Also Called: 2,3',4,4'-TETRACHLOROBIPHENYL (PCB-66);PCB 66;2,3',4,4'-Tetrachlorobiphenyl;Polychlorinated biphenyls (PCBs);2,3’4,4’-tetrachlorobiphenyl;1,2-dichloro-4-(2,4-dichlorophenyl)benzene;2,4,3',4'-PCB;1,1'-Biphenyl, 2,3',4,4'-tetrachloro-;2,3',4,4'-Tetrachlorobiphenyl (PCB 66)