Review Paper- Effects of Persistent Organic Pollutants on the Immune System: The Case of Dioxins

Persistent organic pollutants can be traced in air, water, soil and biota in industrialized and non industrialized regions. Although the production of these chemicals has been banned since 1980's when their toxicity was proven, their use, trade and disposal as well as persistence due to previous use, continues to contaminate the environment and threaten human health. Recent studies on the immunological consequences of dioxin contamination and exposure indicate that these compounds and specifically 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin activates the aryl hydrocarbon receptor on lymphocytes. This activation results in an array of effects on T, B and APC cells, biological mediators of the immune response and thereby results in suppression or remodelling of the immune response. This review attempts to shed light on the recent research developments in this field and to provide insight into the vast and long term health consequences of persistent organic pollutants.