News / Health

Air Pollution Raises Risk of Low Birth Weight Babies

Smog from smokestacks, automobiles, and other sources of pollution, Los Angeles, April 2009 (file photo).
Smog from smokestacks, automobiles, and other sources of pollution, Los Angeles, April 2009 (file photo).
Jessica Berman
The largest study ever conducted on air pollution's impact on newborn health has found that pregnant women exposed to black soot from urban vehicles and coal-fired power plants are more likely to have low birth-weight babies.  

The study by an international group of researchers analyzed data on three million births collected at 14 sites in nine countries in North America, South America, Asia and Australia.  It covered about 15 years beginning in the mid-1990s.

The massive survey found that at all these sites, pregnant women who breathed the most polluted air - as measured by carbon soot concentrations - were significantly more likely to have babies with low birth weights - below 2,500 grams or 5.5 pounds.  At that size, a baby - if he or she survives infancy - is at risk of chronic health problems and learning disabilities later in life.

Particulate air pollution is determined by a combination of soot particles' concentration in a cubic meter of air, and their size, measured in microns.  Tracey Woodruff, a professor of obstetrics and gynecology at the University of California San Francisco, and a co-principal investigator on the study, says this microscopic dust - smaller than the width of human hair - is in the air we all breathe.  Its impact on our health varies with the concentration and size of the particulate matter.  Woodruff says a relatively low concentration of 10-micron soot particles. . .

“...was associated with a 3 percent increase in the risk of having a low birth-weight baby," said Woodruff. "So the risk at the individual level is modest, but we’re talking about many, many, many women around the world (being) exposed.”

In the United States, Clean Air laws require that soot particles measure less than 2.5 microns in size, at concentrations of no more than 12 micrograms per cubic meter.  In Europe, the limit is 25 micrograms.  In Beijing, China, soot concentrations were measured recently at more than 700 micrograms per cubic meter.  Urban areas in South Asia are also reporting dangerously high soot concentrations.

Woodruff says there are several possible reasons why this kind of air pollution causes low birth-weight in infants.

“It could be that because particulate air pollution is affecting the health of the mother, that that in turn affects the health of the developing fetus," she said. "Or it could be that some of these particles actually have the ability to go into your lungs and then some of the toxic materials on the particle can get into your blood stream, and maybe that can go down to the fetus and affect development in that way.”

The scientists got their data from centers participating in the International Collaboration on Air Pollution and Pregnancy Outcomes, a global research initiative launched in 2007 to assess the impact of urban air pollution on pregnancy and newborn health.
 
An article on air pollution and low birth weight is published in the journal Environmental Health Perspectives.  

You May Like

Video One Year After Thai Coup, No End in Sight for Military Rule

Since carrying out the May 22, 2014 coup, the general has retired from the military but is still firmly in charge More

Video Afghan Economy Sinks As Troops Depart

Afghans are grappling with how exodus will affect country's fragile economy More

Video Scientists Say We Need Softer Robots

Today’s robots are mostly hard, rigid machines, with sharp edges and forceful movements, but researchers at Carnegie Mellon University say they should be softer and therefore safer More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Turkey's Main Opposition Party Hopes for Election Breakthroughi
X
May 22, 2015 10:23 AM
Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Turkey's Main Opposition Party Hopes for Election Breakthrough

Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Europe Follows US Lead in Tackling ‘Conflict Minerals’

Metals mined from conflict zones in places like the Democratic Republic of Congo are often sold by warlords to buy weapons. This week European lawmakers voted to force manufacturers to prove that their supply chains are not inadvertently fueling conflicts and human rights abuses. Henry Ridgwell reports from London.
Video

Video Class Tackles Questions of Race, Discrimination

Unrest in some U.S. cities is more than just a trending news item at Ladue Middle School in St. Louis, Missouri. As VOA’s Kane Farabaugh reports, it’s a focus of a multicultural studies class engaging students in wide-ranging discussions about racial tensions and police aggression.
Video

Video Mind-Controlled Prosthetics Are Getting Closer

Scientists and engineers are making substantial advances towards the ultimate goal in prosthetics – creation of limbs that can be controlled by the wearer’s mind. Thanks to sophisticated sensors capable of picking up the brain’s signals, an amputee in Iceland is literally bringing us one step closer to that goal. VOA’s George Putic reports.
Video

Video Afghan Economy Sinks As Foreign Troops Depart

As international troops prepare to leave Afghanistan, and many foreign aid groups follow, Afghans are grappling with how the exodus will affect the country's fragile economy. Ayesha Tanzeem reports from the Afghan capital, Kabul.
Video

Video Poverty, Ignorance Force Underage Girls Into Marriage

The recent marriage of a 17-year old Chechen girl to a local police chief who was 30 years older and already had a wife caused an outcry in Russia and beyond. The bride was reportedly forced to marry and her parents were intimidated into giving their consent. The union spotlighted yet again the plight of many underage girls in developing countries. Zlatica Hoke reports poverty, ignorance and fear are behind the practice, especially in Asia and Africa.
Video

Video South Korea Marks Gwangju Uprising Anniversary

South Korea this week marked the 35th anniversary of a protest that turned deadly. The Gwangju Uprising is credited with starting the country’s democratic revolution after it was violently quelled by South Korea’s former military rulers. But as Jason Strother reports, some observers worry that democracy has recently been eroded.
Video

Video California’s Water System Not Created To Handle Current Drought

The drought in California is moving into its fourth year. While the state's governor is mandating a reduction in urban water use, most of the water used in California is for agriculture. But both city dwellers and farmers are feeling the impact of the drought. Some experts say the state’s water system was not created to handle long periods of drought. Elizabeth Lee reports from Ventura County, an agricultural region just northwest of Los Angeles.
Video

Video How to Clone a Mammoth: The Science of De-Extinction

An international team of scientists has sequenced the complete genome of the woolly mammoth. Led by the Swedish Museum of Natural History in Stockholm, the work opens the door to recreate the huge herbivore, which last roamed the Earth 4,000 years ago. VOA’s Rosanne Skirble considers the science of de-extinction and its place on the planet
Video

Video Blind Boy Defines His Life with Music

Cole Moran was born blind. He also has cognitive delays and other birth defects. He has to learn everything by ear. Nevertheless, the 12-year-old has had an insatiable love for music since he was born. VOA’s June Soh introduces us to the young phenomenal harmonica player.

VOA Blogs