How traffic pollution affects children
As the number of vehicles on our roads increase every day, so does pollution related to traffic.
Traffic-related pollution is one of the significant contributing factors to various health problems including increased risk of cardiovascular disease.
Exposure to high levels of pollution affects everyone, including children as a new study reveals that traffic-related pollution affects children and teens at the DNA level.
The findings showed that as exposure to PAHs increased, the length of telomeres decreased.
Children living in highly polluted cities are especially vulnerable to DNA damage of telomeres, due to their physical development as well as their developing immune system.
Telomeres play an important role on chromosome stability and health of body cells and recent studies have shown that exposure to higher levels of traffic- related pollution has led to shortening of telomeres in healthy adults.
As a result it seems viable to use telomere length as a biomarker to understand the effect air pollution has on children and teens.
This study included 14 children and adolescents, aged 11 to 14 years old, living in Fresno, California which is the second most polluted city in the United States. They were part of a larger population of children enrolled in a study on asthma in Fresno.
The scientists analysed the relationship between polycyclic aromatic hydrocarbons (PAHs) and the shortening of telomeres – a type of DNA damage associated with ageing.
PAHs are ubiquitous ambient air pollutants existing both as a gas and particle phases. In urban environments, motor vehicles are the main source of potent PAHs.
The findings showed that as exposure to PAHs increased, the length of telomeres decreased.
Asthma is a chronic inflammatory condition of the airways often characterised by recurring exacerbations which can lead to telomere shortening.
Exposure to high levels of pollutions can trigger such exacerbations and contribute to shortened telomeres.
In this study children and teens with asthma were exposed to higher PAHs than those without asthma.
After making adjustments for asthma and other factors such as age, sex, race and ethnicity, the relationship between pollution and telomere length stayed the same.
Although in this study it was not possible to know whether shortened telomere in children and teens with asthma was due to their asthmatic condition or exposure to high levels of pollution, or both.
This study adds to previous studies on the damaging impact of air pollution which causes oxidative stress leading to damaged lipids, protein and DNA.
Children may have different telomere shortening parameters than adults making them even more vulnerable to the damaging effects of traffic-related pollution.
This study provides insights into the impact of air pollution at the molecular level affecting the youngest citizens of this planet. This knowledge is important to help design interventions and strategies needed to combat such exposure and to keep children safe in an environment which is conducive to their health and wellbeing.
Source: Journal of Occupational and Environmental Medicine
