Study of the Carcinogenic Effect of Benzo[a]pyrene Compound in the Mammary Glands of Female Balb/c Mice: A Histopathological Study

Benzo[a]pyrene represents a global health threat. it spreads everywhere in the ecosystem in water, air and soil and is widely included in the daily food chain for humans. It is a major risk factor for many human cancers such as breast cancer. The previous studies that proved the carcinogenic effect of benzo[a]pyrene on the breast were very few, in addition to lacking microscopic examinations. Therefore, our current study aimed to prove the carcinogenic effect of benzo[a]pyrene in breast tissue based on histopathology. The focus was on breast cancer due to its high prevalence rate in war countries such as Syria. The experiment was carried out on 30 female Balb/c mice distributed equally into two groups. The control group was given water and food only throughout the experiment period, the experimental group was injected with benzo[a]pyrene 30 mg/kg into the abdominal peritoneum three times a week 10 months. At the end of the experiment, we conducted autopsies on mice that developed tumor masses where samples were taken from them for histological study and stained with Hematoxylin-Eosin to determine the distinctive features of the tumor tissue. A histological study was also conducted on the kidneys and livers of dead mice during the course of the experiment. The results of this study showed that benzo[a]pyrene is able to develop malignant breast tumors in experimental animals (P=0.000). This effect was clear grossly and histologically as malignant tumors of the ductal type developed in these mice.