Responses of the l5178y tk+/tk− mouse lymphoma cell forward mutation assay: III. 72 Coded chemicals

Abstract

Seventy‐two chemicals were tested for their mutagenic potential in the L5178Y tk+/− mouse lymphoma cell forward mutation assay, using 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 allyl isothiocyanate, p‐benzoquinone dioxime, benzyl acetate, 2‐biphenylamine HCl, bis(2‐chloro‐1‐methylethyl)ether, cadmium chloride, chlordane, chlorobenzene, chlorobenzilate, 2‐chloroethanol, chlorothalonil, cytarabine‐HCl, p,p′‐DDE, diazinon, 2,6‐dichloro‐p‐phenylenediamine, N,N‐diethylthiourea, diglycidylresorcinol ether, 2,4‐dimethoxy aniline‐HCl, disperse yellow 3, endosulfan, 1,2‐epoxyhexa‐decane, ethyl acrylate, ethyl benzene, ethylene thiourea, F D and C yellow Number 6, furan, heptachlor, isophorone, mercuric chloride, 4,4′‐methylenedianiline 2 HCl, methyl viologen, nickel sulfate‐6H 2 O, 4,4′‐oxydianiline, pentachloroethane, piperonyl butoxide, propyl gallate, quinoline, rotenone, 2,4,5,6‐tetrachloro‐4‐nitro‐anisole, 1,1,1,2‐tetrachloroethane, trichlorfon, 2,4,6‐trichlorophenol, 2,4,5‐trimetho‐xybenzaldehyde, 1,1,3‐trimethyl‐2‐thiourea, 1‐vinyl‐3‐cyclopetene dioxide, vinyl toluene, and ziram. Apart from 2‐biphenylamine‐HCl, 2‐chloroethanol, disperse yellow 3, ethylene thiourea, FD and C yellow number 6, phenol, and 1,1,2‐tetrachloroethane, rat liver S9 mix was not a requirement for these compounds. Chemicals not identified as mutagens were acid red, 11‐aminoundecanoic acid, boric acid, 5‐chloro‐o‐toluidine, coumaphos, cyclohexanone, decabromodiphenyl oxide, di(2‐ethylhexyl)adipate, ferric chloride, fluometuron, melamine, monuron, phenesterin, phthalimide, reserpine, sodium dodecyl sulfate, 4,4‐sulfonyldianiline, tetrachloroethylene, and zearalenone. The assay was incapable of providing a clear indication of whether some chemicals were mutagens; these were benzyl alcohol, 1,4‐dichlorobenzene, phenol, succinic acid‐2,2‐dimethyl hydrazide, and toluene.