Pregnant mice breathing polluted air give birth to small, underweight pups.
Veras, MM, NR Damaceno-Rodrigues, EG Caldini, AACM Ribeiro, TM Mayhew, PHN Saldiva and M Dolhnikoff. Particulate urban air pollution affects the functional morphology of mouse placenta. Biology of Reproduction 79, 578–584.
Breathing polluted air before and during pregnancy alters mouse fetal development by affecting the size and circulation patterns of the placenta. The smaller lifeline hinders blood and nutrient transfer from mom to pup, causing the fetuses to remain small and be born underweight. The new findings from an ongoing study in Sao Paulo, Brazil may answer the mystery of why women living in this and other very polluted cities are at risk of giving birth to lower weight babies. Veras and coworkers from School of Medicine at University of Sao Paulo studied laboratory mice purposefully raised and completing pregnancies in a San Paulo downtown garden. Some of the pregnant mice were exposed to ‘clean, filtered’ air, and others to ‘polluted, unfiltered’ air. The study found that mice living in polluted air gave birth to fetuses with low birth weight – a finding consistent with human studies. The mice exposed to polluted air while pregnant also gave birth to pups with more severe abnormalities as compared to pups born to mothers exposed before getting pregnant.