Genotoxicity of epoxy resin hardeners in the hepatocyte primary culture/DNA repair test.

The genotoxicity of 9 chemicals used as epoxy resin hardeners was examined in the DNA repair test with rat hepatocytes. DNA repair synthesis was elicited by 7 chemicals, i.e., 4-aminodiphenyl ether, 4,4-diaminodiphenyl ether, 3,4,4'-triaminodiphenyl ether, 3,3'-dichloro-4,4'-diaminodiphenyl ether, 1,3-phenylenedi-4-aminophenyl ether, 4,4'-diaminodiphenyl methane and 4,4'-methylene-bis(2-chloroaniline). The positive results obtained with 4 epoxy resin hardeners of unknown carcinogenicity, i.e., 4-amino-diphenyl ether, 3,4,4'-triaminodiphenyl ether, 3,3'-dichloro-4,4'-diaminodiphenyl ether and 1,3-phenylene-di-4-aminophenyl ether suggest that they may be carcinogens. The genotoxicity of 1,4-phenylene-di-4-aminophenyl ether, of unknown carcinogenicity, and 4,4'-diaminodiphenyl sulfone, for which there is no sound proof of carcinogenicity, was not confirmed in the DNA repair test. The result with 4,4'-diaminodiphenyl sulfone was in agreement with its lack of mutagenicity in Salmonella typhimurium.