It is commonly known that smoking while pregnant increases the risk of health problems for unborn infants. Smoking can induce preterm birth, and cause birth defects of the mouth and lips. Scientists have now made the startling discovery that simply living in an area with high air pollution could have similar implications.
A recent 2019 study into the effects of air pollution on foetal development has discovered black carbon particles inside the placentas of multiple woman in Belgium. Researchers who conducted the study said that this was the first evidence of harmful particles penetrating the placental barrier.
Black carbon particles are released into the air via the burning of fossil fuels or wood. Therefore, everyone is exposed to it via their cars, wood-burning stoves and forest fires. Black carbon can have serious health effects, and is one of the most common climate pollutants we encounter on a daily basis.
Researchers examined placenta samples from 28 women living in Belgium: 10 living in high-level pollution areas, 10 from low-level pollution areas, five women that had preterm births, and three randomly selected women from average-level pollution areas.
By using high-resolution imaging to detect the black carbon particles, scientists discovered that trace amounts of black carbon particles were beginning to form on the inside walls of the pregnant women’s placenta. However, scientists note that there is no evidence of the harmful particle reaching the foetus itself.
While all women studied presented with black carbon in their placentas, women in high-level pollution areas presented with much more. Mothers residing in high levels of air pollution were subject to about 2,42 micrograms per cubic meter of black carbon particles compared to mothers who lived in areas with low levels of air pollution, who only came into contact with 0.63 micrograms per cubic meter. This indicates that woman who live in areas with high residential pollution could have more than double the amount of black carbon particles reach their placentas than woman who lived in areas with low residential pollution.
Jenifer Salmond, Associate Professor at the University of Aukland’s School of Environment, argues that the harmful toxin could still effect the placenta despite no evidence of it interacting with the foetus. This in turn could lead to complications during the pregnancy or during birth. She argues that poor air quality could explain the reason for low birth weights in infants, and this newly found information backs up her theory. Other studies have shown that foetuses with exposure to higher levels of particulate matter are more likely to have high blood pressure.