Regulations last checked for updates: May 18, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
§ 766.27 - Congeners and LOQs for which quantitation is required.

Quantitation at the target LOQ shown for each of the following HDDs/HDFs which may be present in the chemical substances is required for the chemical substances listed under § 766.25. Analysis must take place for either chlorinated or brominated dibenzodioxins or dibenzofurans, whichever is predominantly expected to occur in the chemical substance to be tested. Only chlorinated and brominated congeners need be quantified; for chemical substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only congeners totally brominated at the numbered positions need be quantified.

Chlorinated dioxins Brominated dioxins LOQ
2,3,7,8-TCDD2,3,7,8-TBDD0.1 ppb.
1,2,3,7,8-PeCDD1,2,3,7,8-PeBDD0.5 ppb.
1,2,3,4,7.8-HxCDD1,2,3,4,7,8-HxBDD2.5 ppb.
1,2,3,6,7,8-HxCDD1,2,3,6,7,8-HxBDD2.5 ppb.
1,2,3,7,8,9-HxCDD1,2,3,7,8,9-HxBDD2.5 ppb.
1,2,3,4,6,7,8-HpCDD1,2,3,4,6,7,8-HpBDD100 ppb.
2,3,7,8-TCDF2,3,7,8-TBDF1 ppb.
1,2,3,7,8-PeCDF1,2,3,7,8-PeBDF5 ppb.
2,3,4,7,8-PeCDF2,3,4,7,8-PeBDF5 ppb.
1,2,3,4,7,8-HxCDF1,2,3,4,7,8-HxBDF25 ppb.
1,2,3,6,7,8-HxCDF1,2,3,6,7,8-HxBDF25 ppb.
1,2,3,7,8,9-HxCDF1,2,3,7,8,9-HxBDF25 ppb.
2,3,4,6,7,8-HxCDF2,3,4,6,7,8-HxBDF25 ppb.
1,2,3,4,6,7,8-HpCDF1,2,3,4,6,7,8-HpBDF1 ppm.
1,2,3,4,7,8,9-HpCDF1,2,3,4,7,8,9-HpBDF1 ppm.
authority: 15 U.S.C. 2603 and 2607
source: 52 FR 21437, June 5, 1987, unless otherwise noted.
cite as: 40 CFR 766.27