separation problems for complex groups of compounds. Important applications of GC-GC can therefore be found in the analysis of organic micropollutants, where compounds such as polychlorinated dibenzodioxins (PCDDs) (10), polychlorinated dibenzofurans (PCDFs) (10) and polychlorinated biphenyls (PCBs) (11-15), on account of their similar properties, present serious separation problems. MDGC has also been used to analyse other pollutants in environmental samples (10, 16, 17). 

Investigations have shown that plants on thermal treatment of solid domestic waste represent the source of polychlorinated dibenzodioxins and biphenyls. In this connection, it is necessary to conduct further investigations of their emission and determination of all the range of PCDD, PCDF and PCB... 

Furst P, Meemken HA, Groebel W. 1986. Determination of polychlorinated dibenzodioxins and dibenzofurans in human milk. Chemosphere 15 1977-1980. 

Hagenmaier H, Brunner H, Haag R, Kraft M (1986), Fresenius Z. Anal. Chem. 323 24-28.. .Selective determination of 2,3,7,8-tetrachlordibenzo-p-dioxin in the presence of a large excess of other polychlorinated dibenzodioxins and polychlorinated dibenzofurans"... 

In addition to the thermogravimetry experiments, batch pyrolysis experiments continuously monitoring HCl formation were performed with PVC to determine the optimum temperature for HCl formation. Under conditions of maximum HCl formation, PVC was pyrolyzed with and without oxygen in a fluidized bed reactor and the formation of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) measured. Avoiding the formation of these highly toxic compounds would be a critical element in any waste stream processing scheme. 

The severe health effects observed in the Japanese Yusho incident of 1968 were attributed to the ingestion of polychlorinated biphenyls (PCBs). At that time, the forefront of analytical chemistry was represented by the determination of trace components at the parts per million (ppm) concentration level. It was not until about ten years later that analytical methodology was able to detect polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzodioxins (PCDDs) at concentrations of 10 parts per billion (ppb) or less in the presence of PCBs. The significance of the determinations lies in the assessment of risk to human populations exposed to undegraded PCBs and to mixtures of chemically similar compounds of concern derived from uncontrolled reactions such as might occur when a PCB filled transformer undergoes eventful failure. 

Methods for Determining Polychlorinated Dibenzodioxins and Polychlorinated Dibenzofurans... 

SW-846, is used to measure emissions of semivolatile principal organic constituents. Method 0010 is designed to determine destruction and removal efficiency (DRE) of POHCs from incineration systems. The method involves a modification of the EPA Method 5 sampling train and may be used to determine particulate emission rates from stationary sources. The method is applied to semivolatile compounds, including polychlorinated biphenyls (PCBs), chlorinated dibenzodioxins and dibenzofurans, polycyclic organic matter, and other semivolatile organic compounds. 

Cooke M, Hatchel JA, Czuczwa JM, et al. 1988. Analytical and sampling techniques for the determination of ultratrace quantities of polychlorinated dibenzofurans and dibenzodioxins. In Proceedings 1987 EPRI PCB Seminar, Kansas City, MO, October 6-9, 1987. Palo Alto, CA Electric Power Research Institute, 7-1 -7-8. 

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