ABSTRACT
This chapter describes some basic features of dioxins and related compounds and their influence on the environment. Recent laboratory studies have provided new insights into the mechanisms involved in the impact of dioxins on various cells and tissues and, ultimately, on toxicity. Dioxins have been demonstrated to be potent modulators of cellular growth and differentiation, particularly in epithelial tissues. The principal identified sources of environmental release of CDDs and CDFs may be grouped into four major types: These studies assume that emissions to air make up the major portion of dioxins released to the environment. Analyses of the mechanism of dioxin action in such systems appear likely to reveal additional factors that influence the susceptibility of a particular tissue to TCDD. Further analyses of dioxin action may provide more insight into the mechanisms by which TCDD and related compounds produce immunological effects, reproductive and/or developmental effects or cancer effects which are of particular public health concern.
