Reference Dose (Non-cancer risk) Start with the NOAEL(mg/kg BW/day) Calculate a reference dose(RfD): RfD=NOAEL UF UF:10X for Interspecies 10X for Intraspecies Other(as needed) Uncertainty Factors OSU 0regomstate Reference Dose (Non-cancer risk) • Start with the NOAEL (mg/kg BW/day) • Calculate a reference dose (RfD): RfD = UF NOAEL UF: 10X for Interspecies 10X for Intraspecies Other (as needed) Uncertainty Factors