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Toxics Release Inventory (TRI) Program

2017 TRI National Analysis Dioxin and Dioxin-like Compounds and TEQ Data Files

Six data files represent all of the Toxics Release Inventory (TRI) dioxin and dioxin-like compounds data for reporting year 2017, including toxic equivalency (TEQ) data. There are seventeen distinct members of this chemical category listed under TRI. In addition to the total quantity (in grams) released for the entire dioxin category, facilities must report the quantity for each individual member. Dioxin data are reported on the TRI Form R Schedule 1.

Although useful, the total quantity of releases is not the best measure of the actual toxicity of dioxin and dioxin-like compounds because each compound has a different level of toxicity. To account for how these compounds vary in toxicity, EPA calculates weighted values called toxic equivalents (TEQs) from the individual mass quantity data reported by facilities and the associated Toxic Equivalency Factors (TEFs).

For detailed descriptions of the contents of these files, please see TRI TEQ Data Files Guide (PDF).

The types of Dioxin and Dioxin-like Compounds and TEQs Data Files are: