Exposure to air pollution during pregnancy may cause a child to age prematurely later in life, according to the findings of new research.
In a study published this week in the medical journal JAMA Pediatrics, researchers from Belgium report that infants exposed to air pollution during pregnancy had significantly shorter telomeres, a biomarker of aging, than those who were not exposed to the pollution.
More than 640 mother and child pairs were studied in the Belgium-based Environmental Influence on aging in Early Life Study, an ongoing research project that explores the interaction of human aging and environmental factors, such as pollution.
Women who delivered one child after 37 weeks of pregnancy were recruited for the study between February 2010 and December 2014.
Researchers extracted DNA from the infant’s cord blood and placental tissue. They also used pollution readings from monitoring devices placed at the mother’s address. The devices were specifically calibrated to estimate particulate matter readings for PM 2.5, particulate matter less than 2.5 micrometers in diameters.
Particulate matter is a mixture of tiny air pollution molecules and water molecules. PM 2.5 is roughly 30 times smaller than the average diameter of human hair, which is 70 micrometers.
Mothers who had higher exposure levels to PM 2.5 gave birth to newborns who had significantly lower telomere length. Researchers said the differences could not be explained by other factors, like socioeconomic class, age, or habits like smoking.
Telomeres are the end caps of chromosomes. They are considered a marker of biological aging, shorter telomeres indicate advanced aging. For infants to have shorter telomeres is rather abnormal, as telomeres begin to shorten as a person ages.
Researchers concluded that infants who had an increase of 5-μg/m3 of PM 2.5 had 9% shorter cord blood telomeres and 13% shorter placental telomeres.
The study also indicated the second trimester was an especially important time which affected the infants health and telomere length.
Researchers said the study may indicate pre-birth exposure to air pollution may have a lasting impact on the health of a person later in life.
Prenatal air pollution exposure may have serious health consequences as improved air quality may promote “molecular longevity from birth.”
A recent World Health Organization report indicated 90% of the world’s population live in areas with poor air quality. Another recent study indicated air pollution may increase Latino children’s risk of diabetes. Other studies on telomere length have shown the shortening may affect cardiovascular disease risk and longevity.