Dioxin and Dioxin-like Compounds; Toxic Equivalency Information; Community Right-To-Know Toxic Chemical Release Reporting

Under section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA), EPA is finalizing revisions to the reporting requirements for the dioxin and dioxin-like compounds category. The current EPCRA section 313 regulations require facilities to report dioxin and dioxin-like compounds in units of total grams for the entire category, and provide a single generic distribution of the individual dioxin and dioxin-like compounds at the facility. The final rule requires that, in addition to reporting total gram quantities for the category, facilities are required to report the mass quantity of each individual member of the category. The mass quantity data for the individual members of the category will be used by EPA to perform toxic equivalency (TEQ) computations which will be made available to the public. TEQs are a weighted quantity measure based on the toxicity of each member of the dioxin and dioxin-like compounds category relative to the most toxic members of the category, i.e., 2,3,7,8- tetrachlorodibenzo-p-dioxin and 1,2,3,7,8-pentachlorodibenzo-p-dioxin. The final rule also eliminates the reporting of the single generic distribution for the members of the dioxin and dioxin-like compounds category.