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Human Health Screening Evaluation <br /> Surland Homes—Bridle Creek February 12,2009 <br /> ' Riskait= inhalation cancer risk from indirect soil exposure <br /> SH =inhalation cancer slope factor, (mg/kg-day)_t <br /> ' Ca=concentration in air, mg/m3 <br /> As discussed in section 5.3, the value for Ca was estimated using equations presented in PEA <br /> ' Guidance Manual Figures 2.5, 2.6, and 2.7 for volatile organic compounds (VOCs), and Figure <br /> 2.8 for non-VOCs. <br /> ' Table 9 shows the residential inhalation cancer risk calculations for potential exposure to soil at <br /> the site. Potential cancer risks were estimated for BTEX, PAHs, and metals, and then summed <br /> among chemicals for inhalation exposures. <br /> The cancer risks for oral and dermal exposures (Table 8) were then summed with the risks for <br /> inhalation exposures (Table 9) to estimate the cancer risks across residential exposure routes for <br /> ' soil. Table 10 shows the sum of residential oral, dermal, and inhalation cancer risks for soil. <br /> 5.2 RESIDENTIAL NON-CANCER HEALTH HAZARDS <br /> ' For potential on-site residential receptors, the calculation of oral, dermal, and inhalation health <br /> hazards from exposure to on-site soils were calculated using the following equations: <br /> Oral and Dermal Hazards for Soil (PEA Guidance Manual, Figure 2.3): <br /> Hazardsoii = ([CS/RfDo] x [1.28E-051) + ([Cs/RfDo] x [1.28E-04] x ABS) <br /> tWhere: <br /> Hazardso;c= oral and dermal non-cancer hazards from direct soil exposure <br /> ' Cs =concentration in soil, mg/kg <br /> RfDo = oral reference dose, in units of mg/kg-day <br /> ' ABS = dermal absorption fraction, dimensionless <br /> Table 11 shows the residential oral and dermal hazard calculations for potential exposure to soil <br /> ' at the site. Potential non-cancer hazards were estimated for BTEX, PAHs, and metals, and then <br /> summed among chemicals for oral and dermal exposures. <br /> ' Inhalation Non-Cancer Hazard for Air (PEA Guidance Manual, Figure 2.4): <br /> Hazard,,ir= (Ca/RfDi) x 0.639 <br /> ' Where: <br /> Hazard,;,= inhalation non-cancer hazard from indirect soil exposure <br /> tRfDi = the inhalation reference dose, mg/kg-day <br /> Ca= concentration in air, mg/m3 <br /> From Science to Solutions <br />