Longitudinal effects of prenatal exposure to plastic-derived chemicals and their metabolites on asthma and lung function from childhood into adulthood

Abstract

Background and objective: Environmental exposure to phthalates and bisphenol A (BPA), chemicals used in the production of plastics, may increase risk for asthma and allergies. However, little is known about the long-term effects of early life exposure to these compounds. We investigated if prenatal exposure to these compounds was associated with asthma, allergy and lung function outcomes from early childhood into adulthood in a cohort study.

Methods: Maternal serum samples collected from 846 pregnant women in the Raine Study were assayed for BPA and phthalate metabolites. The children of these women were followed up at 5, 13 and 22 years where spirometry and respiratory questionnaires were conducted to determine asthma and allergy status. Lung function trajectories were derived from longitudinal spirometry measurements. Multinomial logistic regression and weighted quantile sum regression was used to test associations of individual and chemical mixtures with asthma phenotypes and lung function trajectories.

Results: Effects of prenatal BPA and phthalates on asthma phenotypes were seen in male offspring, where BPA was associated with increased risk for persistent asthma, while mono-iso-butyl phthalate and mono-iso-decyl phthalate was associated with increased risk for adult asthma. Prenatal BPA had no effect on lung function trajectories, but prenatal phthalate exposure was associated with improved lung function.

Conclusion: Prenatal BPA exposure was associated with increased likelihood of persistent asthma in males, while prenatal phthalate exposure was associated with increased likelihood of adult asthma in males. Results suggest that prenatal exposure to prenatal BPA and phthalates affect asthma risk, particularly in males, however lung function was not adversely affected.

Keywords: asthma; environmental exposure; longitudinal birth cohort study; lung function; pregnancy; the Raine study.

FIGURE 1

Coefficient estimates from a weighted quantile sum (WQS) regression of the WQS index of phthalate mixtures by asthma phenotype compared with no asthma as the reference group (A), and weights of all measured phthalates metabolites in association with asthma phenotypes (B). Models were adjusted for household income, maternal smoking, breastfeeding status and maternal age.

FIGURE 2

Coefficient estimates from a weighted quantile sum (WQS) regression of the WQS index of phthalate mixtures for FEV₁ (A), FVC (B) and FEV₁/FVC (C) trajectories, and weights of all measured phthalates metabolites in association with FEV₁ (D), FVC (E) and FEV₁/FVC (F) trajectories. All comparisons were made with the average trajectory as the reference group. Models were adjusted for household income, maternal smoking, breastfeeding status and maternal age.