Pennsylvania Code (Last Updated: April 5, 2016) |
Title 25. ENVIRONMENTAL PROTECTION |
PART I. Department of Environmental Protection |
Subpart D. Environmental Health and Safety |
Article VI. General Health and Safety |
Chapter 250. Administration of Land Recycling Program |
SubChapter C. STATEWIDE HEALTH STANDARDS |
Section 250.306. Ingestion numeric values
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(a) For a regulated substance which is a systemic toxicant, the ingestion numeric value for that substance was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation: {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorMSC µ= {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorTHQ x RfD{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element erroro x BW x AT {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errornc x 365 days/year {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorAbs x EF x ED x IngR x CF
(b) For a regulated substance which is a carcinogen, the ingestion numeric value for that substance was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equations:
(1) For regulated substances not identified as a mutagen in § 250.301(b) (relating to scope): {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorMSC µ= {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorTR x AT{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorc x 365 days/year {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorCSF{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element erroro x Abs x EF x IFadj x CF
(2) For regulated substances identified as a mutagen, except for vinyl chloride, in § 250.301(b): {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorMSC µ= {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorTR x AT{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorc x 365 days/year {PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element errorCSF{PaCodeERROR}Unknown Element error{PaCodeERROR}Unknown Element erroro x Abs x EF x AIFadj x CF
(3) For vinyl chloride:
MSC = TR
[CSFo x Abs x EF x IFadj x CF / (ATc x 365 days/year)] +
(CSFo x Abs x IRc x CF/BWc)
(c) For a regulated substance that has both an oral reference dose and an oral cancer slope factor, the ingestion numeric value is the lower of the two numbers as calculated by the equations in subsections (a) and (b).
(d) The default exposure assumptions used to calculate the ingestion numeric values are as follows:
Residential Nonresidential Term Systemic1 Carcinogens2,6 (Onsite Worker) THQ Target Hazard Quotient 1 N/A 1 RfDo Oral Reference Dose (mg/kg-day) Chemical-specific N/A Chemical-specific BW Body Weight (kg) Soil Groundwater 15
70N/A
70
70ATnc Averaging Time for systemic toxicants (yr) Soil Groundwater
6
30
N/A
N/A
25
25Abs Absorption (unitless)3 1 1 1 EF Exposure Frequency (d/yr) Soil Groundwater
250
350
250
350
180
250ED Exposure Duration (yr) Soil Groundwater 6
30
N/A
N/A
25
25IngR Ingestion Rate Soil (mg/day) GW (L/day)
100
2
N/A
N/A
50
1(Footnotes on next page) CF Conversion Factor Soil (kg/mg) GW (unitless)
1 x 10-6
1
1 x 10-6
1
1 x 10-6
1TR Target Risk N/A 1 x 10-5 1 x 10-5 CSFO Oral Cancer Slope Factor (mg/kg-day)-1 N/A Chemical-specific Chemical-specific ATC Averaging Time for carcinogens (yr) N/A 70 70 Ifadj4 Ingestion Factor Soil (mg-yr/kg-day) GW (L-yr/kg-day) N/A
57.1
1.1
17.9
0.4AIFadj5 Combined Age-Dependent Adjustment Factor and Ingestion Factor Soil (mg-yr/kg-day) GW (L-yr/kg-day) N/A 245
3.39N/A Notes: 1Residential exposure to noncarcinogens is based on childhood (ages 1-6) exposure for soil, and adult exposure for groundwater, consistent with USEPA (1991). 2Residential exposure to carcinogens is based on combined childhood and adult exposure.3The oral absorption factor takes into account absorption and bioavailability. In cases where the oral RfD or CSF is based on administered oral dose, the absorption factor would be limited to bioavailability. The default value is 1. 4The Ingestion Factor for the residential scenario is calculated using the equation Ifadj = EDc x IRc/BWc + EDa x IRa/Bwa, where EDc = 6 yr, IRc = 100 mg/day for soils and 1 L/day for groundwater, BWc = 15 kg, EDa = 24 yr, IRa = 50 mg/day for soils and 2 L/day for groundwater, and BWa = 70 kg. The ingestion factor for the nonresidential scenario is calculated using the equation Ifadj = ED x IR/BW, where ED = 25 yr, IR = 50 mg/day for soils and 1 L/day for groundwater, and BW = 70 kg. 5The Combined Age-Dependent Adjustment Factor and Ingestion Factor (AIFadj) for the residential scenario is calculated using the equation AIFadj = [(ADAF2 x ED2) + (ADAF2-6 x ED 2-6)] x IRc / BWc + [(ADAF6-16 x ED6-16) + (ADAF16 x ED6-16)] x IRa / BWa, where ADAF2 = 10, ED 2 = 2 yr, ADAF2-6 = 3, ED2-6 = 4 yr, IRc = 100mg/day for soils and 1 L/day for groundwater, BWc = 15 kg, ADAF6-16 = 3, ED6-16 = 10 yr, ADAF16 = 1, ED16 = 14 yr, IRa = 50 mg/day for soils and 2 L/day for groundwater, and BWa = 70 kg.6For the equation to calculate the vinyl chloride residential MSC based on the carcinogenic effect, IRc = 100 mg/day for soils and 1 L/day for groundwater, BWc = 15 kg.
(e) The residential ingestion numeric value for lead in soil was developed using the Uptake Biokinetic (UBK) Model for Lead (version 0.4) developed by the EPA (U. S. Environmental Protection Agency. (1990). Uptake Biokinetic (UBK) Model for Lead (version 0.4). U. S. EPA/ECAO. August 1990, in lieu of the algorithms presented in subsections (a) and (b). Default input values are identified in Appendix A, Table 7. Because the UBK model is applicable only to children, the nonresidential ingestion numeric value was calculated according to the method developed by the Society for Environmental Geochemistry and Health (Wixson, B. G. (1991)). The Society for Environmental Geochemistry and Health (SEGH) Task Force Approach to the Assessment of Lead in Soil. Trace Substances in Environmental Health. (11-20), using the following equations:
Table 7 identifies each of the variables in this equation.
The provisions of this § 250.306 amended January 7, 2011, effective January 8, 2011, 41 Pa.B. 230; corrected March 19, 2011, effective March 5, 2011, 41 Pa.B. 1458; corrected May 16, 2014, effective March 5, 2011, 44 Pa.B. 2975. Immediately preceding text appears at serial pages (356272) to (356274).
Notation
The provisions of this § 250.306 issued under sections 104(a) and 303(a) of the Land Recycling and Environmental Remediation Standards Act (35 P. S. § § 6026.104(a) and 6026.303(a)).
This section cited in 25 Pa. Code § 250.304 (relating to MSCs for groundwater); 25 Pa. Code § 250.305 (relating to MSCs for soil); and 25 Pa. Code § 250.310 (relating to minimum threshold MSCs).