Prenatal exposure to per- and polyfluoroalkyl substances, fetal thyroid function, and intelligence quotient at 7 years of age: Findings from the Sheyang Mini Birth Cohort Study.

BACKGROUND: Prenatal exposure to per- and polyfluoroalkyl substances (PFASs) influences neurodevelopment. Thyroid homeostasis disruption is thought to be a possible underlying mechanism. However, current epidemiological evidence remains inconclusive. OBJECTIVES: This study aimed to explore the effects of prenatal PFAS exposure on the intelligence quotient (IQ) of school-aged children and assess the potential mediating role of fetal thyroid function. METHODS: The study included 327 7-year-old children from the Sheyang Mini Birth Cohort Study (SMBCS). Cord serum samples were analyzed for 12 PFAS concentrations and 5 thyroid hormone (TH) levels. IQ was assessed using the Wechsler Intelligence Scale for Children-Chinese Revised (WISC-CR). Generalized linear models (GLM) and Bayesian Kernel Machine Regression (BKMR) were used to evaluate the individual and combined effects of prenatal PFAS exposure on IQ. Additionally, the impact on fetal thyroid function was examined using a GLM, and a mediation analysis was conducted to explore the potential mediating roles of this function. RESULTS: The molar sum concentration of perfluorinated carboxylic acids (ΣPFCA) in cord serum was significantly negatively associated with the performance IQ (PIQ) of 7-year-old children (ß = -6.21, 95 % confidence interval [CI]: -12.21, -0.21), with more pronounced associations observed among girls (ß = -9.57, 95 % CI: -18.33, -0.81) than in boys. Negative, albeit non-significant, cumulative effects were noted when considering PFAS mixture exposure. Prenatal exposure to perfluorooctanoic acid, perfluorononanoic acid, and perfluorooctanesulfonic acid was positively associated with the total thyroxine/triiodothyronine ratio. However, no evidence supported the mediating role of thyroid function in the link between PFAS exposure and IQ. CONCLUSIONS: Increased prenatal exposure to PFASs negatively affected the IQ of school-aged children, whereas fetal thyroid function did not serve as a mediator in this relationship.

Simultaneous determination of twelve neonicotinoids and six metabolites in human urine with isotope-dilution UPLC-Q-Orbitrap HRMS.

The extensive global use of neonicotinoid insecticides (NNIs) has led to widespread human exposure, necessitating the development of effective methods for large-scale biomonitoring. However, current methods are inadequate in simultaneously and accurately detecting various NNIs or their metabolites (m-NNIs). In this study, we aimed to establish a robust method using solid-phase extraction (SPE)-ultra high performance liquid chromatography tandem Q-Orbitrap high resolution mass spectrometry (UPLC-Q-Orbitrap HRMS) for the simultaneous determination of 12 NNIs and 6 m-NNIs in human urine. Samples were prepared using Oasis HLB 96 well plate with Isopropanol: methanol (7:3, v/v) as the elution solvent. The target compounds were separated using the Accucore RP-MS column and subsequently analyzed under parallel reaction monitoring mode. NTN32692 (m/z = 255.06433) was confirmed to be the specific metabolite of cycloxaprid for the further detection. Satisfactory recoveries (81.6-122.4 %) of the NNIs and m-NNIs were observed, with intra- (n = 3) and inter-day (n = 9) relative standard deviation (RSD) ranging from 0.8 % to 13.7 % and from 1.1 % to 18.6 %, respectively. Good linearity (R2 > 0.99) was achieved for all analytes. The limits of detection (LODs) for all target analytes ranged from 0.01 ng/mL to 0.65 ng/mL. This method was applied to urine samples collected from 10 children recruited from an agricultural area in China. Our study provides an effective method to identify and assess human exposure to NNIs and their metabolites.

Sex-specific associations of maternal and childhood urinary arsenic levels with emotional problems among 6-year-age children: Evidence from a longitudinal cohort study in China.

BACKGROUND: Arsenic exposure has been linked to neurobehavior development disorders among children in cross-sectional studies, but there is little information on the effects of prenatal and childhood arsenic exposure on childhood behavior problem, especially emotional problems. OBJECTIVE: To explore the relationship between prenatal and childhood arsenic exposure and behavior problems among six-year-old children. METHODS: 389 mother-child pairs from a longitudinal birth cohort were enrolled in the study. The concentrations of arsenic in maternal and 6-year-old children's urine were measured using inductively coupled plasma mass spectrometry (ICP-MS). Neurobehavioral development in 6-year-old children was assessed by Child Behavior Checklist (CBCL). Generalized linear regression models were used to relate arsenic exposure to the score of different domains in CBCL. RESULTS: The median concentrations of maternal and 6-year-old children's urinary arsenic were 22.22 and 33.86 µg/L, respectively. After adjusting for potential covariates, natural logarithm transformed concurrent urinary arsenic levels were significantly associated with scores of anxious and depressed problems in 6-year-old girls (ß = 0.71, 95% CI: 0.12-1.31, p = 0.018). Furthermore, in terms of the trajectory of arsenic exposure, compared with the "consistently low" group, the "low to high" group (ß = 2.73, 95% CI: -3.99 to 9.45, p = 0.425) had a greater effect on total score of CBCL than "high to low" group (ß = -0.93, 95% CI: -7.22 to 5.36, p = 0.771) in girls, although insignificant. CONCLUSIONS: Our results suggested that concurrent arsenic exposure might have an adverse effect of emotional status in girls. Further studies are needed to verify the findings and explore the mechanisms of the sex-specific association.

Per- and polyfluoroalkyl substances in umbilical cord serum and body mass index trajectories from birth to age 10 years: Findings from a longitudinal birth cohort (SMBCS).

BACKGROUND: Prenatal exposure to per- and polyfluoroalkyl substances (PFAS) has been linked to low birth weight but higher childhood weight and obesity. However, little is known regarding the associations between PFAS exposure and dynamic body mass index (BMI) trajectories, particularly from birth through preadolescence. OBJECTIVE: To evaluate the associations of cord serum PFAS concentrations with BMI trajectories from birth to age 10 years and longitudinal BMI in different periods. METHODS: Based on 887 mother-child pairs in the longitudinal prospective birth cohort, we measured 12 PFAS congeners in cord serum and calculated BMI with anthropometric indicators at 9 follow-up time points from birth to age 10 years. The BMI trajectories were identified using group-based trajectory model (GBTM). To estimate the associations of cord serum PFAS levels with BMI trajectories and longitudinal changes in BMI, logistic regression models, linear mixed models, Bayesian kernel machine regression, and quantile-based g-computation models (QGC) were used. RESULTS: The median concentrations of 10 PFAS congeners included in statistical analysis ranged from 0.047 to 3.623 µg/L. Two BMI trajectory classes were identified by GBTM, characterized by high group and low group. In logistic regression models, five PFAS congeners (PFBA, PFHpA, PFHxS, PFHpS, and PFDoDA) were associated with the higher probability of being in high BMI trajectory group (odds ratio, OR: 1.21 to 1.74, p < 0.05). Meanwhile, higher PFAS mixture were related to elevated odds for the high group in both BKMR models and QGC models, with PFHpA and PFHpS being the two most important drivers jointly. In the sex-stratified analysis, the positive associations remained significant exclusively among males. In the longitudinal analysis, PFUnDA and PFDoDA were associated with increased BMI from birth to age 10 years. Furthermore, PFBS and PFHpA were negatively related to BMI throughout infancy and toddlerhood (from birth to age 3 years), whereas PFDoDA confirmed a positive association with mid-childhood (from age 6 to 10 years) BMI. CONCLUSIONS: Prenatal PFAS exposure was positively associated with BMI trajectories from birth to preadolescence and longitudinal BMI in various periods. Future research could use better trajectory modeling strategies to shape more complete growth trajectories and explore the relationship between BMI trajectories and adulthood health.

Associations of perfluoroalkyl substances with adipocytokines in umbilical cord serum: A mixtures approach.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS), a kind of emerging environmental endocrine disruptors, may interfere with the secretion of adipokines and affect fetal metabolic function and intrauterine development. However, the epidemiological evidence is limited and inconsistent. We examined the associations of single and multiple PFAS exposures in utero with adipocytokine concentrations in umbilical cord serum. METHODS: This study included 1111 mother-infant pairs from Sheyang Mini Birth Cohort Study (SMBCS), and quantified 12 PFAS and two adipokine in umbilical cord serum. Generalized linear models (GLMs) and Bayesian Kernel Machine Regression (BKMR) models were applied to estimate the associations of single- and mixed- PFAS exposure with adipokines, respectively. Furthermore, sex-stratification was done in each model to assess the sexually dimorphic effects of PFAS. RESULTS: 10 PFAS were detected with median concentrations (µg/L) ranging from 0.04 to 3.97, (except 2.7% for PFOSA and 1.7% for PFDS, which were excluded). In GLMs, for each doubling increase in PFBS, PFHpA, PFHxS, PFHpS, PFUnDA and PFDoDA, leptin decreased between 14.04% for PFBS and 22.69% for PFHpS (P < 0.05). PFAS, except for PFNA, were positively associated with adiponectin, and for each doubling of PFAS, adiponectin increased between 3.27% for PFBS and 12.28% for PFHxS (P < 0.05). In addition, infant gender modified the associations of PFAS with adipokines, especially the associations of PFBS, PFOA and PFHxS with adiponectin. Similarly, significant associations of PFAS mixtures with leptin and adiponectin were observed in the BKMR models. PFDA, PFOS, PFNA and PFHpS were identified as important contributors. In the sex-stratified analysis of BKMR models, the associations between PFAS mixtures and adipokines were more pronounced in males. CONCLUSIONS: PFAS levels were significantly associated with adipokines in cord serum, suggesting that intrauterine mixture of PFAS exposure may be related to decreased fetal leptin level but increased fetal adiponectin level and the associations may be sex-specific.

Dietary diversity and determinants among left behind children in rural area / 中国学校卫生

Objective@#To evaluate the status of dietary diversity and determinants among school age left behind children.@*Methods@#A total of 501 children aged 9-10 years in Sheyang Mini Cohort Study were enrolled from Sheyang City in Jiangsu Province during 2019. A questionnaires survey was administrated to collect left behind and socioeconomic information. Twenty four hour dietary recall survey was conducted, dietary diversity score (DDS 10 and DDS) and food variety score (FVS) were computed according to Food and Agriculture Organization (FAO). Weight and height of children were measured and sex and age standardized body mass index was used to define obesity. Multivariable regression models were preformed to explore the determinants of dietary diversity in school age left behind children.@*Results@#The proportion of left behind children was 40.9%. The mean value and standard deviation of three kinds of dietary diversity score (DDS 10 , DDS, FVS) in left behind children were (5.69±1.31)(6.55±1.44) and (13.48± 4.23 ), respectively. All of these were lower than that in non left behind children (DDS 10 :5.99±1.29; DDS:6.79±1.40; FVS:14.15±4.22). Significant difference in DDS 10 between left behind and non left behind children was observed ( P =0.01). The results of multivariable regression demonstrated that gender, passive smoking, family education level and family economic status were related to dietary diversity scores ( P <0.05).@*Conclusion@#Dietary diversity in school age left behind children was not optimistic and gender, passive smoking, parental education level, family economic status and left behind situation play a critical role in dietary diversity among these children.