Prenatal and Childhood Traffic-Related Air Pollution Exposure and Telomere Length in European Children: The HELIX Project.

Abstract

Background:Telomere length is a molecular marker of biological aging.Objective:Here we investigated whether early-life exposure to residential air pollution was associated with leukocyte telomere length (LTL) at 8 y of age.Methods:In a multicenter European birth cohort study, HELIX (Human Early Life Exposome) (), we estimated prenatal and 1-y childhood exposure to nitrogen dioxide (), particulate matter with aerodynamic diameter (), and proximity to major roads. Average relative LTL was measured using quantitative real-time polymerase chain reaction (qPCR). Effect estimates of the association between LTL and prenatal, 1-y childhood air pollution, and proximity to major roads were calculated using multiple linear mixed models with a random cohort effect and adjusted for relevant covariates.Results:LTL was inversely associated with prenatal and 1-y childhood and exposures levels. Each standard deviation (SD) increase in prenatal was associated with a (95% CI: , ) change in LTL. Prenatal was nonsignificantly associated with LTL ( per SD increase; 95% CI: , 0.6). For each SD increment in 1-y childhood and exposure, LTL shortened by (95% CI: , ) and (95% CI: , 0.1), respectively. Each doubling in residential distance to nearest major road during childhood was associated with a 1.6% (95% CI: 0.02, 3.1) lengthening in LTL.Conclusion:Lower exposures to air pollution during pregnancy and childhood were associated with longer telomeres in European children at 8 y of age. These results suggest that reductions in traffic-related air pollution may promote molecular longevity, as exemplified by telomere length, from early life onward. https://doi.org/10.1289/EHP4148