Polychlorinated dibenzodioxins and

Ecological danger of polychlorinated dibenzodioxines and dibenzofurans 97MI26, 97MI45, 98MI33, 98MI34. 

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... 

Polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs), in contrast to other chlorinated chemicals, have never been commercially manufactured nor are of any benefit or known use. PCDD/Fs are ubiquitous contaminants, which are released as byproducts of incomplete combustion or as impurities in chemical processes, and that their levels in the environment are increasing. 

Figure 10.4 The structures of polychlorinated dibenzodioxins and polychlorinated dibenzofurans...

Chlorinated micropoUutants are harmful for man and environment due to their toxicity, persistence, and bioaccumulation. Persistent compounds are very stable and difficult to get metabolized and mineralized by biological and chemical processes in the environment, and as a result, they have become ubiquitous in water, sediments, and the atmosphere bioaccumulation is the result of the lipophilicity of these compounds. Polychlorinated dibenzodioxins and -furans (PCDD/F) are not produced purposely like many of other chlorinated technical products, such as chlorinated biocides DDT, lindane, and toxaphene. The production and use of persistent organic pollutants (POPs), the dirty dozen has now been banned worldwide by the Stockholm protocol. It should be mentioned that about 3000 halogenated products have now been isolated as natural products in plants, microorganisms, and animals," but the total amount of these products is much smaller compared to xenobiotics. 

POLYCHLORINATED DIBENZODIOXINS AND FURANS AS POLLUTANTS FORMED IN INCINERATIONS... 

Boddington, J.M. Priority substances list assessment report No. 1 polychlorinated dibenzodioxins and polychlorinated dibenzofurans. Environment Canada. 56 p.. 1990. 

Mackay, D., W.-Y. Shiu, and K.C. Ma. 1992b. Illustrated Handbook of Physical - Chemical Properties and Environmental Fate of Organic Compounds. II. Polynuclear Aromatic Hydrocarbons, Polychlorinated Dibenzodioxins and Dibenzofurans. Lewis Publishers, Boca Raton, Florida, 597 pages. 

WHO has conducted three international studies of PCBs, polychlorinated dibenzodioxins, and polychlorinated dibenzo-furans in human milk during 1987-2003 (WHO 2000). The first two surveys were conducted in 1987-1988 and 1992-1993 in a number of European countries. The third, conducted in 2000-2003, included additional countries. A fourth survey has been developed with the intent to assess the persistent organic pollutants (POPs) found in human milk so that each country can better identify and set priorities among POPs for remedial action (WHO 2000). The sample population will include at least 50 mothers from each country who are planning to breastfeed (WHO 2005). Two sampling periods have been proposed, the first to obtain a baseline sample of POPs in representative... 

Flesch-Janys, D., H. Becher, P. Gurn, D. Jung, J. Konietzko, A. Manz, and O. Papke. 1996. Elimination of polychlorinated dibenzodioxins and dibenzofurans in occupationally exposed persons. J. Toxicol. Environ. Health Part A 47(4) 363-378. 

Consequently, they are able to integrate pollutant levels over a broad area by bioaccumulation (Furness, 1993). A bird egg, unlike a mammalian fetus, is an isolated and independent metabolic system. In addition, persistent, bioaccumulative and lipophilic pollutants (e.g. PCBs, polychlorinated dibenzodioxins and furans) are known to biomagnify in the egg yolk and result in concentrations of orders of magnitude higher than the ambient concentrations in the diet of the female bird (Kleinow et al., 1999). The contaminant levels in waterbird eggs, therefore, provide important and useful information for monitoring changes in environmental quality. 

Schecter, A., Furst, P., Furst, C., Meemken, H.A., Groebel, W., Vu, D.Q., 1989b. Levels of polychlorinated dibenzodioxins and dibezofurans in cow s milk and in soy bean derived infant formulas sold in the United States and other countries. Chemosphere 19, 913-918. 

Eschenroeder A, Jaeger RJ, Ospital JJ, et al. 1986. Health risk analysis of human exposures to soil amended with sewage sludge contaminated with polychlorinated dibenzodioxins and dibenzofurans. Vet Hum Toxicol 28 435-442. 

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

Huff JE, Moore JA, Saracci R, et al. 1980. Long-term hazards of polychlorinated dibenzodioxins and polychlorinated dibenzofiiians. Environ Health Perspect 36 221-240. 

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