New Jersey Administrative Code
Title 7 - ENVIRONMENTAL PROTECTION
Chapter 26D - REMEDIATION STANDARDS
Appendix 2
DEVELOPMENT OF SOIL REMEDIATION STANDARDS FOR THE INGESTION-DERMAL EXPOSURE PATHWAY
This appendix describes the procedures and equations used by the Department to develop the soil remediation standards for the ingestion-dermal exposure pathway as contained in N.J.A.C. 7:26D Appendix 1 Tables 1 and 2. This appendix is also used to develop interim soil remediation standards for the ingestion-dermal exposure pathway pursuant to N.J.A.C. 7:26D-6 and for updating soil remediation standards for the ingestion-dermal exposure pathway pursuant to N.J.A.C. 7:26D-7.
If the calculated soil criterion for a contaminant for the ingestion-dermal exposure pathway is greater than one million mg/kg, a soil remediation standard for the ingestion-dermal exposure pathway for that contaminant does not apply.
If the calculated soil criterion for a contaminant for the ingestion-dermal exposure pathway is less than the reporting limit for that contaminant, the soil remediation standard for the ingestion-dermal exposure pathway for that contaminant defaults to the soil reporting limit.
Equations 1 through 4 below are derived from the USEPA, Regional Screening Levels (RSLs)--Equations (November 2018). A detailed explanation of the derivation of Equations 1 through 4 is contained at N.J.A.C. 7:26D Appendix 12.
Equation 1--Residential Carcinogenic Ingestion-Dermal Human Health-Based Criteria
| Parameter | Definition | Units | Default |
| IDc | Carcinogenic ingestion-dermal human health-based criterion | mg/kg | Chemical specific |
| TR | Target cancer risk | unitless | 1 x 10-6 |
| AT | Averaging time | days/year | 365 |
| LT | Lifetime | years | 70 |
| CSFo | Oral cancer slope factor | (mg/kg-day)- | 1 Chemical specific |
| IFSadj | Age-adjusted soil ingestion rate | mg/kg | 36,750 |
| CSFD | Dermal cancer slope factor | (mg/kg-day)- | 1 Chemical specific |
| DFSadj | Age-adjusted soil dermal contact factor | mg/kg | 103,390 |
| ABSd | Dermal absorption fraction | unitless | Chemical specific |
Where:
| Parameter | Definition | Units | Default |
| IFSadj | Age-adjusted soil ingestion rate | mg/kg | 36,750 |
| EFc | Exposure frequency-child | days/year | 350 |
| EFa | Exposure frequency-adult | days/year | 350 |
| EDc | Exposure duration-child | years | 6 |
| EDa | Exposure duration-adult | years | 20 |
| IRc | Soil ingestion rate-child | mg/day | 200 |
| IRa | Soil ingestion rate-adult | mg/day | 100 |
| BWc | Body weight-child | kg | 15 |
| BWa | Body weight-adult | kg | 80 |
Where:
| Parameter | Definition | Units | Default |
| DFSadj | Age-adjusted soil dermal contact factor | mg/kg | 103,390 |
| EFc | Exposure frequency-child | days/year | 350 |
| EFa | Exposure frequency-adult | days/year | 350 |
| EDc | Exposure duration-child | years | 6 |
| EDa | Exposure duration-adult | years | 20 |
| SAc | Skin surface area-child | cm2/day | 2,373 |
| SAa | Skin surface area-adult | cm2/day | 6,032 |
| AFc | Soil adherence factor-child | mg/cm2 | 0.2 |
| AFa | Soil adherence factor-adult | mg/cm2 | 0.07 |
| BWc | Body weight-child | kg | 15 |
| BWa | Body weight-adult | kg | 80 |
Where:
| Parameter | Definition | Units | Default |
| CSFD | Dermal cancer slope factor | (mg/kg-day)-1 | Chemical specific |
| CSFO | Oral cancer slope factor | (mg/kg-day)-1 | Chemical specific |
| GIABS | Gastro-intestinal absorption fraction | unitless | Chemical specific |
Equation 2--Residential Noncarcinogenic Ingestion-Dermal Human Health-Based Criteria
| Parameter | Definition | Units | Default |
| IDnc | Noncarcinogenic ingestion-dermal human health-based criterion | mg/kg | Chemical specific |
| THQ | Target hazard quotient | unitless | 1 |
| AT | Averaging time | days/year | 365 |
| ED | Exposure duration | years | 6 |
| BW | Body weight-child | kg | 15 |
| EF | Exposure frequency | days/year | 350 |
| RfDO | Oral reference dose | mg/kg-day | Chemical specific |
| IR | Soil ingestion rate-child | mg/day | 200 |
| RfDD | Dermal reference dose | mg/kg-day | Chemical specific |
| SA | Skin surface area-child | cm2/day | 2,373 |
| AF | Soil adherence factor-child | mg/cm2 | 0.2 |
| ABSd | Dermal absorption fraction | unitless | Chemical specific |
Where:
| Parameter | Definition | Units | Default |
| RfDD | Dermal reference dose | mg/kg-day | Chemical specific |
| RfDO | Oral reference dose | mg/kg-day | Chemical specific |
| GIABS | Gastro-intestinal absorption fraction | unitless | Chemical specific |
Equation 3--Nonresidential Carcinogenic Ingestion-Dermal Human Health-Based Criteria
| Parameter | Definition | Units | Default |
| IDc | Carcinogenic ingestion-dermal human health-based criterion | mg/kg | Chemical specific |
| TR | Target cancer risk | unitless | 1 x 10-6 |
| AT | Averaging time | days/year | 365 |
| LT | Lifetime | years | 70 |
| BW | Body weight - adult | kg | 80 |
| EF | Exposure frequency-outdoor worker | days/year | 225 |
| ED | Exposure duration | years | 25 |
| CSFo | Oral cancer slope factor | (mg/kg-day)-1 Chemical specific | |
| IR | Soil ingestion rate-outdoor worker | mg/day | 100 |
| CSFD | Dermal cancer slope factor | (mg/kg-day)-1 Chemical specific | |
| SA | Skin surface area-worker | cm2/day | 3,527 |
| AF | Soil adherence factor-worker | mg/cm2 | 0.12 |
| ABSd | Dermal absorption fraction | unitless | Chemical specific |
Where:
| Parameter | Definition | Units | Default |
| CSFD | Dermal cancer slope factor | (mg/kg-day)-1 | Chemical specific |
| CSFO | Oral cancer slope factor | (mg/kg-day)-1 | Chemical specific |
| GIABS | Gastro-intestinal absorption fraction | unitless | Chemical specific |
Equation 4--Nonresidential Noncarcinogenic Ingestion-Dermal Human Health-Based Criteria
| Parameter | Definition | Units | Default |
| IDnc | Noncarcinogenic ingestion-dermal human health-based criterion | mg/kg | Chemical specific |
| THQ | Target hazard quotient | unitless | 1 |
| AT | Averaging time | days/year | 365 |
| ED | Exposure duration | years | 25 |
| BW | Body weight-adult | kg | 80 |
| EF | Exposure frequency- outdoor worker | days/year | 225 |
| RfDO | Oral reference dose | mg/kg-day | Chemical specific |
| IR | Soil ingestion rate- outdoor worker | mg/day | 100 |
| RfDD | Dermal reference dose | mg/kg-day Chemical specific | Chemical specific |
| SA | Skin surface area- worker | cm2/day | 3,527 |
| AF | Soil adherence factor-worker | mg/cm2 | 0.12 |
| ABSd | Dermal absorption fraction | unitless | Chemical specific |
Where:
| Parameter | Definition | Units | Default |
| RfDD | Dermal reference dose | mg/kg-day | Chemical specific |
| RfDO | Oral reference dose | mg/kg-day | Chemical specific |
| GIABS | Gastro-intestinal absorption fraction | unitless | Chemical specific |
Equation 5--Residential and Nonresidential Noncarcinogenic Ingestion-Dermal Human Health-Based Criteria for EPH
| Parameter | Definition | Units | Default |
| IDnc | Noncarcinogenic soil criterion for the ingestion-dermal exposure pathway | mg/kg | Chemical specific |
| THQ | Target hazard quotient | unitless | 1 |
| f' | Equivalent carbon weight fraction | unitless | Chemical specific |
| ECFV | Equivalent carbon fraction value | mg/kg | Chemical specific |
IDnc is the noncarcinogenic soil criterion for the ingestion-dermal exposure pathway for total EPH for the
EPH composition established by the eight equivalent carbon (EC) range fractions. This equation was used to calculate a single numeric total EPH soil criterion for EPH (Category 1). This equation will be used to calculate a sample-specific total EPH soil criterion for all EPH (Category 2) using the Department's online EPH Calculator.
The equivalent carbon fraction value (ECFV) equation and default input variables are the same as used to calculate the noncarcinogenic soil criteria for the specific individual contaminants for the ingestion-dermal absorption exposure pathway shown in Equations 2 and 4. That is, each EC range is treated as if it is a single contaminant.
