Prenatal phthalate exposure and language development in toddlers from the Odense Child Cohort

Association between mixed exposure of phenols, parabens, phthalates and cognitive function in US elders

BACKGROUND

In an aging society, understanding the factors influencing cognitive function in older adults is of great significance. Phenols, parabens, and phthalates (PAEs) can disrupt normal neural signaling. This research aims to investigate the association between mixed exposure of phenols, parabens, PAEs and cognitive function in US elders. Given that older adults are a vulnerable group in terms of health, and cognitive decline can severely impact their quality of life and independence. Studying the effects of these commonly - encountered environmental chemicals on their cognitive function is crucial as it can provide scientific basis for formulating public health policies.

METHODS

A total of 856 participants were selected from National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014. The generalized linear (GLM), weighted quantile sum (WQS), and Bayesian kernel machine regression (BKMR) models were used to evaluate the associations between mixed PAEs and the standardized z-scores for the four cognitive tests.

RESULTS

The mixed effect of the nine exposures examined is positively associated with lower IRT scores (OR: 1.77, 95 % CI: 1.04-3.02) for males in the WQS regression model. MEHP exhibits the largest contribution of all combinations. In the BKMR regression model, mixed exposure and cognitive impairment show positive correlation in the IRT, the DSST, and the global test for males.

CONCLUSION

Exposure to phenols, parabens, and PAEs may negatively affect cognition in older adults, particularly the male population. The effect of mixed exposure is positively associated with lower IRT scores and MECP has a dominant role.

Prenatal and Childhood Phthalate Mixtures and Adolescent Sleep Health in the HOME Study

BACKGROUND

The biological mechanisms linking early life phthalate exposure with adverse behaviors and cardiometabolic conditions also impact sleep health, but whether early life exposure impacts adolescent sleep is unknown.

OBJECTIVES

We evaluated whether gestational and childhood urinary phthalate metabolite mixtures were associated with sleep characteristics during adolescence. We also examined periods of heightened susceptibility to individual phthalates.

METHODS

In the Health Outcomes and Measures of the Environment (HOME) Study (Cincinnati, Ohio; 2003-2006; n = 156 ), we quantified urinary metabolites of eight parent phthalate diesters during pregnancy (16- and 26-wk) and childhood (ages 1, 2, 3, 4, 5, 8, and 12 years). Using regression calibration approaches, we estimated average measurement error-corrected phthalate metabolite concentrations during pregnancy and childhood. We used wrist actigraphy to assess sleep characteristics for 1 wk among participants at age 12. Using quantile-based g-computation, we estimated covariate-adjusted differences in sleep efficiency (%), sleep fragmentation index scores (%), sleep duration (minutes) per quartile increase in all phthalate metabolite concentrations (ψ ), and weights indicating the contribution of each metabolite to ψ . Using multiple informant models, we examined whether associations between individual phthalate metabolites and sleep characteristics varied by timing of exposure.

RESULTS

Increasing all gestational phthalate metabolites by a quartile was associated with lower sleep efficiency [ψ = - 1.3 % ; 95% confidence interval (CI): - 2.4 , - 0.3 ] and higher sleep fragmentation (ψ = 1.6 % ; 95% CI: 0.3, 3.0); mono-n-butyl phthalate (MnBP) and di(2-ethylhexyl) phthalate (DEHP) metabolites contributed most to these relations. Higher childhood phthalate metabolite mixture quartiles were associated with shorter sleep duration (ψ = - 21 minutes; 95% CI: - 34 , - 9 ); monoethyl phthalate (MEP) and monocarboxyoctyl phthalate (MCOP) contributed most to this association. We found that higher DEHP metabolite concentrations during pregnancy were more strongly related to higher sleep fragmentation than childhood concentrations. In contrast, higher MEP and MnBP concentrations during childhood, but not pregnancy, were consistently associated with shorter sleep duration.

DISCUSSION

Phthalate metabolite concentrations during pregnancy and childhood were associated with poorer adolescent sleep health. https://doi.org/10.1289/EHP15221.

Using machine learning to investigate the influence of the prenatal chemical exposome on neurodevelopment of young children

Research investigating the prenatal chemical exposome and child neurodevelopment has typically focused on a limited number of chemical exposures and controlled for sociodemographic factors and maternal mental health. Emerging machine learning approaches may facilitate more comprehensive examinations of the contributions of chemical exposures, sociodemographic factors, and maternal mental health to child neurodevelopment. A machine learning pipeline that utilized feature selection and ranking was applied to investigate which common prenatal chemical exposures and sociodemographic factors best predict neurodevelopmental outcomes in young children. Data from 406 maternal-child pairs enrolled in the APrON study were used. Maternal concentrations of 32 environmental chemical exposures (i.e., phthalates, bisphenols, per- and polyfluoroalkyl substances (PFAS), metals, trace elements) measured during pregnancy and 11 sociodemographic factors, as well as measures of maternal mental health and urinary creatinine were entered into the machine learning pipeline. The pipeline, which consisted of a RReliefF variable selection algorithm and support vector machine regression model, was used to identify and rank the best subset of variables predictive of cognitive, language, and motor development outcomes on the Bayley Scales of Infant Development-Third Edition (Bayley-III) at 2 years of age. Bayley-III cognitive scores were best predicted using 29 variables, resulting in a correlation coefficient of r = 0.27 (R2=0.07). For language outcomes, 45 variables led to the best result (r = 0.30; R2=0.09), whereas for motor outcomes 33 variables led to the best result (r = 0.28, R2=0.09). Environmental chemicals, sociodemographic factors, and maternal mental health were found to be highly ranked predictors of cognitive, language, and motor development in young children. Our findings demonstrate the potential of machine learning approaches to identify and determine the relative importance of different predictors of child neurodevelopmental outcomes. Future developmental neurotoxicology research should consider the prenatal chemical exposome as well as sample characteristics such as sociodemographic factors and maternal mental health as important predictors of child neurodevelopment.

A critical review of recent advancements in the photocatalysis process, mechanism, and degradation pathways for the removal of phthalates from the contaminated water matrix

Phthalates, a sort of plasticizer, are widely utilized in various consumer products and pose significant environmental and health risks due to their persistence and potential toxicity. This review explores the occurrence, sources, environmental impact, and remediation strategies for phthalates. Various remediation techniques have been investigated to address phthalate contamination. Among these, photocatalysis, an advanced oxidation process (AOP), has emerged as a viable approach due to its ability to mineralize organic contaminants into innocuous byproducts. The review discusses the recent advancements in photocatalytic processes, the underlying mechanisms, and degradation pathways for phthalate removal. The mechanism of photocatalytic degradation includes the generation of reactive oxygen species like hydroxyl radicals (OH•) and superoxide radicals (O2-•) and their role in breaking down phthalate molecules. It also highlights recent advancements in photocatalytic materials, such as metal-doped semiconductors and composite materials, which enhance the removal efficiency. The review concludes by emphasizing the need for integrated approaches to achieve effective and sustainable phthalate remediation. Future research should focus on developing efficient and cost-effective photocatalytic materials, optimizing reactor design, and scaling up photocatalytic processes for practical applications. The review also highlights the challenges and limitations of photocatalytic processes, including low quantum efficiency, catalyst deactivation, and mass transfer limitations. Potential areas of study are put forward to address these challenges and further advance the application of photocatalysis for phthalate removal. This review intends to help the development of efficient photocatalytic technologies for the remediation of phthalate-contaminated water by providing a complete overview of the present state of the art.

Measurement of emerging neurocognitive and language skills in the HEALthy Brain and Child Development (HBCD) study

The HEALthy Brain and Child Development (HBCD) study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. The study plans enrolling over 7000 families across 27 sites. This manuscript presents the measures from the Neurocognition and Language Workgroup. Constructs were selected for their importance in normative development, evidence for altered trajectories associated with environmental influences, and predictive validity for child outcomes. Evaluation of measures considered psychometric properties, brevity, and developmental and cultural appropriateness. Both performance measures and caregiver report were used wherever possible. A balance of norm-referenced global measures of development (e.g., Bayley Scales of Infant Development-4) and more specific laboratory measures (e.g., deferred imitation) are included in the HBCD study battery. Domains of assessment include sensory processing, visual-spatial reasoning, expressive and receptive language, executive function, memory, numeracy, adaptive behavior, and neuromotor. Strategies for staff training and quality control procedures, as well as anticipated measures to be added as the cohort ages, are reviewed. The HBCD study presents a unique opportunity to examine early brain and neurodevelopment in young children through a lens that accounts for prenatal exposures, health and socio-economic disparities.

Association of exposure to phthalates and phthalate alternatives with dyslexia in Chinese primary school children

Previous studies have shown associations between children's exposure to phthalates and neurodevelopmental disorders. Whereas the impact of exposure to phthalate alternatives is understudied. This study aimed to evaluate the association of exposure to phthalates/their alternatives with the risk of dyslexia. We recruited 745 children (355 dyslexia and 390 non-dyslexia) via the Tongji Reading Environment and Dyslexia Research Project, and their urine samples were collected. A total of 26 metabolites of phthalates/their alternatives were measured. Multivariate logistic regression and quantile-based g-computation were used to estimate the associations of exposure to the phthalates/their alternatives with dyslexia. More than 80% of the children had 17 related metabolites detected in their urine samples. After adjustment, the association between mono-2-(propyl-6-hydroxy-heptyl) phthalate (OH-MPHP) with the risk of dyslexia was observed. Compared with the lowest quartile of OH-MPHP levels, the odds of dyslexia for the third quartile was 1.93 (95% CI 1.06, 3.57). Regarding mixture analyses, it was found that OH-MPHP contributed the most to the association. Further analyses stratified by sex revealed that this association was only observed in boys. Our results suggested a significantly adverse association of di-2-propylheptyl phthalate exposure with children's language abilities. It highlights the necessity to prioritize the protection of children's neurodevelopment by minimizing their exposure to endocrine-disrupting chemicals like di-2-propylheptyl phthalate.

Exposure to environmentally relevant phthalate mixture during pregnancy alters the physical and hemato-biochemical parameters in Black Bengal goats

Several environmental pollutants, mostly chemicals and plasticizers, have an effect on the reproduction of small ruminants, causing abortion, delayed estrus, and decreased fertility. Phthalates are common in our environment and have been identified as endocrine disrupting chemicals (EDCs). The research work investigated the impact of dietary exposure to a phthalate mixture on physical and hemato-biochemical parameters in pregnant Black Bengal (BB) goats. A total of 20 clinically healthy, 1-2 months pregnant, aged 6-8 months with a body weight of 10-12 kg BB goats were collected and divided into two (n = 10) groups. The treatment group received a standard goat ration with a combination of different phthalates mixture while the control group was provided the same ration with the vehicle of aphthalatemixture until parturition. The physical parameters were measured with appropriate tools and blood samples were collected for hemato-biochemical tests. The results showed that the physiological parameters (body condition score, respiration rate and heart rate) were significantly (P < 0.05) reduced in phthalate-exposed goats without altering rectal temperature and rumen motility. The hematological parameters: RBC count, WBC count, hemoglobin concentration, hematocrit values and RBC indices were significantly (P < 0.05) lower in phthalate-exposed goats. Phthalate-exposed BB goats had significantly (P < 0.05) higher neutrophil and lower lymphocyte counts. Serum glucose, total protein, albumin and total cholesterol levels were significantly (P < 0.05) lower in phthalate-exposed BB goats but higher the values of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and blood urea nitrogen (BUN) levels in treated BB goats. It may be concluded that exposure to a phthalate mixture during pregnancy alters the physical, hematological and biochemical parameters in BB goats.

What risk factors for Developmental Language Disorder can tell us about the neurobiological mechanisms of language development

Language is a complex multidimensional cognitive system that is connected to many neurocognitive capacities. The development of language is therefore strongly intertwined with the development of these capacities and their neurobiological substrates. Consequently, language problems, for example those of children with Developmental Language Disorder (DLD), are explained by a variety of etiological pathways and each of these pathways will be associated with specific risk factors. In this review, we attempt to link previously described factors that may interfere with language development to putative underlying neurobiological mechanisms of language development, hoping to uncover openings for future therapeutical approaches or interventions that can help children to optimally develop their language skills.

Sex-specific associations between maternal phthalate exposure and neurodevelopmental outcomes in children at 2 years of age in the APrON cohort

BACKGROUND

There is inconsistent evidence regarding the sex-specific associations between prenatal phthalate exposure and children's neurodevelopment. This could be due to differences in the phthalate exposures investigated and the neurodevelopmental domains assessed.

OBJECTIVE

To evaluate the associations between prenatal phthalate exposure and sex-specific outcomes on measures of cognition, language, motor, executive function, and behaviour in children 2 years of age in the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort.

METHODS

We evaluated the associations between prenatal phthalate exposure and sex-specific neurodevelopmental outcomes in children at 2 years of age using data from 448 mothers and their children (222 girls, 226 boys). Nine phthalate metabolites were measured in maternal urine collected in the second trimester of pregnancy. Children's cognitive, language, and motor outcomes were assessed using the Bayley Scales of Infant Development - Third Edition (Bayley-III). Parents completed questionnaires on children's executive function and behavior, the Behavior Rating Inventory of Executive Function- Preschool Version (BRIEF-P) and Child Behavior Checklist (CBCL), respectively. Sex-stratified robust multivariate regressions were performed.

RESULTS

Higher maternal concentrations of ΣDEHP and its metabolites were associated with lower scores on the Bayley-III Cognitive (β's from -11.8 to -0.07 95% CI's from -21.3 to -0.01), Language (β's from -11.7 to -0. 09, 95% CI's from -22.3 to -0.02) and Motor (β's from -10.9 to -0.07, 95% CI from -20.4 to -0.01) composites in boys. The patterns of association in girls were in the opposite direction on the Cognitive and Language composites; on the Motor composite they were in the same direction as boys, but of reduced strength. Higher concentrations of ΣDEHP and its metabolites were associated with higher scores (i.e., more difficulties) on all measures of executive function in girls: inhibitory self-control (B's from 0.05 to 0.11, 95% CI s from -0.01 to 0.15), flexibility (B's from 0.04 to 0.11, 95% CI s from 0.01 to 0.21) and emergent metacognition (B's from -0.01 to 0.06, 95% CIs from -0.01 to 0.20). Similar patterns of attenuated associations were seen in boys. Higher concentrations of ΣDEHP and its metabolites were associated with more Externalizing Problems in girls and boys (B's from 0.03 to 6.82, 95% CIs from -0.08 to 12.0). Two phthalates, MMP and MBP, had sex-specific adverse associations on measures of executive function and behaviour, respectively, while MEP was positively associated with boys' cognitive, language, and motor performance. Limited associations were observed between mixtures of maternal phthalates and sex-specific neurodevelopmental outcomes.

CONCLUSIONS

Maternal prenatal concentrations of DEHP phthalates were associated with sex specific difference on measures of cognition and language at 2 years of age, specifically, poorer outcomes in boys. Higher exposure to DEHP was associated with poorer motor, executive function, and behavioural outcomes in girls and boys but the strength of these associations differed by sex. Limited associations were noted between phthalate mixtures and child neurodevelopment.

The association of prenatal phthalates, organophosphorous pesticides, and organophosphate esters with early child language ability in Norway

BACKGROUND

Prenatal exposure to phthalates, organophosphate esters, and organophosphorous pesticides have been associated with neurodevelopmental deficits including language ability, however, few studies consider the effect of exposure mixtures and the potential longitudinal detriments over time.

OBJECTIVE

This study examines the influence of prenatal exposure to phthalates, organophosphate esters, and organophosphorous pesticides, on children's language ability from toddlerhood to the preschool period.

METHODS

This study includes 299 mother-child dyads from Norway in the Norwegian Mother, Father and Child Cohort Study (MoBa). Prenatal exposure to chemicals were assessed at 17 weeks' gestation, and child language skills were assessed at 18 months using the Ages and Stages Questionnaire communication subscale and at preschool age using the Child Development Inventory. We ran two structural equation models to examine the simultaneous influences of chemical exposures on parent-reported and teacher-reported child language ability.

RESULTS

Prenatal organophosphorous pesticides were negatively associated with preschool language ability through language ability at 18 months. Additionally, there was a negative association between low molecular weight phthalates and teacher-reported preschool language ability. There was no effect of prenatal organophosphate esters on child language ability at either 18 months or preschool age.

CONCLUSIONS

This study adds to the literature on prenatal exposure to chemicals and neurodevelopment and highlights the importance of developmental pathways in early childhood.

Iodine Deficiency, Maternal Hypothyroxinemia and Endocrine Disrupters Affecting Fetal Brain Development: A Scoping Review

This scoping review critically discusses the publications of the last 30 years on the impact of mild to moderate iodine deficiency and the additional impact of endocrine disrupters during pregnancy on embryonal/fetal brain development. An asymptomatic mild to moderate iodine deficiency and/or isolated maternal hypothyroxinemia might affect the development of the embryonal/fetal brain. There is sufficient evidence underlining the importance of an adequate iodine supply for all women of childbearing age in order to prevent negative mental and social consequences for their children. An additional threat to the thyroid hormone system is the ubiquitous exposure to endocrine disrupters, which might exacerbate the effects of iodine deficiency in pregnant women on the neurocognitive development of their offspring. Ensuring adequate iodine intake is therefore essential not only for healthy fetal and neonatal development in general, but it might also extenuate the effects of endocrine disruptors. Individual iodine supplementation of women of childbearing age living in areas with mild to moderate iodine deficiency is mandatory as long as worldwide universal salt iodization does not guarantee an adequate iodine supply. There is an urgent need for detailed strategies to identify and reduce exposure to endocrine disrupters according to the "precautional principle".

Prenatal and current phthalate exposure and cognitive development in 7-year-old children from the Odense child cohort

BACKGROUND

Phthalates are endocrine disrupters used in a variety of consumer products. Human studies suggest an association between phthalate exposure and cognitive development but adverse effects of the recently introduced phthalate substitutes have only been sparsely studied.

OBJECTIVES

To investigate associations between prenatal and concurrent exposure to phthalates and IQ in 7-year-old children from the Odense Child Cohort.

METHODS

Pregnant women from the Odense Child Cohort had phthalate metabolites measured in urine samples during 3rd trimester in 2010 to 2012. In addition, phthalates were also measured in urine samples from their offspring at age 7 years. IQ was assessed at age 7 years using four subtests from Wechsler Intelligence Scale for Children. The total study population consisted of 585 mother-child pairs with available prenatal urinary phthalate metabolites concentrations and IQ data at age 7 years. A subset of those (N = 274) had urinary phthalate metabolites measured in child urine at age 7 years. Phthalate concentrations were grouped into tertiles and associations with IQ were investigated using multiple linear regression adjusting for sex, maternal education and maternal/child BMI.

RESULTS

Urinary phthalate metabolite concentrations both in pregnant women and children were generally lower compared to previous cohorts. Children with high prenatal urinary concentrations of MEP and metabolites of DEHP (∑DEHP_m)(3rd tertile) had -3.1 (95% CI: -5.5, -0.6) (MEP) and - 3.0 (-5.5, -0.6) (∑DEHP_m) IQ points at age 7 years compared to children with low concentrations (1st tertile). High concurrent urinary phthalate concentrations of MCPP, ∑DnHxP_m, ∑DiDP_m and ∑DiNP_m in the 3rd tertile was associated with -3.7 (-7.2, -0.2), -4.4 (-7.9, -0.9), -3.7 (-7.2, -0.2) and - 5.6 (-9.1, -2.2) IQ points, respectively, compared to those with the lowest concentrations (1st tertile).

CONCLUSION

We found significant inverse associations between some prenatal and concurrent urinary phthalate concentrations and IQ at age 7 years in this low exposed population. This suggests that exposure to phthalates both prenatally and during early childhood could be hazardous to child neurodevelopment, however, large-scale prospective studies assessing phthalate exposure through multiple urine samples, and possibly investigating cocktail effects of the chemicals as well as long term follow-up are warranted.

Urinary phthalate metabolites and anemia: Findings from the Korean National Environmental Health Survey (2015-2017)

BACKGROUND

Several animal studies have suggested an association between phthalate exposure and decreased hemoglobin levels. To address the lack of epidemiological evidence, we evaluated the association between urinary phthalate metabolite concentrations and hematologic indices by using nationally representative data from Korea.

METHODS

Data from 3722 adults included in the third stage (2015-2017) of the Korean National Environmental Health Survey (KONEHS) were used. The association between various urinary phthalate metabolites and hematologic indices (hemoglobin, hematocrit, mean corpuscular volume [MCV], and red blood cell [RBC], white blood cell [WBC], and platelet counts) was evaluated using linear regression analysis adjusted for potential confounders. Sex-stratified analysis was performed.

RESULTS

All urinary phthalate metabolites were negatively associated with hemoglobin levels. A two-fold increase in urinary mono-(2-ethyl-5-carboxy-pentyl) phthalate (MECPP), mono-carboxyoctyl phthalate (MCOP), mono-carboxyonyl phthalate (MCNP), and mono-(3-carboxypropyl) phthalate (MCPP) levels was associated with a -0.099 g/dL (95% confidence interval (CI), -0.137 to -0.060), -0.116 g/dL (95% CI, -0.156 to -0.076), -0.111 g/dL (95% CI, -0.154 to -0.068), and -0.144 g/dL (95% CI, -0.198 to -0.089) change in hemoglobin levels, respectively. The RBC count and MCV showed negative and positive associations, respectively, with urinary phthalate metabolite concentrations. WBC counts were positively associated with MECPP, MCOP, MCNP, and MCPP levels, whereas the platelet count showed no association with urinary phthalate metabolites.

CONCLUSIONS

Urinary phthalate metabolite concentration showed a negative association with hemoglobin level. Since this was a cross-sectional study, further longitudinal and experimental studies are needed to identify a clear causal linkage and the pathological mechanism underlying phthalate exposure and anemia.

Phthalate Exposure, PPARα Variants, and Neurocognitive Development of Children at Two Years

Background: The PPARα gene may be crucial to the neurotoxic effect of phthalates. However, epidemiological studies considering the neurodevelopmental influence of phthalates interacting with genetic susceptibility are limited. We hypothesized phthalates could interact with the PPARα gene, synergistically affecting neurocognitive development.

Methods: A total of 961 mother-infant pairs were involved in this study. The concentrations of phthalate metabolites in maternal urine during pregnancy were detected. Children’s neurocognitive development was estimated with the Bailey Infant Development Inventory (BSID). Genetic variations in PPARα were genotyped with the Illumina Asian Screening Array. We applied generalized linear regression models to estimate genotypes and phthalate metabolites’ association with children’s neurocognitive development.

Results: After adjusting for potential confounders, the mono-n-butyl phthalate (MnBP) concentration was negatively associated with Psychomotor Development Index (PDI) (β = −0.86, 95% CI: −1.67, −0.04). The associations between MnBP and neurocognitive development might be modified by PPARα rs1800246. Compared with low-MnBP individuals carrying rs1800246 GG genotypes, high-MnBP individuals with the AG + AA genotype had a higher risk of neurocognitive developmental delay, with the odds ratio of 2.76 (95% CI:1.14, 6.24).

Conclusions: Our current study revealed that prenatal exposure to MnBP was negatively correlated with children’s neurocognitive development, and PPARα rs1800246 might modify the association.

Exposure to 15 phthalates and two substitutes (DEHTP and DINCH) assessed in trios of infants and their parents as well as longitudinally in infants exclusively breastfed and after the introduction of a mixed diet

OBJECTIVE

Several phthalates have been restricted/banned due to their adverse endocrine disrupting properties. The use of other phthalates and substitutes has increased. Here we examine the current exposure to phthalates in family trios comprised of infants and their parents and in infants exclusive breastfed and following introduction to a mixed diet.

METHODS

Metabolites of 15 phthalates and two substitutes, di(2-ethylhexyl)-teraphthalate (DEHTP) and diisononyl-cyclohexane-1,2-dicarboxylate (DINCH), were measured in urine samples collected from >100 infants and their parents and in paired urine samples collected from 67 infants, while they were exclusively breastfed and when they got mixed diet.

RESULTS

Among infants and their parents, metabolites of nine out of 15 phthalates and both substitutes were detected in >74% of all samples. Estimated daily intake (DI) calculated as µg/kg/day, showed similar exposure levels among infants and their parents for several of the substances, and infants were more exposed to DEHTP than their mothers. Significantly higher estimated DIs were observed for some low-molecular phthalates in infants exclusively breastfed. In contrast, comparable estimated DIs were observed for many other phthalates and DEHTP regardless of feeding status. For most of the substances, the within-family variation, was lower than the between-family variation. Likewise, the within-infant variation on exclusively breast vs. mixed diet was lower than the between-infant variation. Independent of food status, some infants were concurrently exposed to almost all the measured phthalates and substitutes in higher amounts than others.

CONCLUSION

Surprisingly, irrespective of diet status infants were exposed to several phthalates and substitutes some of which have been regulated for years. Exposure patterns and levels were similar in infants and their parents. Importantly, risk assessment based on new refined reference doses (RfD-AA) exceeded the safety level for anti-androgenic effects in a number of infants and parents, which is of concern.

Associations of prenatal phthalate exposure with neurobehavioral outcomes in 4.5- and 7.5-month-old infants

Phthalates are ubiquitous endocrine-disrupting chemicals, and research indicates that prenatal exposure to some phthalates may affect neurodevelopment. In a prospective birth cohort study, five first-morning urine samples collected across pregnancy were pooled and the following phthalate biomarkers assessed: sum of di-(2-ethylhexyl) phthalate metabolites (ΣDEHP), sum of diisononyl phthalate metabolites (ΣDINP), sum of dibutyl phthalate metabolites (ΣDBP), sum of anti-androgenic metabolites (ΣAA), monoethyl phthalate (MEP), and sum of all phthalate metabolites (ΣAll). The Ages & Stages Questionnaires® (ASQ), a standardized parent-reported, age-adapted screening tool, measured communication, personal-social, problem solving, and motor domains in infants at 4.5 and 7.5 months (n = 123). Adjusting for maternal age, annual household income, gestational age at birth, infant age at assessment, and sex, repeated-measures generalized linear regression models were used to examine associations between prenatal phthalate urine biomarker concentrations and domain scores (assuming a Poisson distribution). Beta estimates were exponentiated back to the domain scale for ease of interpretation. Mothers were mostly white and college-educated, and most reported an annual household income of ≥$60,000. Associations of phthalate concentrations with ASQ outcomes are presented as follows: (1) anti-androgenic phthalate metabolites (ΣDEHP, ΣDINP, ΣDBP, and ΣAA), (2) MEP, which is not anti-androgenic, and (3) ΣAll. Overall, anti-androgenic phthalates were associated with higher (i.e., better) scores. However, there were exceptions, including the finding that a one-unit increase in ΣDBP was associated with a 12% increase in problem solving scores in 4.5-month-old females (β = 1.12; 95% CI: 0.99, 1.28; p = 0.067) but a 85% decrease for 7.5-month-old females (β = 0.54; 95% CI: 0.3, 0.99; p = 0.047). In contrast, MEP was associated with poorer scores on several outcomes. Sex- and timepoint-specific estimates demonstrated a one-unit increase in MEP was associated with: a 52% decrease in personal-social scores in 7.5-month-old males (β = 0.66; 95% CI: 0.46, 0.95; p = 0.02), a 39% decrease in fine motor scores in 7.5-month-old males (β = 0.72; 95% CI: 0.52, 0.98; p = 0.035), and a 6% decrease in fine motor scores in 4.5-month-old females (β = 0.94; 95% CI: 0.88, 0.99; p = 0.03). A one-unit increase in ΣAll was associated with a 4% increase in personal-social scores in 4.5-month-old males (β = 1.04; 95% CI: 0.99, 1.1; p = 0.08) but a 17% decrease in 7.5-month-old males (β = 0.85; 95% CI: 0.73, 0.99; p = 0.03). These data suggest age- and sex-specific associations of prenatal phthalates with infant neurobehavior. The current findings should be confirmed by longitudinal studies with larger sample sizes.

Review of the Existing Evidence for Sex-Specific Relationships between Prenatal Phthalate Exposure and Children's Neurodevelopment

Phthalates are well-known, ubiquitous environmental contaminants influencing children's health and their neurodevelopment. However, results of the previously conducted studies are not entirely conclusive. The aim of this review is to present the current state of knowledge with respect to the association between the prenatal phthalate exposure and sex-specific child neurodevelopmental outcomes. A systematic search of the literature was carried out to identify the studies that analyse the sex-specific association between prenatal exposure to phthalates and cognitive, psychomotor outcomes and behavioural and emotional problems. The search was conducted in May 2021, and it was limited to the papers published in English between January 2015 and April 2021. The following databases were used: PubMed, Scopus and Elsevier. The selection process was carried out by two independent authors according to the inclusion criteria. Of a total of 7542 records, 17 epidemiological studies met the inclusion criteria with regards to phthalate exposure and sex-specific differences in child neurobehavioural development. The review shows no clear pattern of association between maternal exposure to phthalates during pregnancy and offspring neurodevelopment. No clearly pronounced sex specific effects, except for BBzP exposure and decreased motor ablates among girls, have been indicated. Inconsistences in the results, as well as unsolved issues related to the interpretation of the results in the context of the exposure level, outcomes, confounders, and biological plausibility highlight the necessity for further research in the field.

Prenatal exposure to phthalates and its effects upon cognitive and motor functions: A systematic review

Phthalates are chemicals widely used in packaging and consumer products, which have been shown to interfere with normal hormonal function and development in some human and animal studies. In recent decades, pregnant women's exposure to phthalates has been shown to alter the cognitive outcomes of their babies, and some studies have found delays in motor development.

METHODS

electronic databases including PubMed/MEDLINE and Scopus were searched from their inception to March 2021, using the keywords "phthalate", "cognitive" and "motor".

RESULTS

most studies find statistically significant inverse relationships between maternal urinary phthalate concentration during pregnancy and subsequent outcomes in children's cognitive and motor scales, especially in boys rather than girls. However, many associations are not significant, and there were even positive associations, especially in the third trimester.

CONCLUSION

the relationship between exposure to phthalates during pregnancy and low results on neurocognitive scales is sufficiently clear to adopt policies to reduce exposure. Further studies are needed to analyze sex differences, coordination and motor scales, and phthalate levels during breastfeeding.

Early life multiple exposures and child cognitive function: A multi-centric birth cohort study in six European countries

Epidemiological studies mostly focus on single environmental exposures. This study aims to systematically assess associations between a wide range of prenatal and childhood environmental exposures and cognition. The study sample included data of 1298 mother-child pairs, children were 6-11 years-old, from six European birth cohorts. We measured 87 exposures during pregnancy and 122 cross-sectionally during childhood, including air pollution, built environment, meteorology, natural spaces, traffic, noise, chemicals and life styles. The measured cognitive domains were fluid intelligence (Raven's Coloured Progressive Matrices test, CPM), attention (Attention Network Test, ANT) and working memory (N-Back task). We used two statistical approaches to assess associations between exposure and child cognition: the exposome-wide association study (ExWAS) considering each exposure independently, and the deletion-substitution-addition algorithm (DSA) considering all exposures simultaneously to build a final multiexposure model. Based on this multiexposure model that included the exposure variables selected by ExWAS and DSA models, child organic food intake was associated with higher fluid intelligence (CPM) scores (beta = 1.18; 95% CI = 0.50, 1.87) and higher working memory (N-Back) scores (0.23; 0.05, 0.41), and child fast food intake (-1.25; -2.10, -0.40), house crowding (-0.39; -0.62, -0.16), and child environmental tobacco smoke (ETS) (-0.89; -1.42, -0.35), were all associated with lower CPM scores. Indoor PM2.5 exposure was associated with lower N-Back scores (-0.09; -0.16, -0.02). Additional associations in the unexpected direction were found: Higher prenatal mercury levels, maternal alcohol consumption and child higher perfluorooctane sulfonic acid (PFOS) levels were associated with better cognitive performance; and higher green exposure during pregnancy with lower cognitive performance. This first comprehensive and systematic study of many prenatal and childhood environmental risk factors suggests that unfavourable child nutrition, family crowdedness and child indoor air pollution and ETS exposures adversely and cross-sectionally associate with cognitive function. Unexpected associations were also observed and maybe due to confounding and reverse causality.

Prenatal exposure to phthalate esters and its impact on child development

Endocrine disruptive chemicals (EDCs) cause adverse health effects through interaction with endocrine systems. They are classified by chemical structure, effects on specific endocrine systems, their bioaccumulation and/or persistence in the environment, and/or clinically observable effects. In industrial nations, people are exposed to complex mixtures of many different substances all of which may have multiple and deleterious effects upon the individual. The clinical importance of epigenetic changes caused by the action of EDCs during vulnerable phases of development is currently unclear but of particular relevance. Epidemiological studies are criticized because reproducibility is not always guaranteed. Nevertheless, they remain the method of choice for the development and analysis of suitable model systems. Positive associations, despite of sometimes conflicting results, are the key in the selection of factors that can then be analyzed in model systems in an unbiased way. This article reports EDC-caused effects in the fields of growth and metabolism, neurocognitive development and sexual development and reproduction focusing mainly on phthalates and their metabolites. However, research will have to focus on the interactions of different EDCs and their consequences of prenatal and early life exposure.

Associations of gestational phthalate exposure and non-nutritive suck among infants from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) birth cohort study

BACKGROUND

Infant non-nutritive suck (NNS), or sucking on a pacifier with no nutrients being delivered, has been used as in index of brain function and has been linked to subsequent neurodevelopment. Yet, no data are available connecting NNS to environmental exposures in utero. The goal of this study was to examine the relationship between gestational exposure to phthalates (a group of chemicals found in personal care products, PVC plastics, and other products) and NNS among infants in a birth cohort study in Puerto Rico.

METHODS

Urinary phthalate metabolite levels were measured in women at up to three time points in pregnancy as a measure of in utero exposure to the child. We calculated the geometric mean of each metabolite for each woman as a measure of exposure across gestation. Infants had their NNS sampled using our custom research pacifier between 4-6 (± 2 weeks) weeks of age, yielding the following NNS dependent measures: cycles/burst, frequency, amplitude, bursts/min, and cycles/min.

RESULTS

Two hundred and eight mother-infant dyads completed this study We used multiple linear regression to assess associations between individual phthalate metabolites and NNS measurements, adjusting for infant sex, birthweight, and urinary specific gravity. An interquartile range (IQR) increase in mono carboxyisononyl phthalate across pregnancy was associated with 3.5% (95%CI: -6.2, -0.8%) lower NNS frequency and 8.9% (0.6, 17.3%) higher NNS amplitude. Similarly, an IQR increase in mono-2-ethylhexyl phthalate was also associated with 3.4% (-6.5, -0.2%) lower NNS frequency, while an IQR increase in di-2-ethylhexyl terephthalate metabolites was associated with 11.2% (2.9, 19.5%) higher NNS amplitude. Gestational exposure to phthalates may alter NNS amplitude and frequency in full-term infants. These findings indicate that the infants may be increasing their NNS amplitude to compensate for their slower NNS frequency. These preliminary findings could have important clinical implications for earlier detection of exposure-related deficits in neurofunction as well as implications for subsequent neurodevelopment and related interventions.

Exposure to prenatal phthalate mixtures and neurodevelopment in the Conditions Affecting Neurocognitive Development and Learning in Early childhood (CANDLE) study

BACKGROUND

Findings from epidemiological studies of prenatal phthalate exposure and child cognitive development are inconsistent. Methods for evaluating mixtures of phthalates, such as weighted quantile sum (WQS) regression, have rarely been applied. We developed a new extension of the WQS method to improve specificity of full-sample analyses and applied it to estimate associations between prenatal phthalate mixtures and cognitive and language outcomes in a diverse pregnancy cohort.

METHODS

We measured 22 phthalate metabolites in third trimester urine from mother-child dyads who completed early childhood visits in the Conditions Affecting Neurodevelopment and Learning in Early childhood (CANDLE) study. Language and cognitive ability were assessed using the Bayley Scales of Infant Development (age 3) and the Stanford Binet-5 (age 4-6), respectively. We used multivariable WQS regression to identify phthalate mixtures that were negatively and positively associated with language score and full-scale IQ, in separate models, adjusted for maternal IQ, race, marital status, smoking, BMI, socioeconomic status (SES), child age, sex, and breastfeeding. We evaluated effect modification by sex and SES. If full sample 95% WQS confidence intervals (which are known to be anti-conservative) excluded the null, we calculated a p-value using a permutation test (ppermutation). The performance of this new approach to WQS regression was evaluated in simulated data. We compared the power and type I error rate of WQS regression conducted within datasets split into training and validation samples (WQSSplit) and in the full sample (WQSNosplit) to WQS regression with a permutation test (WQSpermutation). Individual metabolite associations were explored in secondary analyses.

RESULTS

The analytic sample (N = 1015) was 62.1% Black/31.5% White, and the majority of mothers had a high school education or less (56.7%) at enrollment. Associations between phthalate mixtures and primary outcomes (language score and full-scale IQ) in the full sample were null. Individual metabolites were not associated with IQ, and only one metabolite (mono-benzyl phthalate, MBzP) was associated with Bayley language score (β = -0.68, 95% CI: -1.37, 0.00). In analyses stratified by sex or SES, mixtures were positively and negatively associated with outcomes, but the precision of full-sample WQS regression results were not supported by permutation tests, with one exception. In the lowest SES category, a phthalate mixture dominated by mono-methyl phthalate (MMP) and mono-carboxy-isooctyl phthalate (MCOP) was associated with higher language scores (βlow SES = 2.41, full-sample 95%CI: 0.58, 4.24; ppermutation = 0.04). Performance testing in simulated data showed that WQSpermutation had improved power over WQSSplit (90% versus 56%) and a lower type I error rate than WQSNosplit (7% versus 47%).

CONCLUSIONS

In the largest study of these relationships to date, we observed predominantly null associations between mixtures of prenatal phthalates and both language and IQ. Our novel extension of WQS regression improved sensitivity to detect true associations by obviating the need to split the data into training and test sets and should be considered for future analyses of exposure mixtures.

Prenatal phthalate exposures and executive function in preschool children

BACKGROUND

Prenatal phthalate exposure has been linked with altered neurodevelopment, including externalizing behaviors and attention-deficit hyperactivity disorder (ADHD). However, the implicated metabolite, neurobehavioral endpoint, and child sex have not always been consistent across studies, possibly due to heterogeneity in neurodevelopmental instruments. The complex set of findings may be synthesized using executive function (EF), a construct of complex cognitive processes that facilitate ongoing goal-directed behaviors. Impaired EF can be presented with various phenotypes of poor neurodevelopment, differently across structured conditions, home/community, or preschool/school. We evaluated the relationship between prenatal phthalate exposure and comprehensive assessment of preschool EF.

METHODS

Our study comprised 262 children with clinically significant/subthreshold ADHD symptoms and 78 typically developing children who were born between 2003 and 2008 and participated in the Preschool ADHD Substudy, which is nested within a population-based prospective cohort study, the Norwegian Mother, Father, and Child Cohort (MoBa). Twelve phthalate metabolites were measured from urine samples that their mothers had provided during pregnancy, at 17 weeks' gestation. All children, at approximately 3.5-years, took part in a detailed clinical assessment that included parent-and teacher-rated inventories and administered tests. We used instruments that measured constructs related to EF, which include a parent-and teacher-reported Behavior Rating Inventory of Executive Function-Preschool (BRIEF-P) and three performance-based tests: A Developmental NEuroPSYchological Assessment (NEPSY), Stanford-Binet intelligence test V (SB5), and the cookie delay task (CDT). The standard deviation change in test score per interquartile range (IQR) increase in phthalate metabolite was estimated with multivariable linear regression. We applied weighting in all models to account for the oversampling of children with clinically significant or subthreshold symptoms of ADHD. Additionally, we assessed modification by child sex and potential co-pollutant confounding.

RESULTS

Elevated exposure to mono-benzyl phthalate (MBzP) during pregnancy was associated with poorer EF, across all domains and instruments, in both sex. For example, an IQR increase in MBzP was associated with poorer working memory rated by parent (1.23 [95% CI: 0.20, 2.26]) and teacher (1.13 [0.14, 2.13]) using BRIEF-P, and administered tests such as SB5 (no-verbal: 0.19 [0.09, 0.28]; verbal: 0.13 [0.01, 0.25]). Adverse associations were also observed for mono-n-butyl phthalate (MnBP) and mono-iso-butyl phthalate (MiBP), although results varied by instruments. EF domains reported by parents using BRIEF-P were most apparently implicated, with stronger associations among boys (e.g., MnBP and inhibition: 2.74 [1.77, 3.72]; MiBP and inhibition: 1.88 [0.84, 2.92]) than among girls (e.g., MnBP and inhibition: -0.63 [-2.08, 0.83], interaction p-value: 0.04; MiBP and inhibition: -0.15 [-1.04, 0.74], interaction p-value: 0.3). Differences by sex, however, were not found for the teacher-rated BRIEF-P or administered tests including NEPSY, SB5, and CDT.

CONCLUSION AND RELEVANCE

Elevated mid-pregnancy MBzP, MiBP, and MnBP were associated with more adverse profiles of EF among preschool-aged children across a range of instruments and raters, with some associations found only among boys. Given our findings and accumulating evidence of the prenatal period as a critical window for phthalate exposure, there is a timely need to expand the current phthalate regulations focused on baby products to include pregnancy exposures.

Urinary phthalate metabolite concentrations and adolescent sleep duration

Some environmental chemicals, such as phthalates, are capable of disrupting endocrine function related to the development and regulation of sleep patterns. However, the contribution of phthalate exposure to inadequate sleep during adolescence is unknown. We aim to evaluate the association between phthalate exposure and short sleep duration during adolescence.

Removal of phthalates from aqueous solution by semiconductor photocatalysis: A review

While phthalate esters are commonly used as plasticizers to improve the flexibility and workability of polymeric materials, their presence and detection in various environments has become a significant concern. Phthalate esters are known to have endocrine-disrupting effects, which affects reproductive health and physical development. As a result, there is now increased focus and urgency to develop effective and energy efficient technologies capable of removing these harmful compounds from the environment. This review explores the use of semiconductor photocatalysis as an efficient and promising solution towards achieving removal and degradation of phthalate esters. A comprehensive review of photocatalysts reported in the literature demonstrates the range of materials including commercial TiO₂, solar activated catalysts and composite materials capable of enhancing adsorption and degradation. The degradation pathways and kinetics are also considered to provide the reader with an insight into the photocatalytic mechanism of removal. In addition, through the use of two key platforms (the technology readiness level scale and electrical energy per order), the crucial parameters associated with advancing photocatalysis for phthalate ester removal are discussed. These include enhanced surface interaction, catalyst platform development, improved light delivery systems and overall system energy requirements with a view towards pilot scale and industrial deployment.

Endocrine-Disrupting Chemicals' (EDCs) Effects on Tumour Microenvironment and Cancer Progression: Emerging Contribution of RACK1

Endocrine disruptors (EDCs) can display estrogenic and androgenic effects, and their exposure has been linked to increased cancer risk. EDCs have been shown to directly affect cancer cell regulation and progression, but their influence on tumour microenvironment is still not completely elucidated. In this context, the signalling hub protein RACK1 (Receptor for Activated C Kinase 1) could represent a nexus between cancer and the immune system due to its roles in cancer progression and innate immune activation. Since RACK1 is a relevant EDCs target that responds to steroid-active compounds, it could be considered a molecular bridge between the endocrine-regulated tumour microenvironment and the innate immune system. We provide an analysis of immunomodulatory and cancer-promoting effects of different EDCs in shaping tumour microenvironment, with a final focus on the scaffold protein RACK1 as a pivotal molecular player due to its dual role in immune and cancer contexts.

Phthalate Exposure, Adolescent Health, and the Need for Primary Prevention

Phthalates, a class of endocrine-disrupting chemicals, are used widely in many consumer products, and exposure can interfere with a range of hormonal functions during early life. These disruptions may alter development during late childhood and adolescence. This article discusses the potential effects of phthalate exposure on adiposity, puberty, and neurodevelopment during late childhood and adolescence. It also highlights studies of behavioral interventions to reduce phthalate exposures and the roles of health care professionals and policy makers in preventing phthalate exposure.

A framework for assessing the impact of chemical exposures on neurodevelopment in ECHO: Opportunities and challenges

The Environmental influences on Child Health Outcomes (ECHO) Program is a research initiative funded by the National Institutes of Health that capitalizes on existing cohort studies to investigate the impact of early life environmental factors on child health and development from infancy through adolescence. In the initial stage of the program, extant data from 70 existing cohort studies are being uploaded to a database that will be publicly available to researchers. This new database will represent an unprecedented opportunity for researchers to combine data across existing cohorts to address associations between prenatal chemical exposures and child neurodevelopment. Data elements collected by ECHO cohorts were determined via a series of surveys administered by the ECHO Data Analysis Center. The most common chemical classes quantified in multiple cohorts include organophosphate pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, environmental phenols (including bisphenol A), phthalates, and metals. For each of these chemicals, at least four ECHO cohorts also collected behavioral data during infancy/early childhood using the Child Behavior Checklist. For these chemicals and this neurodevelopmental assessment (as an example), existing data from multiple ECHO cohorts could be pooled to address research questions requiring larger sample sizes than previously available. In addition to summarizing the data that will be available, the article also describes some of the challenges inherent in combining existing data across cohorts, as well as the gaps that could be filled by the additional data collection in the ECHO Program going forward.

Prenatal phthalate exposure, oxidative stress-related genetic vulnerability and early life neurodevelopment: A birth cohort study

Prenatal phthalate chemicals may have adverse effects on brain development by various mechanisms including oxidant damage. However, birth cohort findings have been conflicting. This study aimed to (i) investigate the interplay between maternal prenatal phthalate levels, infant genetic vulnerability to oxidative stress, and child neurodevelopment and (ii) examine combined putative oxidant exposures. In a population-based birth cohort of 1064 women with prenatal recruitment in Victoria, Australia, maternal urine was collected at 36 weeks of pregnancy and phthalate metabolite concentrations measured. An unweighted genetic score for oxidative stress was made using a candidate gene approach. Cognition was assessed using the BAYLEY-III at two years (n = 678). Parents completed questionnaires for doctor diagnosed autism spectrum disorder (ASD) (1.4 %), ASD traits (4.9 %) and child inattention/hyperactivity (n = 791). Analyses included multiple linear and logistic regression. Higher prenatal phthalate levels and a higher oxidative stress genetic score were each associated with subsequent ASD. Several oxidative stress-related SNPs modified the association between prenatal phthalates and ASD and other outcomes. Consistent patterns were evident across gene score-phthalate combinations for cognition, ASD, ASD traits and inattention/hyperactivity. Other putative oxidant factors such as prenatal smoking further increased risk. Prenatal phthalate levels and infant oxidative stress-related genetic vulnerability are associated with adverse neurodevelopment. Combined exposures are important. Current recommendations and regulation on maternal phthalate exposure during pregnancy require re-evaluation.

Maternal phthalate exposure and asthma, rhinitis and eczema in 552 children aged 5 years; a prospective cohort study

BACKGROUND

Prenatal phthalate exposure has been suggested to alter immune responses and increase the risk of asthma, eczema and rhinitis. However, few studies have examined the effects in prospective cohorts and only one examined rhinitis. We therefore studied associations between maternal urinary concentrations of phthalate metabolites and asthma, eczema and rhinitis in offspring aged 5 years.

METHODS

From 552 pregnant women in the Odense Child Cohort, we quantified urinary concentrations of 12 phthalate metabolites in third trimester. We assessed asthma, rhinitis and eczema in their offspring at age 5 years with a questionnaire based on the International Study of Asthma and Allergies in Childhood (ISAAC), and conducted logistic regression adjusting for relevant confounders.

RESULTS

7.4% of the children had asthma, 11.7% eczema and 9.2% rhinitis. Phthalate exposure was low compared to previous cohorts. No significant associations between prenatal phthalate exposure and asthma were found. Odds ratios (ORs) of child rhinitis with a doubling in ΣDiNP_m and di-2-ethylhexyl phthalate metabolite (ΣDEHP_m) concentrations were, respectively, 1.15 (95% confidence interval (CI) 0.97,1.36) and 1.21 (CI 0.93,1.58). The OR of eczema when doubling ΣDiNP_m was 1.24 (CI 1.00,1.55), whereas the OR of using medicine against eczema when doubling a di-ethyl phthalate (DEP) metabolite was 0.81 (CI 0.68,0.96).

CONCLUSION

The lack of association between maternal phthalate exposure and asthma in the offspring may be due to low exposure and difficulties in determining asthma in 5-year-olds. The higher odds of rhinitis may raise public concern but further research in larger cohorts of older children is warranted.

Influence of Airborne Particles' Chemical Composition on SVOC Uptake from PVC Flooring-Time-Resolved Analysis with Aerosol Mass Spectrometry

We sampled ammonium sulfate particles and indoor particles of outdoor origin through a small chamber covered with polyvinyl chloride flooring. We measured the uptake of semivolatile organic compounds (SVOCs) by the airborne particles in real time. The particles acquired SVOC mass fractions up to 10%. The phthalate ester (di(2-ethylhexyl)phthalate) (DEHP), a known endocrine disruptor, contributed by approximately half of the sorbed SVOC mass. The indoor particles acquired a higher DEHP fraction than laboratory-generated ammonium sulfate aerosol. We attribute this increased uptake to absorption by organic matter present in the indoor particles. Using a thermodenuder to remove volatile components, predominantly organics, reduced the SVOC uptake. Positive matrix factorization applied to the organic mass spectra suggests that hydrocarbon-like organic aerosol (typically fresh traffic exhaust) sorbs DEHP more efficiently than aged organic aerosol. The SVOC uptake is one of the processes that modify outdoor pollution particles after they penetrate buildings, where the majority of exposure occurs. Particles from indoor sources, typically dominated by organic matter, will undergo such processes as well. Aerosol mass spectrometry improves the time resolution of experimental investigations into these processes and enables experiments with lower, relevant particle concentrations. Additionally, particle size-resolved results are readily obtained.

Review of the Effects of Perinatal Exposure to Endocrine-Disrupting Chemicals in Animals and Humans

Maternal exposure to endocrine-disrupting chemicals (EDCs) is associated with long-term hormone-dependent effects that are sometimes not revealed until maturity, middle age, or adulthood. The aim of this study was to conduct descriptive reviews on animal experimental and human epidemiological evidence of the adverse health effects of in utero and lactational exposure to selected EDCs on the first generation and subsequent generation of the exposed offspring. PubMed, Web of Science, and Toxline databases were searched for relevant human and experimental animal studies on 29 October 29 2018. Search results were screened for relevance, and studies that met the inclusion criteria were evaluated and qualitative data extracted for analysis. The search yielded 73 relevant human and 113 animal studies. Results from studies show that in utero and lactational exposure to EDCs is associated with impairment of reproductive, immunologic, metabolic, neurobehavioral, and growth physiology of the exposed offspring up to the fourth generation without additional exposure. Little convergence is seen between animal experiments and human studies in terms of the reported adverse health effects which might be associated with methodologic challenges across the studies. Based on the available animal and human evidence, in utero and lactational exposure to EDCs is detrimental to the offspring. However, more human studies are necessary to clarify the toxicological and pathophysiological mechanisms underlying these effects.

The association between prenatal exposure to phthalates and cognition and neurobehavior of children-evidence from birth cohorts

BACKGROUND

Phthalate have been detected widely in the environment; while several studies have indicated that prenatal phthalate exposure has adverse effects on neurodevelopment, the results were inconsistent.

OBJECTIVE

We aimed to determine the current research status of the relationship between prenatal exposure to different types of phthalate and cognition and behavioral development in children. We conducted a systematic review to evaluate the current state of knowledge.

METHODS

We systematically searched PubMed, Web of Science, and EMBASE electronic databases up to May 2018 with manual searches of the references of retrieved publications and relevant reviews. Only birth cohort studies that reported on the association between phthalate exposure and cognitive or behavioral development were included in this review. We evaluated the risk of bias for each of the included studies using a modified instrument based on the Cochrane Collaboration's "Risk of Bias" tool.

RESULT

Twenty-six birth cohort studies met our inclusion criteria, nine of which investigated the impact of phthalate exposure during pregnancy on cognition, 13 on neurobehavior, and 4 on both cognition and neurobehavior. However, ten articles reported that the effect of prenatal exposure to phthalates on cognitive development was statistically significant, 15 articles reported that the effect of prenatal exposure to phthalates on neurobehavior was statistically significant. The effect of prenatal phthalate exposure on neurodevelopment differed according to sex, but the results are inconsistent, for instance, among the five studies investigating the association between mental development index (MDI) and Mono-n-butyl phthalate (MnBP), two of them showed a significantly decreasing MDI scores with increasing concentrations of MnBP among girls, but among boys one study showed the inverse association, another showed the positive association.

CONCLUSION

Di(2-ethylhexyl) phthalate, dibutyl phthalate, butyl-benzyl phthalate and di-ethyl phthalate exposure during pregnancy was associated with lower cognitive scores and worse behavior in offspring, and sex-specific effects on cognitive, psychomotor, and behavioral development were identified, especially the impact of phthalate exposure on neurobehavior in boys.

Prenatal bisphenol A exposure is associated with language development but not with ADHD-related behavior in toddlers from the Odense Child Cohort

Bisphenol A (BPA) is a non-persistent chemical with endocrine disrupting abilities widely used in a variety of consumer products. The fetal brain is particularly sensitive to chemical exposures due to its rapid growth and complexity. Some studies have reported associationbetween maternal BPA exposure and behavior but few have assessed impact on cognitive development, and to our knowledge no studies have specifically assessed the impact on language development. We therefore assessed whether maternal urinary BPA concentration during pregnancy was associated with language development and attention-deficit and hyperactivity disorder (ADHD) symptoms in offspring aged 18-36 months in the prospective Odense Child Cohort. BPA was analyzed in 3rd trimester maternal fasting urine spot samples. Language development was addressed among 535 children using the Danish adaptation of the MacArthur-Bates Communicative Development Inventories at median age 21 months; ADHD traits were assessed by parents of 658 children using the Child Behavior Checklist for ages 1½-5 years at mean age 2.7 years. Associations were assessed using logistic regression models comparing children below the 15th percentile score for language and above the 85 percentiles score for ADHD with the other children while stratifying by sex and adjusting for maternal education, duration of breastfeeding and maternal urine phthalates. BPA was detected in 85.3% of the urine samples (median 1.2 ng/ml). Boys of mothers with BPA exposure in the highest tertile had an odds ratio of 3.70 (95% CI 1.34-10.21) of being in the lowest 15th percentile of vocabulary score compared to boys of mothers within the lowest tertile of BPA exposure after adjustment, whereas no association was found in girls. No clear dose-response relationship between maternal BPA and ADHD scores above the 85th percentile was found for either sex. Since early language development is a predictor of future reading skills and educational success, more epidemiological studies assessing BPA exposure and language skills are needed to confirm our findings.

Combined use of vitamin E and nimodipine ameliorates dibutyl phthalate-induced memory deficit and apoptosis in mice by inhibiting the ERK 1/2 pathway

Learning disabilities (LDs) in children are a serious global problem. Dibutyl phthalate (DBP), a plasticizer widely used in daily life, has been linked to triggering childhood LDs, however the mechanism underlying this remains unclear. Studies have shown that the ERK 1/2 pathway is closely related to apoptosis of hippocampal neurons. On the basis of these links between LDs, DBP and the ERK 1/2 pathway, we explore whether DBP induces hippocampal neuron apoptosis and increases behavioral disorders in mice via the ERK 1/2 pathway. We looked at oxidative stress, examined the calcium signal, detected the ERK 1/2 pathway and evaluated apoptosis as well as using histological observations, and found that DBP significantly increased oxidative damage and apoptosis in hippocampal neurons via the ERK 1/2 pathway in mice. We also found that pretreatment with the dihydropyridine's (DHP's) Ca²⁺ antagonist, nimodipine (NMDP), combined with the antioxidant Vitamin E (VE), attenuated ERK 1/2 phosphorylation and DBP-mediated disorders, suggesting that a combined use of VE and NMDP can ameliorate DBP-induced memory deficit and apoptosis via inhibiting the ERK 1/2 pathway. These results indicate that DBP predisposes oxidative damage and apoptosis in hippocampal neurons by activation of the ERK 1/2 pathway, and may be proposed as a possible mechanism underlying LDs in children. Moreover, VE and NMDP may play a certain protective role in the targeted treatment of childhood LDs.

Association of Prenatal Phthalate Exposure With Language Development in Early Childhood

IMPORTANCE

Prenatal exposure to phthalates has been associated with neurodevelopmental outcomes, but little is known about the association with language development.

OBJECTIVE

To examine the association of prenatal phthalate exposure with language development in children in 2 population-based pregnancy cohort studies.

DESIGN, SETTING, AND PARTICIPANTS

Data for this study were obtained from the Swedish Environmental Longitudinal Mother and Child, Asthma and Allergy (SELMA) study conducted in prenatal clinics throughout Värmland county in Sweden and The Infant Development and the Environment Study (TIDES) conducted in 4 academic centers in the United States. Participants recruited into both studies were women in their first trimester of pregnancy who had literacy in Swedish (SELMA) or English or Spanish (TIDES). This study included mothers and their children from both the SELMA study (n = 963) and TIDES (n = 370) who had complete data on prenatal urinary phthalate metabolite levels, language delay, and modeled covariables. For SELMA, the data were collected from November 1, 2007, to June 30, 2013, and data analysis was conducted from November 1, 2016, to June 30, 2018. For TIDES, data collection began January 1, 2010, and ended March 29, 2016, and data analysis was performed from September 15, 2016, to June 30, 2018.

MAIN OUTCOMES AND MEASURES

Mothers completed a language development questionnaire that asked the number of words their children could understand or use at a median of 30 months of age (SELMA) and 37 months of age (TIDES). The responses were categorized as fewer than 25, 25 to 50, and more than 50 words, with 50 words or fewer classified as language delay.

RESULTS

In the SELMA study, 963 mothers, 455 (47.2%) girls, and 508 (52.8%) boys were included. In TIDES, 370 mothers, 185 (50.0%) girls, and 185 (50.0%) boys were included in this analysis. The prevalence of language delay was 10.0% in both SELMA (96 reported) and TIDES (37 reported), with higher rates of delay in boys than girls (SELMA: 69 [13.5%] vs 27 [6.0%]; TIDES: 23 [12.4%] vs 14 [7.6%]). In crude analyses, the metabolite levels of dibutyl phthalate and butyl benzyl phthalate were statistically significantly associated with language delay in both cohorts. In adjusted analyses, a doubling of prenatal exposure of dibutyl phthalate and butyl benzyl phthalate metabolites increased the odds ratio (OR) for language delay by approximately 25% to 40%, with statistically significant results in the SELMA study (dibutyl phthalate OR, 1.29 [95% CI, 1.03-1.63; P = .03]; butyl benzyl phthalate OR, 1.26 [95% CI, 1.07-1.49; P = .003]). A doubling of prenatal monoethyl phthalate exposure was associated with an approximately 15% increase in the OR for language delay in the SELMA study (OR, 1.14; 95% CI, 1.00-1.31; P = .05), but no such association was found in TIDES (OR, 0.98; 95% CI, 0.79-1.23).

CONCLUSIONS AND RELEVANCE

In findings from this study, prenatal exposure to dibutyl phthalate and butyl benzyl phthalate was statistically significantly associated with language delay in children in both the SELMA study and TIDES. These findings, along with the prevalence of prenatal exposure to phthalates, the importance of language development, and the inconsistent results from a 2017 Danish study, suggest that the association of phthalates with language delay may warrant further examination.

Inhalation and Dermal Uptake of Particle and Gas-Phase Phthalates-A Human Exposure Study

Phthalates are ubiquitous in indoor environments, which raises concern about their endocrine-disrupting properties. However, studies of human uptake from airborne exposure are limited. We studied the inhalation uptake and dermal uptake by air-to-skin transfer with clean clothing as a barrier of two deuterium-labeled airborne phthalates: particle-phase D₄-DEHP (di(2-ethylhexyl)phthalate) and gas-phase D₄-DEP (diethyl phthalate). Sixteen participants, wearing trousers and long-sleeved shirts, were under controlled conditions exposed to airborne phthalates in four exposure scenarios: dermal uptake alone and combined inhalation + dermal uptake of both phthalates. The results showed an average uptake of D₄-DEHP by inhalation of 0.0014 ± 0.00088 (μg kg^-1 bw)/(μg m^-3)/h. No dermal uptake of D₄-DEHP was observed during the 3 h exposure with clean clothing. The deposited dose of D₄-DEHP accounted for 26% of the total inhaled D₄-DEHP mass. For D₄-DEP, the average uptake by inhalation + dermal was 0.0067 ± 0.0045 and 0.00073 ± 0.00051 (μg kg^-1 bw)/(μg m^-3)/h for dermal uptake. Urinary excretion factors of metabolites after inhalation were estimated to 0.69 for D₄-DEHP and 0.50 for D₄-DEP. Under the described settings, the main uptake of both phthalates was through inhalation. The results demonstrate the differences in uptake of gas and particles and highlight the importance of considering the deposited dose in particle uptake studies.