Code of Vermont Rules
Agency 12 - AGENCY OF NATURAL RESOURCES
Sub-Agency 032 - WASTE MANAGEMENT DIVISION
Chapter 012 - VERMONT GROUNDWATER PROTECTION RULE AND STRATEGY
Section 12 032 012 - VERMONT GROUNDWATER PROTECTION RULE AND STRATEGY
Current through August, 2024
Appendix D Hazardous Materials Listing
Pursuant to 10 V.S.A. § 6602(16)(A)(iv) any chemical or substance listed in the following table is a hazardous material.
CAS Number |
Chemical Name |
335-67-1 |
perfluorooctanic acid (PFOA) |
1763-23-1 |
perfluoro-octane sulfonic acid (PFOS) |
355-46-4 |
perfluorohexane sulfonic acid (PFHxS) |
375-85-9 |
perfluoroheptanoic acid (PFHpA) |
375-95-1 |
perfluorononanoic acid (PFNA) |
Section D1 HAZARDOUS MATERIALS LISTING
Pursuant to 10 V.S.A. § 6602(16)(A)(iv) any chemical or substance listed in the following table is a hazardous material.
CAS Number |
Chemical Name |
335-67-1 |
perfluorooctanic acid (PFOA) |
1763-23-1 |
perfluoro-octane sulfonic acid (PFOS) |
355-46-4 |
perfluorohexane sulfonic acid (PFHxS) |
375-85-9 |
perfluoroheptanoic acid (PFHpA) |
375-95-1 |
perfluorononanoic acid (PFNA) |
Appendix E Cumulative Risk Assessments
Nota bene: risk-based concentration (rbc) means the calculated concentration of a chemical (or group of chemicals) in an environmental medium estimated to correspond to a fixed level of risk e.g., a target Hazard Quotient (THQ) of 1.0 for noncarcinogenic (systemic, threshold) effects or target incremental lifetime cancer risk (ILCR) of one-in-one-million (1x10 [-6) ], for a predefined hypothetical human exposure scenario. Examples of rbcs for different environmental media based on different hypothetical exposure scenarios are included in this appendix as Tables 1-3.
I. SAMPLE-WISE APPROACH
For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):
For a given chemical i in sample j:
For a given number of chemicals (n) in sample j, where i is the first chemical:
For given a chemical i in sample j:
For a given number of chemicals (n) in sample j, where i is the first chemical:
Example Sample-wise Calculation for Direct Contact to Soil: Residential Scenario
Analyte |
Soil Sample S01 (mg/kg) |
Benzene |
4.00E-01 |
Ethylbenzene |
6.00E+00 |
Analyte |
Sample Concentration Soil Sample S01 (mg/kg) |
Resident - Soil rbcs from Table 1 |
|
rbccancer * (mg/kg) |
rbcnoncancer * (mg/kg) |
||
Benzene |
4.00E-01 |
6.98E-01 |
1.11E+02 |
Ethylbenzene |
6.00E+00 |
3.68E+00 |
4.45E+02 |
[*] Cancer rbcs are based on target ILCR=1E [-06; ] noncancer rbcs are based on target HQ=1.0
Resident - Soil |
|||||
CANCER |
NONCANCER |
||||
Analyte |
Site Concentration Sample S01 (mg/kg) |
a rbccancer (mg/kg) |
Sample S01 ILCR (unitless) |
b rbcnoncancer (mg/kg) |
Sample S01 HQ (unitless) |
Benzene |
4.00E-01 |
6.98E-01 |
5.73E-07 |
1.11E+02 |
3.60E-02 |
Ethylbenzene |
2.00E+00 |
3.68E+00 |
1.63E-06 |
4.45E+02 |
1.35E-02 |
Sample S01 Cumulative ILCR = |
2.20E-06 |
Sample S01 Hazard Index = |
4.95E-01 |
Is 2.20E [-06 ]>1E [-06 ]?
Yes
Is 4.59E [-01 ]>1
No
II. SITE-WIDE/EXPOSURE UNIT APPROACH: Summary Statistic used as Exposure Point Concentration
For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):
For given chemical i:
For a given number of chemicals ( n), where i is the first chemical:
For given chemical i:
For a given number of chemicals ( n), where i is the first chemical:
Example Site-wide Calculation for Direct Contact to Soil: Residential Scenario
Analyte |
Soil Exposure Point Concentration (mg/kg) |
Benzene |
4.00E-01 |
Ethylbenzene |
6.00E+00 |
Resident - Soil rbcs from Table 1 |
|||
Analyte |
Soil Concentration (mg/kg) |
rbccancer* (mg/kg) |
rbcnoncancer* (mg/kg) |
Benzene |
4.00E-01 |
6.98E-01 |
1.11E+02 |
Ethylbenzene |
6.00E+00 |
3.68E+00 |
4.45E+02 |
[* ] Cancer rbcs are based on a target ICLR=1E [-06; ] noncancer rbcs are based on target HQ=1.0
Resident - Soil |
|||||
CANCER |
NONCANCER |
||||
Analyte |
Site Exposure Point Concentration (mg/kg) |
a rbccancer (mg/kg) |
Site ILCR (unitless) |
b rbcnoncancer (mg/kg) |
Site HQ (unitless) |
Benzene |
4.00E-01 |
6.98E-01 |
5.73E-07 |
1.11E+02 |
3.60E-02 |
Ethylbenzene |
2.00E+00 |
3.68E+00 |
1.63E-06 |
4.45E+02 |
1.35E-02 |
Site Cumulative ILCR = |
2.20E-06 |
Site Hazard Index = |
4.95E-01 |
Is 2.20E [-06 ]>1E [-06 ]?
Yes
Is 4.95E [-01 ]>1
No
Because the Cumulative Site ILCR is greater than the target cancer risk for the site, further attention is warranted.
TABLE 1
SUMMARY TABLE
2019 - RESIDENT SOIL RISK-BASED CONCENTRATIONS (RBCS) (MG/KG)
INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION
Chemical Name |
CAS No. |
Resident - Soil risk-based concentations (rbcs) |
|
Cancer Target Risk=1E-6 |
Noncancer Hazard Quotient=1 |
||
Combined Routes mg/kg |
Combined Routes mg/kg |
||
Acetochlor |
34256-82-1 |
NA |
1.22E+03 |
Acetone |
67-64-1 |
NA |
4.06E+04 |
Alachlor |
15972-60-8 |
NA |
6.08E+01 |
Aldrin |
309-00-2 |
2.02E-02 |
2.10E+00 |
Aluminum |
7429-90-5 |
NA |
7.25E+04 |
Antimony |
7440-36-0 |
NA |
2.60E+01 |
Arsenic, Inorganic |
7440-38-2 |
2.32E-01 |
2.10E+01 |
Barium |
7440-39-3 |
NA |
1.12E+04 |
Benomyl |
17804-35-2 |
1.16E+02 |
7.90E+02 |
Benzene |
71-43-2 |
6.98E-01 |
1.11E+02 |
Benzo(a)pyrene (a) |
50-32-8 |
7.28E-02 |
1.72E+01 |
Beryllium |
7440-41-7 |
5.67E+02 |
3.45E+01 |
Bis(2-chloro-1-methyl ethyl)ether |
108-60-1 |
NA |
2.80E+03 |
Boron |
7440-42-8 |
NA |
1.47E+04 |
Bromate |
15541-45-4 |
5.36E-01 |
2.93E+02 |
Bromochloromethane |
74-97-5 |
NA |
1.93E+02 |
Bromoxynil |
1689-84-5 |
2.69E+00 |
9.12E+02 |
Butylbenzene, n- |
104-51-8 |
NA |
3.50E+03 |
Butylbenzene, sec- |
135-98-8 |
NA |
7.01E+03 |
Butylbenzene, tert- |
98-06-6 |
NA |
7.01E+03 |
Cadmium (food) |
7440-43-9 |
7.56E+02 |
6.86E+00 |
Carbaryl |
63-25-2 |
3.17E+02 |
6.08E+03 |
Carbon Disulfide |
75-15-0 |
NA |
6.08E+02 |
Carbon tetrachloride |
56-23-5 |
3.72E-01 |
1.30E+02 |
Chlorobenzene |
108-90-7 |
NA |
4.14E+02 |
Chromium (III) (insoluble salts) |
16065-83-1 |
NA |
4.02E+04 |
Chromium (VI) |
18540-29-9 |
9.06E-02 |
1.16E+02 |
Cobalt |
7440-48-4 |
1.51E+02 |
2.19E+01 |
Copper |
7440-50-8 |
NA |
1.04E+04 |
Di (2-ethylhexyl) phthalate |
117-81-7 |
1.98E+01 |
1.22E+03 |
Dibromochloropropane |
96-12-8 |
6.00E-03 |
6.63E+00 |
Dibromoethane, 1,2- |
106-93-4 |
2.27E-02 |
1.15E+02 |
Dichloroethane, 1,1- |
75-34-3 |
2.10E+00 |
1.40E+04 |
Dichloroethane, 1,2- |
107-06-2 |
2.85E-01 |
4.95E+01 |
Dichloroethylene, cis 1,2- |
156-59-2 |
NA |
1.40E+02 |
Dichloroethylene, trans 1,2- |
156-60-5 |
NA |
1.40E+03 |
Dichloropropane, 1,2- |
78-87-5 |
1.51E+00 |
2.63E+01 |
Dioxane, 1,4- |
123-91-1 |
2.78E+00 |
1.05E+03 |
Ethylbenzene |
100-41-4 |
3.68E+00 |
4.45E+02 |
Fluoranthene |
206-44-0 |
NA |
2.30E+03 |
Fluorene |
86-73-7 |
NA |
2.30E+03 |
Hexachlorobenzene |
118-74-1 |
1.31E-01 |
5.61E+01 |
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) |
121-82-4 |
4.60E+00 |
2.90E+02 |
Iron |
7439-89-6 |
NA |
5.13E+04 |
Isopropylbenzene (cumene) |
98-82-8 |
NA |
2.56E+02 |
Manganese (non-diet) |
7439-96-5 |
NA |
1.12E+03 |
Mercury (elemental) |
7439-97-6 |
NA |
3.13E+00 |
Methyl ethyl ketone |
78-93-3 |
NA |
1.70E+04 |
Methyl tert-butyl ether (MTBE) |
1634-04-4 |
NA |
6.49E+02 |
Molybdenum |
7439-98-7 |
NA |
3.66E+02 |
Naphthalene |
91-20-3 |
2.72E+00 |
2.24E+02 |
Nickel |
7440-02-0 |
5.23E+03 |
9.40E+02 |
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) |
2691-41-0 |
NA |
3.70E+03 |
Pentachlorophenol |
87-86-5 |
4.84E-01 |
2.37E+02 |
Pentaerythritol tetranitrate (PETN) |
78-11-5 |
NA |
1.22E+02 |
Perchlorate |
14797-73-0 |
NA |
5.13E+01 |
Perfluoroheptanoic acid (PFHpA) (b) |
375-85-9 |
NA |
1.22E+00 |
Perfluorohexane sulfonic acid (PFHxS) (b) |
355-46-4 |
NA |
1.22E+00 |
Perfluorononanoic acid (PFNA) (b) |
375-95-1 |
NA |
1.22E+00 |
Perfluorooctane sulfonic acid (PFOS) (b) |
1763-23-1 |
NA |
1.22E+00 |
Perfluorooctanoic acid (PFOA) (b) |
335-67-1 |
3.96E+00 |
1.22E+00 |
Polychlorinated biphenyls (c)(PCBs) |
1336-36-3 |
1.14E-01 |
1.13E+00 |
Propoxur (Baygon) |
114-26-1 |
7.88E+01 |
2.43E+02 |
Propyl benzene, n- |
103-65-1 |
NA |
2.53E+02 |
Selenium |
7782-49-2 |
NA |
3.66E+02 |
Silver |
7440-22-4 |
NA |
2.37E+02 |
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD) |
1746-01-6 |
2.25E-06 |
4.91E-05 |
Tetrachloroethane, 1,1,1,2- |
630-20-6 |
1.32E+00 |
2.10E+03 |
Tetrachloroethylene |
127-18-4 |
2.38E+00 |
1.13E+02 |
Thallium (soluble Thallium) |
7440-28-0 * |
NA |
7.33E-01 |
Toluene |
108-88-3 |
NA |
7.06E+02 |
Trichloroethylene (non-moa / mmoa) |
79-01-6 |
6.81E-01 |
6.21E+00 |
Trichloropropane, 1,2,3- |
96-18-4 |
3.11E-03 |
8.67E+00 |
Trimethylbenzene, 1,2,3- (d) |
526-73-8 |
NA |
2.06E+02 |
Trimethylbenzene, 1,2,4- (d) |
95-63-6 |
NA |
1.66E+02 |
Trimethylbenzene, 1,3,5- (d) |
108-67-8 |
NA |
1.44E+02 |
Trinitrotoluene, 2,4,6- (TNT) |
118-96-7 |
1.15E+01 |
3.49E+01 |
Uranium (soluble salts) |
NA |
NA |
4.40E+01 |
Vanadium |
7440-62-2 |
NA |
2.77E+00 |
Vinyl chloride |
75-01-4 |
9.83E-02 |
8.51E+01 |
Xylenes |
1330-20-7 |
NA |
2.52E+02 |
Zinc |
7440-66-6 |
NA |
2.20E+04 |
TABLE 3
SUMMARY TABLE
2019 - RESIDENT AND NONRESIDENTIAL INDOOR AIR risk-based concentrations (rbcs) (5g/m [3) ]
INHALATION
Chemical Name |
CAS No. |
Indoor Air risk-based concentrations (rbcs) |
|||
Resident - Indoor Air |
Nonresidential - Indoor Air |
||||
Cancer Target Risk = 1x10-6 |
Noncancer Hazard Quotient = 1.0 |
Cancer Target Risk = 1x10-6 |
Noncancer Hazard Quotient = 1.0 |
||
Inhalation µg/m3 |
Inhalation µg/m3 |
Inhalation µg/m3 |
Inhalation µg/m3 |
||
Benzene |
71-43-2 |
0.13 |
30.00 |
1.05 |
105.12 |
Carbon tetrachloride |
56-23-5 |
0.17 |
100.00 |
1.36 |
350.40 |
Chloroethane |
75-00-3 |
-- |
10000.00 |
-- |
35040.00 |
Chloroform |
67-66-3 |
0.04 |
97.70 |
0.36 |
342.34 |
Dichloroethane, 1,1- |
75-34-3 |
0.63 |
-- |
5.11 |
-- |
Dichloroethene, 1,1- |
75-35-4 |
-- |
200.00 |
-- |
700.80 |
Ethylbenzene |
100-41-4 |
4.00E-01 |
260.00 |
3.27E+00 |
911.04 |
Mercury (elemental) |
7439-97-6 |
-- |
0.30 |
-- |
0.3 (a) |
Methylene chloride |
75-09-2 |
60.34 |
600.00 |
817.60 |
2102.40 |
Naphthalene |
91-20-3 |
0.03 |
3.00 |
0.24 |
10.51 |
Tetrachloroethylene |
127-18-4 |
0.63 |
40.00 |
5.11 |
140.16 |
Trichloroethylene |
79-01-6 |
0.20 |
0.2 (c) |
1.99 |
0.7 (b) |
Trimethylbenzene, 1,2,3- |
526-73-8 |
-- |
60 (c) |
-- |
210.24 (c) |
Trimethylbenzene, 1,2,4- |
95-63-6 |
-- |
60 (c) |
-- |
210.24 (c) |
Trimethylbenzene, 1,3,5- |
108-67-8 |
-- |
60 (c) |
-- |
210.24 (c) |
Vinyl chloride |
75-01-4 |
0.11 |
100.00 |
1.86 (d) |
350.40 |
* - CAS Number is for Metallic Thallium
Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.
Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.
All cancer-based soil inhalation screening values were less than respective Csat thus no substitutions.
Noncancer-based soil inhalation screening value above respective Csat thus Csat substitiouion employed for the following:
Acetone, Carbon Disulfide, Ethylbenzene, Isopropylbenzene (cumene), Mercury (elemental), Methyl ethyl ketone, Methyl tert-butyl ether, n-Propyl benzene, Tetrachloroethylene, Toluene, Trimethyl benzenes, Xylenes.
TABLE 2
SUMMARY TABLE
2019 - COMMERCIAL WORKER SOIL risk-based concentrations (rbcs) (mg/kg)
INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION
Chemical Name |
CAS No. |
Commerical Worker - Soil risk-based concentations (rbcs) |
|
Cancer Target Risk=1E-6 |
Noncancer Hazard Quotient=1 |
||
Combined Routes mg/kg |
Combined Routes mg/kg |
||
Acetochlor |
34256-82-1 |
- |
1.44E+04 |
Acetone |
67-64-1 |
- |
1.00E+05 |
Alachlor |
15972-60-8 |
- |
7.18E+02 |
Aldrin |
309-00-2 |
9.76E-02 |
2.15E+01 |
Aluminum |
7429-90-5 |
- |
9.42E+05 |
Antimony |
7440-36-0 |
- |
3.19E+02 |
Arsenic, Inorganic |
7440-38-2 |
1.41E+00 |
2.71E+02 |
Barium |
7440-39-3 |
- |
1.27E+05 |
Benomyl |
17804-35-2 |
7.01E+02 |
9.34E+03 |
Benzene |
71-43-2 |
4.19E+00 |
4.18E+02 |
Benzo(a)pyrene (a) |
50-32-8 |
1.54E+00 |
1.94E+02 |
Beryllium |
7440-41-7 |
4.63E+03 |
2.89E+02 |
Bis(2-chloro-1-methyl ethyl)ether |
108-60-1 |
- |
3.63E+04 |
Boron |
7440-42-8 |
- |
1.96E+05 |
Bromate |
15541-45-4 |
3.27E+00 |
3.92E+03 |
Bromochloromethane |
74-97-5 |
- |
5.97E+02 |
Bromoxynil |
1689-84-5 |
1.63E+01 |
1.08E+04 |
Butylbenzene, n- |
104-51-8 |
- |
5.11E+04 |
Butylbenzene, sec- |
135-98-8 |
- |
1.02E+05 |
Butylbenzene, tert- |
98-06-6 |
- |
1.02E+05 |
Cadmium (food) |
7440-43-9 |
6.18E+03 |
8.72E+01 |
Carbaryl |
63-25-2 |
1.91E+03 |
7.18E+04 |
Carbon Disulfide |
75-15-0 |
- |
6.62E+02 |
Carbon tetrachloride |
56-23-5 |
2.23E+00 |
3.59E+02 |
Chlorobenzene |
108-90-7 |
- |
7.26E+02 |
Chromium (III) (insoluble salts) |
16065-83-1 |
- |
3.60E+05 |
Chromium (VI) |
18540-29-9 |
1.75E+00 |
1.14E+03 |
Cobalt |
7440-48-4 |
1.24E+03 |
2.91E+02 |
Copper |
7440-50-8 |
- |
1.39E+05 |
Di (2-ethylhexyl) phthalate |
117-81-7 |
1.20E+02 |
1.44E+04 |
Dibromochloropropane |
96-12-8 |
6.15E-02 |
2.75E+01 |
Dibromoethane, 1,2- |
106-93-4 |
1.39E-01 |
3.49E+02 |
Dichloroethane, 1,1- |
75-34-3 |
1.26E+01 |
2.04E+05 |
Dichloroethane, 1,2- |
107-06-2 |
1.71E+00 |
1.40E+02 |
Dichloroethylene, cis 1,2- |
156-59-2 |
- |
1.81E+03 |
Dichloroethylene, trans 1,2- |
156-60-5 |
- |
1.81E+04 |
Dichloropropane, 1,2- |
78-87-5 |
9.06E+00 |
6.81E+01 |
Dioxane, 1,4- |
123-91-1 |
1.69E+01 |
4.49E+03 |
Ethylbenzene |
100-41-4 |
2.21E+01 |
4.73E+02 |
Fluoranthene |
206-44-0 |
- |
2.64E+04 |
Fluorene |
86-73-7 |
- |
2.64E+04 |
Hexachlorobenzene |
118-74-1 |
6.86E-01 |
5.74E+02 |
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) |
121-82-4 |
2.80E+01 |
3.84E+03 |
Iron |
7439-89-6 |
- |
6.86E+05 |
Isopropylbenzene (cumene) |
98-82-8 |
- |
2.64E+02 |
Manganese (non-diet) |
7439-96-5 |
- |
1.14E+04 |
Mercury (elemental) |
7439-97-6 |
- |
3.13E+00 |
Methyl ethyl ketone |
78-93-3 |
- |
2.70E+04 |
Methyl tert-butyl ether (MTBE) |
1634-04-4 |
- |
4.46E+03 |
Molybdenum |
7439-98-7 |
- |
4.90E+03 |
Naphthalene |
91-20-3 |
1.64E+01 |
6.78E+02 |
Nickel |
7440-02-0 |
4.28E+04 |
9.71E+03 |
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) |
2691-41-0 |
- |
4.98E+04 |
Pentachlorophenol |
87-86-5 |
2.90E+00 |
2.48E+03 |
Pentaerythritol tetranitrate (PETN) |
78-11-5 |
- |
1.44E+03 |
Perchlorate |
14797-73-0 |
- |
6.86E+02 |
Perfluoroheptanoic acid (PFHpA) (b) |
375-85-9 |
- |
remove |
Perfluorohexane sulfonic acid (PFHxS) (b) |
355-46-4 |
- |
1.44E+01 |
Perfluorononanoic acid (PFNA) (b) |
375-95-1 |
- |
1.44E+01 |
Perfluorooctane sulfonic acid (PFOS) (b) |
1763-23-1 |
- |
1.44E+01 |
Perfluorooctanoic acid (PFOA) (b) |
335-67-1 |
2.39E+01 |
1.44E+01 |
Polychlorinated biphenyls (PCBs) (c) |
1336-36-3 |
6.83E-01 |
1.28E+01 |
Propoxur (Baygon) |
114-26-1 |
4.76E+02 |
2.87E+03 |
Propyl benzene, n- |
103-65-1 |
- |
2.61E+02 |
Selenium |
7782-49-2 |
- |
4.90E+03 |
Silver |
7440-22-4 |
- |
2.48E+03 |
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD) |
1746-01-6 |
1.37E-05 |
6.35E-04 |
Tetrachloroethane, 1,1,1,2- |
630-20-6 |
8.00E+00 |
3.07E+04 |
Tetrachloroethylene |
127-18-4 |
1.43E+01 |
1.51E+02 |
Thallium (soluble Thallium) |
7440-28-0 * |
- |
1.96E+05 |
Toluene |
108-88-3 |
- |
7.98E+02 |
Trichloroethylene (non-moa) |
79-01-6 |
6.47E+00 |
1.86E+01 |
Trichloropropane, 1,2,3- |
96-18-4 |
7.05E-02 |
2.29E+01 |
Trimethylbenzene, 1,2,3- (d) |
526-73-8 |
- |
2.82E+02 |
Trimethylbenzene, 1,2,4- (d) |
95-63-6 |
- |
2.12E+02 |
Trimethylbenzene, 1,3,5- (d) |
108-67-8 |
- |
1.77E+02 |
Trinitrotoluene, 2,4,6- (TNT) |
118-96-7 |
7.00E+01 |
4.50E+02 |
Uranium (soluble salts) |
Uranium |
- |
5.88E+02 |
Vanadium |
7440-62-2 |
- |
2.72E+01 |
Vinyl chloride |
75-01-4 |
5.93E-01 |
3.24E+02 |
Xylenes |
1330-20-7 |
- |
2.57E+02 |
Zinc |
7440-66-6 |
- |
2.94E+05 |
* - CAS Number is for Metallic Thallium
Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.
Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.
Section E1 INSTRUCTIONS FOR CALCULATING CUMULATIVE CANCER RISK AND HAZARD INDEX HYPOTHETICAL HUMAN RECEPTOR: SOIL AND/OR INDOOR AIR
Nota bene: risk-based concentration (rbc) means the calculated concentration of a chemical (or group of chemicals) in an environmental medium estimated to correspond to a fixed level of risk e.g., a target Hazard Quotient (THQ) of 1.0 for noncarcinogenic (systemic, threshold) effects or target incremental lifetime cancer risk (ILCR) of one-in-one-million (1x10 [-6) ], for a predefined hypothetical human exposure scenario. Examples of rbcs for different environmental media based on different hypothetical exposure scenarios are included in this appendix as Tables 1-3.
For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):
For a given chemical i in sample j:
For a given number of chemicals (n) in sample j, where i is the first chemical:
For given a chemical i in sample j:
For a given number of chemicals (n) in sample j, where i is the first chemical:
Example Sample-wise Calculation for Direct Contact to Soil: Residential Scenario
Analyte |
Soil Sample S01 (mg/kg) |
Benzene |
4.00E-01 |
Ethylbenzene |
6.00E+00 |
Analyte |
Sample Concentration Soil Sample S01 (mg/kg) |
Resident - Soil rbcs from Table 1 |
|
rbccancer * (mg/kg) |
rbcnoncancer * (mg/kg) |
||
Benzene |
4.00E-01 |
6.98E-01 |
1.11E+02 |
Ethylbenzene |
6.00E+00 |
3.68E+00 |
4.45E+02 |
[*] Cancer rbcs are based on target ILCR=1E [-06; ] noncancer rbcs are based on target HQ=1.0
Resident - Soil |
|||||
CANCER |
NONCANCER |
||||
Analyte |
Site Concentration Sample S01 (mg/kg) |
a rbccancer (mg/kg) |
Sample S01 ILCR (unitless) |
b rbcnoncancer (mg/kg) |
Sample S01 HQ (unitless) |
Benzene |
4.00E-01 |
6.98E-01 |
5.73E-07 |
1.11E+02 |
3.60E-02 |
Ethylbenzene |
2.00E+00 |
3.68E+00 |
1.63E-06 |
4.45E+02 |
1.35E-02 |
Sample S01 Cumulative ILCR = |
2.20E-06 |
Sample S01 Hazard Index = |
4.95E-01 |
Is 2.20E [-06 ]>1E [-06 ]?
Yes
Is 4.59E [-01 ]>1
No
For each Hypothetical Human Receptor Scenario and exposure medium (i.e., Soil, Indoor Air):
For given chemical i:
For a given number of chemicals ( n), where i is the first chemical:
For given chemical i:
For a given number of chemicals ( n), where i is the first chemical:
Example Site-wide Calculation for Direct Contact to Soil: Residential Scenario
Analyte |
Soil Exposure Point Concentration (mg/kg) |
Benzene |
4.00E-01 |
Ethylbenzene |
6.00E+00 |
Resident - Soil rbcs from Table 1 |
|||
Analyte |
Soil Concentration (mg/kg) |
rbccancer* (mg/kg) |
rbcnoncancer* (mg/kg) |
Benzene |
4.00E-01 |
6.98E-01 |
1.11E+02 |
Ethylbenzene |
6.00E+00 |
3.68E+00 |
4.45E+02 |
[* ] Cancer rbcs are based on a target ICLR=1E [-06; ] noncancer rbcs are based on target HQ=1.0
Resident - Soil |
|||||
CANCER |
NONCANCER |
||||
Analyte |
Site Exposure Point Concentration (mg/kg) |
a rbccancer (mg/kg) |
Site ILCR (unitless) |
b rbcnoncancer (mg/kg) |
Site HQ (unitless) |
Benzene |
4.00E-01 |
6.98E-01 |
5.73E-07 |
1.11E+02 |
3.60E-02 |
Ethylbenzene |
2.00E+00 |
3.68E+00 |
1.63E-06 |
4.45E+02 |
1.35E-02 |
Site Cumulative ILCR = |
2.20E-06 |
Site Hazard Index = |
4.95E-01 |
Is 2.20E [-06 ]>1E [-06 ]?
Yes
Is 4.95E [-01 ]>1
No
Because the Cumulative Site ILCR is greater than the target cancer risk for the site, further attention is warranted.
TABLE 1
SUMMARY TABLE
2019 - RESIDENT SOIL RISK-BASED CONCENTRATIONS (RBCS) (MG/KG)
INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION
Chemical Name |
CAS No. |
Resident - Soil risk-based concentations (rbcs) |
|
Cancer Target Risk=1E-6 |
Noncancer Hazard Quotient=1 |
||
Combined Routes mg/kg |
Combined Routes mg/kg |
||
Acetochlor |
34256-82-1 |
NA |
1.22E+03 |
Acetone |
67-64-1 |
NA |
4.06E+04 |
Alachlor |
15972-60-8 |
NA |
6.08E+01 |
Aldrin |
309-00-2 |
2.02E-02 |
2.10E+00 |
Aluminum |
7429-90-5 |
NA |
7.25E+04 |
Antimony |
7440-36-0 |
NA |
2.60E+01 |
Arsenic, Inorganic |
7440-38-2 |
2.32E-01 |
2.10E+01 |
Barium |
7440-39-3 |
NA |
1.12E+04 |
Benomyl |
17804-35-2 |
1.16E+02 |
7.90E+02 |
Benzene |
71-43-2 |
6.98E-01 |
1.11E+02 |
Benzo(a)pyrene (a) |
50-32-8 |
7.28E-02 |
1.72E+01 |
Beryllium |
7440-41-7 |
5.67E+02 |
3.45E+01 |
Bis(2-chloro-1-methyl ethyl)ether |
108-60-1 |
NA |
2.80E+03 |
Boron |
7440-42-8 |
NA |
1.47E+04 |
Bromate |
15541-45-4 |
5.36E-01 |
2.93E+02 |
Bromochloromethane |
74-97-5 |
NA |
1.93E+02 |
Bromoxynil |
1689-84-5 |
2.69E+00 |
9.12E+02 |
Butylbenzene, n- |
104-51-8 |
NA |
3.50E+03 |
Butylbenzene, sec- |
135-98-8 |
NA |
7.01E+03 |
Butylbenzene, tert- |
98-06-6 |
NA |
7.01E+03 |
Cadmium (food) |
7440-43-9 |
7.56E+02 |
6.86E+00 |
Carbaryl |
63-25-2 |
3.17E+02 |
6.08E+03 |
Carbon Disulfide |
75-15-0 |
NA |
6.08E+02 |
Carbon tetrachloride |
56-23-5 |
3.72E-01 |
1.30E+02 |
Chlorobenzene |
108-90-7 |
NA |
4.14E+02 |
Chromium (III) (insoluble salts) |
16065-83-1 |
NA |
4.02E+04 |
Chromium (VI) |
18540-29-9 |
9.06E-02 |
1.16E+02 |
Cobalt |
7440-48-4 |
1.51E+02 |
2.19E+01 |
Copper |
7440-50-8 |
NA |
1.04E+04 |
Di (2-ethylhexyl) phthalate |
117-81-7 |
1.98E+01 |
1.22E+03 |
Dibromochloropropane |
96-12-8 |
6.00E-03 |
6.63E+00 |
Dibromoethane, 1,2- |
106-93-4 |
2.27E-02 |
1.15E+02 |
Dichloroethane, 1,1- |
75-34-3 |
2.10E+00 |
1.40E+04 |
Dichloroethane, 1,2- |
107-06-2 |
2.85E-01 |
4.95E+01 |
Dichloroethylene, cis 1,2- |
156-59-2 |
NA |
1.40E+02 |
Dichloroethylene, trans 1,2- |
156-60-5 |
NA |
1.40E+03 |
Dichloropropane, 1,2- |
78-87-5 |
1.51E+00 |
2.63E+01 |
Dioxane, 1,4- |
123-91-1 |
2.78E+00 |
1.05E+03 |
Ethylbenzene |
100-41-4 |
3.68E+00 |
4.45E+02 |
Fluoranthene |
206-44-0 |
NA |
2.30E+03 |
Fluorene |
86-73-7 |
NA |
2.30E+03 |
Hexachlorobenzene |
118-74-1 |
1.31E-01 |
5.61E+01 |
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) |
121-82-4 |
4.60E+00 |
2.90E+02 |
Iron |
7439-89-6 |
NA |
5.13E+04 |
Isopropylbenzene (cumene) |
98-82-8 |
NA |
2.56E+02 |
Manganese (non-diet) |
7439-96-5 |
NA |
1.12E+03 |
Mercury (elemental) |
7439-97-6 |
NA |
3.13E+00 |
Methyl ethyl ketone |
78-93-3 |
NA |
1.70E+04 |
Methyl tert-butyl ether (MTBE) |
1634-04-4 |
NA |
6.49E+02 |
Molybdenum |
7439-98-7 |
NA |
3.66E+02 |
Naphthalene |
91-20-3 |
2.72E+00 |
2.24E+02 |
Nickel |
7440-02-0 |
5.23E+03 |
9.40E+02 |
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) |
2691-41-0 |
NA |
3.70E+03 |
Pentachlorophenol |
87-86-5 |
4.84E-01 |
2.37E+02 |
Pentaerythritol tetranitrate (PETN) |
78-11-5 |
NA |
1.22E+02 |
Perchlorate |
14797-73-0 |
NA |
5.13E+01 |
Perfluoroheptanoic acid (PFHpA) (b) |
375-85-9 |
NA |
1.22E+00 |
Perfluorohexane sulfonic acid (PFHxS) (b) |
355-46-4 |
NA |
1.22E+00 |
Perfluorononanoic acid (PFNA) (b) |
375-95-1 |
NA |
1.22E+00 |
Perfluorooctane sulfonic acid (PFOS) (b) |
1763-23-1 |
NA |
1.22E+00 |
Perfluorooctanoic acid (PFOA) (b) |
335-67-1 |
3.96E+00 |
1.22E+00 |
Polychlorinated biphenyls (c)(PCBs) |
1336-36-3 |
1.14E-01 |
1.13E+00 |
Propoxur (Baygon) |
114-26-1 |
7.88E+01 |
2.43E+02 |
Propyl benzene, n- |
103-65-1 |
NA |
2.53E+02 |
Selenium |
7782-49-2 |
NA |
3.66E+02 |
Silver |
7440-22-4 |
NA |
2.37E+02 |
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD) |
1746-01-6 |
2.25E-06 |
4.91E-05 |
Tetrachloroethane, 1,1,1,2- |
630-20-6 |
1.32E+00 |
2.10E+03 |
Tetrachloroethylene |
127-18-4 |
2.38E+00 |
1.13E+02 |
Thallium (soluble Thallium) |
7440-28-0 * |
NA |
7.33E-01 |
Toluene |
108-88-3 |
NA |
7.06E+02 |
Trichloroethylene (non-moa / mmoa) |
79-01-6 |
6.81E-01 |
6.21E+00 |
Trichloropropane, 1,2,3- |
96-18-4 |
3.11E-03 |
8.67E+00 |
Trimethylbenzene, 1,2,3- (d) |
526-73-8 |
NA |
2.06E+02 |
Trimethylbenzene, 1,2,4- (d) |
95-63-6 |
NA |
1.66E+02 |
Trimethylbenzene, 1,3,5- (d) |
108-67-8 |
NA |
1.44E+02 |
Trinitrotoluene, 2,4,6- (TNT) |
118-96-7 |
1.15E+01 |
3.49E+01 |
Uranium (soluble salts) |
NA |
NA |
4.40E+01 |
Vanadium |
7440-62-2 |
NA |
2.77E+00 |
Vinyl chloride |
75-01-4 |
9.83E-02 |
8.51E+01 |
Xylenes |
1330-20-7 |
NA |
2.52E+02 |
Zinc |
7440-66-6 |
NA |
2.20E+04 |
TABLE 2
SUMMARY TABLE
2019 - COMMERCIAL WORKER SOIL risk-based concentrations (rbcs) (mg/kg)
INCIDENTAL INGESTION, DERMAL CONTACT AND INHALATION
Chemical Name |
CAS No. |
Commerical Worker - Soil risk-based concentations (rbcs) |
|
Cancer Target Risk=1E-6 |
Noncancer Hazard Quotient=1 |
||
Combined Routes mg/kg |
Combined Routes mg/kg |
||
Acetochlor |
34256-82-1 |
- |
1.44E+04 |
Acetone |
67-64-1 |
- |
1.00E+05 |
Alachlor |
15972-60-8 |
- |
7.18E+02 |
Aldrin |
309-00-2 |
9.76E-02 |
2.15E+01 |
Aluminum |
7429-90-5 |
- |
9.42E+05 |
Antimony |
7440-36-0 |
- |
3.19E+02 |
Arsenic, Inorganic |
7440-38-2 |
1.41E+00 |
2.71E+02 |
Barium |
7440-39-3 |
- |
1.27E+05 |
Benomyl |
17804-35-2 |
7.01E+02 |
9.34E+03 |
Benzene |
71-43-2 |
4.19E+00 |
4.18E+02 |
Benzo(a)pyrene (a) |
50-32-8 |
1.54E+00 |
1.94E+02 |
Beryllium |
7440-41-7 |
4.63E+03 |
2.89E+02 |
Bis(2-chloro-1-methyl ethyl)ether |
108-60-1 |
- |
3.63E+04 |
Boron |
7440-42-8 |
- |
1.96E+05 |
Bromate |
15541-45-4 |
3.27E+00 |
3.92E+03 |
Bromochloromethane |
74-97-5 |
- |
5.97E+02 |
Bromoxynil |
1689-84-5 |
1.63E+01 |
1.08E+04 |
Butylbenzene, n- |
104-51-8 |
- |
5.11E+04 |
Butylbenzene, sec- |
135-98-8 |
- |
1.02E+05 |
Butylbenzene, tert- |
98-06-6 |
- |
1.02E+05 |
Cadmium (food) |
7440-43-9 |
6.18E+03 |
8.72E+01 |
Carbaryl |
63-25-2 |
1.91E+03 |
7.18E+04 |
Carbon Disulfide |
75-15-0 |
- |
6.62E+02 |
Carbon tetrachloride |
56-23-5 |
2.23E+00 |
3.59E+02 |
Chlorobenzene |
108-90-7 |
- |
7.26E+02 |
Chromium (III) (insoluble salts) |
16065-83-1 |
- |
3.60E+05 |
Chromium (VI) |
18540-29-9 |
1.75E+00 |
1.14E+03 |
Cobalt |
7440-48-4 |
1.24E+03 |
2.91E+02 |
Copper |
7440-50-8 |
- |
1.39E+05 |
Di (2-ethylhexyl) phthalate |
117-81-7 |
1.20E+02 |
1.44E+04 |
Dibromochloropropane |
96-12-8 |
6.15E-02 |
2.75E+01 |
Dibromoethane, 1,2- |
106-93-4 |
1.39E-01 |
3.49E+02 |
Dichloroethane, 1,1- |
75-34-3 |
1.26E+01 |
2.04E+05 |
Dichloroethane, 1,2- |
107-06-2 |
1.71E+00 |
1.40E+02 |
Dichloroethylene, cis 1,2- |
156-59-2 |
- |
1.81E+03 |
Dichloroethylene, trans 1,2- |
156-60-5 |
- |
1.81E+04 |
Dichloropropane, 1,2- |
78-87-5 |
9.06E+00 |
6.81E+01 |
Dioxane, 1,4- |
123-91-1 |
1.69E+01 |
4.49E+03 |
Ethylbenzene |
100-41-4 |
2.21E+01 |
4.73E+02 |
Fluoranthene |
206-44-0 |
- |
2.64E+04 |
Fluorene |
86-73-7 |
- |
2.64E+04 |
Hexachlorobenzene |
118-74-1 |
6.86E-01 |
5.74E+02 |
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) |
121-82-4 |
2.80E+01 |
3.84E+03 |
Iron |
7439-89-6 |
- |
6.86E+05 |
Isopropylbenzene (cumene) |
98-82-8 |
- |
2.64E+02 |
Manganese (non-diet) |
7439-96-5 |
- |
1.14E+04 |
Mercury (elemental) |
7439-97-6 |
- |
3.13E+00 |
Methyl ethyl ketone |
78-93-3 |
- |
2.70E+04 |
Methyl tert-butyl ether (MTBE) |
1634-04-4 |
- |
4.46E+03 |
Molybdenum |
7439-98-7 |
- |
4.90E+03 |
Naphthalene |
91-20-3 |
1.64E+01 |
6.78E+02 |
Nickel |
7440-02-0 |
4.28E+04 |
9.71E+03 |
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) |
2691-41-0 |
- |
4.98E+04 |
Pentachlorophenol |
87-86-5 |
2.90E+00 |
2.48E+03 |
Pentaerythritol tetranitrate (PETN) |
78-11-5 |
- |
1.44E+03 |
Perchlorate |
14797-73-0 |
- |
6.86E+02 |
Perfluoroheptanoic acid (PFHpA) (b) |
375-85-9 |
- |
remove |
Perfluorohexane sulfonic acid (PFHxS) (b) |
355-46-4 |
- |
1.44E+01 |
Perfluorononanoic acid (PFNA) (b) |
375-95-1 |
- |
1.44E+01 |
Perfluorooctane sulfonic acid (PFOS) (b) |
1763-23-1 |
- |
1.44E+01 |
Perfluorooctanoic acid (PFOA) (b) |
335-67-1 |
2.39E+01 |
1.44E+01 |
Polychlorinated biphenyls (PCBs) (c) |
1336-36-3 |
6.83E-01 |
1.28E+01 |
Propoxur (Baygon) |
114-26-1 |
4.76E+02 |
2.87E+03 |
Propyl benzene, n- |
103-65-1 |
- |
2.61E+02 |
Selenium |
7782-49-2 |
- |
4.90E+03 |
Silver |
7440-22-4 |
- |
2.48E+03 |
Tetrachlorodibenzo-p-dioxin, 2,3,7,8- (TCDD) |
1746-01-6 |
1.37E-05 |
6.35E-04 |
Tetrachloroethane, 1,1,1,2- |
630-20-6 |
8.00E+00 |
3.07E+04 |
Tetrachloroethylene |
127-18-4 |
1.43E+01 |
1.51E+02 |
Thallium (soluble Thallium) |
7440-28-0 * |
- |
1.96E+05 |
Toluene |
108-88-3 |
- |
7.98E+02 |
Trichloroethylene (non-moa) |
79-01-6 |
6.47E+00 |
1.86E+01 |
Trichloropropane, 1,2,3- |
96-18-4 |
7.05E-02 |
2.29E+01 |
Trimethylbenzene, 1,2,3- (d) |
526-73-8 |
- |
2.82E+02 |
Trimethylbenzene, 1,2,4- (d) |
95-63-6 |
- |
2.12E+02 |
Trimethylbenzene, 1,3,5- (d) |
108-67-8 |
- |
1.77E+02 |
Trinitrotoluene, 2,4,6- (TNT) |
118-96-7 |
7.00E+01 |
4.50E+02 |
Uranium (soluble salts) |
Uranium |
- |
5.88E+02 |
Vanadium |
7440-62-2 |
- |
2.72E+01 |
Vinyl chloride |
75-01-4 |
5.93E-01 |
3.24E+02 |
Xylenes |
1330-20-7 |
- |
2.57E+02 |
Zinc |
7440-66-6 |
- |
2.94E+05 |
TABLE 3
SUMMARY TABLE
2019 - RESIDENT AND NONRESIDENTIAL INDOOR AIR risk-based concentrations (rbcs) (5g/m [3) ]
INHALATION
Chemical Name |
CAS No. |
Indoor Air risk-based concentrations (rbcs) |
|||
Resident - Indoor Air |
Nonresidential - Indoor Air |
||||
Cancer Target Risk = 1x10-6 |
Noncancer Hazard Quotient = 1.0 |
Cancer Target Risk = 1x10-6 |
Noncancer Hazard Quotient = 1.0 |
||
Inhalation µg/m3 |
Inhalation µg/m3 |
Inhalation µg/m3 |
Inhalation µg/m3 |
||
Benzene |
71-43-2 |
0.13 |
30.00 |
1.05 |
105.12 |
Carbon tetrachloride |
56-23-5 |
0.17 |
100.00 |
1.36 |
350.40 |
Chloroethane |
75-00-3 |
-- |
10000.00 |
-- |
35040.00 |
Chloroform |
67-66-3 |
0.04 |
97.70 |
0.36 |
342.34 |
Dichloroethane, 1,1- |
75-34-3 |
0.63 |
-- |
5.11 |
-- |
Dichloroethene, 1,1- |
75-35-4 |
-- |
200.00 |
-- |
700.80 |
Ethylbenzene |
100-41-4 |
4.00E-01 |
260.00 |
3.27E+00 |
911.04 |
Mercury (elemental) |
7439-97-6 |
-- |
0.30 |
-- |
0.3 (a) |
Methylene chloride |
75-09-2 |
60.34 |
600.00 |
817.60 |
2102.40 |
Naphthalene |
91-20-3 |
0.03 |
3.00 |
0.24 |
10.51 |
Tetrachloroethylene |
127-18-4 |
0.63 |
40.00 |
5.11 |
140.16 |
Trichloroethylene |
79-01-6 |
0.20 |
0.2 (c) |
1.99 |
0.7 (b) |
Trimethylbenzene, 1,2,3- |
526-73-8 |
-- |
60 (c) |
-- |
210.24 (c) |
Trimethylbenzene, 1,2,4- |
95-63-6 |
-- |
60 (c) |
-- |
210.24 (c) |
Trimethylbenzene, 1,3,5- |
108-67-8 |
-- |
60 (c) |
-- |
210.24 (c) |
Vinyl chloride |
75-01-4 |
0.11 |
100.00 |
1.86 (d) |
350.40 |
* - CAS Number is for Metallic Thallium
Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.
Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.
All cancer-based soil inhalation screening values were less than respective Csat thus no substitutions.
Noncancer-based soil inhalation screening value above respective Csat thus Csat substitiouion employed for the following:
Acetone, Carbon Disulfide, Ethylbenzene, Isopropylbenzene (cumene), Mercury (elemental), Methyl ethyl ketone, Methyl tert-butyl ether, n-Propyl benzene, Tetrachloroethylene, Toluene, Trimethyl benzenes, Xylenes.
* - CAS Number is for Metallic Thallium
Groundwater temperature of 150C used in derivation of volatiziation factors with May 2018 Regional Screening Level Calculator.
Csat substitution used if soil inhalation screening value greater than Csat. Csats derived using May 2018 Regional Screening Level Calculator.
Appendix F Toxicity Equivalence Factors
Some chemicals are members of the same family or group and have been shown to exhibit similar toxicological properties; however, each chemical may differ in the degree of toxicity (EPA, 2019). In some such instances, a toxicity (sometimes referred to as toxic) equivalency factor (TEF) or relative potency factor (RPF) must be applied to convert the reported concentration of each member of the group to a toxicity (sometimes referred to as toxic) equivalent concentration (TEQ) or to toxic equivalents (TE) relative to the toxicity of the index chemical for the group. The index chemical is assigned a TEF or RPF of 1. Total TEQ or TE can be compared to risk-based values derived for the index chemical or assessed using as any other single chemical in a quantitative risk assessment.
Dioxins, Furans and dioxin-like Polychlorinated Biphenyls (PCBs)
The index chemical for this group is 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). As of this writing, Health recommends that the 2005 World Health Organization Toxic Equivalency Factors (Van den Berg et al., 2006) be employed in the evaluation of dioxins, furans and dioxin-like PCBs. These values are also presented in the May 2013 U.S. EPA fact sheet, "Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites" which references the 2010 U.S. EPA report, "Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds" (EPA, 2019). TEFs for Di-ortho PCBs may be obtained from Ahlborg, U.G. et al., 1994 (EPA, 2019). TEFs may be applied to the ingestion, dermal (see EPA, 2004) or inhalation routes of exposure and adjusted values may be used in the assessment of both cancer and noncarcinogenic effects (EPA, 2013). The sum of adjusted concentrations is often referred to as 2,3,7,8-TCDD TEQ.
Dioxin Toxicity Equivalence Factors (EPA, 2019)
CAS Registry Number |
Compound |
2,3,7,8-TCDD Toxicity Equivalence Factor |
Chlorinated dibenzo-p-dioxins |
||
1746-01-6 |
2,3,7,8-TCDD |
1 |
40321-76-4 |
1,2,3,7,8-PeCDD |
1 |
39227-28-6 |
1,2,3,4,7,8-HxCDD |
0.1 |
72918-21-9 |
1,2,3,6,7,8-HxCDD |
0.1 |
57653-85-7 |
1,2,3,7,8,9-HxCDD |
0.1 |
35822-46-9 |
1,2,3,4,6,7,8-HpCDD |
0.01 |
3268-87-9 |
OCDD |
0.0003 |
Chlorinated dibenzofurans |
||
51207-31-9 |
2,3,7,8-TCDF |
0.1 |
57117-41-6 |
1,2,3,7,8-PeCDF |
0.03 |
57117-31-4 |
2,3,4,7,8-PeCDF |
0.3 |
70648-26-9 |
1,2,3,4,7,8-HxCDF |
0.1 |
57117-44-9 |
1,2,3,6,7,8-HxCDF |
0.1 |
72918-21-9 |
1,2,3,7,8,9-HxCDF |
0.1 |
60851-34-5 |
2,3,4,6,7,8-HxCDF |
0.1 |
35822-46-9 |
1,2,3,4,6,7,8-HpCDF |
0.01 |
55673-89-7 |
1,2,3,4,7,8,9-HpCDF |
0.01 |
39001-02-0 |
OCDF |
0.0003 |
PCBs |
|||
IUPAC No. |
Structure |
||
Non- ortho |
|||
32598-13-3 |
77 |
3,3',4,4'-TetraCB |
0.0001 |
70362-50-4 |
81 |
3,4,4',5-TetraCB |
0.0003 |
57465-28-8 |
126 |
3,3',4,4',5-PeCB |
0.1 |
32774-16-6 |
169 |
3,3',4,4',5,5'-HxCB |
0.03 |
Mono- ortho |
|||
32598-14-4 |
105 |
2,3,3',4,4'-PeCB |
0.00003 |
74472-37-0 |
114 |
2,3,4,4',5-PeCB |
0.00003 |
31508-00-6 |
118 |
2,3',4,4',5-PeCB |
0.00003 |
65510-44-3 |
123 |
2',3,4,4',5-PeCB |
0.00003 |
38380-08-4 |
156 |
2,3,3',4,4',5-HxCB |
0.00003 |
69782-90-7 |
157 |
2,3,3',4,4',5'-HxCB |
0.00003 |
52663-72-6 |
167 |
2,3',4,4',5,5'-HxCB |
0.00003 |
39635-31-9 |
189 |
2,3,3',4,4',5,5'-HpCB |
0.00003 |
Di- ortho* |
|||
35065-30-6 |
170 |
2,2',3,3',4,4',5-HpCB |
0.0001 |
35065-29-3 |
180 |
2,2',3,4,4',5,5'-HpCB |
0.00001 |
[* ] Di-ortho values come from Ahlborg, U.g., et al (1994), which are the WHO 1994 values from Toxic equivalency factors for dioxin-like PCBs: Report on WHO-ECEH and IPCS consultation. December 1993. Chemosphere Volume 28, Issue 6. March 1994. Pages 1049-1067.
Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAH)
Benzo(a)pyrene (B(a)P) is the index chemical for this group of compounds. As of this writing, Health recommends that the following RPFs (EPA, 1993) be employed in the evaluation of cPAH only with respect to carcinogenicity. The sum of adjusted concentrations is referred to as Benzo(a)pyrene toxic equivalents i.e., B(a)P-TE and may be used in the assessment of ingestion, dermal (see EPA, 2004) or inhalation exposure.
Relative Potency Factors for Carcinogenic Polycyclic Aromatic Hydrocarbons
CAS Registry Number |
Compound |
Benzo(a)pyrene Relative Potency Factor |
50-32-8 |
Benzo(a)pyrene |
1 |
56-55-3 |
Benzo(a)anthracene |
0.1 |
205-99-2 |
Benzo(b)fluoranthene |
0.1 |
207-08-9 |
Benzo(k)fluoranthene |
0.01 |
218-01-9 |
Chrysene |
0.001 |
53-70-3 |
Dibenzo(a,h)anthracene |
1 |
193-39-5 |
Indeno(1,2,3cd)pyrene |
0.1 |
References
EPA, 1993. Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons. U.S. Environmental Protection Agency. Research Triangle Park, N.C. EPA/600/R-93/089, July 1993.
EPA, 2004. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. OSWER 9285.7- 02EP.July 2004.
EPA, 2013. Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites. United States Environmental Protection Agency. May 2013.
EPA, 2019. United States Environmental Protection Agency. Regional Screening Levels for Chemical Contaminants at Superfund Sites. User's Guide. November 2018 edition. (accessed February 27, 2019).
Van den Berg et al., 2006. The 2005 World Health Organization re-evaluation of human and mammalian toxic equivalency factors for dioxins and dioxin-like compounds. Toxicol Sci 93(2):223-241.
Section F1 TOXICITY EQUIVALENCE FACTORS AND RELATIVE POTENCY FACTORS
Some chemicals are members of the same family or group and have been shown to exhibit similar toxicological properties; however, each chemical may differ in the degree of toxicity (EPA, 2019). In some such instances, a toxicity (sometimes referred to as toxic) equivalency factor (TEF) or relative potency factor (RPF) must be applied to convert the reported concentration of each member of the group to a toxicity (sometimes referred to as toxic) equivalent concentration (TEQ) or to toxic equivalents (TE) relative to the toxicity of the index chemical for the group. The index chemical is assigned a TEF or RPF of 1. Total TEQ or TE can be compared to risk-based values derived for the index chemical or assessed using as any other single chemical in a quantitative risk assessment.
Dioxins, Furans and dioxin-like Polychlorinated Biphenyls (PCBs)
The index chemical for this group is 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). As of this writing, Health recommends that the 2005 World Health Organization Toxic Equivalency Factors (Van den Berg et al., 2006) be employed in the evaluation of dioxins, furans and dioxin-like PCBs. These values are also presented in the May 2013 U.S. EPA fact sheet, "Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites" which references the 2010 U.S. EPA report, "Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds" (EPA, 2019). TEFs for Di-ortho PCBs may be obtained from Ahlborg, U.G. et al., 1994 (EPA, 2019). TEFs may be applied to the ingestion, dermal (see EPA, 2004) or inhalation routes of exposure and adjusted values may be used in the assessment of both cancer and noncarcinogenic effects (EPA, 2013). The sum of adjusted concentrations is often referred to as 2,3,7,8-TCDD TEQ.
Dioxin Toxicity Equivalence Factors (EPA, 2019)
CAS Registry Number |
Compound |
2,3,7,8-TCDD Toxicity Equivalence Factor |
Chlorinated dibenzo-p-dioxins |
||
1746-01-6 |
2,3,7,8-TCDD |
1 |
40321-76-4 |
1,2,3,7,8-PeCDD |
1 |
39227-28-6 |
1,2,3,4,7,8-HxCDD |
0.1 |
72918-21-9 |
1,2,3,6,7,8-HxCDD |
0.1 |
57653-85-7 |
1,2,3,7,8,9-HxCDD |
0.1 |
35822-46-9 |
1,2,3,4,6,7,8-HpCDD |
0.01 |
3268-87-9 |
OCDD |
0.0003 |
Chlorinated dibenzofurans |
||
51207-31-9 |
2,3,7,8-TCDF |
0.1 |
57117-41-6 |
1,2,3,7,8-PeCDF |
0.03 |
57117-31-4 |
2,3,4,7,8-PeCDF |
0.3 |
70648-26-9 |
1,2,3,4,7,8-HxCDF |
0.1 |
57117-44-9 |
1,2,3,6,7,8-HxCDF |
0.1 |
72918-21-9 |
1,2,3,7,8,9-HxCDF |
0.1 |
60851-34-5 |
2,3,4,6,7,8-HxCDF |
0.1 |
35822-46-9 |
1,2,3,4,6,7,8-HpCDF |
0.01 |
55673-89-7 |
1,2,3,4,7,8,9-HpCDF |
0.01 |
39001-02-0 |
OCDF |
0.0003 |
PCBs |
|||
IUPAC No. |
Structure |
||
Non- ortho |
|||
32598-13-3 |
77 |
3,3',4,4'-TetraCB |
0.0001 |
70362-50-4 |
81 |
3,4,4',5-TetraCB |
0.0003 |
57465-28-8 |
126 |
3,3',4,4',5-PeCB |
0.1 |
32774-16-6 |
169 |
3,3',4,4',5,5'-HxCB |
0.03 |
Mono- ortho |
|||
32598-14-4 |
105 |
2,3,3',4,4'-PeCB |
0.00003 |
74472-37-0 |
114 |
2,3,4,4',5-PeCB |
0.00003 |
31508-00-6 |
118 |
2,3',4,4',5-PeCB |
0.00003 |
65510-44-3 |
123 |
2',3,4,4',5-PeCB |
0.00003 |
38380-08-4 |
156 |
2,3,3',4,4',5-HxCB |
0.00003 |
69782-90-7 |
157 |
2,3,3',4,4',5'-HxCB |
0.00003 |
52663-72-6 |
167 |
2,3',4,4',5,5'-HxCB |
0.00003 |
39635-31-9 |
189 |
2,3,3',4,4',5,5'-HpCB |
0.00003 |
Di- ortho* |
|||
35065-30-6 |
170 |
2,2',3,3',4,4',5-HpCB |
0.0001 |
35065-29-3 |
180 |
2,2',3,4,4',5,5'-HpCB |
0.00001 |
[* ] Di-ortho values come from Ahlborg, U.g., et al (1994), which are the WHO 1994 values from Toxic equivalency factors for dioxin-like PCBs: Report on WHO-ECEH and IPCS consultation. December 1993. Chemosphere Volume 28, Issue 6. March 1994. Pages 1049-1067.
Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAH)
Benzo(a)pyrene (B(a)P) is the index chemical for this group of compounds. As of this writing, Health recommends that the following RPFs (EPA, 1993) be employed in the evaluation of cPAH only with respect to carcinogenicity. The sum of adjusted concentrations is referred to as Benzo(a)pyrene toxic equivalents i.e., B(a)P-TE and may be used in the assessment of ingestion, dermal (see EPA, 2004) or inhalation exposure.
Relative Potency Factors for Carcinogenic Polycyclic Aromatic Hydrocarbons
CAS Registry Number |
Compound |
Benzo(a)pyrene Relative Potency Factor |
50-32-8 |
Benzo(a)pyrene |
1 |
56-55-3 |
Benzo(a)anthracene |
0.1 |
205-99-2 |
Benzo(b)fluoranthene |
0.1 |
207-08-9 |
Benzo(k)fluoranthene |
0.01 |
218-01-9 |
Chrysene |
0.001 |
53-70-3 |
Dibenzo(a,h)anthracene |
1 |
193-39-5 |
Indeno(1,2,3cd)pyrene |
0.1 |
References
EPA, 1993. Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons. U.S. Environmental Protection Agency. Research Triangle Park, N.C. EPA/600/R-93/089, July 1993.
EPA, 2004. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. OSWER 9285.7- 02EP.July 2004.
EPA, 2013. Use of Dioxin TEFs in Calculating Dioxin TEQs at CERCLA and RCRA Sites. United States Environmental Protection Agency. May 2013.
EPA, 2019. United States Environmental Protection Agency. Regional Screening Levels for Chemical Contaminants at Superfund Sites. User's Guide. November 2018 edition. (accessed February 27, 2019).
Van den Berg et al., 2006. The 2005 World Health Organization re-evaluation of human and mammalian toxic equivalency factors for dioxins and dioxin-like compounds. Toxicol Sci 93(2):223-241.