Belgian scientists have found black carbon particles on the fetal side of the placenta of 28 pregnant women exposed to air pollution. The finding needs further investigation to determine if these particles are capable of reaching the fetus.
For years, numerous studies have warned about the negative effects of exposure to air pollution in pregnant women, such as having a preterm birth or low birth weight newborns.
The fine black carbon particles, which give their soot color, are released into the air daily, largely by incomplete combustion of fossil fuels, biofuels and biomass. Its presence in the atmosphere increases the risk of respiratory and cardiovascular diseases; and it is an important factor causing global warming.
Using high-resolution images, the team —led by Tim Nawrot, a researcher at Hasselt University (Belgium)— was able to detect these black carbon particles in placentas collected from five premature births and 23 full-term births.
Moreover, the scientists found that ten mothers who had been exposed to high levels of residential carbon black particles (2.42 micrograms per m3 ) during pregnancy had higher levels of placental particles than ten other mothers exposed to low levels (0.63 micrograms per m3).
According to the authors, “to improve care during pregnancy in contaminated areas it is necessary to understand how these particles affect, both directly on the fetus or indirectly through the mother.”
More studies needed
Researchers have also described an overview of the molecular changes in the placenta —including epigenetics— caused by air pollution, in a review article published in the journal Clinical Epigenetics.
However, despite these results, the authors are cautious and argue that it is essential to carry out further studies to determine if the particles are capable of reaching the fetus.
“We need to understand if the accumulation of black carbon particles in placental tissue can be responsible for the adverse effects associated with exposure to air pollution during pregnancy,” concludes Nawrot.