Air pollution is known to be harmful to everyone, but a new study found that it's particularly dangerous to the youth. Children and teens exposed to traffic-related pollution are found to be prone to DNA damage called telomere shortening.

Telomeres are a section of repetitive DNA at the end of the chromosome, protecting this edge from deterioration, a report from News Medical revealed. They function much like the tips at the end of a shoelace, which keeps the entire lace from fraying. Shortening of telomeres - which happens naturally with aging - has been found to be linked to a number of age-related diseases.

According to a report from Science Daily, preliminary research has shown that young people with asthma also show signs of telomere shortening. The new study included 14 children children and adolescents living in Fresno, California, which is known to be the second most polluted city in the entire United States.

The researchers analyzed the relationship between telomere shortening and polycyclic aromatic hydrocarbons (PAHs), which is a pervasive air pollutant from motor vehicle exhaust. They found that as the exposure to PAHs increased, the telomere length decreased.

Those who are afflicted with asthma were found to be exposed to higher PAH levels than those who are not. The connection between PAH exposure and telomere shortening remained even when the researchers adjusted the data to consider asthma and other factors related to telomere length such as age, sex and ethnicity.

Children have been suggested to have different telomere shortening regulation than adults, so they are often more vulnerable to the dangers of air pollution than older people with similar exposure.

"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 wrote in the paper.

The study was published in the Journal of Occupational and Environmental Medicine.