Catalysis of the reaction: 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene + H+ + 2 e- = Cl- + 1-chloro-2,2-bis(4-chlorophenyl)ethene. 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene is also known as DDE; 1-chloro-2,2-bis(4-chlorophenyl)ethene is also known as DDMU.