ABSTRACT
Worldwide public concern of the toxicity of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) has catalyzed extensive research in many toxicologically related areas. New findings are reported yearly in several scientific meetings, including one international meeting, which concentrates primarily on PCDDs and PCDFs. None of these chemicals are produced for commercial purposes, but chlorinated dibenzo-p-dioxins and dibenzofurans are produced as trace contaminants in several chemical processes, primarily during the synthesis of chlorinated phenols. Thus, these compounds can enter the environment by a variety of means. Once there, they are remarkably stable, and many of these compounds, especially those that are substituted with chlorine at the 2,3,7,8 positions and that are also the most toxic, bioaccumulate in the human foodchain. PCDDs and PCDFs were first measured in the blood of workers from the sawmill, leather, and textile industries by Rappe et al.
