In 2019, research published in the scientific journal Nature Communications showed that black carbon particles (the popular soot) can cross the placenta. Now researchers at Queen Mary University in London have found that other particles resulting from pollution (including metals) can also contaminate the life-supporting structure of the fetus.
Placentas donated by 15 healthy parturients admitted to the Royal Hospital in London were examined. In 13 women, the researchers found evidence of exposure to pollution above the average annual limit determined by the World Health Organization (WHO).
They appeared in 1% of the cells analyzed, in all placentas. What has been discovered is that particles suspended in highly polluted environments, when inhaled, travel from the lungs to distant organs, being agglutinated by certain cells of the human placenta and, potentially, that of the fetus.
“We always thought that the mother’s inhalation could result in pollution particles traveling to the maternal placenta, even though we know that there are defense mechanisms in the lung that prevent foreign particles from migrating to another place. So it was surprising to identify them in the placenta cells of all 15 participants, ”said molecular biologist Lisa Miyashita.
In addition to the expected carbon-based particles, the researchers found traces of metals in the placenta, such as silica, phosphorus, calcium, iron, chromium and, more rarely, titanium, cobalt, zinc and cerium.
The study, published in the journal Science of The Total Environment, points to the heavy traffic in the English capital as the source of the elements – they are residues from the combustion of fossil fuel, in addition to the use of additives added to gasoline and oil, as well as the wear and tear of the fuel. asphalt, due to vehicle brakes.
For the Queen Mary University study group, further research is still needed to determine what effects these pollution particles can have directly on the fetus’s development. According to pediatrician and researcher Norrice Liu, “we know that there is a link between maternal exposure to high levels of pollution and problems with the fetus, including risk of low birth weight, but, until now, we had a limited view of how this can to occur”.