South Carolina Code of Regulations › Chapter 61 - DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL › Subchapter 61-79 - Hazardous Waste Management Regulations › Part 61-79.266 - STANDARDS FOR THE MANAGEMENT OF SPECIFIC HAZARDOUS WASTES AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES › Appendix 61-79.266.IX - Methods Manual for Compliance With the BIF Regulations Burning Hazardous Waste in Boilers and Industrial Furnaces › Section 61-79.266.4.0 - PROCEDURE FOR ESTIMATING THE TOXICITY EQUIVALENCY OF CHLORINATED DIBENZO-P-DIOXIN AND DIBENZOFURAN CONGENERS

Current through Register Vol. 48, No. 6, June 28, 2024
PCDDs and PCDFs must be determined using the method given
					 in section3.4 of this document. In this method, individual congeners or
					 homologues [FN1] are measured and then summed to yield a total PCDD/PCDF value.
					 No toxicity factors are specified in the method to compute risks from such
					 emissions.
For the purpose of estimating risks posed by emissions from
					 boilers and industrial furnaces, however, specific congeners and homologues
					 must be measured using the specified method and then multiplied by the assigned
					 toxicity equivalence factors (TEFs), using procedures described in "Interim
					 Procedures for Estimating Risks Associated with Exposures to Mixtures of
					 Chlorinated Dibenzo-p-Dioxins and Dibenzofurans (CDDs and CDFs) and 1989
					 Update," EPA/625/3-89/016, March 1989. The resulting 2,3,7,8-TCDD equivalents
					 value is used in the subsequent risk calculations and modeling efforts as
					 discussed in the BIF final rule.
The procedure for calculating the 2,3,7,8-TCDD equivalent
					 is as follows:
1. Using method 23,
				  determine the concentrations of 2,7,3,8-congeners of various PCDDs and PCDFs in
				  the sample.
2. Multiply the
				  congener concentrations in the sample by the TEF listed in Table 4.0-1 to
				  express the congener concentrations in terms of 2,3,7,8-TCDD equivalent. Note
				  that congeners not chlorinated at 2,3,7, and 8 positions have a zero toxicity
				  factor in this table.
3. Add the
				  products obtained in step 2, to obtain the total 2,3,7,8-TCDD equivalent in the
				  sample.
Sample calculations are provided in EPA document No.
					 EPA/625/3-89/016, March 1989, which can be obtained from the EPA, ORD
					 Publications Office, Cincinnati, Ohio (Phone no. 513-569-7562 ).
[FN1] FOOTNOTE: The term "congener" refers to any one
					 particular member of the same chemical family; e.g., there are 75 congeners of
					 chlorinated dibenzo-p-dioxins. The term "homologue" refers to a group of
					 structurally related chemicals that have the same degree of chlorination. For
					 example, there are eight homologues of CDs, monochlorinated through
					 octachlorinated. Dibenzo-p-dioxins and dibenzofurans that are chlorinated at
					 the 2,3,7, and 8 positions are denoted as "2378" congeners, except when
					 2,3,7,8-TCDD is uniquely referred to: e.g., 1,2,3,7,8-PeCDF and 2,3,4,7,8-
					 PeCDF are both referred to as "2378-PeCDFs."
Table 4.0-1.-2,3,7,8-TCDD Toxicity Equivalence
								  Factors (TEFs) [FN1]
Compound
I-TEFs, 89
Mono-, Di-, and TriCDDs
0
2,3,7,8-TCDD
1
Other TCDDs
0
2,3,7,8-PeCDD
0.5
Other PeCDDs
0
2,3,7,8-HxCDD
0.1
Other HxCDDs
0
2,3,7,8-HpCDD
0.01
Other HpCDDs
0
OCDD
0.001
Mono-, Di-, and TriCDFs
0
2,3,7,8-TCDF
0.1
Other TCDFs
0
1,2,3,7,8-PeCDF
0.05
2,3,4,7,8-PeCDF
0.5
Other PeCDFs
0
2378-HxCDFs
0.1
Other HxCDFs
0
2378-HpCDFs
0.01
Other HpCDFs
0
OCDF
0.001
Reference: Adopted from NATO/CCMS, 1988a.
[FN1] FOOTNOTE: Interim Procedures for Estimating
								  Risks Associated with Exposures to Mixtures of Chlorinated Dibenzo-p-Dioxins
								  and Dibenzofurans (CDDs and CDFs) 1989 Update EPA/625/3-89/016, March
								  1989.