Dioxins and dioxin-like PCBs in fat food

Dioxin is the common name associated with polychlorinated dibenzo-p-dioxins (PCDD'S) and dibenzofurans (PCDFs). It includes 210 congeners of which 17 are considered the most toxic. Of the 209 Polychlorinated Biphenyls (PCBs) 12 of the most toxic congeners which exhibit a planar structure are considered to hove a dioxin-like toxicity. In 1998, the World Health Organization (WHO) assigned Toxic Equivalency Factors (TEF's) to these PCB and dioxins compounds which are used to assess the overall toxicity of samples (1-TEQ) relative to 2,3,7,8-TCDD, the Most toxic congener. Because these ubiquitous compounds accumulate in biological tissues and thus migrate up the food chain dioxins and PCBs have been in the environmental spotlight for over two decades. Both PCDD/F and PCB methods utilize isotope dilution combined with HRGC/HRMS to provide the lowest detection limits in a wide variety of compounds including vegetable oils and fats.