[Mutagenic activity of benzonal]

Benzonalum mutagenic activity was demonstrated in a dominant lethal test on mice. The late spermatids stage proved to be the most sensitive in this respect. The benzonalum did not evoke any cytogenetic activity, that was shown by counting chromosome aberrations in metaphases of the bone marrow cells in vivo and did not induce gene mutations in tester trains of Salmonella typhimurium in vitro and in vivo (a host-mediated assay).