Associations of urinary phthalate metabolite and replacement chemical concentrations with gestational blood pressure

Abstract

Abstract Introduction Some phthalates and their replacements are endocrine disrupting chemicals (EDCs) found in consumer products and linked to hypertensive disorders of pregnancy (HDP). Few studies have evaluated associations between EDCs and gestational blood pressure. Objective To evaluate associations between EDC biomarkers with gestational blood pressure. Methods The Environmental Reproductive and Glucose Outcomes study (N = 338) measured urinary concentrations of 18 phthalate and replacement metabolites and systolic (SBP) and diastolic (DBP) blood pressure at 3 pregnancy study visits (median: 12, 19, and 26 weeks’ gestation). Individual metabolite concentrations and summary measures based on common source or mechanism (eg, ΣPersonal care products [ΣPCP]) were log2-transformed, specific-gravity corrected, and modeled continuously and in quartiles. We estimated covariate-adjusted associations of individual metabolites and, summary measures with blood pressure using linear regression, and with HDP using log-binomial regression, assessing metabolite mixtures using Bayesian Kernel Machine Regression. Results HDP prevalence was 12.7%. Higher concentrations of monoethyl phthalate (MEP) and ΣPCP were most consistently associated with SBP and DBP elevations at visit 3. Higher concentrations of MEP (Q4 vs Q1) were associated with 4.59 mmHg higher SBP (95% CI: 0.04, 9.15), and higher ΣPCP (Q3 vs Q1) were associated with 5.78 mmHg (95% CI: 1.59, 9.97). Higher MEP and ΣPCP (Q4 vs Q1) were positively linked to DBP elevations of 4.51 to 4.70 mmHg. Other phthalate biomarkers were associated with blood pressure at specific time points. Discussion Certain urinary phthalate biomarkers, particularly MEP and ΣPCP, were associated with higher blood pressure levels in pregnancy, with implications for HDP.