4-tert-Octylphenol, an endocrine-disrupting chemical with estrogenic properties, notably induces apoptosis in offspring mouse brain neuronal progenitor cells. This compound decreases levels of bromodeoxyuridine (BrdU), mitotic marker Ki67, and phospho-histone H3 (p-Histone-H3), thereby diminishing the proliferation of neuronal progenitors. Consequently, 4-tert-Octylphenol adversely affects brain development and behavior in mice.