A new study published in the British Medical Journal (BMJ) found that exposure to air pollution from road traffic has a negative effect on fetal growth, increasing the chance for low term birth weight.
The study was the largest U.K. study on air pollution and birth weight. It took place from 2006 to 2010 in Greater London and surrounding counties and measured the weight of 540,365 babies born at term to women living in those areas.
It found that for every 5 microgram per cubic meter increase in PM 2.5 (fine particulate matter) from traffic pollution, the risk of low birth weight increased by 15 percent.
Term low birth weight, defined in the study as a weight less than 5 pounds 8 ounces, can have lifelong implications for health, with increased risk for diabetes, heart disease and hypertension in later life.
“The results from this large study add to a growing body of evidence on the association between air pollution from road traffic and its adverse impact on babies’ health, even before they are born,” Dr Patrick O’Brien, spokesperson for the Royal College of Obstetricians and Gynaecologists (RCOG) said in an email statement to WebMD. “It should place renewed pressure on Governments to adopt meaningful environmental health policies to reduce air pollution and give babies a healthier start in life.”
Currently, the Environmental Protection Agency standard for fine particulate matter is 12 micrograms per cubic meter, averaged over three years. But Mireille B. Toledano, lead author of the BMJ study, says there is really no safe level of air pollution.
“For every 10 percent reduction in PM 2.5,” she said, “we can prevent 90 babies being born with low birth weight in London. The current limits are not protecting pregnant women, and they’re not protecting unborn babies.”