Pollution in towns and cities pushes the risk of premature birth up by 30 per cent, scientists have claimed.

The researchers, from the University of California, looked at 100,000 births within a five-mile radius of air quality testing stations in the state. They found that expectant mothers who were exposed to traffic fumes - and in particular a by-product of petrol called polycyclic aromatic hydrocarbons (PAH) were three times more likely to have a premature baby than those that weren't.

Other chemicals were also found to increase the risks of premature birth, including ammonium nitrate (21 per cent) benzene (10 per cent) and diesel (10 per cent).

The findings were published in the journal Environmental Health. Lead researcher Dr Beate Ritz said: "Air pollution is known to be associated with low birth weight and premature birth.

"Our results show traffic-related PAH are of special concern as pollutants and that PAH sources besides traffic contributed to premature birth.

"The increase in risk due to ammonium nitrate particles suggests secondary pollutants are also negatively impacting the health of unborn babies."

Posted by Robert Mair