A Cross-sectional Study of Brownfields and Birth Defects

Abstract

BACKGROUND AND AIM: The term brownfield is used to denote a multitude of abandoned and disused sites, spanning many former purposes. Brownfields represent a heterogenous yet ubiquitous exposure for many Americans, which may contain hazardous waste and represent urban blight. Neonates and pregnant individuals are often sensitive to subtle environmental exposures. For this reason, we conducted a study evaluating if residential brownfield exposure was associated with birth defects. METHODS: Using North Carolina birth records from 2003-2015 we sampled 753,195 births, identifying 37,758 defects across 29 different birth defect phenotypes. Due to the rarity of some birth defects we also examined several defect groups. Number of brownfields within a 2000m buffer of the residential address at birth was summed. We utilized multivariable logistic regression models adjusted for multiple demographic and environmental covariates available from birth records, 2010 Census, and EPA’s environmental quality index to calculate odds ratios (OR) and 95% confidence intervals (CI). RESULTS:While we observed null associations for most individual defects, associations with Atrial Septal defect (ASD) and Ventricular Septal defect (VSD) were positive (OR 1.12; 95%CI 1.05-1.19 and OR 1.14; 95%CI 1.02-1.27, respectively). We observed an inverse association with gastroschisis (OR 0.72; 95%CI 0.56-0.92). We found null associations for central nervous, orofacial, urinary, and chromosomal defect groups, and positive associations for cardiovascular and external defect groups (OR 1.09; 95%CI 1.04-1.15 and OR 1.15; 95%CI 1.00-1.33, respectively). Additional analyses indicated an exposure-response relationship for several defects (i.e. ASD, VSD, and the cardiovascular defect group), where the magnitude of the OR increased as the number of brownfields in the 2000m buffer increased. CONCLUSIONS:There is some indication that residential proximity to brownfields is associated with birth defects, especially cardiovascular defects. More tailored adjustment schemes and in-depth analyses of individual defects may reveal additional novel associations. This abstract does not reflect EPA policy. KEYWORDS: birth outcomes, built environment, hazardous waste