New study reveals air pollution particles found in mothers' placentas

Scientists believe that they have discovered the first examples of air pollution passing through the lungs of pregnant women and entering their placentas, potentially reaching their fetuses.

The study, presented at the International Congress of the European Respiratory Society in Paris, examined the placentas of five pregnant women in the UK and found that soot particles had penetrated their placentas.

"We do not know if the particles we found could also move into the fetus, but our evidence suggests that this is indeed possible," Dr. Norrice Liu, pediatrician and academic researcher at Queen Mary University in London, who led the research, said in a statement.

"We also know that particles do not need to enter the baby's body to have an adverse effect, because if they have an effect on the placenta, this will have a direct impact on the fetus."

The five pregnant women who participated in the study all lived in London and had to plan deliveries by caesarean section. All five were non-smokers and gave birth to a healthy baby after an uncomplicated pregnancy.

Each of the women consented to have her placenta, an organ that attaches to the uterus during pregnancy and connects the mother to the fetus, examined by the research team.

The placenta allows oxygen and nutrients to cross the blood supply from the mother to the fetus through the umbilical cord and also ensures the elimination of any waste.

This particular study focused on placental macrophages. These cells are part of the body's immune system and attack harmful particles such as bacteria and pollution particles, and play a key role in protecting the placenta.

According to the report, the team examined 3,500 macrophage cells from the five placentas, finding that 60 cells contained 72 dark areas between them, which researchers believe to be carbon particles.

"We have known for some time that air pollution affects the development of the fetus and can continue to affect babies after birth and throughout their lives," said Dr. Lisa Miyashita of Queen Mary University.

"We were interested to see if these effects could be due to pollution particles moving from the mother's lungs to the placenta. Until now, there was very little evidence that inhaled particles enter the blood through the lungs.

Dr. Mina Gaga, president of the European Respiratory Society, added that "this new research suggests a possible mechanism of how babies are affected by pollution while theoretically protected in the womb."

"We need stricter policies for cleaner air to reduce the impact of pollution on health worldwide, as we are already seeing a new population of young adults with health problems," he said. she said.

The research is in its infancy, but results are based on previous research highlighting the links between exposure of pregnant women to air pollution and infant mortality, premature births and underweight at birth.

"We have strong evidence that higher levels of air pollution by traffic in London are associated with a higher risk of adverse consequences for pregnancy, such as babies born with low weight at birth. birth. This groundbreaking research provides a new insight into the potential mechanisms to explain this association and deepens our understanding of the causal pathways to the disease, "said Dr. Mireille Toledano, Director of Perinatal and Pediatric Environmental Epidemiology at Imperial College London. research.

"It is clear that current levels of air pollution do not provide sufficient protection for pregnant women and their unborn children, and policy-makers need to address these urgently to improve public health."

A report released by UNICEF in December 2017 indicates that nearly 17 million babies under one year old live in areas where pollution is at least six times greater than international limits.