Skip to content

Air Pollution Has Harmful Effects During Pregnancy

Two recent studies point out the dangers of air pollution to the developing fetus. The first study found an association with high levels of air pollution during pregnancy and lower IQ years later when the children were between the ages of 4 to 6 (as compared to women exposed to less traffic-related air pollution during pregnancy).

The second study found that soot (tiny carbon particles) from air pollution  (e.g. vehicle exhaust) are breathed in by the pregnant woman, and then make it to her placenta during pregnancy and cross over to the baby's side of the placenta. (The placentas were collected and examined after delivery.) The fact that these tiny particles found in polluted air are breathed in by the pregnant woman and reach the baby's side of the placenta and accumulate, suggests to the researchers how air pollution causes harm to the fetus. They also found that the more particles the pregnant woman was exposed to throughout pregnancy, the more particles were detected on the baby's side of the placenta ("placental load").

The placenta used to be viewed as a barrier to toxins, but NOPE - it's not. (As we already know with alcohol and drugs, etc.)

But now some good news: In the first study, pregnant women who had higher levels of folate in their blood - meaning they had better nutrition and higher intake of folic acid during pregnancy, appeared to have a protective effect on the developing baby. As the researchers said: "Maternal folate levels may modify the impact of prenatal air pollution exposure on child cognition." In those with the lowest folate levels during pregnancy, the negative effects of air pollution during pregnancy on the developing fetus appeared to be the strongest (6.8 points lower IQ). Folate is naturally occurring in many fruits, vegetables, beans, peas, and nuts, and is in the form of folic acid in vitamin supplements. Best is a good diet.

From Medical Xpress: Offspring of pregnant women exposed to high level of pollutants may have lower IQs  

A new study found that pregnant women exposed to higher levels of air pollutants had children with lower IQs, compared to the children of women exposed to lower levels.

Researchers looked at 1,005 pregnant women participating in the Conditions Affecting Neurodevelopment and Learning study, set in Shelby County, Tenn., and assessed the IQs of their offspring between the ages of 4 and 6. They found that exposure to PM10—pollutant particles with a diameter of one-seventh the width of a human hair that are produced by industry, power plants, cars, air traffic and railways —was negatively associated with IQ. Children whose mothers were in the highest 10 percent of exposure had IQ scores that were 2.5 points lower than those in the lower 10 percent.

When the researchers looked at plasma levels of maternal folate, which is found naturally in leafy vegetables, beans and citrus fruit, and is recommended for all pregnant women in its synthetic form as folic acid, they found that the difference between offspring IQs in the highest and lowest PM10-exposed groups had widened to 6.8 points among those whose mothers had the lowest levels (bottom 25 percent) of folate.

PM10 exposure had no impact on IQ if maternal levels of folate were higher, the researchers found.

While the study underlines the importance of folic acid in pregnancy, there may be such a thing as too much folic acid supplementation, said first author Christine Loftus, an epidemiologist from the UW's Department of Environmental & Occupational Health Sciences. "Although supplementation has been shown to be protective against neural tube defects, which are devastating birth defects of the central nervous system, recent research suggests that too much prenatal folic acid may impair healthy fetal neurodevelopment," Loftus said. "The dose of folic acid is something that pregnant women should discuss with their doctors."

Long-term exposure to PM10 has been linked to reduced lung function and the development of cardiovascular and respiratory diseases. In this study, other pollutants, including nitrogen dioxide, which is a marker for high-concentration motor traffic, were not found to impact IQ.

The authors said that they could not explain the mechanism by which PM10 exposure contributed to lower IQ, but said that animal studies indicated that air pollution exposure increased maternal inflammation and oxidative stress. "This could result in placental inflammation and may interfere with placental or fetal epigenetic programming," said senior author Kaja LeWinn, ScD, associate professor of psychiatry at the UCSF School of Medicine.

From Medical Xpress: Study finds air pollution reaches placenta during pregnancy

A new study suggests when a pregnant woman breathes in air pollution, it can travel beyond her lungs to the placenta that guards her fetus.

Pollution composed of tiny particles from car exhaust, factory smokestacks and other sources is dangerous to everyone's health, and during pregnancy it's been linked to premature births and low birth weight. But scientists don't understand why, something that could affect care for women in highly polluted areas. One theory is that the particles lodge in mom's lungs and trigger potentially harmful inflammation.

Tuesday, Belgian researchers reported another possibility, that any risk might be more direct. A novel scanning technique spotted a type of particle pollutionsootlike black carbon—on placentas donated by 28 new mothers, they reported in Nature Communications.

The placenta nourishes a developing fetus and tries to block damaging substances in the mother's bloodstream. The Hasselt University team found the particles accumulated on the side of the placenta closest to the fetus, near where the umbilical cord emerges.

And it's a small study. Still, "just finding it at the placenta is important," Sadovsky said. "The next question would be how much of these black carbon particles need to be there to cause damage."

Scientists already had some clues from animal studies that particles could reach the placenta, but Tuesday's study is a first with human placentas. The Belgian researchers developed a way to scan placenta samples using ultra-short pulses from a laser that made the black carbon particles flash a bright white light, so they could be measured.

The researchers included placentas from 10 mothers who lived in areas with high pollution and 10 others from low areas. The higher the exposure to pollution, the more particles the researchers counted in the placentas.

Leave a Reply

Your email address will not be published.