Responses of the L5178Y tk+/tk mouse lymphoma cell forward mutation assay ii: 18 coded chemicals

Abstract
Eighteen chemicals were tested for their mutagenic potential in the L5178Y tk+/ mouse lymphoma cell forward mutation assay by the use of procedures based upon those described by Clive and Spector [Mutat Res 44:269–278, 1975] and Clive et al [Mutat Res 59:61–108, 1979]. Cultures were exposed to the chemicals for 4 hr, then cultured for 2 days before plating in soft agar with or without trifluorothymidine (TFT), 3 μg/ml. The chemicals were tested at least twice. Significant responses were obtained with benzofuran, benzyl chloride, bromodi‐chloromethane, butylated hydroxytoluene, chlorendic acid, o‐chlorobenzalmalo‐nitrile, 1,2,3,4‐diepoxybutane, dimethyl formamide, dimethyl hydrogen phosphite, furfural, glutaraldehyde, hydroquinone, 8‐hydroxyquinoline, and resorcinol. Apart from bromodichloromethane, butylated hydroxytoluene and dimethyl hydrogen phosphite, rat liver S9 mix was not a requirement for the activity of any of these compounds. Chemicals not identified as mutagens were water, tert‐butyl alcohol, pyridine, and witch hazel.