Prenatal Exposure to Phthalates and Childhood Body Size in an Urban Cohort

Abstract

Background:Phthalate exposures are hypothesized to increase obesity; however, prior research has been largely cross-sectional.Objective:We evaluated associations between prenatal phthalate exposures and body mass index (BMI) at child ages 5 and 7 years.Methods:Nine metabolites of six phthalates—di(2-ethylhexyl) phthalate (DEHP), di-n-octyl-, di-iso-butyl-, di-n-butyl-, butylbenzyl-, and diethyl phthalates—were measured in spot urine samples collected from pregnant African-American and Dominican women during their third trimester, and from their children at ages 3 and 5 years. To reduce multiple comparison issues, we initially used principal component analysis (PCA) to identify major patterns of natural log (ln)-transformed metabolite concentrations. Height and weight were assessed at ages 5 and 7 years, and fat mass and waist circumference at age 7. Linearized generalized estimating equation analyses related maternal component scores to child anthropometric outcomes at ages 5 (n = 326) and 7 (n = 330) years.Results:PCA identified a DEHP component and a non-DEHP component. In boys, higher maternal non-DEHP, but not DEHP, component scores were associated with lower BMI z-score (β = –0.30; 95% CI: –0.50, –0.10, n = 156), lower fat percentage (β = –1.62; 95% CI: –2.91, –0.34, n = 142), and smaller waist circumference (β = –2.02; 95% CI: –3.71, –0.32, n = 124). No significant associations with anthropometric outcomes were seen in girls (for BMI z-score, β = 0.07; 95% CI: –0.18, 0.31, n = 181). Interactions between sex and non-DEHP component association with outcomes were statistically significant (p < 0.01).Conclusions:Contrary to hypotheses, prenatal non-DEHP phthalate exposures were associated with lower BMI z-score, waist circumference, and fat mass in boys during early childhood.Citation:Maresca MM, Hoepner LA, Hassoun A, Oberfield SE, Mooney SJ, Calafat AM, Ramirez J, Freyer G, Perera FP, Whyatt RM, Rundle AG. 2016. Prenatal exposure to phthalates and childhood body size in an urban cohort. Environ Health Perspect 124:514–520; http://dx.doi.org/10.1289/ehp.1408750

Prenatal phthalate biomarker concentrations and performance on the Bayley Scales of Infant Development-II in a population of young urban children

“…Figure 1 provides comparisons of our results with two such studies, including Tellez-Rojo et al who investigated prenatal phthalate exposure in relation to performance on the BSID-II among 135 children ages 2 to 3 years living in Mexico City between 1997 and 2003, and Whyatt et al who investigated this association among 319 children at approximately 3 years of age living in New York City between 1996 and 2006 (Figure 1) (Whyatt et al 2012; Tellez-Rojo et al 2013). The implications of these differences in associations among boys and girls are unclear, but are echoed in sexually dimorphic associations across a range of outcomes in relation to phthalate exposure, including anogenital distance (Swan et al 2015), behavior (Engel et al 2010; Swan et al 2010; Kobrosly et al 2014; Swan et al 2015), and growth (Valvi et al 2015; Kim et al 2016; Buckley et al 2016; Maresca et al 2015). Additional experimental evidence would improve our understanding of how phthalates might influence sexually dimorphic neurologic development in human populations, although plausible biological mechanisms have been noted (Miodovnik et al 2011).…”

Early-life exposure to EDCs: role in childhood obesity and neurodevelopment

“…70–72 One publication reported that prenatal DEHP exposure is associated with decreased body mass index (BMI) in boys and increased BMI in girls, 70 whereas another publication found that non-DEHP phthalate exposures were associated with decreased BMI in boys, but not girls. 71 A third publication did not report any association between prenatal phthalate exposure and childhood adiposity. 72 In a pooled cohort including US participants from two of the previously mentioned cohort studies, increasing maternal urinary mono-3-carboxypropyl phthalate concentrations during pregnancy were associated with a doubling in the risk of being overweight or obese (95% CI: 1.2, 4.0).…”

“…71,96–98 Three of these reported that childhood exposure to DEP was associated with excess adiposity and increased prevalence of obesity or excess adiposity, 98 but another did not. 71 In a prospective cohort of over 1,000 US girls, higher DEP exposure at 6–8 years of age was associated with increased BMI scores and waist circumference at 7–13 years of age. 97 In a cross-sectional study of US children, increasing urine concentrations of low molecular weight phthalates was associated with a 22% increase in the prevalence of obesity.…”

Metabolism disrupting chemicals and metabolic disorders

“…Prenatal TBT exposure permanently alters MSC cell fate in both males and females and caused hepatic steatosis and altered hepatic gene expression in both males and females through the F3 generation. Skinner and colleagues have similarly shown that plastic components such as BPA, DEHP, dibutyl phthalate [358], a mixed hydrocarbon mixture (jet fuel JP-8) [358], and DDT [358] all lead to a transgenerational predisposition to obesity in the F3 generation. The molecular mechanisms remain unclear; however, many of the toxicants work through nuclear receptors [611] that are likely linked to epigenetic changes [613, 614] that likely play a significant role in the transgenerational effects.…”