Traffic-related air pollution and obesity formation in children: a longitudinal, multilevel analysis

Abstract

BackgroundBiologically plausible mechanisms link traffic-related air pollution to metabolic disorders and potentially to obesity. Here we sought to determine whether traffic density and traffic-related air pollution were positively associated with growth in body mass index (BMI = kg/m2) in children aged 5–11 years.MethodsParticipants were drawn from a prospective cohort of children who lived in 13 communities across Southern California (N = 4550). Children were enrolled while attending kindergarten and first grade and followed for 4 years, with height and weight measured annually. Dispersion models were used to estimate exposure to traffic-related air pollution. Multilevel models were used to estimate and test traffic density and traffic pollution related to BMI growth. Data were collected between 2002–2010 and analyzed in 2011–12.ResultsTraffic pollution was positively associated with growth in BMI and was robust to adjustment for many confounders. The effect size in the adjusted model indicated about a 13.6% increase in annual BMI growth when comparing the lowest to the highest tenth percentile of air pollution exposure, which resulted in an increase of nearly 0.4 BMI units on attained BMI at age 10. Traffic density also had a positive association with BMI growth, but this effect was less robust in multivariate models.ConclusionsTraffic pollution was positively associated with growth in BMI in children aged 5–11 years. Traffic pollution may be controlled via emission restrictions; changes in land use that promote jobs-housing balance and use of public transit and hence reduce vehicle miles traveled; promotion of zero emissions vehicles; transit and car-sharing programs; or by limiting high pollution traffic, such as diesel trucks, from residential areas or places where children play outdoors, such as schools and parks. These measures may have beneficial effects in terms of reduced obesity formation in children.

Chemical and non-chemical stressors affecting childhood obesity: a systematic scoping review

“…162 Prenatal air pollution exposures (PAHs, NO x , CO, PM) associated with birthweight have found either no associations or low birthweight, except for one report by Rundle et al, where prenatal exposures to PAHs were associated with obesity at age 7 years. 160,161,[163][164][165][166][167][168][169][170] Jerrett et al 162,171 examined the relationship between BMI levels in children and traffic density, air pollutants, and proximity of roadways to residential areas. In both studies, exposure to air pollutants resulted in increased BMI levels.…”

Long-path measurements of pollutants and micrometeorology over Highway 401 in Toronto

“…Studies in Toronto have shown that exposure to traffic-related air pollution is associated with respiratory conditions (Buckeridge et al, 2002), increased risk of circulatory mortality (Jerrett et al, 2009), cardiovascular mortality (Chen et al, 2013), ischemic heart disease (Beckerman et al, 2012), and childhood atopic asthma (Shankardass et al, 2015). Research results in other locations have also shown associated negative health effects, such as asthma (Lin et al, 2002;McConnell et al, 2006), cancer and leukemia (Pearson et al, 2000) in children, and development of obesity in children (Jerrett et al, 2014). Exposure to traffic-related air pollution may also be associated with increased risk of dementia.…”

Sex-specific difference of the association between ambient air pollution and the prevalence of obesity in Chinese adults from a high pollution range area: 33 Communities Chinese Health Study

“…Three papers were derived from the Children's Health Study, a longitudinal survey conducted in 13 communities across Southern California in United States. Jerrett et al (2014) examined correlations among traffic density and traffic-related air pollution with increases in BMI in 4550 children aged 5e11 years. A 13.6% increase in annual BMI growth when comparing the highest to lowest tenth percentile of air pollution exposure was found, which resulted in an increase of nearly 0.4 BMI units on attained BMI at age 10.…”

“…Rundle et al (2012) found that maternal exposure to air polycyclic aromatic hydrocarbons (PAH) during pregnancy is positively correlated with increased body mass index (BMI) and obesity by age seven in children. A more recent study suggested that exposure to near-roadway pollution is also a contributing factor in the development of childhood obesity (Jerrett et al, 2014). Experimental evidence has revealed that ambient particle (diameter, <2.5 mm [PM 2.5 ]) exposure is capable of inducing metabolic abnormalities and obesity in non-human subjects (rodents) (Xu et al, 2010).…”