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*Awe .s <br /> Hazard Ouotient Equation for Soil <br /> From the Department of Toxic Substances Control(DTSC)Preliminary Endangerment Assessment Guidance <br /> Manual(PEA Guidance Manual)(DTSC, 1994),the HQ for copper is calculated using the following equation: <br /> r <br /> HQ 1 xCsx[IRS xEFxEDxl0-6kg/mg] + I xCsx[SAxAFxABSxEFxEDxl0�kg/mg]1 <br /> —[RJD° BWxATx365daylyear ] [RJD. BWxATx365day1year JJ <br /> r <br /> (equation 1) <br /> Where: <br /> ` RJD° =oral reference dose,in mg/kg-day <br /> Cs =concentration in soil,mg/kg <br /> IR, =incidental soil ingestion rate,mg/day <br /> ` EF =exposure frequency for soil ingestion,days per year <br /> ED =exposure duration,years <br /> BW =body weight,kilograms <br /> ` AT =averaging time,years 2 <br /> SA =skin surface area exposed,M <br /> AF =soil to skin adherence factor, mg/cm2 <br /> ABS =absorption fraction,dimensionless <br /> r <br /> For the adult industrial worker, <br /> IR, = 100 mg/day(DTSC, 1994) <br /> EF =350 days per year(5 days a week for 50 weeks a year)(DTSC, 1994) <br /> ED =24 years(DTSC, 1994) <br /> BW =70 kilograms(DTSC, 1994) <br /> AT =70 years(DTSC, 1994) <br /> SA =5,800 cm2(DTSC, 1994) <br /> AF = 1 mg/cm2 (DTSC, 1994) <br /> r <br /> Substituting the above values into equation 1,the HQ for the adult industrial worker reduces to: <br /> � 1 <br /> HQ=� Cs x(4.697x10-7)]+f CsxABSx(2.724x10-5) (equation2) <br /> RfD° L RJD° <br /> r <br /> Hazard Quotient for a Specific Concentration of Copper <br /> For copper, <br /> ABS =0.01 (DTSC, 1994) <br /> RJD° =4.0 x 10'2 mg/kg-day(EPA Region D:, 2002) <br /> r <br /> Given a copper concentration of 370 mg/kg(Cs), and substituting the constants for copper into equation 2, <br /> the resulting HQ for the adult industrial worker would be 0.0069,or approximately 0.007. <br /> r <br /> r <br />