Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Ozone levels may raise risk of underweight births


USC study finds common pollutants linked to fetal growth retardation

Babies born to women exposed to high ozone levels during pregnancy are at heightened risk for being significantly underweight, according to researchers at the Keck School of Medicine of the University of Southern California.

Women who breathe air heavily polluted with ozone are at particular risk for having babies afflicted with intra uterine growth retardation-which means babies only fall within the 15th percentile of their expected size. The findings were published early online on the Web site of Environmental Health Perspectives, the journal of the National Institute for Environmental Health Sciences (NIEHS).

"These findings add further evidence that our ozone standards are not protecting the most vulnerable members of the population," says Frank D. Gilliland, M.D., Ph.D., professor of preventive medicine at the Keck School and the study’s senior author.

Gilliland and his colleagues examined birth records from 3,901 children who were born in California between 1975 and 1987 and participated in the Children’s Health Study. Researchers with the USC-led Children’s Health Study have monitored levels of major pollutants in a dozen Southern California communities since 1993, while following the respiratory health of more than 6,000 students in those communities.

The researchers gathered data such as the children’s gestational age and birth weight, as well as their mothers’ zip code of residence at birth. Then they determined levels of ozone, carbon monoxide and other pollutants in the air in each zip code of residence during each mother’s pregnancy. Researchers only considered full-term births for the study and controlled for factors such as mothers’ smoking habits.

They found that each increase of 12 parts per billion (ppb) of average daily ozone levels over a mother’s entire pregnancy was associated with a drop of 47.2 grams (g)-about a tenth of a pound-in a baby’s birth weight. And the association was even stronger for ozone exposure over the second and third trimesters, Gilliland says.

In addition, for each 17 ppb increase in average daily ozone levels during a mother’s third trimester of pregnancy, the risk of intra uterine growth retardation increased by 20 percent, the scientists report.

The effects were strongest when total average daily ozone exposure rose above 30 ppb. Ozone levels varied from less than 20 ppb in cleaner areas to above 40 ppb in more polluted areas of Southern California.

Carbon monoxide levels affected birth weight as well. They found that each increase of 1.4 parts per million of carbon monoxide concentration during the first trimester was associated with 21.7 g (about .05 pound) decrease in birth weight and a 20 percent increase in risk of intra uterine growth retardation.

Ozone, or O3, is a gas made up of three oxygen atoms. Although a natural layer of ozone in the stratosphere helps protect life on Earth from the sun’s rays, ozone at ground level is harmful to health. It is created through interactions among tailpipe exhaust, gasoline vapors, industrial emissions, chemical solvents and natural sources and is worsened by sunlight and heat.

The study findings echo results from the few, smaller studies examining the relationship between ozone and birth weight. Animal studies support the role of O3 in reduced birth weight: in these models, pregnant rats were particularly vulnerable to lung inflammation from O3. Researchers suspect that inflammation from O3 may prompt the release of certain chemicals into the bloodstream, which may harm the placenta.

Carbon monoxide, meanwhile, is an odorless gas that primarily comes from vehicle exhaust. In high concentrations, the gas can harm healthy people; and in lower concentrations, it can hurt those with heart disease and can affect the nervous system.

The gas reduces hemoglobin’s ability to carry oxygen where it is needed in the body; that may hurt the delivery of oxygen to a fetus. However, more research is needed to understand the roles of ozone and carbon monoxide in fetal development.

"Fetal growth and birth weight are strongly linked to morbidity and mortality during childhood and adulthood," Gilliland says, "so it’s clear that air quality is important to everyone’s healthy development."

Kathleen O’Neil | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>