pollutionThe air pollution caused by vehicles may be resulting in telomere shortening in children and teenagers, according to new research. The study, published in the Journal of Occupational and Environmental Medicine, investigated how telomere damage may act as a biomarker for environmental damage to DNA.

Fresno, a city of around 520,000 people in California, is the third-most polluted city in the United States, according to a recent report by the American Lung Association (behind Bakersfield, CA and Visalia, CA). Part of this pollution is made up of polycyclic aromatic hydrocarbons (PAHs), which are released into the atmosphere as exhaust fumes from motor vehicles and which are known to be harmful to human health.

Telomeres are ‘caps’ on the end of chromosomes that protect the genetic material during the cell cycle. Previous research has demonstrated that the length of these telomeres decreases over time and they do not regenerate, indicating that they can be used to monitor the aging process of cells. Several studies have been conducted to investigate the effects of environmental factors like smoking have on the length of telomeres.

In this study, researchers investigated the length of telomeres in 14 participants between 11 and18 years old who were living in Fresno. The participants ranged from high- to low-exposure groups and were selected from a larger study of asthma in children (some with asthma and some without).

Their results demonstrated that when the children endured higher exposure to PAHs, their telomeres were proportionally shortened (a linear relationship), indicating greater DNA damage. This relationship remained significant after the results were normalised to account for asthma, gender, age, and ethnicity. The results support the theory that pollutants in the atmosphere cause oxidative stress in cells, which can result in damage to proteins, lipids, and DNA.

As a preliminary study, the scope of the investigation was narrow and only worked with a small number of participants, but the initial results indicate that further studies may be able to help us better understand the adverse health outcomes associated with pollution.

The authors, researchers from the University of California, concluded, “Our pilot study results suggest that telomere shortening in children may be associated with exposure to traffic-related air pollution. Greater knowledge of the impact of air pollution at the molecular level is necessary to design effective interventions and policies. Our preliminary data will inform the design of a larger study to examine the hypothesis generated from these results.”

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