Positive effect of caprolactam in the mammalian spot test - an overview.

Caprolactam, a compound which has been classified as a noncarcinogen was positive in Drosophila utilizing mitotic recombination and mutation assays. Due to this unexpected finding it has been suggested for in vivo investigation by the International Programme on Chemical Safety. For this reason, the mammalian spot test with mice was performed in two independent laboratories. Although different mouse strains were used, the results obtained were nearly identical. In both laboratories the mutagenic/recombinogenic potency of caprolactam at the doses studied approximates a doubling of the spontaneous frequency.