*2.7. Sampling*

#### 2.7.1. Breast Tissue Samples

Samples were obtained via surgical cuts of the mammary gland of rats anesthetized in a halothane chamber and then euthanized by cervical dislocation to avoid animal suffering, as per the NOM-033-ZOO-1995 and NOM-062-ZOO-1999 Official Mexican Standards, European Medicines Agency (EMEA, Amsterdam, The Netherlands, 2009), and Food and Drug Administration (FDA, Silver Spring, MD, USA, 2014) [34–37]. After quantifying the aluminum concentration, the samples were used for histopathological evaluation and total RNA extraction to evaluate the genetic expression of *BRCA1* and *SCL11a2*.
