Precition and Recovery (PAR) Standard Solution Dioxin-like PCBs each in 20ng/mL solution in n-nonane; unit: 1x1mL Chiron No. Dioxin-like PCBs PCB No. CAS No. 2006.12 3,3’4,4’-TetraCB PCB-77 [32598-13-3] 2007.12 3,4,4’,5-TetraCB PCB-81 [703