Table 12 to Subpart DDDD of Part 63—Toxic Equivalency Factors

Dioxin/furan congener	Toxic equivalency factor	2,3,7,8-tetrachlorinated dibenzo-p-dioxin	1	1,2,3,7,8-pentachlorinated dibenzo-p-dioxin	1	1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin	0.1	1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin	0.1	1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin	0.1	1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin	0.01	octachlorinated dibenzo-p-dioxin	0.0003	2,3,7,8-tetrachlorinated dibenzofuran	0.1	2,3,4,7,8-pentachlorinated dibenzofuran	0.3	1,2,3,7,8-pentachlorinated dibenzofuran	0.03	1,2,3,4,7,8-hexachlorinated dibenzofuran	0.1	1,2,3,6,7,8-hexachlorinated dibenzofuran	0.1	1,2,3,7,8,9-hexachlorinated dibenzofuran	0.1	2,3,4,6,7,8-hexachlorinated dibenzofuran	0.1	1,2,3,4,6,7,8-heptachlorinated dibenzofuran	0.01	1,2,3,4,7,8,9-heptachlorinated dibenzofuran	0.01	octachlorinated dibenzofuran	0.0003

[91 FR 41463, July 6, 2026]