The carcinogenic effect of bis-(2-oxopropyl)-nitrosamine on Sprague-Dawley rats.

Sprague-Dawley rats received subcutaneous injections of bis-2-oxopropyl)-nitrosamine (BOPN) once weekly for life. The animals developed mainly papillomas and squamous cell carcinomas of the nasal cavity, follicle cell carcinomas of the thyroid gland and papillomas and transitional cell carcinomas of renal pelvis, ureter and urinary bladder. The tumour incidence was 100% in all the 3 treated groups. Survival time, tumour latency and multiplicity showed dose dependency.