“…Since Merz [1961] first reported breakage of chromosomes by mitomycin C (MMC), the induction of chromosome aberrations and sister chromatid exchanges by this bifunctional alkylating agent has been documented in a wide variety of cells [eg, Nowell, 1964;Morad et al, 1973;Au et al, 1980;Gupta and Sharma, 1982;Kocan et al, 1982;Sandberg, 1982;Wolff, 1982;Cervenka and Hirsch, 1983;De Marco and Polani, 1983;Dulout and Olivero, 19841. As a consequence, MMC is now generally viewed as a good positive control chemical in tests with chromosome change as the mutagenic endpoint.…”