Breathing in polluted air from vehicles results in DNA damage in children and teenagers, suggests a new study published in the Journal of Occupational and Environmental Medicine.
The adverse effects of air pollution can reach into the DNA, says new research conducted by scientists from the US. It appears that high levels of air pollutants coming from traffic vehicles are linked with a type of DNA damage whereby the end of chromosomes are reduced in size, a process called telomere shortening. Interestingly, previous research links the same type of DNA damage to asthma in young people, explains study author John R. Balme, from the University of California, Berkeley.
It is to be noted that the shortening of telomeres (the structures at the end of chromosomes) is also associated with ageing: as one ages, one’s telomeres naturally decrease in size, making it a biomarker for ageing. The process might ultimately also be considered as a biomarker of DNA damage caused by environmental conditions and/or chronic inflammation, explain the authors.
Balme and colleagues focused on a common group of air pollutants, polycyclic aromatic hydrocarbons (PAHs), whose source is motor vehicle exhaust, and their effects on telomere shortening. They studied the possibility of a potential link between the two in children and teenagers residing in Fresno, a city notorious for its high level of air pollution in the US.
The findings show that telomere length decreases as exposure to PAHs increases. When the researchers ruled out other factors related to telomere length such as asthma, age, and race, they found that the link between telomere shortening and PAH levels remained significant.
The new study supports previous ones that suggest air pollution leads to a process called oxidative stress which can damage DNA, and other molecules like lipids and proteins.
Why are children more vulnerable than adults? The study authors suggest that the former’s telomere length regulation might be different from adults such that the structure is more prone to damage.
This research promises to bring positive change.
“Greater knowledge of the impact of air pollution at the molecular level is necessary to design effective interventions and policies,” conclude the researchers.