Can Dioxin TEFs be Added?
Given the variable uncertainties associated with TEFs derived from a heterogeneous body of data, is it legitimate to add TEFs in the calculation of dioxin-TEQ? For such an important outcome as the calculation of dioxin toxicity, which will inform public health policy, it is important to ask this question. The measurement of the Ah receptor response to dioxin compounds may hold more promise for being an objective metric of dioxin toxicity than might dose-response data on laboratory animals. However, at the Toxicology Forum, Dr. Stephen Safe of Texas A&M University showed that interaction between various dioxin compounds (dioxins, furans and PCBs) and the Ah receptor varied substantially. This finding represents an obstacle to adding TEFs. In reality, dioxin compounds are only one family of chemical compounds that interact with the Ah receptor. Many other components of foods interact with the Ah receptor, some activating it and some inhibiting it. Thus, it is important to consider the co
