Reference Dose relative to NOAEL 8 6 0 NOAEL(the "threshold") 0.03 0.3 6 8 DOSE RfD=NOAEL UF 3=0.03 mg/kg/day RfD=-10x10 OSU 0re9onsa邮Reference Dose relative to NOAEL DOSE 0 2468 RESPONSE 2 0 4 6 8 NOAEL (the "threshold") 0.03 0.3 RfD = UF NOAEL RfD = 10 x10 3 = 0.03 mg/kg/day