Association of both prenatal and early childhood multiple metals exposure with neurodevelopment in infant: A prospective cohort study

Prenatal exposure to metal mixture and birth weight; a Bayesian kernel machine regression analysis of two cohort studies in Japan and Iran

Purpose

Potentially toxic metals can directly induce various adverse effects on reproductive organs or interrupt essential metals' physiological activities. Despite intensive efforts to reduce these metals in the environment, chronic and low-level exposure remains a public health problem. The present study aimed to investigate prenatal metal exposure, including arsenic (As), copper (Cu), lead (Pb), manganese (Mn), rubidium (Rb), selenium (Se), and zinc (Zn), effects on birth weight.

Methods

We collected 579 blood samples before the 16th week of gestation from apparently healthy women with singleton pregnancy in Iran (n = 193) and Japan (n = 386). Blood metal concentrations were measured using inductively coupled plasma-mass spectrometry.

Results

Prenatal blood levels of As, Mn, Pb, and Zn were significantly higher, while Cu, Rb, and Se were significantly (p < 0.01) lower in Iranian participants than in Japanese. Adjusted linear regression analyses and Bayesian Kernel Machine Regression (BKMR) overall exposure-response functions showed inverse relationships between metals and birth weight.

Conclusion

The study findings, using data from geographically diverse countries, suggest prenatal blood metal exposure as a potential risk factor for lower birth weight. Therefore, women of reproductive age should minimize encountering to potentially toxic metals as much as possible.

Association between epigenome-wide DNA methylation changes and early neurodevelopment in preschool children: Evidence from a former impoverished county in Central China

BACKGROUND

Existing epigenome-wide association studies (EWAS) investigating the association between DNA methylation (DNAm) and child neurodevelopment have been predominantly conducted within Western populations, and yielded inconsistent results, leading to a significant gap within non-Western setting, particularly in resource-limited rural areas of Central China.

OBJECTIVES

To investigate the association between altered epigenome-wide DNAm and neurodevelopment in preschool children from resource-limited rural areas of Central China.

METHODS

This case-control study involved 64 preschoolers. We assessed children's neurodevelopment using the Gesell Developmental Diagnostic Scale. The neurodevelopmental potential was expressed as a global developmental quotient (DQ) score. We conducted an EWAS with an Illumina Infinium MethylationEPIC v1.0 BeadChip array, using blood samples from 32 suspected developmental delay children (DQ scores < 85) and 32 controls (DQ scores ≥ 85). Differentially methylated probes (DMPs) and differentially methylated regions (DMRs) between the suspected developmental delay and control groups were analyzed. Multivariate linear regression models were used to evaluate the association between global DQ scores and DNAm. Functional enrichment analyses were conducted using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). The BECon tool was utilized to estimate the concordance of CpGs between blood and the human brain.

RESULTS

A total of 66 DMRs (PFDR < 0.05) were identified between the two groups, but no DMPs were found. After FDR correction, 844 methylated CpG sites exhibited significant associations with the global DQ scores in children. Genes annotated by methylated CpGs were mainly enriched in the "oxytocin signaling pathway", "mTOR signaling pathway", and "thyroid hormone signaling pathway". They were also involved in the "regulation of cell development", "cell-cell junction", and "ATPase activity". Among the top 20 CpGs, nine global DQ scores related-CpGs had blood-brain DNA methylation correlations, and six CpGs among them had an absolute Spearman correlation coefficient bigger than 0.2.

CONCLUSIONS

Preschoolers from a former impoverished county exhibited epigenome-wide DNAm changes strongly linked to early neurodevelopment. This study enhances our understanding of the epigenetic landscape associated with early neurodevelopment, and suggests the potential for developmenting epigenetic biomarkers that could facilitate the early identification of children at a higher risk of compromised neurodevelopment, as well as holding implication to inform novel interventions, especially in underprivileged regions.

Associations of prenatal metal exposure with child neurodevelopment and mediation by perturbation of metabolic pathways

Prenatal exposure to metals has been associated with impaired neurodevelopment in children, but the detailed molecular mechanisms remain largely unknown. Based on the Wuhan Healthy Baby Cohort, China (N = 1088), eleven metals were measured in maternal urine during early pregnancy (13.1 ± 1.1 weeks) and metabolomics profiling was conducted in cord blood. Neurodevelopment was evaluated using the Bayley Scales of Infant Development in 2-year-old children to obtain the mental development index (MDI) and psychomotor development index (PDI). After false discovery rate correction, higher maternal urinary levels of manganese, nickel, aluminum, rubidium, gallium, and the summary score of metals were only significantly associated with lower MDI scores. The weighted quantile sum index of the metal mixture showed a significant inverse association with MDI and PDI scores, with aluminum contributing the most to the associations. Histidine, beta-alanine, purine, and pyrimidine metabolism significantly mediated the above associations, suggesting that disturbances in amino acids, neurotransmitter and neuroendocrine metabolism may be important mediators in contributing to impaired neurodevelopment of children.

Altered monocyte subpopulations and their association with autism spectrum disorder risk in children

OBJECTIVE

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficits in social communication, restricted interests, and repetitive behaviors. Emerging evidence suggests a link between immune dysregulation and ASD. This study investigates alterations in monocyte subpopulations and cytokine production in children with ASD and their potential associations with ASD risk and severity.

METHODS

Initially, the immune status of peripheral blood mononuclear cells was assessed in cohort-I of 96 typically developing (TD) children and 92 children diagnosed with ASD using flow cytometry. Subsequently, the secretion of cytokines IL-6 and IL-10 by monocytes was evaluated following stimulation with a leukocyte activation mixture and intracellular protein staining technique in cohort-II.

RESULTS

Children with ASD exhibited significantly higher levels of total monocytes, classical monocytes (CD14hi/CD16-), and non-classical monocytes (CD14low/CD16+) compared to TD children (p < 0.001). Elevated levels of classical monocytes (β: 0.395; 95 %CI: 0.260-0.530; p < 0.001) and non-classical monocytes (β: 0.629; 95 %CI: 0.516-0.742; p < 0.001) were significantly associated with ASD after adjusting for age, sex and body mass index. Furthermore, increased production of IL-6 by monocytes was observed in children with ASD (p = 0.001). Logistic regression analysis revealed that classical monocytes (OR: 1.104; 95 %CI: 1.062-1.147; p < 0.001), non-classical monocytes (OR: 2.913; 95 %CI: 2.130-3.986; p < 0.001) and IL-6 production by monocytes (OR: 1.306; 95 %CI: 1.096-1.557; p = 0.003) are risk factors for ASD. Spearman correlation analysis revealed a negative correlation between classical monocyte levels and adaptive behavior developmental quotient (DQ) (r = - 0.377; p = 0.001), fine motor DQ (r = - 0.329; p = 0.003) and personal-social DQ (r = - 0.247; p = 0.029) in children with ASD.

CONCLUSION

Elevated classical and non-classical monocytes are potential risk factors for ASD and may influence neurodevelopmental outcomes. Further research is needed to elucidate the precise mechanisms and therapeutic implications.

Effects of prenatal exposure to multiple heavy metals on infant neurodevelopment: A multi-statistical approach

Prenatal exposure to heavy metals poses risks to fetal brain development, yet the joint effects of these metals remain unclear, with inconsistent findings across statistical models. This study investigates the joint effect of prenatal exposure to cadmium (Cd), nickel (Ni), mercury (Hg), and lead (Pb) on infant neurodevelopment using various statistical approaches. The study included 400 mother-infant pairs. Heavy metal levels were measured in maternal urine samples at the 12th week of gestation, and infant neurodevelopment at 40 days was evaluated by the Bayley Scales of Infant and Toddler Development. Generalized Additive Models (GAM), Multivariable Linear Regression (MLR) with restricted cubic spline (RCS), Bayesian Kernel Machine Regression (BKMR), and Weighted Quantile Sum (WQS) regression were applied to explore the associations between heavy metal exposure and neurodevelopmental outcomes. GAM revealed a significant linear relationship for Cd with cognitive scale (p = 0.045) and expressive language (p = 0.043). MLR confirmed that Cd was negatively associated with both cognitive scale (β = -1.47, p = 0.044) and expressive language (β = -0.32, p = 0.019) and RCS presented a non-linear association between Pb and language scale (p = 0.001). BKMR suggested a negative but non-significant association with most outcomes. WQS indicated a significant adverse effect of metal mixture on expressive language (β = -0.26, 95% CI = -0.44, -0.07), identifying Cd and Ni as the primary contributors. Prenatal exposure to heavy metals have detrimental effects on infant neurodevelopment, especially on language development.

Copper and zinc status in cord blood and breast milk and child's neurodevelopment at 18 months: Results of the Italian PHIME cohort

BACKGROUND

Trace elements, including zinc (Zn) and copper (Cu), although toxic at higher concentrations are known to play important roles in the maintenance of human health and neurodevelopment. Few epidemiological studies have investigated the association between prenatal or early postnatal Cu and Zn levels and child neurodevelopment. The aim of this research is to assess the association between child neurodevelopment at 18 months of age and cord blood and breast milk concentrations of Cu and Zn in Italian mother-child pairs enrolled in the Italian Northern Adriatic Cohort II (NAC-II), a part of the "Public health impact of long-term, low-level, mixed element exposure in susceptible population strata" project PHIME.

METHODS

The study population consisted of 632 children, and their mothers, born within the NAC-II, who were tested with the Bayley Scales of Infant and Toddler Development third edition (BSID-III) at age 18 months. Cu and Zn concentrations were measured in cord blood and breast milk samples. Only children born at term (≥37 gestational week), who completed the BSID-III test and had at least 1 measure of Cu and Zn concentrations were included in the analysis. Information about socio-demographics and lifestyles were collected through questionnaires at different phases of follow-up. Cu and Zn concentrations were log2 transformed because of their skewed distribution. Multiple linear regression models were performed to study the association between each BSID-III composite score (cognitive, motor and language) and each metal concentration. Separate models were applied for each biological sample. The β coefficient (β) and its 95% confidence interval (95% CI) were estimated. Stratified analyses by child's sex were also conducted.

RESULTS

The mean ± standard deviation (SD) of cognitive, motor and language composite scores were respectively: 106 ± 8, 101 ± 5 and 97 ± 8. The mean ± SD of Cu and Zn concentrations (ng/g) were respectively 699.2 ± 129.0 and 2538 ± 589 in cord blood and 607 ± 498 and 3226 ± 1428 in breast milk. No association between metal concentration and cognitive composite score was found. A higher motor composite score was associated with higher Cu concentrations in cord blood (β = 4.31 95% CI 2.03; 6.59). No associations were found between language composite score and metal concentrations. The effect of Cu cord blood concentration on motor composite score was confirmed when stratified by sex: males (β = 5.49 95% CI 2.15; 8.36) and females (β = 3.11; 95% CI 0.00; 6.22). A direct association, in females only, was found between language composite score and Cu concentration in cord blood (β = 5.60 95% CI 0.63; 10.57) and in breast milk (β = 3.04 95% CI 1.06; 5.03), respectively.

CONCLUSION

The results from this cohort study showed a strong direct association between prenatal Cu levels and child motor neurodevelopment at 18 months. However, for generalizability, future research on the effects of Zn and Cu on neurodevelopment should include a larger range of early-life concentration of trace elements.

Associations of gestational and childhood exposure to lead, cadmium, and fluoride with cognitive abilities, behavior, and social communication at 4 years of age: NICE birth cohort study

BACKGROUND

Early-life lead exposure affects cognitive development and emerging evidence suggests similar effects of cadmium and fluoride.

OBJECTIVE

To assess the impact of gestational and childhood exposure to lead, cadmium, and fluoride on cognitive abilities and behavioral and social communication problems.

METHODS

We studied 470 pregnant women (gestational week 29) and their 4-year-old children from the NICE cohort in northern Sweden. Concentrations of erythrocyte lead and cadmium and urinary cadmium were measured using inductively coupled plasma mass spectrometry and urinary fluoride with an ion-selective electrode. Urinary concentrations were specific-gravity adjusted. Associations of log2-transformed exposure concentrations with cognitive abilities (full-scale IQ and verbal comprehension by Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition), behavioral problems (Child Behavior Checklist), and social communication (Social Responsiveness Scale-Second Edition) were evaluated with multivariable-adjusted linear regression analysis.

RESULTS

Both gestational and cord erythrocyte lead concentrations were non-significantly inversely associated with child cognitive abilities (full-scale IQ: B [95%CI]: -1.2 [-2.9, 0.5] and -1.6 [-3.7, 0.4], respectively; per doubling of exposure). Similarly, both gestational and child urinary cadmium were inversely associated with cognitive abilities (full-scale IQ: -1.1 [-2.5, 0.3] and -1.1 [-2.5, 0.4], verbal comprehension: -1.2 [-3.1, 0.6] and -1.4 [-3.4, 0.6], respectively). Urinary fluoride concentrations showed no association with cognitive abilities. However, gestational fluoride was associated with increasing externalizing problems (0.9 [-0.3, 2.0]) and ADHD raw scores (0.3 [0.0, 0.6]). Childhood erythrocyte lead and urinary cadmium were non-significantly associated with increased behavioral problems (lead with total problems: 1.2 [-0.4, 2.9] and internalizing problems: 1.5 [-0.4, 3.4]; cadmium with externalizing problems: 1.1 [-0.2, 2.4]).

CONCLUSION

Despite non-significant associations, both lead and cadmium exposure showed consistent inverse associations with cognitive abilities at 4 years, whereas associations with behavioral problems were less conclusive, especially for cadmium. Results on fluoride indicated association with externalizing problems, including ADHD, but prevalence of behavioral problems was low, increasing uncertainty.

Zinc Mitigates the Combined Neurotoxicity of Binary Metal Mixtures via Mitophagy and Mitochondrial Fusion

Environmental metal mixtures can cause combined neurotoxicity, but the underlying mechanism remains unclear. Mitochondria are crucial for energy metabolism in the nervous system, and their dysfunction leads to neurodegeneration. Zinc (Zn) is a coenzyme of many mitochondrial enzymes that controls mitochondrial function. This study investigated the role of Zn in the neurotoxicity induced by Mn + Pb and Pb + As mixtures. Zn supplementation improved the survival rate and learning ability of Caenorhabditis elegans following their exposure to mixtures of Mn + Pb and Pb + As by enhancing their mitochondrial morphology, membrane potential, and respiratory chain. Similarly, in HT22 cells, Zn mitigated the decrease in cellular activity and increase in apoptosis induced by the Mn + Pb and Pb + As mixtures by improving mitochondrial morphology and function. Mechanistically, Zn activated the PINK1 and MFN-2/OPA-1 pathways, promoting mitophagy and mitochondrial fusion. However, inhibition of mitophagy reversed the protective effect of Zn, indicating its reliance on mitophagy for neuroprotection. Our study demonstrated that Zn alleviates the combined neurotoxicity of Mn + Pb and Pb + As mixtures by enhancing mitophagy and mitochondrial fusion, suggesting that Zn supplementation is a potential treatment for metal-induced neurotoxicity.

The global issue of metal contamination in sharks, rays and skates and associated human health risks

Elasmobranchs, including sharks, rays, and skates, are a global protein source but face threats from overfishing and population declines. Despite their lower market value, increased consumption raises sustainability and public health concerns. Commonly landed species like the Blue Shark, Shortfin Mako, and Spiny Dogfish are particularly vulnerable to bioaccumulation of metals such as mercury (Hg), lead (Pb), cadmium (Cd), and arsenic (As), posing health risks to consumers. Although metal and metalloid contamination levels in elasmobranchs are frequently reported, studies on specific human health risks remain limited. Sensitive populations, including pregnant women, fetuses, infants, the elderly, and individuals with pre-existing health conditions, face elevated risks from consuming contaminated seafood. Vulnerable communities, especially coastal populations and lower-income groups, encounter further exposure risks due to limited access to safer food alternatives and information. This review explores metal and metalloid contamination in commonly consumed elasmobranch species, associated health risks, and impacts on vulnerable groups, emphasizing the need for informed consumption and the role of contamination awareness in conservation efforts. Arsenic was the most commonly detected element in elasmobranch meat, followed by Se, Hg, Pb, and Cd, with Pb and Se consistently reported at safe levels. Arsenic levels exceeded safety thresholds in most studies, posing health risks, while THQ evaluations indicated significant risks, especially in sharks, where values often surpassed safe thresholds. For C. falciformis, THQ ranged from 5.7 in North America to 38 in Asia, making the consumption of this species inadvisable. Elevated HQ values suggest that cumulative risks likely exceed safe limits, highlighting the need for cautious consumption and further risk assessments.

Early postnatal and concurrent exposure to metals and neurobehavioral outcomes at 5 years: Associations with individual environmental exposures and mixtures

BACKGROUND

Little is known about the effect of postnatal exposure to heavy metals on children's behavior problems. This study aimed to investigate the association between metal exposure during different stages of postnatal life and neurobehavioral outcomes in preschool children.

METHODS

Urinary concentrations of six metals (arsenic, cadmium, chromium, lead, manganese, and vanadium) were measured using inductively coupled plasma mass spectrometry in 220 participants at two time points: before 1 year and at 5 years of age. Mothers completed the Child Behavior Checklist when the children were 5 years old. Multivariable linear and logistic regression analyses were used to evaluate the association between metal concentrations and behavioral outcomes. We employed Bayesian kernel machine regression (BKMR) to assess possible joint effects and potential interactions between metal mixtures and behavioral outcomes.

RESULTS

Concentrations of urinary arsenic (As) in infants were associated with higher scores for anxious/shy behavior problems (β ranging from 0.03 to 0.23). Further analyses showed that As exposure increased the odds of scores falling into the borderline or clinical range on anxious/depressed, affective, and pervasive developmental problems (ORs: 2.45-3.40). Stratification by sex indicated significance in girls but not in boys. BKMR analysis showed that, among the metal mixtures, As displayed a major effect on behavior scores. Concentrations of urinary cadmium in infants were also associated with higher behavioral scores but did not increase the risk of clinical problems. A cross-sectional survey in 5-year-olds did not show a significant association between concurrent metal exposure and behavioral outcome.

CONCLUSION

Our results showed that exposure to As and Cd during infancy was associated with emotional problems in children. The effect of arsenic exposure was more pronounced among female infants. We suggest reducing exposure to toxic metals during early postnatal life to prevent behavioral problems in children."

Association between maternal metal exposure during early pregnancy and intelligence in children aged 3-6 years: Results from a Chinese birth cohort

OBJECTIVE

Maternal environmental metal exposure is common, but long-term prospective epidemiological evidence of its impact on children's intellectual development is still insufficient.

METHODS

Data on maternal plasma metal levels and child intelligence were obtained for 211 3-6-year-old children from Guangxi Zhuang Birth Cohort. ICP-MS was employed to detect 17 metals, including 7 essential metals (Mn, Fe, Co, Ni, Cu, Zn, Mo) and 10 non-essential metals (As, Rb, Sr, Cd, Sb, Cs, Ba, W, Pb, U), in maternal plasma samples obtained before 13 weeks of gestation during the initial maternity checkup. Child intelligence was assessed using the Wechsler Intelligence Scale for Children-Fourth Edition. The GLM, RCS and mixture models were used to assess the associations of maternal plasma metal levels with child intelligence quotient (IQ) scores.

RESULTS

The GLM analysis revealed that U had a significant adverse effect on child IQ scores in high-dose exposure groups (-9.236 [-18.644, -4.936], p = 0.006) after adjusting for covariates, while Sb showed a linear adverse effect on children's intelligence in the adjusted model (-4.028 [-7.432, -0.626], p = 0.021). BKMR modeling indicated that overall IQ scores decreased as concentrations of non-essential metals mixtures increased after adjusting for essential metal mixtures, consistent with findings from the WQS (β [95% CI], -8.463 [-14.449, -2.476], p = 0.007) and Qgcomp models (-7.003 [-12.928, -1.078], p = 0.022). Among the non-essential metals, U had the highest negative weight at 37.96%, followed by Pb (23.35%) and Sb (16.91%). Furthermore, potential interactions were observed between metals (Pb and U) and Sb in the study findings.

CONCLUSION

Reducing exposure to non-essential metal mixtures, especially U, Sb and Pb, during early pregnancy and ensuring adequate intake of specific essential metal elements could be a critical intervention in addressing childhood intellectual impairment.

Association of prenatal multiple metal exposures with child neurodevelopment at 3 years of age: A prospective birth cohort study

Prenatal exposures to toxic metals and trace elements have been linked to childhood neurodevelopment. However, existing evidence remains inconclusive, and further research is needed to investigate the mixture effects of multiple metal exposures on childhood neurodevelopment. We aimed to examine the associations between prenatal exposure to specific metals and metal mixtures and neurodevelopment in children. In this prospective cohort study, we used the multivariable linear regressions and the robust modified Poisson regressions to explore the associations of prenatal exposure to 25 specific metals with neurodevelopment among children at 3 years of age in 854 mother-child pairs from the Jiangsu Birth Cohort (JBC) Study. The Bayesian kernel machine regression (BKMR) was employed to assess the joint effects of multiple metals on neurodevelopment. Prenatal manganese (Mn) exposure was negatively associated with the risk of non-optimal cognition development of children, while vanadium (V), copper (Cu), zinc (Zn), antimony (Sb), cerium (Ce) and uranium (U) exposures were positively associated with the risk of non-optimal gross motor development. BKMR identified an interaction effect between Sb and Ce on non-optimal gross motor development. Additionally, an element risk score (ERS), representing the mixture effect of multiple metal exposures including V, Cu, Zn, Sb, Ce and U was constructed based on weights from a Poisson regression model. Children with ERS in the highest tertile had higher probability of non-optimal gross motor development (RR = 2.37, 95 % CI: 1.15, 4.86) versus those at the lowest tertile. Notably, Sb [conditional-posterior inclusion probabilities (cPIP) = 0.511] and U (cPIP = 0.386) mainly contributed to the increased risk of non-optimal gross motor development. The findings highlight the importance of paying attention to the joint effects of multiple metals on children's neurodevelopment. The ERS score may serve as an indicator of comprehensive metal exposure risk for children's neurodevelopment.

Transcriptomic evaluation of metals detected in placenta

This research aims to assess the concentration of metals in human and canine placentas from the same geographic area and to investigate how these metal levels influence gene expression within the placenta. Placentas of 25 dogs and 60 women who had recently given birth residing in Ankara, Turkey were collected and subjected to metal analysis using ICP-OES. Placentas with detectable metal levels underwent further examination including Next Generation Sequencing, transcriptional analysis, single nucleotide polymorphism investigation, and extensive scrutiny across various groups. For women, placentas with concurrent detection of aluminum (Al), lead (Pb), and cadmium (Cd) underwent transcriptomic analysis based on metal analysis results. However, the metal load in dog placentas was insufficient for comparison. Paired-end sequencing with 100-base pair read lengths was conducted using the DNBseq platform. Sequencing quality control was evaluated using FastQC, fastq screen, and MultiQC. RNA-sequencing data is publicly available via PRJNA936158. Comparative analyses were performed between samples with detected metals and "golden" samples devoid of these metals, revealing significant gene lists and read counts. Normalization of read counts was based on estimated size factors. Principal Component Analysis (PCA) was applied to all genes using rlog-transformed count data. Results indicate that metal exposure significantly influences placental gene expression, impacting various biological processes and pathways, notably those related to protein synthesis, immune responses, and cellular structure. Upregulation of immune-related pathways and alterations in protein synthesis machinery suggest potential defense mechanisms against metal toxicity. Nonetheless, these changes may adversely affect placental function and fetal health, emphasizing the importance of monitoring and mitigating environmental exposure to metals during pregnancy.

A single-cell transcriptomic landscape of cadmium-hindered brain development in mice

The effects of neurotoxicant cadmium (Cd) exposure on brain development have not been well elucidated. To investigate this, we have herein subjected pregnant mice to low-dose Cd throughout gestation. Using single-cell RNA sequencing (scRNA-seq), we explored the cellular responses in the embryonic brain to Cd exposure, and identified 18 distinct cell subpopulations that exhibited varied responses to Cd. Typically, Cd exposure impeded the development and maturation of cells in the brain, especially progenitor cells such as neural progenitor cells (NPCs) and oligodendrocyte progenitor cells (OPCs). It also caused significant cell subpopulation shifts in almost all the types of cells in the brain. Additionally, Cd exposure reduced the dendritic sophistication of cortical neurons in the offspring. Importantly, these changes led to aberrant Ca2+ activity in the cortex and neural behavior changes in mature offspring. These data contribute to our understanding of the effects and mechanisms of Cd exposure on brain development and highlight the importance of controlling environmental neurotoxicant exposure at the population level.

Prenatal Parental Exposure to Metals and Birth Defects: A Prospective Birth Cohort Study

While maternal exposure to high metal levels during pregnancy is an established risk factor for birth defects, the role of paternal exposure remains largely unknown. We aimed to assess the associations of prenatal paternal and maternal metal exposure and parental coexposure with birth defects in singletons. This study conducted within the Jiangsu Birth Cohort recruited couples in early pregnancy. We measured their urinary concentrations for 25 metals. A total of 1675 parent-offspring trios were included. The prevalence of any birth defects among infants by one year of age was 7.82%. Paternal-specific gravity-corrected urinary concentrations of titanium, vanadium, chromium, manganese, cobalt, nickel, copper, and selenium and maternal vanadium, chromium, nickel, copper, selenium, and antimony were associated with a 21-91% increased risk of birth defects after adjusting for covariates. These effects persisted after mutual adjustment for the spouse's exposure. Notably, when assessing the parental mixture effect by Bayesian kernel machine regression, paternal and maternal chromium exposure ranked the highest in relative importance. Parental coexposure to metal mixture showed a pronounced joint effect on the risk of overall birth defects, as well as for some specific subtypes. Our findings suggested a couple-based prevention strategy for metal exposure to reduce birth defects in offspring.

Association of metals with early postnatal gut microbiota among infants admitted to the neonatal intensive care unit

The gut microbiota is closely related to infant health. However, the impact of environmental factors on the gut microbiota has not been widely investigated, particularly in vulnerable populations such as infants admitted to the neonatal intensive care unit (NICU). This study investigated the association between exposure to 12 metals and the composition of the gut microbiota in infants admitted to the NICU. Metal concentrations were determined in serum samples obtained from 107 infants admitted to the NICU at Hunan Children's hospital, China. Gut microbiota data were derived from 16S rRNA sequencing using stool samples. Generalized linear regression (GLR) models and Bayesian kernel machine regression (BKMR) analyses were used to estimate the associations between metals and both alpha-diversity indices and bacterial taxa. The GLR models showed that tin correlated negatively with the Shannon index (β = -0.55, 95% conficence interval [CI]: -0.79, -0.30, PFDR< 0.001) and positively with the Simpson index (β = 0.26, 95% CI: 0.13, 0.39, PFDR< 0.001). The BKMR analysis yielded similar results, showing that tin had the largest posterior inclusion probability for both the Shannon (0.986) and the Simpson (0.796) indices. Tin, cadmium, mercury, lead, and thallium were associated with changes in one or more taxa at the genus level. The BKMR analysis also revealed a negative correlation between metal mixtures and Clostridium_sensu_stricto, and tin contibuted mostly to the negative correlation. Early postnatal exposure to metals were associated with differences in the microbiome among infants admitted to the NICU. However, as the study was cross-sectional, these relationships must be confirmed in further studies.

Sex-specific associations of a ferroalloy metal mixture with motor function in Italian adolescents

Background

Motor function is critical for children's health, yet remains an understudied neurodevelopmental domain. Exposure to metals has been linked with motor function, but no study has examined the joint effects of metal mixtures.

Methods

We evaluated cross-sectional associations between a metal mixture and motor function among 569 adolescents (10-14 years old) living near the ferroalloy industry. Concentrations of blood lead, hair manganese, hair copper, and hair chromium were quantified using inductively coupled plasma mass spectrometry. Neuropsychologists administered multiple fine motor function assessments: pursuit aiming, finger tapping, visual reaction time (VRT), and subtests from the Luria Nebraska battery. We estimated associations between motor function and the metal mixture using quantile-based g-computation and multivariable linear regression, adjusting for child age, sex, and socioeconomic status. We explored sex-specific associations in stratified models.

Results

Associations between the metal mixture and motor function were mostly null but were modified by sex. We observed a beneficial association among females: a quartile increase in all metals in the mixture was associated with a 2.6% faster average response time on the VRT (95% confidence interval [CI] = -4.7%, -0.5%), driven by Cu and Cr. In contrast, this association was adverse among males (ß = 1.5% slower response time [95% CI = -0.7%, 3.9%]), driven by Cu and Mn.

Conclusions

Results suggest that males may be more susceptible to the adverse effects of metal exposure on motor function during adolescence than females. Future studies, particularly prospective study designs, are warranted to further understand the associations of metal mixtures with motor function.

Efficacy, safety, and tolerability of adjunctive Lacosamide therapy for focal seizures in young children aged ≥1 month to ≤4 years: A real-world study

AIMS

To evaluate the efficacy, safety, and tolerability of adjunctive lacosamide therapy against focal seizures in young children (1 month - 4 years).

METHODS

This non-randomized, open-label, and self-controlled real-world study included 105 children (1 month-4 years) with focal seizures treated with adjunctive lacosamide therapy at Children's Hospital of Chongqing Medical University.

RESULTS

(1) The 50% response rates at 3, 6, 9, and 12 months of follow-up were 58.1%, 61.0%, 57.1%, and 56.2%, while the seizure-free rates were 27.6%, 34.3%, 32.4%, and 37.1%, respectively. The 50% response rate of the first addition of lacosamide for focal seizures was much higher than the second and later added treatment at 3 months (p = 0.038). After 1 year of follow-up, these children showed an improvement in neurodevelopmental levels (p < 0.05). (2) Lacosamide retention rate was 72.7% (64/88) after 1 year of follow-up. Lack of efficacy and serious adverse events were independent risk factors for the lacosamide retention rate. (3) During adjunctive lacosamide therapy, 13 (12.4%) patients reported adverse events and five (4.7%) patients withdrew due to adverse events, including vomiting drowsiness, ataxia (0.94%), neck itching with eczema (0.94%), irritability (1.88%), and gastrointestinal discomfort (0.94%).

CONCLUSION

Adjunctive lacosamide therapy was effective, safe, and well-tolerated in young Chinese children with focal seizures in this study.

Phenotypic characteristics and rehabilitation effect of children with regressive autism spectrum disorder: a prospective cohort study

BACKGROUND

In this prospective cohort study, we determined the phenotypic characteristics of children with regressive autism spectrum disorder (ASD) and explored the effects of rehabilitation.

METHODS

We recruited 370 children with ASD aged 1.5-7 years. Based on the Regression Supplement Form, the children were assigned to two groups: regressive and non-regressive. The core symptoms and neurodevelopmental levels of ASD were assessed before and after 1 year of behavioral intervention using the Autism Diagnostic Observation Schedule (ADOS), Social Response Scale (SRS), Children Autism Rating Scale (CARS), and Gesell Developmental Scale (GDS).

RESULTS

Among the 370 children with ASD, 28.38% (105/370) experienced regression. Regression was primarily observed in social communication and language skills. Children with regressive ASD exhibited higher SRS and CARS scores and lower GDS scores than those with non-regressive ASD. After 1 year of behavioral intervention, the symptom scale scores significantly decreased for all children with ASD; however, a lesser degree of improvement was observed in children with regressive ASD than in those with non-regressive ASD. In addition, the symptom scores of children with regressive ASD below 4 years old significantly decreased, whereas the scores of those over 4 years old did not significantly improve. Children with regressive ASD showed higher core symptom scores and lower neurodevelopmental levels. Nevertheless, after behavioral intervention, some symptoms exhibited significant improvements in children with regressive ASD under 4 years of age.

CONCLUSION

Early intervention should be considered for children with ASD, particularly for those with regressive ASD.

Prenatal endocrine-disrupting chemicals exposure and impact on offspring neurodevelopment: A systematic review and meta-analysis

PURPOSE

Considering that endocrine disruptors have certain effects on fetal growth, we conducted a systematic review of epidemiological literature to elucidate the correlation between exposure to endocrine-disrupting chemicals during pregnancy and the neurodevelopment of offspring.

METHOD

We systematically explored PubMed, Web of Science, and CINAHL databases from inception to April 4, 2023. References from pertinent studies were reviewed, and data regarding the link between maternal prenatal EDC exposure and offspring neurological development were compiled. A domain-based approach was used to evaluate studies of neurodevelopmental effects in children ≤3 years old by two reviewers, including cognition, motor, behavior, language, and non-verbal ability.

RESULTS

A comprehensive search yielded 45,373 articles, from which 48 articles, involving 26,005 mother-child pairs, met the criteria and were subsequently included in our analysis. The results revealed that EDC exposure during pregnancy had a significant impact on offspring neurobehavior development, especially in cognition, motor, and language. Our findings indicated adverse associations between prenatal exposure to metals and offspring cognition (before 12 months: β coefficient: -0.28; 95 % CI, -0.50 to -0.06; 1-3 years old: β coefficient: -0.55; 95 % CI: -1.08 to -0.02). Furthermore, metals (β coefficient: -0.71; 95 % CI: -1.23 to -0.19) and phthalates (β coefficient: -0.69; 95 % CI: -1.05 to -0.33) exposure exhibited detrimental effects on motor development from1-3 years old, while poly-fluoroalkyl substances were linked to the disruption of offspring language development (β coefficient: -1.01; 95 % CI: -1.90 to -0.11) within this timeframe. Additionally, exposure to EDCs during pregnancy had a negative impact on cognition development among girls from 12 to 36 months of age (β coefficient: -0.53; 95 % CI: -1.01 to -0.06).

CONCLUSION

Prenatal exposure to EDCs, especially metals, phthalates and, poly-fluoroalkyl substances, was associated with disrupting the development of offspring neurobehavior in the short and long term. Additionally, cognitive development showed gender differences due to prenatal endocrine-disrupting chemicals exposure.

Gestational glyphosate exposure and early childhood neurodevelopment in a Puerto Rico birth cohort

INTRODUCTION

N-(phosphonomethyl)glycine, or glyphosate, is a non-selective systemic herbicide widely used in agricultural, industrial, and residential settings since 1974. Glyphosate exposure has been inconsistently linked to neurotoxicity in animals, and studies of effects of gestational exposure among humans are scarce. In this study we investigated relationships between prenatal urinary glyphosate analytes and early childhood neurodevelopment.

METHODS

Mother-child pairs from the PROTECT-CRECE birth cohort in Puerto Rico with measures for both maternal urinary glyphosate analytes and child neurodevelopment were included for analysis (n = 143). Spot urine samples were collected 1-3 times throughout pregnancy and analyzed for glyphosate and aminomethylphosphonic acid (AMPA), an environmental degradant of glyphosate. Child neurodevelopment was assessed at 6, 12, and 24 months using the Battelle Developmental Inventory, 2nd edition Spanish (BDI-2), which provides scores for adaptive, personal-social, communication, motor, and cognitive domains. We used multivariable linear regression to examine associations between the geometric mean of maternal urinary glyphosate analytes across pregnancy and BDI-2 scores at each follow-up. Results were expressed as percent change in BDI-2 score per interquartile range increase in exposure.

RESULTS

Prenatal AMPA concentrations were negatively associated with communication domain at 12 months (%change = -5.32; 95%CI: 9.04, -1.61; p = 0.007), and communication subdomain scores at 12 and 24 months. At 24 months, four BDI-2 domains were associated with AMPA: adaptive (%change = -3.15; 95%CI: 6.05, -0.25; p = 0.038), personal-social (%change = -4.37; 95%CI: 7.48, -1.26; p = 0.008), communication (%change = -7.00; 95%CI: 11.75, -2.26; p = 0.005), and cognitive (%change = -4.02; 95%CI: 6.72, -1.32; p = 0.005). Similar trends were observed with GLY concentrations, but most confidence intervals include zero. We found no significant associations at 6 months.

CONCLUSIONS

Our results suggest that gestational exposure to glyphosate is associated with adverse early neurodevelopment, with more pronounced delays at 24 months. Given glyphosate's wide usage, further investigation into the impact of gestational glyphosate exposure on neurodevelopment is warranted.

Prenatal exposure to metal mixtures and childhood temporal processing in the PROGRESS Birth Cohort Study: Modification by childhood obesity

Children are frequently exposed to various biological trace metals, some essential for their development, while others can be potent neurotoxicants. Furthermore, the inflammatory and metabolic conditions associated with obesity may interact with and amplify the impact of metal exposure on neurodevelopment. However, few studies have assessed the potential modification effect of body mass index (BMI). As a result, we investigated the role of child BMI phenotype on the relationship between prenatal exposure to metal mixtures and temporal processing. Leveraging the PROGRESS birth cohort in Mexico City, children (N = 563) aged 6-9 years completed a Temporal Response Differentiation (TRD) task where they had to hold a lever down for 10-14 s. Blood and urinary metal (As, Pb, Cd, and Mn) measurements were collected from mothers in the 2nd and 3rd trimesters. Child BMI z-scores were dichotomized to normal (between -2 and +0.99) and high (≥1.00). Covariate-adjusted weighted quantile sum (WQS) regression models were used to estimate and examine the combined effect of metal biomarkers (i.e., blood and urine) on TRD measures. Effect modification by the child's BMI was evaluated using 2-way interaction terms. Children with a high BMI and greater exposure to the metal mixture during prenatal development exhibited significant temporal processing deficits compared to children with a normal BMI. Notably, children with increased exposure to the metal mixture and higher BMI had a decrease in the percent of tasks completed (β = -10.13; 95 % CI: -19.84, -0.42), number of average holds (β = -2.15; 95 % CI: -3.88, -0.41), longer latency (β = 0.78; 95 % CI: 0.13, 1.44), and greater variability in the standard deviation of the total hold time (β = 2.08; 95 % CI: 0.34, 3.82) compared to normal BMI children. These findings implicate that high BMI may amplify the effect of metals on children's temporal processing. Understanding the relationship between metal exposures, temporal processing, and childhood obesity can provide valuable insights for developing targeted environmental interventions.

Assessment of sources and health risks of heavy metals in metropolitan household dust among preschool children: The LEAPP-HIT study

The most common construction material used in Taiwan is concrete, potentially contaminated by geologic heavy metals (HMs). Younger children spend much time indoors, increasing HM exposure risks from household dust owing to their behaviors. We evaluated arsenic (As), cadmium (Cd), and lead (Pb) concentrations in fingernails among 280 preschoolers between 2017 and 2023. We also analyzed HM concentrations, including As, Cd, Pb, chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), iron (Fe), and manganese (Mn), in 90 household dust and 50 road dust samples from a residential area where children lived between 2019 and 2021 to deepen the understanding of sources and health risks of exposure to HMs from household dust. The average As, Cd, and Pb concentrations in fingernails were 0.12 ± 0.06, 0.05 ± 0.05, and 0.95 ± 0.77 μg/g, respectively. Soil parent materials, indoor construction activities, vehicle emissions, and mixed indoor combustion were the pollution sources of HMs in household dust. Higher Cr and Pb levels in household dust may pose non-carcinogenic risks to preschoolers. Addressing indoor construction and soil parent materials sources is vital for children's health. The finding of the present survey can be used for indoor environmental management to reduce the risks of HM exposure and avoid potential adverse health effects for younger children.

Urinary biomarkers of exposure to toxic and essential elements: A comparison of infants fed with human milk or formula

Background

Early-life exposure to nonessential (toxic) and essential trace elements can influence child development. Although infant formula powders and the water used to reconstitute them can contain higher concentrations of many elements compared with human milk, the influence of feeding mode on reliable biomarkers of infant exposure has rarely been demonstrated.

Methods

We evaluated associations between urinary biomarkers and feeding mode (exclusively human milk, exclusively formula, or combination-fed) for four toxic (arsenic, cadmium, nickel, and uranium) and three essential elements (cobalt, molybdenum, and selenium) using general linear models.

Results

A total of 462 participants from the rural New Hampshire Birth Cohort Study were on average 6 weeks old between July 2012 and March 2019 and had urine samples, 3-day food diaries, and relevant covariate data available. In adjusted models, urinary arsenic was 5.15 (95% confidence interval = 4.04, 6.58), molybdenum was 19.02 (14.13-25.59), and selenium was 1.51 (1.35-1.68) times higher in infants fed exclusively with formula compared with infants fed exclusively with human milk. By contrast, urinary uranium was 0.59 (0.46-0.75) and cobalt was 0.78 (0.65-0.95) times lower with formula feeding than human milk feeding.

Conclusion

Our findings suggest that infant exposure to several potentially toxic elements varies by feeding mode, as concentrations of reliable urinary biomarkers were higher with formula or human milk, depending on the element. Importantly, exposure to arsenic increased with household tap water arsenic regardless of feeding mode, suggesting that all infants could be at risk in populations with high concentrations of arsenic in drinking water.

Associations between a metal mixture and infant negative affectivity: Effect modification by prenatal cortisol and infant sex

In-utero exposures interact in complex ways that influence neurodevelopment. Animal research demonstrates that fetal sex moderates the impact of joint exposure to metals and prenatal stress measures, including cortisol, on offspring socioemotional outcomes. Further research is needed in humans. We evaluated the joint association of prenatal exposures to a metal mixture and cortisol with infant negative affectivity, considering sex differences. Analyses included 226 (29% White, Non-Hispanic) mother-infant pairs with data on exposures and negative affectivity assessed using the Infant Behavior Questionnaire-Revised in 6-month-olds. Results showed that girls whose mothers had higher cortisol had significantly higher scores of Fear and Sadness with greater exposure to the mixture. Examining higher-order interactions may better elucidate the effects of prenatal exposure to metals and cortisol on socioemotional functioning.

Prenatal prevalence and postnatal manifestations of 16p11.2 deletions: A new insights into neurodevelopmental disorders based on clinical investigations combined with multi-omics analysis

BACKGROUND

The 16p11.2 deletion is one of the most common genetic aetiologies of neurodevelopmental disorders (NDDs). The prenatal phenotype of 16p11.2 deletion and the potential mechanism associated with postnatal clinical manifestations were largely unknow. We revealed the developmental trajectories of 16p11.2 deletion from the prenatal to postnatal periods and to identify key signaling pathways and candidate genes contributing to neurodevelopmental abnormalities.

METHODS

In this 5-y retrospective cohort study, women with singleton pregnancies who underwent amniocentesis for chromosomal abnormalities were included. Test of copy-number variations (CNVs) involved single nucleotide polymorphism-array and CNV-seq was performed to detected 16p11.2 deletion. For infants born carrying the 16p11.2 deletion, neurological and intellectual evaluations using the Chinese version of the Gesell Development Scale. For patients observed to have vertebral malformations, Sanger sequencing for T-C-A haplotype of TBX6 was performed. For those infants with clinical manifestations, whole-exome sequencing was consecutively performed in trios to rule out single-gene diseases, and transcriptomics combined with untargeted metabolomics were performed.

RESULTS

The prevalence of 16p11.2 deletion was 0.063% (55/86,035) in the prenatal period. Up to 80% (20/25) of the 16p11.2 deletions were proven de novo by parental confirmation. Approximately half of 16p11.2 deletions (28/55) were detected with prenatal abnormal ultrasound findings. Vertebral malformations were identified as the most distinctive structural malformations and were enriched in fetuses with 16p11.2 deletions compared with controls (90.9‰ [5/55] vs. 8.4‰ [72/85,980]; P < 0.001). All 5 fetuses with vertebral malformations were confirmed to have the TBX6 haplotype of T-C-A. Overall, 47.6% (10/21) infants birthed were diagnosed with NDDs of different degrees. Language impairment was the predominant manifestation (7/10; 70.0%), followed by motor delay (5/10; 50%). Multi-omics analysis indicated that MAPK3 was the central hub of the differentially expressed gene (DEG) network. We firstly reported that histidine-associated metabolism may be the core metabolic pathway related to the 16p11.2 deletion.

CONCLUSION

We demonstrated the prenatal presentation, incomplete penetrance and variable expressivity of the 16p11.2 deletion. We identified vertebral malformations were the most distinctive prenatal phenotypes, and language impairment was the predominant postnatal manifestation. Most of the 16p11.2 deletion was de novo. Meanwhile, we suggested that MAPK3 and histidine-associated metabolism may contribute to neurodevelopmental abnormalities of 16p11.2 deletion.

Association of Gestational Diabetes Mellitus Complicated With Short Sleep Duration and Child Neurodevelopmental Delay

CONTEXT

Gestational diabetes mellitus (GDM) is a risk factor for child neurodevelopmental delay. Maternal short sleep duration (SSD) may aggravate glucose metabolism disorder in women with GDM. However, it is unclear whether maternal SSD will further affect the neurodevelopmental outcomes of children.

OBJECTIVE

To identify the association of GDM complicated with SSD and child neurodevelopmental delay.

METHODS

This prospective study included 7069 mother-child pairs. Between 24 and 28 weeks of gestation, GDM was based on the 75-g oral-glucose-tolerance test. Self-reported sleep duration was collected via the Pittsburgh Sleep Quality Index questionnaire in the second (24-28 weeks) and third (32-36 weeks) trimesters. Outcomes of neurodevelopmental delay in 6 to 36 months postpartum were evaluated using Denver Developmental Screening Test-II and Gesell Development Diagnosis Scale.

RESULTS

Compared with the unexposed group, women with "GDM + SSD" have the greatest risks of child neurodevelopmental delay (hazard ratio with 95% CI: 1.58 [1.03-2.44]). "GDM + SSD" was associated with the greatest risks of maternal-fetal glucose metabolic disorder. An interquartile ratio (0.58 mmol/L) increase in cord blood C-peptide was associated with the risk of child neurodevelopmental delay (hazard ratio with 95% CI: 1.28 [1.12-1.48]). The stronger linear association of maternal glucose metabolism profiles and C-peptide in women with "GDM + SSD" was also demonstrated. The proportion of association between "GDM + SSD" and child neurodevelopmental delay mediated by C-peptide was 14.4%.

CONCLUSION

GDM complicated with SSD was associated with increased risk for child neurodevelopmental delay by enhancing the intergenerational association of maternal-fetal glucose metabolism disorder.

Exposure to metal mixtures and young children's growth and development: A biomonitoring-based study in Eastern China

Exposure to metal mixtures may affect children's health but the conclusions are controversial. We aimed to investigate the associations of metal mixture exposure with children's physical and behavioral development. 15 metals were detected in the urine samples of 278 preschoolers aged 3-6 years from eastern China. Multiple linear models and restricted cubic splines were used to evaluate dose-response relationships between single metal and children's physical and behavioral development. The Bayesian Kernel Machine Regression (BKMR) models, the weighted quantile sum (WQS) models and Quantile G-Computation were applied to evaluate the joint effects of metal mixtures. The results showed that arsenic (As) was negatively associated with z score of height for age (HAZ) in individual-metal models [β (95%CI): - 0.22 (-0.38, -0.06), P = 0.006]. Concerning children's behavioral development, multiple-metal models demonstrated a negative association with strontium (Sr) [β (95%CI): - 0.82 (-1.38, -0.26), P = 0.004], and a positive association with tin (Sn) [β (95%CI): 0.69 (0.16, 1.21), P = 0.010]. Notably, these associations remained significant or suggestive even after adjustments for multiple tests, sensitivity analyses, and application of different statistical models, including BKMR, WQS, and Quantile G-Computation. Furthermore, the study identified a negative joint effect of the metal mixture on HAZ, as demonstrated by BKMR and Quantile G-Computation models, with As playing an irreplaceable role in this observed impact. In summary, exposure to As appears to have adverse effects on HAZ, while exposure to Sn may hinder children's behavioral development. Conversely, exposure to Sr may have a protective effect on children's behavioral development. Additionally, the combined impact of metal mixtures is implicated in potentially impairing children's physical development, particularly in terms of HAZ.

Association of co-exposure to metal(loid)s during pregnancy with birth outcomes in the Tibetan plateau

Maternal metal (loid)s exposure has been related to birth outcomes but the results are still inconclusive. Most previous studies have discussed the single metal (loid)s, neglecting the scene of co-exposure. We examined the associations of both single metal (loid)s and metal mixtures with birth outcomes in a birth cohort from the Tibetan Plateau, including body weight, body length, head circumference, small for gestational age (SGA), and Ponderal index (PI). In our analysis of 1069 women, we measured 29 metal (loid)s in urine samples in the third trimester. The associations of single metal (loid)s with categorical or continuous birth outcomes were evaluated using a generalized linear mixed-effects model or linear mixed-effects model, respectively. The least absolute shrinkage and selection operator, Bayesian kernel machine, and Quantile g-computation regression were used to explore the joint association. We also evaluated the interactive effects of ethnicity and altitude on the effect of metal (loid)s on birth outcomes. Copper (Cu) concentration in maternal urine was positively associated with SGA, birth weight, birth length, and head circumference in the single pollutant models. For instance, Cu was associated with an increased risk of SGA [OR (95% CI) = 1.56 (1.23, 1.97); P < 0.001]. We didn't find significant joint association of metal mixtures with birth outcomes except a positive association between the mixture of Cu, Magnesium (Mg), and Iron (Fe) with the risk of SGA when the exposure level was above its 80th percentile, and Cu dominated the adverse association in a non-linear manner. Living altitude modified the associations of Cu with SGA and the positive association was only found in participants living at high altitude. In conclusion, maternal urinary metal (loid)s, especially Cu, was the dominant harmful metal (loid)s when associated with SGA on the Tibetan Plateau.

Maternal urinary metal(loid)s and risk of preterm birth: A cohort study in the Tibetan Plateau

Maternal metal(loid)s exposure has been related to preterm birth (PTB), but the results are still inconclusive. Previous studies have mainly discussed the harmful metal(loid)s, neglecting beneficial ones. We examined the association of maternal metal(loid)s with PTB and gestational age (GA) in a birth cohort from the Tibetan Plateau. We measured 29 metal(loid)s in urine samples from 1081 pregnant women in the third trimester. Information regarding demographics, socioeconomic status, diet, medication, and lifestyle was collected through standardized interviews. The associations of single metal(loid)s with PTB or GA were evaluated using a generalized linear mixed-effects model or linear mixed-effects model. Elastic net and Bayesian kernel machine regressions were used to explore the joint associations. Magnesium (Mg), Copper (Cu), and Tin (Sn) were the main "harmful" metal(loid)s positively and negatively associated with PTB or GA, respectively. Mg was the dominant "harmful" metal(loid)s associated with PTB in a J-shape. A one-fold increase in Mg was associated with a 38% increased risk of PTB [OR (95% CI) = 1.38 (1.15, 1.65), PFDR＜0.05] and 0.17 weeks shortening of GA [β (95% CI) = -0.25 (-0.35, -0.14), PFDR＜0.05]. Cesium (Cs), rubidium (Rb), and Molybdenum (Mo) were the main "beneficial" metals. Cs dominated the "beneficial" associations and was negatively associated with PTB in a linear manner. A one-fold increase in Cs was associated with a 67% decreased risk of PTB [OR (95% CI) = 0.43 (0.27, 0.67), PFDR＜0.05] and 0.24 weeks of prolonged GA [β (95% CI) = 0.35 (0.13, 0.56), PFDR＜0.05]. Ethnicity and living altitude modified the association of Mg and Cu with PTB or GA. In conclusion, Maternal urinary metal(loid)s were bi-directionally associated with PTB in a population in the Tibetan Plateau. Mg and Cs were the dominant "harmful" and "beneficial" metal(loid)s, respectively.

Clinical and genetic characteristics of 36 children with Joubert syndrome

Background and aims

Joubert syndrome (JBTS, OMIM # 213300) is a group of ciliopathies characterized by mid-hindbrain malformation, developmental delay, hypotonia, oculomotor apraxia, and breathing abnormalities. Molar tooth sign in brain imaging is the hallmark for diagnosing JBTS. It is a clinically and genetically heterogeneous disorder involving mutations in more than 40 ciliopathy-related genes. However, long-term follow-up data are scarce, and further research is needed to determine the abundant phenotypes and genetics of this disorder. The study aimed to summarize clinical manifestations, particular appearance on cranial imaging, genetic data, and prognostic features of patients with JBTS.

Methods

A retrospective case review of 36 cases of JBTS from May 1986 to December 2021 was performed. Clinical data of JBTS patients with development retardation and molar tooth sign on cranial imaging as the main features were analyzed. Genetic testing was performed according to consent obtained from patients and their families. The Gesell Developmental Scale was used to evaluate the intelligence level before and after treatment. The children were divided into a purely neurological JBTS (pure JBTS) group and JBTS with multi-organ system involvement group and then followed up every 3-6 months.

Results

We enrolled 18 males and 18 females. Thirty-four (94.44%) cases had developmental delay, one patient (2.78%) had strabismus, and one patient (2.78%) had intermittent dizziness. There was one case co-morbid with Lesch-Nyhan syndrome. Three-quarters of cases had one or more other organ or system involvement, with a greater predilection for vision and hearing impairment. JBTS could also involve the skin. Thirty-one cases (86.11%) showed a typical molar tooth sign, and five cases showed a bat wing sign on cranial imaging. Abnormal video electroencephalogram (VEEG) result was obtained in 7.69% of cases. We found six JBTS-related novel gene loci variants: CPLANE1: c.4189 + 1G > A, c.3101T > C(p.Ile1034Thr), c.3733T > C (p.Cys1245Arg), c.4080G > A(p.Lys1360=); RPGRIP1l: c.1351-11A > G; CEP120: c.214 C > T(p.Arg72Cys). The CHD7 gene may be potentially related to the occurrence of JBTS. Analysis showed that the prognosis of pure JBTS was better than that of JBTS with neurological and non-neurological involvement after the formal rehabilitation treatment (P < 0.05). Of the three children with seizures, two cases had epilepsy with a poor prognosis, and another case had breath-holding spells.

Conclusion

Our findings indicate that early cranial imaging is helpful for the etiological diagnosis of children with unexplained developmental delay and multiple malformations. Patients with JBTS may have coexisting skin abnormalities. The novel gene loci of CPLANE1, RPGRIP1l, and CEP120 were associated with JBTS in our study and provided significant information to enrich the related genetic data. Future works investigating several aspects of the association between CHD7 gene and JBTS merit further investigation. The prognosis of children with pure JBTS is better than that of children with JBTS with non-neurological involvement.

Advances in Genetics and Epigenetics of Developmental Coordination Disorder in Children

Developmental coordination disorder (DCD) is a developmental disorder characterized by impaired motor coordination, often co-occurring with attention deficit disorder, autism spectrum disorders, and other psychological and behavioural conditions. The aetiology of DCD is believed to involve brain changes and environmental factors, with genetics also playing a role in its pathogenesis. Recent research has identified several candidate genes and genetic factors associated with motor impairment, including deletions, copy number variations, single nucleotide polymorphisms, and epigenetic modifications. This review provides an overview of the current knowledge in genetic research on DCD, highlighting the importance of continued research into the underlying genetic mechanisms. While evidence suggests a genetic contribution to DCD, the evidence is still in its early stages, and much of the current evidence is based on studies of co-occurring conditions. Further research to better understand the genetic basis of DCD could have important implications for diagnosis, treatment, and our understanding of the condition's aetiology.

Association of polycyclic aromatic hydrocarbons exposure with child neurodevelopment and adult emotional disorders: A meta-analysis study

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) have been demonstrated to be neurotoxic.

OBJECTIVES

To summarize the existing epidemiological studies to quantify the effects of PAHs exposure on child neurodevelopment and adult emotional disorders.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

We conducted a systematic literature search for studies of child neurodevelopment and adult emotional disorders published in English up to April 2022 in the databases of PubMed, Web of Science and Embase using combinations of MeSH terms and Entry terms, and the articles were filtered out according to data availability. A variety of common PAHs were included in the meta-analysis: 1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 3-hydroxyfluorene, 9-hydroxyfluorene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 3-hydroxyphenanthrene, 4-hydroxyphenanthrene, 9-hydroxyphenanthrene, 1-hydroxypyrene and benzoapyrene (BaP).

STUDY EVALUATION AND SYNTHESIS METHODS

We extracted the content of each article, summarized its design characteristics and performed quality evaluation. We combined the odds ratio (OR) available in various studies to obtain the risk of PAHs exposure and adaptive, language, social, attention, motor skills and child depression/anxiety in children ≤ 15 years old. In addition, we also conducted a meta-analysis on the relationship between PAHs exposure and the risk of depression in adults.

RESULTS

We included a total of 16 epidemiological studies (4 cross-sectional studies and 12 cohort studies). The sample size of all included studies ranged from 110 to 9625. Prenatal exposure to PAHs was found to be associated with increased risk of social behavior (OR = 1.60, 95% CI: 1.00-2.54), attention (OR = 2.99, 95% CI: 1.48-6.02), motor skill problems (OR = 1.91, 95% CI: 1.27-2.86) and any adverse neurodevelopmental outcome in children (OR = 2.10, 95% CI: 1.69-2.62). In addition, we found that PAHs exposure could increase the risk of adult depression, with 2-hydroxyfluorene exposure showing the highest combined OR (OR = 1.48, 95% CI: 1.10-2.00).

CONCLUSIONS

The results suggested that PAHs exposure are associated with increased risk of child neurodevelopment and adult depression. The neurotoxic effects of PAHs exposure in human being should be paid more attention. The results suggested that PAHs exposure are associated with increased risk of child neurodevelopment and adult depression. The neurotoxic effects of PAHs exposure in human being should be paid more attention. Steps should be taken to enhance the biomonitoring of PAHs and to reduce the exposure in general population.

Interrelation between homocysteine metabolism and the development of autism spectrum disorder in children

Evidence is emerging that dysregulation of circulating concentrations of homocysteine, an important intermediate in folate and vitamin B12 metabolism, is associated with autism spectrum disorder (ASD), but comprehensive assessments and correlations with disease characteristics have not been reported. Multivariate ordinal regression and restricted cubic spline (RCS) models were used to estimate independent correlations between serum homocysteine, folate, and vitamin B12 levels and clinical outcomes and severity of children with ASD. After adjusting for confounding factors, serum homocysteine levels were significantly higher in children with ASD than in healthy controls (β: 0.370; 95% CI: 0.299~0.441, p < 0.001). Moreover, homocysteine had a good diagnostic ability for distinguishing children with ASD from healthy subjects (AUC: 0.899, p < 0.001). The RCS model indicated a positive and linear association between serum homocysteine and the risk of ASD. The lowest quartile of folate was positively associated with ASD severity (OR: 4.227, 95% CI: 1.022~17.488, p = 0.041) compared to the highest quartile, and serum folate showed a negative and linear association with ASD severity. In addition, decreased concentrations of folate and vitamin B12 were associated with poor adaptive behavior developmental quotients of the Gesell Developmental Schedules (p < 0.05). Overall, an increased homocysteine level was associated with ASD in a linear manner and is thus a novel diagnostic biomarker for ASD. Decreased concentrations of folate and vitamin B12 were associated with poor clinical profiles of children with ASD. These findings suggest that homocysteine-lowering interventions or folate and vitamin B12 supplementation might be a viable treatment strategy for ASD.