Air pollution linked to newborns with shortened telomeres

Our DNA contains specialized sections known as telomeres, which allow chromosomes to be accurately copied during cell division. As our cells divide over time, our telomeres shorten, which results in a gradual loss of genomic stability. Loss of telomere length has been linked to cancer, heart disease, cognitive decline, aging, and premature death. Needless to say, maintaining longer telomere length is likely to be important to our overall health.

A study from Columbia University’s Mailman School of Public Health has found that air pollution may shorten telomere length in newborns. The research team analyzed telomere length in the umbilical cord blood of 255 newborns. Half of the newborns were born before the closure of a coal-burning plant in Tongliang, China in 2004, while the other half were conceived and born after.

High levels of air pollution in Tongliang resulted in the government shutting down the local coal-burning power plant in 2004 in an effort to improve community health.

The study’s findings showed that babies born pre-closure had higher levels of PAH-DNA cord adducts, which is a biomarker for exposure to polycyclic aromatic hydrocarbons. These hydrocarbons are a toxic component of air pollution from coal plants. Increased levels of these adducts in cord blood were linked to shorter telomeres, as well as lower levels of brain-derived neurotropic factor (BDNF) – a protein involved in neuronal growth.

“An individual’s telomere length at birth is known to influence their risk for disease decades later during adulthood,” says Deliang Tang, professor of Environmental Health Sciences at the Mailman School. “Further follow-up is needed to assess the role telomere length plays in health outcomes in the context of early life exposure to air pollution.”

The researchers did not find any association between telomere length and developmental score in the 210 children they tested at age 2. However, they stress that this finding does not rule out telomere length-related neurodevelopmental problems as the children age. In previously published research, the authors found that newborns born after the plant closure had lower levels of PAH-DNA adducts, lower rates of various health outcomes, and increased levels of BDNF.

“The new study adds to the evidence that closing this coal-burning power plant was beneficial to the health and future well-being of newborns there,” says Frederica Perera, director of the Columbia Center for Children’s Environmental Health and a professor of Environmental Health Sciences at the Mailman School. “Moreover, we know that lowering exposure to air pollution anywhere will be beneficial to children’s health and long-term potential.”

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By Connor Ertz, Earth.com Staff Writer