Researchers from the University of California, Berkeley have found evidence that air pollution from traffic damages and shortens a region of our DNA called telomeres.
Telomeres are basically protein endcaps found at the end of our chromosomes. Researchers say that the length of the caps generally measure our biological clocks – the longer the telomere, the younger someone is biologically regardless of their actual age. Having a shorter telomere, which the researchers suggest air pollution causes, would indicate advanced biological aging that could result in variety of health problems over time.
"Our results suggest that telomere length may have potential for use as a biomarker of DNA damage due to environmental exposures and/or chronic inflammation," the researchers said.
Especially harmful to children and young people
The study analyzed the relationship between polycyclic aromatic hydrocarbons (PAHs), a pervasive air pollutant found in motor vehicle exhaust, and telomere length in fourteen children from Fresno, Calif. – the second-most polluted U.S. city.
The results showed that participants’ who had more exposure to PAHs had shorter telomere lengths, even after adjusting for factors like age, sex, race/ethnicity, and presence of asthma. The researchers theorize that the PAHs from vehicle exhaust cause oxidative stress that damages lipids, proteins, and DNA and ultimately leads to telomere shortening.
The researchers further note that telomere shortening could be especially harmful to children and young consumers because their bodies operate under different internal regulations. They say that younger people may become more vulnerable to air pollution and its negative health effects over time when compared to older consumers.
Informing new policies
The researchers believe their work could help lawmakers design and implement interventions and policies that could reduce air pollution and PAHs. They say the data they collected will be used as part of a larger study that should corroborate their findings.
"Greater knowledge of the impact of air pollution at the molecular level is necessary to design effective interventions and policies," said co-author Dr. John R. Balmes.
The full study has been published in the Journal of Occupational and Environmental Medicine.