1,1'-Biphenyl, 2,3',4,4'-tetrachloro- (9CI) 2,3',4,4'-TETRACHLOROBIPHENYL 2,3',4,4'-Tetrachloro-1,1'-biphenyl 2,4,3',4'-TCB 2,4,3',4'-Tetrachlorobiphenyl 3,4,2',4'-Tetrachlorobiphenyl 32598-10-0 BRN 2371385 Biphenyl, 2,3',4,4'-tetrachloro- PCB 66