Children and teenagers exposed to high levels of traffic pollution were found to show signs of premature ageing, according to the new study.
Researchers in California, United States (U.S.), also found youngsters with asthma had higher levels of a pollutant caused by motor vehicle exhaust, Guardian Nigeria reports.
Those with higher levels had a specific type of Deoxyribonucleic Acid (DNA)/genetic material damage called telomere shortening – the main cause of age-related breakdown of our cells.
Telomeres are vital to our health – they can be described as the caps at the end of each strand of DNA that protect our chromosomes, like the plastic tips at the end of shoelaces.
“Children may be especially vulnerable to the effects of telomeric DNA damage due to their physical development as well as developing the immune system,” wrote Dr John Balmes from the University of California, Berkeley, and his colleagues who carried out the study published in the Journal of Occupational and Environmental Medicine.
The new preliminary study suggests telomeres may be the key to understanding how pollution exposure leads to adverse health outcomes.
The researchers assessed the relationship between a ‘ubiquitous’ motor vehicle exhaust air pollutant called polycyclic aromatic hydrocarbons (PAHs), and shortening of telomeres.
As the exposure to PAHs increased, telomere length decreased. Children and teenagers with asthma were exposed to higher PAH levels than those without asthma.
The relationship between PAH level and telomere shortening remained significant after adjustments for asthma and other factors (age, sex, and race/ethnicity) were made.
Previous studies suggest that telomere length is linked to progression in chronic obstructive pulmonary disease (COPD). It also suggests that children may have ‘different telomere shortening regulation than adults’ – which might make them more vulnerable to the damaging effects of air pollution.
Meanwhile, previous research has shown that telomeres are shortened as we age, but telomeres can also be shortened by stress, smoking, obesity, lack of exercise and a poor diet.