weekly topical application of equitoxic doses of n-nitrosobis ( 2-oxopropyl ) amine ( bop ) or n-nitroso ( 2-hydroxypropyl ) ( 2-oxopropyl ) amine ( hpop ) to lip and/or vagina of female syrian hamsters led to the development of papillomas and carcinomas of the lip , papillomas of the vagina , and tumors of internal organs .
C0023759
lip
C0149637
carcinomas of the lip