Prenatal exposure to persistent organic pollutants and markers of obesity and cardiometabolic risk in Spanish adolescents

Hidden link between endocrine-disrupting chemicals and pediatric obesity

The increasing prevalence of pediatric obesity has emerged as a significant public health concern. Among various contributing factors, exposure to endocrine-disrupting chemicals (EDCs) has gained recognition for its potential role. EDCs, including bisphenols, phthalates, per- and polyfluoroalkyl substances, polycyclic aromatic hydrocarbons, and organochlorines, disrupt hormonal regulation and metabolic processes, contributing to alterations in fat storage, appetite regulation, and insulin sensitivity. This study offers a comprehensive review of the current research linking EDC exposure to pediatric obesity by integrating the findings from experimental and epidemiological studies. It also addresses the complexities of interpreting this evidence in the context of public health, highlighting the urgent need for further research.

Influence of prenatal hexachlorobenzene, PCB and selenium levels on growth trajectories in the first year of life: Findings from the NEHO birth cohort

Prenatal exposure to endocrine-disrupting chemicals (EDCs) may impact postnatal growth trajectories, increasing the risk of various diseases later in life. This issue is of particular concern in industrially contaminated areas, where environmental matrices contain mixtures of pollutants. This study aimed to evaluate the associations between cord serum concentrations of organochlorine pollutants (hexachlorobenzene-HCB and polychlorinated biphenyls-PCBs) and essential elements (EEs), and weight growth trajectories during the first year of life. We analyzed data from 237 infants enrolled in the Neonatal Environment and Health Outcomes (NEHO) cohort. Using the Group-Based Multivariate Trajectory modeling approach, we identified three distinct growth trajectories from birth to 12 months, classified as "Higher," "Normal," and "Lower." Multinomial regression models were then applied to the whole sample and stratified by sex to assess the associations between individual exposures and the identified child growth trajectories. HCB exposure was associated with an increased risk of reduced growth during the first year of life in both the overall sample and among males [higher vs normal: ORMale = 0.33 (95 % CIMale:0.12;0.87); lower vs normal: ORMale = 2.17 (95 % CIMale:0.94;5.00)]. Conversely, PCB-180 exposure was linked to higher growth only in females [higher vs normal: ORFemale = 24.10 (95 % CIFemale:1.33;438.24)]. Elevated levels of selenium in cord serum were negatively associated with excessive growth [higher vs normal: OROverall = 0.50 (95 % CIOverall: 0.26;0.97)]. These findings suggest sex-specific effects on the growth profile during the first year of life, with different chemical exposures contributing to different outcomes.

Prenatal exposure to persistent organic pollutants and its impact on the ovarian reserve at 12 years old in the PELAGIE mother-child cohort

Although the ovarian reserve is constituted in utero, the literature on the effects of persistent organic pollutants (POPs) during this vulnerable period on the ovarian reserve later in life is limited. We investigated whether cord blood concentrations of POPs were associated with decreased anti-Müllerian hormone (AMH, a marker of the ovarian reserve) levels in girls at the age of 12. We included 239 girls from the French mother-child PELAGIE cohort. POP concentrations of 14 organochlorine pesticides, 17 polychlorinated biphenyls (PCBs), 5 polybrominated diphenyl ethers, and 9 per-polyfluoroalkyl substances were measured on cord blood sampled at birth. During a follow-up study at 12 years old, blood samples were collected to measure AMH levels. Single-exposure associations were examined with multivariable linear regression models adjusted a priori for potential confounders. Stratification on menarche status was also performed. Mixture effects were investigated using quantile g-computation and Bayesian kernel machine regression. Overall, 16 POPs were measured in at least 30% of samples. No significant associations were found in multivariable linear regressions, except for the third tercile of exposure to PCB 180 which was statistically significantly associated with an increase in AMH levels at 12 years old (Tercile 2 v. Tercile 1: 0.13 ng/mL, 95% CI = -0.29, 0.56; Tercile 3 v. Tercile 1: 0.51 ng/mL, 95% CI = 0.02, 0.99). Additionally, in post-menarcheal girls (N = 104) only, the second tercile of p,p'-DDE was statistically significantly associated with decreased AMH levels at 12 years old (Tercile 2 v. Tercile 1: -0.61 ng/mL, 95% CI = -1.16, -0.05, Tercile 3 v. Tercile 1: 0.02 ng/mL, 95% CI = -0.51, 0.54). Both mixture models returned null associations. Despite the limited associations observed in this study, we recommend exploring these associations in larger mother-child cohorts and at older ages.

The Effect of Maternal Diet and Lifestyle on the Risk of Childhood Obesity

Background/Objectives: Childhood obesity is a global health problem that affects at least 41 million children under the age of five. Increased BMI in children is associated with serious long-term health consequences, such as type 2 diabetes, cardiovascular disease, and psychological problems, including depression and low self-esteem. Although the etiology of obesity is complex, research suggests that the diet and lifestyle of pregnant women play a key role in shaping metabolic and epigenetic changes that can increase the risk of obesity in their children. Excessive gestational weight gain, unhealthy dietary patterns (including the Western diet), and pregnancy complications (such as gestational diabetes) are some of the modifiable factors that contribute to childhood obesity. The purpose of this narrative review is to summarize the most important and recent information on the impact of the diet and lifestyle of pregnant women on the risk of childhood obesity. Methods: This article is a narrative review that aims to summarize the available literature on the impact of pregnant women's diet and lifestyle on the risk of obesity in their offspring, with a focus on metabolic and epigenetic mechanisms. Results/Conclusions: Current evidence suggests that a pregnant woman's lifestyle and diet can significantly contribute to lowering the risk of obesity in their offspring. However, further high-quality research is needed to understand better the metabolic and epigenetic relationships concerning maternal factors that predispose offspring to obesity.

Prenatal Exposure to Chemical Mixtures and Metabolic Syndrome Risk in Children

Importance

Prenatal exposure to ubiquitous endocrine-disrupting chemicals (EDCs) may increase the risk of metabolic syndrome (MetS) in children, but few studies have studied chemical mixtures or explored underlying protein and metabolic signatures.

Objective

To investigate associations of prenatal exposure to EDC mixtures with MetS risk score in children and identify associated proteins and metabolites.

Design, Setting, and Participants

This population-based, birth cohort study used data collected between April 1, 2003, and February 26, 2016, from the Human Early Life Exposome cohort based in France, Greece, Lithuania, Norway, Spain, and the UK. Eligible participants included mother-child pairs with measured prenatal EDC exposures and complete data on childhood MetS risk factors, proteins, and metabolites. Data were analyzed between October 2022 and July 2023.

Exposures

Nine metals, 3 organochlorine pesticides, 5 polychlorinated biphenyls, 2 polybrominated diphenyl ethers (PBDEs), 5 perfluoroalkyl substances (PFAS), 10 phthalate metabolites, 3 phenols, 4 parabens, and 4 organophosphate pesticide metabolites measured in urine and blood samples collected during pregnancy.

Main Outcomes and Measures

At 6 to 11 years of age, a composite MetS risk score was constructed using z scores of waist circumference, systolic and diastolic blood pressures, triglycerides, high-density lipoprotein cholesterol, and insulin levels. Childhood levels of 44 urinary metabolites, 177 serum metabolites, and 35 plasma proteins were quantified using targeted methods. Associations were assessed using bayesian weighted quantile sum regressions applied to mixtures for each chemical group.

Results

The study included 1134 mothers (mean [SD] age at birth, 30.7 [4.9] years) and their children (mean [SD] age, 7.8 [1.5] years; 617 male children [54.4%] and 517 female children [45.6%]; mean [SD] MetS risk score, -0.1 [2.3]). MetS score increased per 1-quartile increase of the mixture for metals (β = 0.44; 95% credible interval [CrI], 0.30 to 0.59), organochlorine pesticides (β = 0.22; 95% CrI, 0.15 to 0.29), PBDEs (β = 0.17; 95% CrI, 0.06 to 0.27), and PFAS (β = 0.19; 95% CrI, 0.14 to 0.24). High-molecular weight phthalate mixtures (β = -0.07; 95% CrI, -0.10 to -0.04) and low-molecular weight phthalate mixtures (β = -0.13; 95% CrI, -0.18 to -0.08) were associated with a decreased MetS score. Most EDC mixtures were associated with elevated proinflammatory proteins, amino acids, and altered glycerophospholipids, which in turn were associated with increased MetS score.

Conclusions and Relevance

This cohort study suggests that prenatal exposure to EDC mixtures may be associated with adverse metabolic health in children. Given the pervasive nature of EDCs and the increase in MetS, these findings hold substantial public health implications.

Association of maternal exposure to endocrine disruptor chemicals with cardio-metabolic risk factors in children during childhood: a systematic review and meta-analysis of cohort studies

BACKGROUND

In the present systematic review and meta-analysis, the association of maternal exposure to the endocrine disrupting chemicals (EDCs) with cardio-metabolic risk factors in children during childhood for the first time.

METHOD

The PubMed, Scopus, EMBASE, and Web of Science databases were systematically searched, up to Feb 2023. In total 30 cohort studies had our inclusion criteria. A random-effects model was used for the variables that had considerable heterogeneity between studies. The Newcastle-Ottawa Scale (NOS) tool was used to classify the quality score of studies. All statistical analyses were conducted using Stata 14 and P-value < 0.05 considered as a significant level.

RESULTS

In the meta-analysis, maternal exposure to the EDCs was weakly associated with higher SBP (Fisher_Z: 0.06, CI: 0.04, 0.08), BMI (Fisher_Z: 0.07, CI: 0.06, 0.08), and WC (Fisher_Z: 0.06, CI: 0.03, 0.08) z-scores in children. A significant linear association was found between maternal exposure to the bisphenol-A and pesticides with BMI and WC z-score in children (p < 0.001). Subgroup analysis showed significant linear association of BPA and pesticides, in the urine samples of mothers at the first trimester of pregnancy, with BMI and WC z-score in children from 2-8 years (p < 0.05).

CONCLUSION

Prenatal exposure to the EDCs in the uterine period could increase the risk of obesity in children. Maternal exposure to bisphenol-A and pesticides showed the strongest association with the obesity, especially visceral form, in the next generation.

Maternal Seafood Consumption during Pregnancy and Cardiovascular Health of Children at 11 Years of Age

Nutrition is critical during pregnancy for the healthy growth of the developing infant, who is fully dependent on maternal dietary omega-3 supply for development. Fatty fish, a main dietary source of omega-3, is associated with decreased cardiovascular risk in adults. We conducted a longitudinal study based on a mother-offspring cohort as part of the project Infancia y Medio Ambiente (INMA) in order to assess whether fish intake during pregnancy relates to cardiovascular health in children. A total of 657 women were included and followed throughout pregnancy until birth, and their children were enrolled at birth and followed up until age 11-12. A semi-quantitative food frequency questionnaire was used to assess the daily intake of foods during the 1st and 3rd trimesters of pregnancy. Cardiovascular assessments included arterial stiffness (assessed by carotid-femoral pulse wave velocity [PWV]) and retinal microcirculation (photographic assessment of central retinal arteriolar and venular equivalent [CRAE and CRVE]). The association between maternal fish consumption and cardiovascular outcomes of offspring at 11 years of age was evaluated using multivariable linear regression models. There were no statistically significant differences in any cardiovascular endpoint in children whose mothers had a higher fish consumption during pregnancy compared to those with a lower fish consumption. We found a slightly higher PWV (β = 0.1, 95% CI = 0.0; 0.2, p for trend = 0.047) in children whose mothers had a higher consumption of canned tuna during the 1st trimester of pregnancy. Fish intake during pregnancy was found to be unrelated to the offspring's cardiovascular health at 11 years of age. The beneficial cardiovascular effects of fish consumption during pregnancy on the offspring are still inconclusive.

Associations of per- and polyfluoroalkyl substances, polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers with oxidative stress markers: A systematic review and meta-analysis

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) are intentionally produced persistent organic pollutants (POPs) that are resistant to environmental degradation. Previous in-vitro and in-vivo studies have shown that POPs can induce oxidative stress, which is linked to neurodegenerative diseases, cardiovascular diseases, and cancer. However, findings in epidemiological studies are inconsistent and an evidence synthesis study is lacking to summarize the existing literature and explore research gaps.

OBJECTIVE

We evaluated the effects of PFAS, PCBs, OCPs, and PBDEs, on oxidative stress biomarkers in epidemiological studies.

METHODS

A literature search was conducted in PubMed, Embase, and Cochrane CENTRAL to identify all published studies related to POPs and oxidative stress up to December 7th, 2022. We included human observational studies reporting at least one exposure to POPs and an oxidative stress biomarker of interest. Random-effects meta-analyses on standardized regression coefficients and effect direction plots with one-tailed sign tests were used for quantitative synthesis.

RESULTS

We identified 33 studies on OCPs, 35 on PCBs, 49 on PFAS, and 12 on PBDEs. Meta-analyses revealed significant positive associations of α-HCH with protein carbonyls (0.035 [0.017, 0.054]) and of 4'4-DDE with malondialdehyde (0.121 [0.056, 0.187]), as well as a significant negative association between 2'4-DDE and total antioxidant capacity (TAC) (-0.042 [-0.079, -0.004]), all β [95%CI]. Sign tests showed a significant positive association between PCBs and malondialdehyde (pone-tailed = 0.03). Additionally, we found significant negative associations of OCPs with acetylcholine esterase (pone-tailed = 0.02) and paraoxonase-1 (pone-tailed = 0.03). However, there were inconsistent associations of OCPs with superoxide dismutase, glutathione peroxidase, and catalase.

CONCLUSIONS

Higher levels of OCPs were associated with increased levels of oxidative stress through increased pro-oxidant biomarkers involving protein oxidation, DNA damage, and lipid peroxidation, as well as decreased TAC. These findings have the potential to reveal the underlying mechanisms of POPs toxicity.

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.

Dichlorodiphenyltrichloroethane for Malaria and Agricultural Uses and Its Impacts on Human Health

Pesticides are widely used in agriculture and disease control, and dichlorodiphenyltrichloroethane (DDT) is one of the most used pesticides in human history. Besides its significant contributions in pest control in agriculture, DDT was credited as having saved millions of human lives for controlling malaria and other deadly insect-transmitted diseases. Even today, the use of DDT in some countries for malaria control cannot be replaced without endangering people who live there. The recent COVID-19 pandemic has changed our lives and reminded us of the challenges in dealing with infectious diseases, especially deadly ones including malaria. However, DDT and its metabolites are stable, persist long, are found in almost every corner of the world, and their persistent effects on humans, animals, and the environment must be seriously considered. This review will focus on the history of DDT use for agriculture and malaria control, the pathways for the spread of DDT, benefits and risks of DDT use, DDT exposure to animals, humans, and the environment, and the associated human health risks. These knowledge and findings of DDT will benefit the selection and management of pesticides worldwide.

Physical exercise and persistent organic pollutants

Exposure to the legacy and emerging persistent organic pollutants (POPs) incessantly has become an important threat to individual health, which is closely related to neurodevelopment, endocrine and cardiovascular homeostasis. Exercise, on the other hand, has been consistently shown to improve physical fitness. Whereas associations between traditional air pollutants, exercise and lung function have been thoroughly reviewed, reviews on associations between persistent organic pollutants and exercise are scarce. Hence, a literature review focused on exercise, exposure to POPs, and health risk assessment was performed for studies published from 2004 to 2022. The purpose of this review is to provide an overview of exposure pathways and levels of POPs during exercise, as well as the impact of exercise on health concerns attributable to the redistribution, metabolism, and excretion of POPs in vivo. Therein lies a broader array of exercise benefits, including insulin sensitizing, mitochondrial DNA repair, lipid metabolism and intestinal microecological balance. Physical exercise is conducive to reduce POPs body burden and resistant to health hazards of POPs generally. Besides, individual lipid metabolism condition is a critical factor in evaluating potential link in exercise, POPs and health effects.

Prenatal exposure to multiple persistent organic pollutants in association with adiposity markers and blood pressure in preadolescents

BACKGROUND

Several studies have reported that prenatal exposure to some persistent organic pollutants (POPs) is associated with higher adiposity in childhood. Few studies have assessed whether this finding persists into adolescence, and few have considered exposure to POPs as a mixture. This study aims to assess the association between prenatal exposure to multiple POPs and adiposity markers and blood pressure in preadolescents.

METHODS

This study included 1667 mother-child pairs enrolled in the PELAGIE (France) and the INMA (Spain) mother-child cohorts. Three polychlorobiphenyls (PCB 138, 153 and 180, treated as a sum of PCBs) and three organochlorine pesticides (p,p'-Dichlorodiphenyldichloroethylene [p,p'-DDE], β-hexachlorocyclohexane [β-HCH], and hexachlorobenzene [HCB]) were assessed in maternal or cord serum. Body mass index z-score (zBMI), abdominal obesity (waist-to-height ratio > 0.5), percentage of fat mass, and blood pressure (mmHg) were measured at around 12 years of age. Single-exposure associations were studied using linear or logistic regressions, and the POP mixture effect was evaluated using quantile G-computation (qgComp) and Bayesian Kernel Machine Regression (BKMR). All models were adjusted for potential confounders and performed for boys and girls together and separately.

RESULTS

Prenatal exposure to the POP mixture was associated with higher zBMI (beta [95 % CI] of the qgComp = 0.15 [0.07; 0.24]) and percentage of fat mass (0.83 [0.31; 1.35]), with no evidence of sex-specific association. These mixture effects were also statistically significant using BKMR. These associations were driven mainly by exposure to HCB and, to a lesser extent, to β-HCH. In addition, the single-exposure models showed an association between β-HCH and p,p'-DDE and higher systolic blood pressure, especially in girls (p,p'-DDE for girls = 1.00 [0.15; 1.86]). No significant associations were found for PCBs.

CONCLUSION

This study suggests that prenatal exposure to POPs, particularly organochlorine pesticides, remains associated with unfavorable cardiometabolic health up to the age of 12.

Endocrine disrupting compounds in the baby's world - A harmful environment to the health of babies

Globally, there has been a significant increase in awareness of the adverse effects of chemicals with known or suspected endocrine-acting properties on human health. Human exposure to endocrine disrupting compounds (EDCs) mainly occurs by ingestion and to some extent by inhalation and dermal uptake. Although it is difficult to assess the full impact of human exposure to EDCs, it is well known that timing of exposure is of importance and therefore infants are more vulnerable to EDCs and are at greater risk compared to adults. In this regard, infant safety and assessment of associations between prenatal exposure to EDCs and growth during infancy and childhood has been received considerable attention in the last years. Hence, the purpose of this review is to provide a current update on the evidence from biomonitoring studies on the exposure of infants to EDCs and a comprehensive view of the uptake, the mechanisms of action and biotransformation in baby/human body. Analytical methods used and concentration levels of EDCs in different biological matrices (e.g., placenta, cord plasma, amniotic fluid, breast milk, urine, and blood of pregnant women) are also discussed. Finally, key issues and recommendations were provided to avoid hazardous exposure to these chemicals, taking into account family and lifestyle factors related to this exposure.

Skeptical Look at the Clinical Implication of Metabolic Syndrome in Childhood Obesity

Metabolic syndrome (MetS) is defined by a cluster of several cardio-metabolic risk factors, specifically visceral obesity, hypertension, dyslipidemia, and impaired glucose metabolism, which together increase risks of developing future cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D). This article is a narrative review of the literature and a summary of the main observations, conclusions, and perspectives raised in the literature and the study projects of the Working Group of Childhood Obesity (WGChO) of the Italian Society of Paediatric Endocrinology and Diabetology (ISPED) on MetS in childhood obesity. Although there is an agreement on the distinctive features of MetS, no international diagnostic criteria in a pediatric population exist. Moreover, to date, the prevalence of MetS in childhood is not certain and thus the true value of diagnosis of MetS in youth as well as its clinical implications, is unclear. The aim of this narrative review is to summarize the pathogenesis and current role of MetS in children and adolescents with particular reference to applicability in clinical practice in childhood obesity.

Nutritional Modulation of Associations between Prenatal Exposure to Persistent Organic Pollutants and Childhood Obesity: A Prospective Cohort Study

BACKGROUND

Prenatal exposure to persistent organic pollutants (POPs) may contribute to the development of childhood obesity and metabolic disorders. However, little is known about whether the maternal nutritional status during pregnancy can modulate these associations.

OBJECTIVES

The main objective was to characterize the joint associations and interactions between prenatal levels of POPs and nutrients on childhood obesity.

METHODS

We used data from to the Spanish INfancia y Medio Ambiente-Environment and Childhood (INMA) birth cohort, on POPs and nutritional biomarkers measured in maternal blood collected at the first trimester of pregnancy and child anthropometric measurements at 7 years of age. Six organochlorine compounds (OCs) [dichlorodiphenyldichloroethylene, hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH) and polychlorinated biphenyls 138, 153, 180] and four per- and polyfluoroalkyl substances (PFAS) were measured. Nutrients included vitamins (D, B12, and folate), polyunsaturated fatty acids (PUFAs), and dietary carotenoids. Two POPs-nutrients mixtures data sets were established: a) OCs, PFAS, vitamins, and carotenoids (n=660), and b) OCs, PUFAs, and vitamins (n=558). Joint associations of mixtures on obesity were characterized using Bayesian kernel machine regression (BKMR). Relative importance of biomarkers and two-way interactions were identified using gradient boosting machine, hierarchical group lasso regularization, and BKMR. Interactions were further characterized using multivariate regression models in the multiplicative and additive scale.

RESULTS

Forty percent of children had overweight or obesity. We observed a positive overall joint association of both POPs-nutrients mixtures on overweight/obesity risk, with HCB and vitamin B12 the biomarkers contributing the most. Recurrent interactions were found between HCB and vitamin B12 across screening models. Relative risk for a natural log increase of HCB was 1.31 (95% CI: 1.11, 1.54, pInteraction=0.02) in the tertile 2 of vitamin B12 and in the additive scale a relative excess risk due to interaction of 0.11 (95% CI: 0.02, 0.20) was found. Interaction between perfluorooctane sulfonate and β-cryptoxanthin suggested a protective effect of the antioxidant on overweight/obesity risk.

CONCLUSION

These results support that maternal nutritional status may modulate the effect of prenatal exposure to POPs on childhood overweight/obesity. These findings may help to develop a biological hypothesis for future toxicological studies and to better interpret inconsistent findings in epidemiological studies. https://doi.org/10.1289/EHP11258.

Expression levels and network analysis of inflammamiRs in peripheral blood mononuclear cells exposed to DDE "in vitro"

Recent studies have demonstrated that dichlorodiphenyldichloroethylene (DDE) induced a pro-inflammatory condition in peripheral blood mononuclear cells (PBMC). However, the molecular mechanisms implicated in this condition are poorly understood. Therefore, this study aimed to evaluate miR-155, miR-126, and miR-21 expression levels in PBMC exposed "in vitro" to DDE. PBMC were dosed with increasing concentrations of DDE (10-80 µg mL^-1) at different treatment times (0-24 h). The results showed an up-regulation in the expression levels of assessed miRNAs (miR-155, miR-146, and miR-21) after PBMCs were exposed to DDE. Besides, bioinformatic analysis was performed to understand the biological roles of assessed miRNAs. The bioinformatic analysis shows that assessed miRNAs are associated with regulating signaling pathways involved in cancer, apoptosis, cell cycle, inflammation, metabolism, etc. These findings offer new insights into the molecular mechanisms related to the inflammatory processes and their regulation induced by DDE in PBMC exposed "in vitro".

Multi-omics signatures of the human early life exposome

Environmental exposures during early life play a critical role in life-course health, yet the molecular phenotypes underlying environmental effects on health are poorly understood. In the Human Early Life Exposome (HELIX) project, a multi-centre cohort of 1301 mother-child pairs, we associate individual exposomes consisting of >100 chemical, outdoor, social and lifestyle exposures assessed in pregnancy and childhood, with multi-omics profiles (methylome, transcriptome, proteins and metabolites) in childhood. We identify 1170 associations, 249 in pregnancy and 921 in childhood, which reveal potential biological responses and sources of exposure. Pregnancy exposures, including maternal smoking, cadmium and molybdenum, are predominantly associated with child DNA methylation changes. In contrast, childhood exposures are associated with features across all omics layers, most frequently the serum metabolome, revealing signatures for diet, toxic chemical compounds, essential trace elements, and weather conditions, among others. Our comprehensive and unique resource of all associations ( https://helixomics.isglobal.org/ ) will serve to guide future investigation into the biological imprints of the early life exposome.

Prenatal exposure to mixtures of phthalates and phenols and body mass index and blood pressure in Spanish preadolescents

BACKGROUND

Pregnant women are simultaneously exposed to several non-persistent endocrine-disrupting chemicals, which may influence the risk of childhood obesity and cardiovascular diseases later in life. Previous prospective studies have mostly examined single-chemical effects, with inconsistent findings. We assessed the association between prenatal exposure to phthalates and phenols, individually and as a mixture, and body mass index (BMI) and blood pressure (BP) in preadolescents.

METHODS

We used data from the Spanish INMA birth cohort study (n = 1,015), where the 1st and 3rd- trimester maternal urinary concentrations of eight phthalate metabolites and six phenols were quantified. At 11 years of age, we calculated BMI z-scores and measured systolic and diastolic BP. We estimated individual chemical effects with linear mixed models and joint effects of the chemical mixture with hierarchical Bayesian kernel machine regression (BKMR). Analyses were stratified by sex and by puberty status.

RESULTS

In single-exposure models, benzophenone-3 (BP3) was nonmonotonically associated with higher BMI z-score (e.g. Quartile (Q) 3: β = 0.23 [95% CI = 0.03, 0.44] vs Q1) and higher diastolic BP (Q2: β = 1.27 [0.00, 2.53] mmHg vs Q1). Methyl paraben (MEPA) was associated with lower systolic BP (Q4: β = -1.67 [-3.31, -0.04] mmHg vs Q1). No consistent associations were observed for the other compounds. Results from the BKMR confirmed the single-exposure results and showed similar patterns of associations, with BP3 having the highest importance in the mixture models, especially among preadolescents who reached puberty status. No overall mixture effect was found, except for a tendency of higher BMI z-score and lower systolic BP in girls.

CONCLUSIONS

Prenatal exposure to UV-filter BP3 may be associated with higher BMI and diastolic BP during preadolescence, but there is little evidence for an overall phthalate and phenol mixture effect.

Diet quality and exposure to endocrine-disrupting chemicals among US adults

Human exposure to endocrine-disrupting chemicals (EDCs) may increase risk for chronic disease. Diet is a significant source of EDC exposure, yet healthy diets recommended for chronic disease prevention have not been thoroughly examined for associations with EDC exposure. Using data from the National Health and Nutrition Examination Survey 2013-2016, we examined associations of dietary patterns with exposure to non-persistent EDCs potentially consumed through diet. EDCs were measured in spot urine samples. Diet was assessed using 24-h recalls. Multivariable linear regression was used to examine associations of three healthy diet scores [Healthy Eating Index (HEI), relative Mediterranean Diet (rMED), and Dietary Approaches to Stop Hypertension] and fast-food consumption with EDCs. In fully adjusted models, no diet was associated with exposure to the bisphenols, phthalates, or polycyclic aromatic hydrocarbons examined. A 1-point increase in rMED (of 18 possible points) was associated with 2.7% (95% CI: 1.7%, 3.8%) greater urinary nitrate. A 10-point increase in HEI (of 100 possible points) was associated with 5.3% (95% CI: 2.8%, 7.9%) greater nitrate and 6.8% (95% CI: 4.5%, 9.2%) greater perchlorate. Because perchlorate and nitrate can disrupt thyroid hormone production, we conducted an exploratory analysis to examine whether these chemicals mediate an association between diet and thyroid hormones. A 10-point increase in HEI was associated with 0.6% reduced serum total thyroxine (95% CI: 1.7%, 0.5%) among all adults, with 57.5% of the effect explained by perchlorate. Nitrate mediated an association of rMED with modestly reduced total triiodothyronine among females. Most EDCs examined had no association with the diets evaluated, indicating that recommended healthy diets were not protective against EDC exposures. As observed with two thyroid antagonists, some recommended diets may increase EDC exposures and related adverse health outcomes. Additional work should identify effective food production and processing practices to reduce dietary exposures to potentially harmful EDCs.

Prenatal exposure to multiple organochlorine compounds and childhood body mass index

Background

Prenatal exposure to organochlorine compounds (OCs) has been associated with increased childhood body mass index (BMI); however, only a few studies have focused on longitudinal BMI trajectories, and none of them used multiple exposure mixture approaches.

Aim

To determine the association between in-utero exposure to eight OCs and childhood BMI measures (BMI and BMI z-score) at 4 years and their yearly change across 4-12 years of age in 279 Rhea child-mother dyads.

Methods

We applied three approaches: (1) linear mixed-effect regressions (LMR) to associate individual compounds with BMI measures; (2) Bayesian weighted quantile sum regressions (BWQSR) to provide an overall OC mixture association with BMI measures; and (3)Bayesian varying coefficient kernel machine regressions (BVCKMR) to model nonlinear and nonadditive associations.

Results

In the LMR, yearly change of BMI measures was consistently associated with a quartile increase in hexachlorobenzene (HCB) (estimate [95% Confidence or Credible interval] BMI: 0.10 [0.06, 0.14]; BMI z-score: 0.02 [0.01, 0.04]). BWQSR results showed that a quartile increase in mixture concentrations was associated with yearly increase of BMI measures (BMI: 0.10 [0.01, 0.18]; BMI z-score: 0.03 [0.003, 0.06]). In the BVCKMR, a quartile increase in dichlorodiphenyldichloroethylene concentrations was associated with higher BMI measures at 4 years (BMI: 0.33 [0.24, 0.43]; BMI z-score: 0.19 [0.15, 0.24]); whereas a quartile increase in HCB and polychlorinated biphenyls (PCB)-118 levels was positively associated with BMI measures yearly change (BMI: HCB:0.10 [0.07, 0.13], PCB-118:0.08 [0.04, 012]; BMI z-score: HCB:0.03 [0.02, 0.05], PCB-118:0.02 [0.002,04]). BVCKMR suggested that PCBs had nonlinear relationships with BMI measures, and HCB interacted with other compounds.

Conclusions

All analyses consistently demonstrated detrimental associations between prenatal OC exposures and childhood BMI measures.

Prenatal Environmental Exposure to Persistent Organic Pollutants and Indices of Overweight and Cardiovascular Risk in Dutch Adolescents

Persistent organic pollutants (POPs) may have obesogenic effects. Knowledge about the effects of prenatal exposure to POPs on anthropometric measurements and metabolic parameters into adolescence is limited. Therefore, the aim of the current study was to determine whether prenatal environmental exposure to several POPs is associated with indices of overweight and cardiovascular risk in 13–15-year-old children. In this Dutch observational cohort study, 194 mother–infant pairs were included (1998–2002). Maternal pregnancy serum levels of PCBs, OH-PCBs, PBDEs, and other POPs were measured. At follow-up (2014–2016), levels of cholesterol, HDL-C, LDL-C, triglycerides, fasting insulin, fasting glucose, leptin, and adiponectin were measured in their children. The children’s height, weight, waist circumference, hip circumference, and blood pressure were measured. In total, 101 adolescents (14.4 ± 0.8 years; 53.7% of invited) participated of which 55 were boys. Mean BMI was 19.1 ± 3.6 kg/m² and mean BMI z-score 0.13 ± 1.14. Higher prenatal levels of PCBs were associated with lower levels of HDL-C and adiponectin in boys and higher levels of PBDEs with higher triglycerides in girls. We found significant differences by sex in the associations with OH-PCBs, with lower HDL-C and adiponectin, higher LDL-C/HDL-C ratio, fasting glucose, HOMA2-IR, height, and weight for boys. Our study indicates that higher prenatal exposure to PCBs, OH-PCBs, and PBDEs was associated with adolescent levels of some metabolic cardiovascular risk markers and hormones associated with the development of obesity and cardiovascular disease.

Early life PCB138 exposure induces kidney injury secondary to hyperuricemia in male mice

Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants (POPs) that have adverse effects on human health. However, the long-term health effects and potential mechanism of neonatal exposure to PCBs are still unclear. In this study, nursing male mice exposed to PCB138 at 0.5, 5, and 50 μg/kg body weight (bw) from postnatal day (PND) 3 to PND 21 exhibited increased serum uric acid levels and liver uric acid synthase activity at 210 days of age. We also found an increased kidney somatic index in the 50 μg/kg group and kidney fibrosis in the 5 and 50 μg/kg groups. Mechanistically, PCB138 induced mitochondrial dysfunction and endoplasmic reticulum (ER) stress, which might have led to inflammatory responses, such as activation of the NF-κB (nuclear factor kappa-B) and NLRP3 (NOD-like receptor protein 3) pathways. The inflammatory response might regulate renal fibrosis and hypertrophy. In summary, this study reports a long-term effect of neonatal PCB exposure on uric acid metabolism and secondary nephrotoxicity and clarifies the underlying mechanism. Our work also indicates that early life pollutant exposure may be an important cause of diseases later in life.

Obesity II: Establishing causal links between chemical exposures and obesity

Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.

New insights on the effects of endocrine-disrupting chemicals on children

OBJECTIVE

Endocrine disrupting chemicals (EDCs) are present in many areas and materials of the common life, and exposure to these chemicals can occur from products to personal care, from air and food. This review aims to summarize the more recent epidemiological findings for the impact of EDCs on endocrine system health in children, including effects in growth, metabolism, sexual development, and reproduction.

SOURCES

The MEDLINE database (PubMed) was searched on August 24th, 2021, filtering for EDCs, endocrine disruptors, children, and humans.

SUMMARY OF THE FINDINGS

Intrauterine exposure of EDCs can have transgenerational effects, thus laying the foundation for disease in later life. The dose-response relationship may not always be predictable as even low-level exposures that may occur in everyday life can have significant effects on a susceptible individual. Although individual compounds have been studied in detail, the effects of a combination of these chemicals are yet to be studied to understand the real-life situation where human beings are exposed to a "cocktail effect" of these EDCs. Epidemiological studies in humans suggest EDCs' effects on prenatal growth, thyroid function, glucose metabolism, obesity, puberty, and fertility mainly through epigenetic mechanisms.

CONCLUSIONS

EDCs cause adverse effects in animals, and their effects on human health are now known and irrefutable. Because people are typically exposed to multiple endocrine disruptors, assessing public health effects is difficult. Legislation to ban EDCs and protect especially pregnant women and young children is required and needs to be revised and adjusted to new developments on a regular basis.

Exposure to bedroom light pollution and cardiometabolic risk: A cohort study from Chinese young adults

Indoor light environment has altered dramatically and exposure to light at night (LAN) potential leads to the progression of cardiometabolic conditions. However, few studies have investigated the effect of bedroom LAN exposure on cardiometabolic risk. To estimate the associations between multi-period bedroom LAN exposure with cardiometabolic risk among Chinese young adults. We objectively measured multi-period bedroom LAN intensity using portable illuminance meter in an ongoing prospective cohort (n = 484). At one-year follow-up, 230 young adults provided fasting blood samples for quantification of cardiometabolic parameters. Cardiometabolic (CM)-risk score was derived as the sum of standardized sex-specific z-scores for waist circumference (WC), mean arterial pressure (MAP), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG) and homeostasis model assessment for insulin resistance (HOMA-IR), with HDL-C multiplied by - 1. Multivariate and univariable linear regression models were used to examine associations of multi-period bedroom LAN exposure with cardiometabolic risk. Exposure to higher bedroom LAN intensity is associated with 1.47-unit increase in CM-risk score (95% CI: 0.69-2.25; P < 0.001). Besides, post-bedtime light exposure was associated with elevated fasting insulin (PBL-1h: β = 0.06, 95% CI: 0.01-0.10; PBL-4h: β = 0.33, 95% CI: 0.19-0.47) and HOMA-IR (PBL-1h: β = 0.013, 95% CI: 0-0.03; PBL-4h: β = 0.07, 95% CI: 0.04-0.11) while pre-awake light exposure was associated with elevated total cholesterol (PAL-1h: β = 0.03, 95% CI: 0.02-0.04; PAL-2h: β = 0.02, 95% CI: 0.01-0.03), triglyceride (PAL-1h: β = 0.015, 95% CI: 0.01-0.02; PAL-2h: β = 0.01, 95% CI: 0-0.02) and low-density lipoprotein cholesterol (PAL-1h: β = 0.02, 95% CI: 0.01-0.03; PAL-2h: β = 0.02, 95% CI: 0.01-0.03). Among young adults, bedroom LAN exposure was significantly associated with higher cardiometabolic risk. Furthermore, different periods of bedroom light exposure have time-dependent effect on cardiometabolic risk. Further research is needed to confirm our findings and to elucidate potential mechanisms.

Prenatal exposure to persistent organic pollutants and childhood obesity: A systematic review and meta-analysis of human studies

We conducted a systematic review and meta-analysis of the associations between prenatal exposure to persistent organic pollutants (POPs) and childhood obesity. We focused on organochlorines (dichlorodiphenyltrichloroethane [DDT], dichlorodiphenyldichloroethylene [DDE], hexachlorobenzene [HCB], and polychlorinated biphenyls [PCBs]), perfluoroalkyl and polyfluoroalkyl substances (PFAS), and polybrominated diphenyl ethers (PBDEs) that are the POPs more widely studied in environmental birth cohorts so far. We search two databases (PubMed and Embase) through July/09/2021 and identified 33 studies reporting associations with prenatal organochlorine exposure, 21 studies reporting associations with prenatal PFAS, and five studies reporting associations with prenatal PBDEs. We conducted a qualitative review. Additionally, we performed random-effects meta-analyses of POP exposures, with data estimates from at least three prospective studies, and BMI-z. Prenatal DDE and HCB levels were associated with higher BMI z-score in childhood (beta: 0.12, 95% CI: 0.03, 0.21; I2 : 28.1% per study-specific log increase of DDE and beta: 0.31, 95% CI: 0.09, 0.53; I2 : 31.9% per study-specific log increase of HCB). No significant associations between PCB-153, PFOA, PFOS, or pentaPBDEs with childhood BMI were found in meta-analyses. In individual studies, there was inconclusive evidence that POP levels were positively associated with other obesity indicators (e.g., waist circumference).

Relationship between Prenatal or Postnatal Exposure to Pesticides and Obesity: A Systematic Review

In recent years, the worldwide prevalence of overweight and obesity among adults and children has dramatically increased. The conventional model regarding the onset of obesity is based on an imbalance between energy intake and expenditure. However, other possible environmental factors involved, such as the exposure to chemicals like pesticides, cannot be discarded. These compounds could act as endocrine-disrupting chemicals (EDC) that may interfere with hormone activity related to several mechanisms involved in body weight control. The main objective of this study was to systematically review the data provided in the scientific literature for a possible association between prenatal and postnatal exposure to pesticides and obesity in offspring. A total of 25 human and 9 animal studies were analyzed. The prenatal, perinatal, and postnatal exposure to organophosphate, organochlorine, pyrethroid, neonicotinoid, and carbamate, as well as a combined pesticide exposure was reviewed. This systematic review reveals that the effects of pesticide exposure on body weight are mostly inconclusive, finding conflicting results in both humans and experimental animals. The outcomes reviewed are dependent on many factors, including dosage and route of administration, species, sex, and treatment duration. More research is needed to effectively evaluate the impact of the combined effects of different pesticides on human health.