Benzo[a]pyrene (3,4-Benzopyrene) shows lung carcinogenicity in mice in a dose-dependent manner.

lung tumorigenesis induced by Benzo[a]pyrene(B[a]P) was dose dependent in female A/J mice.?The incidence of hyperplasia values in females treated with 0.25, 0.50, and 1.0 mg B[a]P were significantly higher than in the vehicle-treated group.?The incidence of adenoma in females receiving 1.0 mg B[a]P was significantly higher than in the vehicle group.?The multiplicity of hyperplasia in females receiving 0.50 or 1.0 mg B[a]P was significantly higher than in the vehicle group.?The multiplicity of adenoma in the group treated with 1.0 mg was also significantly higher than in the vehicle group.?The incidences of hyperplasia and adenoma in female A/J mice were significantly increased by B[a]P in a dose-dependent manner.?Proliferative lesions in the lungs were classified as bronchiolar-alveolar hyperplasia or adenoma, and no malignant neoplasms (adenocarcinoma) were observed[1].

After a 1- or 2-week acclimatization period, 360 adult male A/J mice and 520 adult female A/J mice were used for the experiment.?Mice were allocated, using a body weight-based randomization process, to a total of 22 groups.?Briefly, each animal received a single intraperitoneal administration of one of the initiators, at one of the indicated doses, on day 1.?The animals were observed daily for clinical signs and mortality, and body weights were measured weekly.?Following an overnight fast at 26 weeks after dosing, all mice were anesthetized with sevoflurane and weighed.?They were then sacrificed by exsanguination from the abdominal aorta and caudal vena cava and subjected to necropsy[1].