64,000 die in womb a year due to air pollution

Actual toll would have been higher without steps taken by Beijing, university study finds

Fine particles in the country’s polluted air kill up to 64,000 babies in the womb every year, a new study has found.

The shocking figure comes despite efforts by Beijing to tackle the problem over the past 10 or more years.

An analysis of 137 countries revealed that 40 per cent of stillbirths in Asia, Africa and Latin America in 2015 were caused by exposure to particles smaller than 2.5 microns (PM2.5), which are mostly produced by the burning of fossil fuels.

Of all the countries studied – where 98 per cent of the world’s stillbirths occur – China ranked fourth in terms of the number of PM2.5-related fetal deaths, according to the study published in the peer-reviewed scientific journal Nature Communications.

The researchers from Peking University – led by Xue Tao – were keen to point out that measures taken by the authorities in Beijing to tackle air pollution over the past decade had prevented even more such deaths. “Improved air quality in some of the 137 countries [e.g. China] might underlie the reduction in the global burden of stillbirths. Therefore, meeting the World Health Organization air quality targets could prevent stillbirths,” they wrote.

India, with 217,000 in 2015, recorded the largest number of PM 2.5-related stillbirths, followed by Pakistan and Nigeria, the study found.

While the link between dirty air and stillbirth is widely known, the study is the first to calculate the actual number of fetal deaths. The phenomenon was described by Unicef in a 2020 report as a “neglected tragedy”.

More than 2 million stillbirths were recorded in the studied countries in 2015, of which 40 per cent were linked to PM2.5 exposure exceeding the WHO guideline level of 10 μg/m3.

Overall, the study found that a 10 μg/m3 increase in PM2.5 exposure was associated with an 11 per cent increase in the risk of stillbirth, and the older the mother is, the stronger the association.

It was still unclear how PM2.5 causes fetal deaths, but the researchers said pollution particles passing through the placenta may lead to “irreversible embryonic damage”. It could also hinder oxygen transmission to the fetus.

PM2.5 pollution became a public concern in China a decade ago when major cities were frequently shrouded in heavy smog, triggering a series of government actions.