London (CNN) Scientists believe they have discovered the first examples of air pollution traveling through the lungs of pregnant women and into their placentas, potentially reaching their fetuses. 
 
 The study, presented at the European Respiratory Society International Congress in Paris, examined the placentas of five pregnant women in the United Kingdom and found that sooty particles had made their way into their placentas. 
 
 "We do not know whether the particles we found could also move across into the fetus, but our evidence suggests that this is indeed possible," Dr. Norrice Liu, a pediatrician and clinical research fellow at Queen Mary University in London who led the research, said in a statement. 
 
 "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 fetus." 
 
 The five pregnant women who took part in the study all lived in London and were scheduled to have planned cesarean section deliveries. All five were non-smokers and gave birth to a healthy baby after uncomplicated pregnancies. 
 
 Each of the women consented to having their placenta, an organ that attaches itself to the womb during pregnancy and links the mother to the fetus, examined by the research team. 
 
 The placenta allows oxygen and nutrients to pass through the mother's blood supply to the fetus through the umbilical cord and also ensures the disposal of any waste.. 
 
 This particular study looked at placental macrophages. These cells are part of the body's immune system and tackle harmful particles such as bacteria and pollution particles, and are key in helping to protect the placenta. 
 
 According to the report, the team examined 3,500 macrophage cells from the five placentas, finding that 60 of the cells contained 72 dark areas between them, which the researchers believe were carbon particles. 
 
 "We've known for a while that air pollution affects fetal development and can continue to affect babies after birth and throughout their lives," said Dr. Lisa Miyashita, at Queen Mary University of London, who also presented the research. 
 
 "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 has been very little evidence that inhaled particles get into the blood from the lung." 
 
 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 being theoretically protected in the womb." 
 
 "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," she said in a statement. 
 
 The research is at an early stage, but the findings build on previous research highlighting links between the exposure of pregnant mothers to air pollution and infant mortality, premature birth and low birth weight. 
 
 "We have strong evidence that higher levels of road traffic air pollution in London are associated with higher risk of adverse pregnancy outcomes, such as babies born of low birthweight. This innovative research provides new insight into potential mechanisms to explain this association and further our understanding of causal pathways to disease," said Dr. Mireille Toledano, chair in Perinatal and Paediatric Environmental Epidemiology, at Imperial College London, who was not involved in the new research. 
 
 "It is clear that current regulatory air pollution levels are not sufficiently protecting pregnant women and their unborn babies and this needs to be urgently addressed by policy makers to improve public health." ||||| Scientists have found the first evidence that particles of air pollution travel through pregnant women’s lungs and lodge in their placentas. 
 
 Toxic air is already strongly linked to harm in foetuses but how the damage is done is unknown. The new study, involving mothers living in London, UK, revealed sooty particles in the placentas of each of their babies and researchers say it is quite possible the particles 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. I avoid busy roads when I walk to the station.” 
 
 A series of previous studies have shown that 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”. 
 
 Air pollution harm to unborn babies may be global health catastrophe, warn doctors Read more 
 
 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. 
 
 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.” 
 
 The research is being presented Sunday at the European Respiratory Society’s (ERS) international congress in Paris. “This research suggests a possible mechanism of how babies are affected by pollution while being theoretically protected in the womb,” said Prof Mina Gaga, who is ERS president 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.” 
 
 Separate research, also presented at the ERS congress, found that children with early onset and persistent asthma fared far less well in education than those without the condition. Asthma in children has long been linked to air pollution. 
 
 The study, conducted over 20 years in Sweden, showed that children with asthma were three and half times more likely to leave school at the age of 16 with only basic education and were also twice as likely to drop out of university courses. 
 
 Dr Christian Schyllert, at the Karolinska University Hospital in Stockholm, said: “This study suggests [these] children have worse life chances when it comes to their education and their future jobs.” He said one possible reason could be that children with asthma are known to have lower school attendance.
– The womb protects a developing fetus, but it might not be able to fend off air pollution. Researchers have presented a small study suggesting for the first time that air pollutants can make their way from a pregnant woman's lungs to her placenta, reports the Guardian. Because the placenta allows nutrients and oxygen to flow from the woman's blood stream to her fetus, that means it could similarly allow pollutants into the womb as well, per CNN. "Our evidence suggests that this is indeed possible," says Norrice Liu, a pediatrician who led the research at Queen Mary University in London. "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 fetus." The study, presented at the European Respiratory Society International Congress in Paris, was indeed small, involving just five women. But researchers found "black sooty" particles, believed to be carbon, in the placentas of each one, says another of the researchers, Lisa Miyashita. Further analysis is in the works to confirm, but the results mirror similar ones in animals. Given previous research laying out the potential dangers that air pollution can cause to babies, the scientists say the study should factor into the advice given to pregnant women, even if it's as simple as wearing a mask or avoiding especially busy roads when out and about. The good news: All five of the women gave birth to healthy babies. (Air pollution might be the world's greatest killer.)