(1,1'-Biphenyl)-3,4-diol, 2,2',4',6,6'-pentachloro- 2,2',4',6,6'-Pentachloro-1,1'-(biphenyl)-3,4-diol 3',4'-Dihydroxy-2,4,6,2',6'-pentachlorobiphenyl 56558-19-1 PCB-155