Exposure to a Mixture of Endocrine-Disrupting Chemicals and Metabolic Outcomes in Belgian Adolescents

Childhood exposure to endocrine-disrupting chemicals (EDCs), either alone or in mixtures, may affect metabolic outcomes, yet existing evidence remains inconclusive. In our study of 372 adolescents from the Flemish Environment and Health Study (FLEHS IV, 2017–2018), we measured 40 known and suspected EDCs and assessed metabolic outcomes, including body mass index z-score (zBMI), abdominal obesity (AO), total cholesterol (TC), and triglycerides (TG). We applied Bayesian kernel machine regression (BKMR) and Bayesian penalized horseshoe regression for variable selection and then built multivariate generalized propensity score (mvGPS) models to provide an overview of the effects of selected EDCs on metabolic outcomes. As a result, BKMR and horseshoe together identified five EDCs associated with zBMI, three with AO, three with TC, and five with TG. Through mvGPS analysis, monoiso-butyl phthalate (MIBP), polychlorinated biphenyl (PCB-170), and hexachlorobenzene (HCB) each showed an inverse association with zBMI, as did PCB-170 with AO. Copper (Cu) was associated with higher TC and TG, except in boys where it was linked to lower TG. Additionally, monoethyl phthalate (MEP) and monobenzyl phthalate (MBzP) were associated with higher TG. To conclude, our findings support the association between certain chemicals (Cu, MEP, and MBzP) and elevated lipid levels, aligning with prior studies. Further investigation is needed for sex-specific effects

Fully-adjusted association between RF-EMF exposure sources and those sleeping problems <i>a priori</i> hypothesized to be potentially related to RF-EMF exposure.

<p>Model adjusted for maternal educational level, parental financial situation, parental countries of birth, maternal and paternal age, and child's sex, age, and number of siblings</p><p>Fully-adjusted association between RF-EMF exposure sources and those sleeping problems <i>a priori</i> hypothesized to be potentially related to RF-EMF exposure.</p

Maternal, paternal, and child characteristics by mobile and cordless phone use.

<p>^aValues are percentages for the categorical variables and arithmetic means for the continuous variables</p><p>P-trend = P-value for trend</p><p>Overall sleep scores are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0139869#pone.0139869.t003" target="_blank">Table 3</a>. On average, children went to bed at around 8pm and woke up shortly before 7am.</p><p>Maternal, paternal, and child characteristics by mobile and cordless phone use.</p

Maternal, paternal, and child characteristics by RF-EMF^a.

<p>^aValues are percentages for the categorical variables and arithmetic means for the continuous variables</p><p>CP: Cordless phone; P-diff = P-value for group differences based on chi-square or Kruskal-Wallis tests; P-trend = P-value for non-parametric test for trend</p><p>Maternal, paternal, and child characteristics by RF-EMF<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0139869#t001fn001" target="_blank">^a</a>.</p

Fully-adjusted association between RF-EMF exposure sources and those sleeping problems <i>a priori</i> hypothesized NOT to be potentially related to RF-EMF exposure.

<p>Model adjusted for maternal educational level, parental financial situation, parental countries of birth, maternal and paternal age, and child's sex, age, and number of siblings.</p><p>Fully-adjusted association between RF-EMF exposure sources and those sleeping problems <i>a priori</i> hypothesized NOT to be potentially related to RF-EMF exposure.</p

Sleep scores.

<p>Sleep scores.</p

Selected characteristics of cases and controls.

<p>Selected characteristics of cases and controls.</p

Descriptive statistics for the distribution of the ln(OR)s of lung cancer for the 129 selected occupations (3-digit ISCO codes; n>10) obtained using Maximum Likelihood (ML), Semi-Bayes adjustment towards the global mean (SB) and hierarchical regression (HR).

a<p>A 7-fold range means that we assume <i>a priori</i> that 95% of the true ORs are within a 7-fold range of each other (e.g. from 0.5 to 3.5).</p>b<p>Prior range of ORs’ variation when matrix is the Identity matrix. A 20, 10, 5, or 2.5-fold range means that we have 95% <i>a priori</i> certainty that the residual OR for being ever employed in an occupation after accounting for the effect of the carcinogens will lie within a 20, 10, 5 or 2,5-fold range.</p

Relationship between the ORs obtained with the different approaches.

<p>Scatter plots of the ORs of lung cancer for the 129 selected occupations estimated using hierarchical regression (HR) with =0.76 <i>vs</i>. Maximum Likelihood (ML) (A), HR with =0.59 <i>vs</i>. ML (B), HR with =0.23 <i>vs</i>. ML (C) and Semi-Bayes adjustment towards the global mean (SB) <i>vs.</i> ML (D).</p

ORs of lung cancer and 95% confidence intervals obtained using Maximum Likelihood (ML), Semi-Bayes adjustment towards the global mean (SB) and hierarchical regression (HR) for the occupations associated with the twenty highest ORs in the conventional ML analysis.

a<p>ASB=Asbestos (0=no exposure, 1=low exposure, 2=high exposure), CR=Chromium (0=no exposure, 1=low exposure, 2=high exposure), SI=Silica (0=no exposure, 1=low exposure, 2=high exposure).</p