Until a few decades ago, the popular but falsely reassuring belief was that babies in the womb were perfectly protected by the placenta and that children were just “little adults,” requiring no special protections from environmental threats. We now know that a host of chemicals, pollutants and viruses readily travel across the placenta from mother to fetus, pre-polluting or pre-infecting a baby even before birth.
Toxic chemicals like lead, certain air pollutants, pesticides, synthetic chemicals and infectious agents like Zika can derail the intricate molecular processes involved in a fetus’s healthy brain development. So can physical and social stress experienced by the mother.
