Here’s how pollution gets to your baby inside the womb

Yes, air pollution is bad for you. But when you are pregnant and wallowing in it, you just might be endangering the future of your unborn child. Scientists have found evidence that particles of air pollution travel through pregnant women’s lungs and lodge in their placentas. There already is a strong link between polluted air […]

Yes, air pollution is bad for you. But when you are pregnant and wallowing in it, you just might be endangering the future of your unborn child.

Scientists have found evidence that particles of air pollution travel through pregnant women’s lungs and lodge in their placentas.

There already is a strong link between polluted air and harm in foetuses but exactly how that happens is unknown. Until now.

The new study involving mothers living in London reveal sooty particles in the placenta of each of their babies. It is believed the particles possibly entered the foetuses too.

“It is a worrying problem – there is a massive association between air pollution a mother breathes in and the effect it has on the foetus,” said Dr Lisa Miyashita, at Queen Mary University of London, one of the research team.

“It is always good if possible to take less polluted routes if you are pregnant – or indeed if you are not pregnant.”

The new research examined the placentas of five non-smoking women who all delivered healthy babies. The researchers isolated macrophage cells, which are part of the body’s immune system and engulf harmful particles such as bacteria and air pollution.

Using an optical microscope, they found 72 dark particles among 3,500 cells and then used a powerful electron microscope to examine the shape of some of the particles. They looked very like the sooty particles found in macrophages in the lung, which catch many – but not all – of the particles.

While further analysis is needed for final confirmation, Dr Miyashita said: “We can’t think of anything else they could be. It is very evident to us they are black sooty particles.” Earlier experiments have shown that particles breathed in by pregnant animals go through the bloodstream into placentas.

“We do not know whether the particles we found could also move across into the foetus, but our evidence suggests this is indeed possible,” said Dr Norrice Liu, also at Queen Mary University of London and part of the team. “We also know that the particles do not need to get into 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 foetus.”

Previous studies show air pollution significantly increases the risk of premature birth and of low birth weight, leading to lifelong damage to health.

A large study of more than 500,000 births in London, published in December, confirmed the link and led doctors to say that the implications for many millions of women in polluted cities around the world are “something approaching a public health catastrophe”.

Scientists are increasingly finding that air pollution results in health problems far beyond the lungs. In August, research revealed that air pollution causes a “huge” reduction in intelligence, while in 2016 toxic nanoparticles from air pollution were discovered in human brains.

Mina Gaga, president of the European Respiratory Society and at the Athens Chest Hospital in Greece.

“This should raise awareness amongst doctors and the public regarding the harmful effects of air pollution in pregnant women,” she said, noting that harm to foetuses can occur even below current European Union pollution limits.

“We need stricter policies for cleaner air to reduce the impact of pollution on health worldwide because we are already seeing a new population of young adults with health issues.”

Unicef executive director Anthony Lake recently warned of the danger of air pollution to babies: “Not only do pollutants harm babies’ developing lungs, they can permanently damage their developing brains – and, thus, their futures.”