Systematic review on the adverse effects of traffic related air pollution on respiratory health in children

Abstract

Objectives : To investigate the impacts of traffic related air pollution (TRAP) on children’s respiratory health, and to investigate the policies and regulations implemented in other countries and the suggestions from the World Health Organization (WHO) to tackle this problem.

Methods and Results: Using relevant keywords, 122 articles were acquired from PubMed and 15 were from MEDLINE via EBSCO host respectively. The articles were published between 1980 to 2013; all of which had examined the impacts of TRAP on children’s respiratory health. After assessing inclusion and exclusion criteria, 9 articles were finally included in this systematic review. Differences in demographic characteristics were studied and compared to determine the association between TRAP exposure and respiratory health impacts on children aged between 1 and 18. Four cross-section surveys and five cohort studies were selected in this review. The association between TRAP exposure and differences in children’s respiratory impacts were demonstrated in all studies. Multiple outcome measures were used to examine changes of children’s respiratory health such as the decline in lung function, incidences of asthma and inflammatory responses. There were 4 out of 9 articles suggesting the decline in lung function was related to TRAP exposure; 5 out of 9 articles showed the relationships between incidences of asthma and inflammatory responses and TRAP exposure and 2 articles mentioned other respiratory symptoms; notably, wheezing and sneezing, runny and stuffed nose. This review finally summarized the results of selected articles stressing that children who lived close to roadway within a 500 meter radius from home, with an early exposure to air pollution in the first year of age and a frequent exposure to heavy road traffic and outdoor air pollutants would experience greater impacts on respiratory health.

Conclusion: The positive association between the impacts on children’s respiratory health and TRAP exposure has been determined through this systematic review. Stricter emission control strategies and updated guidelines are required to regulate traffic emission and improve air quality in order to reduce harm and provide a better living environment for our next generations.