" Cadmium is receiving a lot of attention these days because of its estrogenic properties , " said rudolph rull , a research scientist at the cancer prevention institute of california in berkeley .
“因为镉的类雌激素性很受关注。”鲁道尔拉尔说,他是加州理工学院伯克利分校预防癌症协会的科学家。
Other possibilities include weak maternal bonding , assuming a single mother is working long hours , or contact with chemicals that may have estrogenic effects - perhaps hair straighteners in the case of black preteens .