Exposure to Air Pollution during Pregnancy and Childhood, and White Matter Microstructure in Preadolescents

Abstract

Background: Air pollution has been related to brain structural alterations, but a relationship with white matter microstructure is unclear.

Objectives: We assessed whether pregnancy and childhood exposures to air pollution are related to white matter microstructure in preadolescents.

Methods: We used data of 2,954 children from the Generation R Study, a population-based birth cohort from Rotterdam, Netherlands (2002-2006). Concentrations of 17 air pollutants including nitrogen oxides (${\mathrm{NO}}_X$), particulate matter (PM), and components of PM were estimated at participants' homes during pregnancy and childhood using land-use regression models. Diffusion tensor images were obtained at child's 9-12 years of age, and fractional anisotropy (FA) and mean diffusivity (MD) were computed. We performed linear regressions adjusting for socioeconomic and lifestyle characteristics. Single-pollutant analyses were followed by multipollutant analyses using the Deletion/Substitution/Addition (DSA) algorithm.

Results: In the single-pollutant analyses, higher concentrations of several air pollutants during pregnancy or childhood were associated with significantly lower FA or higher MD ($p<0.05$). In multipollutant models of pregnancy exposures selected by DSA, higher concentration of fine particles was associated with significantly lower FA [$-0.71$ (95% CI: $-1.26$, $-0.16$) per $5{\mu g/m}^3$ fine particles] and higher concentration of elemental silicon with significantly higher MD [0.06 (95% CI: 0.01, 0.11) per $100{\text{ng}/m}^3$ silicon]. Multipollutant models of childhood exposures selected by DSA indicated significant associations of ${\mathrm{NO}}_X$ with FA [$-0.14$ (95% CI: $-0.23$, $-0.04$) per $20{\text{-}\mu g/m}^3$ ${\mathrm{NO}}_X$ increase], and of elemental zinc and the oxidative potential of PM with MD [0.03 (95% CI: 0.01, 0.04) per $10{\text{-ng}/m}^3$ zinc increase and 0.07 (95% CI: 0.00, 0.44) per $1{\text{-nmol}\text{DTT}/\text{min}/m}^3$ oxidative potential increase]. Mutually adjusted models of significant exposures during pregnancy and childhood indicated significant associations of silicon during pregnancy, and zinc during childhood, with MD.

Discussion: Exposure in pregnancy and childhood to air pollutants from tailpipe and non-tailpipe emissions were associated with lower FA and higher MD in white matter of preadolescents. https://doi.org/10.1289/EHP4709.