ABSTRACT
Halogenated aromatic hydrocarbons (HAHs), such as polychlorinated dibenzo-pdioxins (PCDDs), biphenyls (PCBs), and dibenzofurans (PCDFs) and related com pounds represent a diverse group of widespread environmental contaminants. PCDD and PCDF formation has been demonstrated to occur as a result of chlorine bleaching of wood pulp; during synthesis of various organochlorine products (such as the her bicide 2,4,5-T); during municipal, hospital, and industrial waste incineration; during
metal production and fossil fuel or wood burning as well as from a variety of other sources (1,2). PCBs, on the other hand, were produced commercially for use in trans formers, capacitors, heat transfer and hydraulic fluids, and other applications. It has been estimated that greater than 1.5 million metric tons of PCBs have been produced worldwide, with 20%-30% of this amount in the environment (1,3). HAHs represent a class of environmental chemicals that, because of their ubiquitous distribution, toxi city, fat solubility, resistance to biological and chemical degradation, and potential for bioaccumulation and biomagnification, can persist for long periods of time and thus could have a significant impact on the health and well-being of humans and animals (2, 3).
