Each "Dioxin TEQ" data file accessible from this page contains the individually reported dioxin and dioxin-like compounds mass quantity data reported on the Toxics Release Inventory (TRI) Reporting Form R Schedule 1, with associated toxic equivalency data. Data are presented in .csv (comma-separated value) file format. For more information about using these files, see the TRI TEQ Data Files Guide (PDF).

There are 17 distinct members of the TRI dioxin and dioxin-like compounds chemical category. Facilities that have any of the information required by Reporting Form R Schedule 1 must submit individual dioxin member data via Schedule 1, in addition to completing the Reporting Form R. Quantities of dioxin and dioxin-like compounds are reported in grams.

To account for how dioxin and dioxin-like compounds vary in toxicity, EPA calculates weighted values called toxic equivalents (TEQs) using the individual mass quantity data reported by facilities and the associated Toxic Equivalency Factors (TEFs). TEQs allow for a better understanding of the toxicity of chemical releases at facilities that report to the TRI Program.