Studies of factors influencing the mutagenicity of EMS in mice.

Three different routes of administration of ethyl methanesulphonate (EMS) (i.p., oral, i.t.) were compared for their relative efficiencies in the induction of dominant lethal effects. Included in the comparisons between oral and i.p. injections, was a preliminary study into the existence of strain differences in sensitivity to EMS between C3D2 F1 hybrid mice and strain DBA/2J mice. No route of administration dependent effects were found between oral and i.p. injections regardless of the test animal used. I.t. injections of EMS did not induce dominant lethal effects. One treatment related strain difference was observed.