Pollution almost as bad as smoking for unborn babies
Emissions restrict growth of infants’ heads
AIR pollution levels in Scotland are ‘almost as harmful as smoking’ to babies in the womb, warn researchers.
Higher levels of outdoor pollution are linked with reduced head growth – even within ‘safe’ air quality limits, say experts.
Their findings come after a study of almost 14,000 pregnancies in the North-East.
The results are particularly concerning because the area, which includes Aberdeen, has a ‘relatively low’ level of air pollution compared with cities such as London and Beijing.
Reduced head growth in babies, which is also caused by smoking in pregnancy, is linked to brain development problems. Last night there were calls for tougher limits on air pollution from cars and factories.
Scientists at the School of GeoSciences at Edinburgh University and the department of child health at Aberdeen University examined ultrasound scans of women attending Aberdeen Maternity Hospital and linked them with air pollution levels in the women’s postcode areas.
Dr Tom Clemens, of Edinburgh University, said: ‘Our results suggest the highest concentrations of air pollu- tion may reduce babies’ head growth. This effect appears to be comparable to the effect of maternal smoking.
‘On average, foetuses with nonsmoking mothers exposed to high pollution were found to have only slightly larger head sizes than those with smoking mothers who were exposed to lower pollution.
‘This implies that the effect of exposure to the highest levels of pollution may be almost as harmful as smoking for foetal head growth.
‘The study adds to growing evidence suggesting a possible link between exposure to air pollution during pregnancy and reduced birth weights.’
The highest levels of air pollution recorded were around the maximum safe limits for the UK, while the average amounts where the women lived were well within safe limits.
But the researchers found the babies’ head measurements in the womb began to reduce even at relatively low levels of air pollution from the 25th week of pregnancy.
The experts checked recordings of airborne pollutants of greatest concern to public health. These include particulate matter small enough to be inhaled into the deepest parts of the lung, and nitrogen dioxide.
The study, published in the journal Environment International, included data from 13,775 pregnancies in 12,467 mothers between 2002 and 2011 and adds: ‘The study was conducted in an environment with relatively low level of air pollution. Despite these persistently low exposures, we still observe significant foetal growth restriction which should be of concern.’
Dr Patrick O’Brien, of the Royal College of Obstetricians and Gynaecolo-
‘Possible link with birth weights’ ‘We recommend lifestyle changes’
gists, said: ‘The research should place renewed pressure on Governments to take further action on reducing air pollution levels.
‘Exposure to some level of air pollution is unavoidable in day-to-day life. We would recommend that women reduce their exposure to air pollution and make lifestyle changes, such as quitting smoking.’
A Scottish Government spokesman said: ‘Scotland is the first country in Europe to pass legislation based on World Health Organisation guidelines on the most dangerous pollutants, and our Cleaner Air for Scotland strategy sets out to promote air quality.’