Iversen O H
Virchows Arch B Cell Pathol Incl Mol Pathol. 1979 Jun 29;30(3):363-5. doi: 10.1007/BF02889114.
Nitrosomethylurea (MNU) was tested with the tetrazolium test for skin carcinogens with positive results. 39 hairless mice were painted once a week with a 1% solution of MNU in acetone. After 18 weeks all the animals bore tumours and 90% had skin carcinomas. Hence, the strong carcinogenic potency of MNU was confirmed, and the validity of the tetrazolium test was given further support.