PCDDPCDF

PCDD/PCDF refers to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, a class of chemically related chlorinated organic compounds. They are collectively known as dioxins and furans and are notable for their environmental persistence, tendency to bioaccumulate in fatty tissues, and potential for adverse health effects. They are often studied as a subgroup within persistent organic pollutants.

The term covers many individual congeners that differ by the number and positions of chlorine atoms. There are 210 possible PCDD/PCDF congeners, and risk assessments typically express their combined toxicity using toxic equivalency factors (TEFs) relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

PCDDs and PCDFs are not intentionally produced for commercial use. They generally arise as byproducts of various combustion and industrial processes, including waste incineration, energy generation, metal processing, and chlorine bleaching. They can form when organic matter is exposed to chlorine at high temperatures, leading to presence in air, soil, sediment, and water bodies. Dietary exposure, especially through fatty animal products, is a major route of human intake.

Health effects associated with PCDD/PCDF exposure include cancer, developmental and reproductive toxicity, and immunotoxicity. The severity of effects depends on the specific mixture of congeners, dose, and exposure duration; ingestion is the primary human exposure pathway. Risk assessment emphasizes the cumulative toxicity of mixtures using TEFs.

Regulatory responses focus on emission reduction and exposure control. Internationally, the Stockholm Convention on Persistent Organic Pollutants targets PCDD/PCDF for reduction and elimination. Monitoring programs and standardized analytical methods (e.g., HRGC/HRMS) are employed to measure levels in environmental samples and foods.