February 6, 2013

expert reaction to air pollution and birth weight

A large study, using data from UK, Europe, North America, South America, Asia and Australia, found that pregnant mothers exposed to air pollution are more likely to have smaller babies. The research was published in Environmental Health Perspectives.

Prof Kevin McConway, Professor of Applied Statistics, The Open University, said:

“The study provides evidence that the higher the level of a certain kind of air pollution, the greater the rate of low birth weight. But we mustn’t read too much into it. Though the rate of low birth weight does appear to change as air pollution changes, it doesn’t change very much. Suppose we could halve the amount of particulate air pollution in Newcastle from its current level. According to figures from this study, that would lead to around two or three fewer low birth weight births in a year, out of the 3500 or so births to Newcastle mothers. That sort of reduction might well be worth having, but it’s not something that pregnant mothers should lose sleep over, I’d say.“

Dr Tony Fletcher, Senior Lecturer in Environmental Epidemiology, London School of Hygiene and Tropical Medicine, said:

“This new study is very helpful in establishing another health impact of air pollution. Because the average effect is quite small, it needs enormous multi-country studies such as these to quantify the effect.  The study is of excellent quality and the conclusions are clear: while the average effect on each baby is small and so should not alarm individual prospective parents, for the whole population these small risks add up across millions of people. Another reason for London and other large cities to force traffic-related pollution down to lower levels.”

‘Maternal Exposure to Particulate Air Pollution and Term Birth Weight: A Multi-Country Evaluation of Effect and Heterogeneity’ by Dadvand et al.  published in Environmental Health Perspectives on Wednesday 6th February.