Values for 2,3,7,8-TCDD Toxicity Equivalence Concentrations

Section 352 Section 352.302  Values for 2,3,7,8-TCDD Toxicity Equivalence Concentrations a)         For discharges in the Lake Michigan basin containing one or more 2,3,7,7,8-substituted chlorinated dibenzo- p -dioxins or 2,3,7,8-substituted dibenzofurans, the 2,3,7,8-TCDD toxicity equivalence concentration (TEC TCDD ) shall be determined as outlined in subsection (b). b)         The values listed in this Table 1 shall be used to determine the 2,3,7,8-TCDD toxicity equivalence concentrations using the following equation: TEC TCDD = ∑ C x TEF x BEF x where: TEC TCDD = 2,3,7,8-TCDD toxicity equivalence concentration in effluent C x = Concentration of total chemical x in effluent TEF x = TCDD toxicity equivalency factor for x BEF x = TCDD bioaccumulation equivalency factor for x TABLE 1 Congener TEF BEF 2,3,7,8-TCDD 1.0 1.0 1,2,3,7,8-PeCdd 0.5 0.9 1,2,3,4,7,8-HxCDD 0.1 0.3 1,2,3,6,7,8-HxCDD 0.1 0.1 1,2,3,7,8,9-HxCDD 0.1 0.1 1,2,3,4,6,7,8-HpCDD 0.01 0.05 OCDD 0.001 0.01 2,3,7,8-TCDF 0.1 0.8 1,2,3,7,8-PeCDF 0.05 0.2 2,3,4,7,8-PeCDF 0.5 1.6 1,2,3,4,7,8-HxCDF 0.1 0.08 1,2,3,6,7,8-HxCDF 0.1 0.2 2,3,4,6,7,8-HxCDF 0.1 0.7 1,2,3,7,8,9-HxCDF 0.1 0.6 1,2,3,4,6,7,8-HpCDF 0.01 0.01 1,2,3,4,7,8,9-HpCDF 0.01 0.4 OCDF 0.001 0.02