Association of perfluoroalkyl substances with gestational hypertension and preeclampsia in the MIREC study

Per- and polyfluoroalkyl substances in Chinese commercially available red swamp crayfish (Procambarus clarkii): Implications for human exposure and health risk assessment

The extensive utilization of per- and polyfluoroalkyl substances (PFASs) has led to their pervasive presence in the environment, resulting in contamination of aquatic products. Prolonged exposure to PFASs has been linked to direct hepatic and renal damage, along with the induction of oxidative stress, contributing to a spectrum of chronic ailments. Despite the recent surge in popularity of red swamp crayfish as a culinary delicacy in China, studies addressing PFASs' exposure and associated health risks from their consumption remain scarce. To address this gap, our study investigated the PFASs' content in 85 paired edible tissue samples sourced from the five primary red swamp crayfish breeding provinces in China. The health risks associated with dietary exposure were also assessed. Our findings revealed widespread detection of PFASs in crayfish samples, with short-chain perfluoroalkyl carboxylic acids (PFCAs) exhibiting the highest concentrations. Notably, the total PFAS concentration in the hepatopancreas (median: 160 ng/g) significantly exceeded that in muscle tissue (5.95 ng/g), as did the concentration of every single substance. The hazard quotient of perfluorohexanesulfonic acid (PFHxS) via consuming crayfish during peak season exceeded 1. In this case, a potential total non-cancer health risk of PFASs, which is mainly from the hepatopancreas and associated with PFHxS, is also observed (hazard index>1). Thus, it is recommended to avoid consuming the hepatopancreas of red swamp crayfish. Greater attention should be paid to governance technology innovation and regulatory measure strengthening for short-chain PFASs.

Prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and associations with hypertensive disorders of pregnancy in the Atlanta African American Maternal-Child cohort

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that are slow to break down in the environment and widely detected in humans. Epidemiological evidence suggests that prenatal exposure to perfluorooctanoic acid (PFOA), a legacy PFAS, is linked to gestational hypertension and preeclampsia. However, the relationship between other PFAS, which are structurally similar, and these outcomes remains largely understudied, despite biologic plausibility. Here, we examined associations between serum PFAS mixtures in relation to hypertensive disorders of pregnancy within a birth cohort of African Americans.

METHODS

Participants in the present study were enrolled in the Atlanta African American Maternal-Child cohort between 2014 and 2020 (n = 513). Serum samples collected between 8 and 14 weeks gestation were analyzed for four PFAS. Logistic regression was used to assess associations between individual natural log transformed PFAS and specific hypertensive disorders of pregnancy (preeclampsia, gestational hypertension), while quantile g-computation was used to estimate mixture effects. Preeclampsia and gestational hypertension were treated as separate outcomes in individual models. All models were adjusted for maternal education, maternal age, early pregnancy body mass index, parity, and any alcohol, tobacco, or marijuana use.

RESULTS

The geometric mean of PFOS and PFHxS was slightly lower among those with preeclampsia relative to those without a hypertensive disorder (e.g., geometric mean for PFOS was 1.89 and 1.94, respectively). Serum concentrations of PFAS were not strongly associated with gestational hypertension or preeclampsia in single pollutant or mixture models. For example, using quantile g-computation, a simultaneous one quartile increase in all PFAS was not associated with odds of gestational hypertension (odds ratio = 0.86, 95% CI = 0.60, 1.23), relative to those without a hypertensive disorder of pregnancy.

CONCLUSIONS

In this birth cohort of African Americans, there was no association between serum PFAS measured in early pregnancy and hypertensive disorders of pregnancy, which may be reflective of the fairly low PFAS levels in our study population.

Threats of per- and poly-fluoroalkyl pollutants to susceptible populations

Environmental exposure to per- and poly-fluoroalkyl substances (PFAS) has raised significant global health concerns due to potential hazards in healthy adults. However, the impact of PFAS on susceptible populations, including pregnant individuals, newborns, the older people, and those with underlying health conditions, has been overlooked. These susceptible groups often have physiological changes that make them less resilient to the same exposures. Consequently, there is an urgent need for a comprehensive understanding of the health risks posed by PFAS exposure to these populations. In this review, we delve into the potential health risks of PFAS exposure in these susceptible populations. Equally important, we also examine and discuss the molecular mechanisms that underlie this susceptibility. These mechanisms include the induction of oxidative stress, disruption of the immune system, impairment of cellular metabolism, and alterations in gut microbiota, all of which contribute to the enhanced toxicity of PFAS in susceptible populations. Finally, we address the primary research challenges and unresolved issues that require further investigation. This discussion aims to foster research for a better understanding of how PFAS affect susceptible populations and to pave the way for strategies to minimize their adverse effects.

First trimester plasma PER- AND Polyfluoroalkyl Substances (PFAS) and blood pressure trajectories across the second and third trimesters of pregnancy

BACKGROUND

Evidence suggests that exposure to per- and polyfluoroalkyl substances (PFAS) increases risk of high blood pressure (BP) during pregnancy. Prior studies did not examine associations with BP trajectory parameters (i.e., overall magnitude and velocity) during pregnancy, which is linked to adverse pregnancy outcomes.

OBJECTIVES

To estimate associations of multiple plasma PFAS in early pregnancy with BP trajectory parameters across the second and third trimesters. To assess potential effect modification by maternal age and parity.

METHODS

In 1297 individuals, we quantified six PFAS in plasma collected during early pregnancy (median gestational age: 9.4 weeks). We abstracted from medical records systolic BP (SBP) and diastolic BP (DBP) measurements, recorded from 12 weeks gestation until delivery. BP trajectory parameters were estimated via Super Imposition by Translation and Rotation modeling. Subsequently, Bayesian Kernel Machine Regression (BKMR) was employed to estimate individual and joint associations of PFAS concentrations with trajectory parameters - adjusting for maternal age, race/ethnicity, pre-pregnancy body mass index, income, parity, smoking status, and seafood intake. We evaluated effect modification by age at enrollment and parity.

RESULTS

We collected a median of 13 BP measurements per participant. In BKMR, higher concentration of perfluorooctane sulfonate (PFOS) was independently associated with higher magnitude of overall SBP and DBP trajectories (i.e., upward shift of trajectories) and faster SBP trajectory velocity, holding all other PFAS at their medians. In stratified BKMR analyses, participants with ≥ 1 live birth had more pronounced positive associations between PFOS and SBP velocity, DBP magnitude, and DBP velocity - compared to nulliparous participants. We did not observe significant associations between concentrations of the overall PFAS mixture and either magnitude or velocity of the BP trajectories.

CONCLUSION

Early pregnancy plasma PFOS concentrations were associated with altered BP trajectory in pregnancy, which may impact future cardiovascular health of the mother.

Exploring the impact of prenatal perfluoroalkyl and polyfluoroalkyl substances exposure on blood pressure in early childhood: A longitudinal analysis

Previous research investigating the correlation between prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and subsequent blood pressure (BP) in offspring has yielded limited and contradictory findings. This study was conducted to investigate the potential relationship between maternal PFAS levels during pregnancy and subsequent BP in early childhood. A total of 129 expectant mothers from the Shanghai Birth Cohort were included in the study. Using high-performance liquid chromatography/tandem mass spectrometry, we measured ten PFAS compounds in maternal plasma throughout the pregnancy. When the children reached the age of 4, we examined their systolic BP (SBP) and diastolic BP (DBP), along with mean arterial pressure (MAP) and pulse pressure (PP). Data interpretation employed multiple linear and logistic regression models, complemented by Bayesian kernel machine regression (BKMR).We found that the majority of PFAS concentrations remained stable during pregnancy. The linear and BKMR models indicated a positive relationship between the PFAS mixture in maternal plasma and offspring's DBP and MAP, with perfluorohexanesulphonic acid (PFHxS) having the most significant influence (PFHxS and DBP [first trimester:β=3.03, 95%CI: (1.01,5.05); second trimester: β=2.35, 95%CI: (0.94,3.75); third trimester: β=2.57, 95%CI:(0.80,4.34)]; MAP [first trimester:β=2.55, 95%CI: (0.64,4.45); second trimester: β=2.28, 95%CI: (0.95,3.61); third trimester: β=2.35, 95%CI:(0.68,4.01)]). Logistic regression highlighted an increased risk of prehypertension and hypertension in offspring with higher maternal PFHxS concentrations during all three trimesters [first trimester: OR=2.53, 95%CI:(1.11,5.79), second trimester: OR=2.05, 95%CI:(1.11,3.78), third trimester: OR=3.08, 95%CI:(1.40,6.79)]. A positive correlation was identified between the half-lives of PFAS and the odds ratio (OR) of prehypertension and hypertension in childhood (β=0.139, P=0.010). In conclusion, this research found maternal plasma PFAS concentrations to be positively associated with BP in offspring, with PFHxS showing the most significant influence. This correlation remained consistent throughout pregnancy, and this effect was proportional to the half-lives of PFAS.

Association between prenatal perfluorinated compounds exposure and risk of pregnancy complications: A meta-analysis

BACKGROUND AND OBJECTIVE

Per- and polyfluoroalkyl substances (PFASs) have been shown to be persistent and bioaccumulative. An elevated danger of pregnancy complications perhaps connected with exposure to PFASs, but the potential effects remain elusive. The objective of this study is to investigate the possible association between PFASs exposure and pregnancy complications, drawing upon existing evidence.

METHODS

Electronic databases of PubMed, Qvid Medline, Embase, and Web of Science were searched thoroughly to identify eligible research published prior to November 28, 2023, examining the relationship between PFASs and pregnancy-related complications. To evaluate the quality of observational studies incorporated into the article, the Strengthening Reporting of Observational Studies in Epidemiology (STROBE) tool was utilized. The main outcomes assessed in this study included gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), gestational hypertension (GH), and preeclampsia (PE).

RESULTS

Twenty-five relevant studies involving 30079 participants were finally selected from four databases. The combined estimates indicate that prenatal exposure to perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorobutane sulfonic acid (PFBS), and perfluoroenanthic acid (PFHpA) is associated with gestational diabetes mellitus (GDM) (PFOA: OR = 1.45, 95%CI: 1.07-1.94, P = 0.015; PFHxS: OR = 1.16, 95%CI: 1.00-1.36, P = 0.055; PFBS: OR = 1.44, 95%CI: 1.16-1.79, P = 0.001; PFHpA: OR = 1.41, 95%CI: 1.10-1.82, P = 0.008). The exposure to PFBS is positively associated with HDP (OR = 1.27, 95%CI: 1.14-1.41, P < 0.001), while both PFOA and PFHpA demonstrate statistically significant positive correlations with GH (PFOA: OR = 1.09, 95%CI: 1.00-1.19, P = 0.049; PFHpA: OR = 1.43, 95%CI: 1.15-1.78, P = 0.001). Negative correlations were observed for prenatal perfluorododecanoic acid (PFDoA) exposure and GH (OR = 0.71, 95%CI: 0.57-0.87, P = 0.001). However, no compelling evidence was identified to link PFASs exposure with the risk of PE.

CONCLUSION

According to the meta-analysis findings, exposure to PFASs may be linked to GDM, HDP, and GH, but it does not significantly raise the risk of PE alone. Further research with larger sample size is required to verify this potential association and explore the biological mechanisms.

Association of PFDeA exposure with hypertension (NHANES, 2013-2018)

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) is a series of artificial compounds which is associated with human health. However, there are few studies on the relationship between PFASs and hypertension. In this study, we examined the association between different kinds of PFASs and hypertension. Multivariable logistic regression and subgroup analysis were adopted to assess the associations between PFASs and hypertension. Spline smoothing plots and linear regression were used to assess the relationship between PFASs and blood pressure. We found a positive association between serum PFDeA concentrations and the prevalence of hypertension after fully adjusting confounders (OR = 1.2, P = 0.01), but other types of PFASs showed no positive results. Subgroup analysis stratified by ethnicity showed there was a stronger relationship among non-Hispanics than Hispanics. Serum PFDeA concentrations were positively associated with systolic pressure (β = 0.7, P< 0.01) and diastolic blood pressure (β = 0.8, P< 0.01) among non-Hispanics who did not take antihypertensive drugs. This study showed that PFDeA exposure was associated with hypertension in Americans who identify as non-Hispanic. There was a positive association between PFDeA and blood pressure in non-Hispanic Americans who did not take antihypertensive drugs.

Gestational hypertension, preeclampsia, and gestational diabetes mellitus after high exposure to perfluoroalkyl substances from drinking water in Ronneby, Sweden

BACKGROUND

Leakage of fire-fighting foam from an airfield caused contamination of the drinking water supplied to a third of the population in Ronneby, resulting in very high serum levels of predominantly perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS). The results of studies investigating the association between exposure to perfluorinated alkyl substances (PFAS) and pregnancy complications are inconsistent, and studies at high exposures of PFOS and PFHxS are lacking.

OBJECTIVES

To investigate the association between exposure to high levels of PFAS and gestational hypertension and preeclampsia, and gestational diabetes mellitus.

METHODS

We retrieved data on 27 292 childbirths between 1995 and 2013 from the National Medical Birth Register for women that had a residential address in Blekinge county for at least one year before delivery. Residential history was used as a proxy for exposure by categorizing women into high-, intermediate-, or background exposed based on their residential address during the five-year period before childbirth. Data on confounders were retrieved from administrative registers. The outcomes were defined based on International Classification of Diseases codes. We used logistic regression to estimate odds ratios (OR) for gestational hypertension and preeclampsia, and gestational diabetes mellitus. We also investigated effect modification by fetal sex.

RESULTS

We found no evidence of increased risk of gestational hypertension and preeclampsia (OR 0.80; CI 0.63-1.03), nor gestational diabetes (OR 1.03; CI 0.67-1.58) after high PFAS exposure. There was no effect modification by fetal sex.

DISCUSSION

This was the first study to investigate the association between high exposure to PFOS and PFHxS and pregnancy complications. The results from this study add important knowledge to public health management as new hotspots with high levels of PFAS are continuously discovered.

Associations between the chemical exposome and pregnancy induced hypertension

Exposure to environmental chemicals has been linked to an increased risk of pregnancy-induced hypertension (PIH). This prospective cohort study examined the associations between PIH and maternal chemical exposure to four classes of chemicals (i.e., phthalates, bisphenols, perfluoroalkyl acids, non-essential metals and trace minerals). Participants included 420 pregnant women from the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort who had data available on diagnosed PIH and environmental chemical exposure. Twelve phthalate metabolites, two bisphenols, eight perfluoroalkyl acids and eleven non-essential metals or trace minerals were quantified in maternal urine or blood samples collected in the second trimester of pregnancy. Associations between the urinary and blood concentrations of these chemicals and PIH were assessed using multiple logistic and LASSO regression analyses in single- and multi-chemical exposure models, respectively. Thirty-five (8.3%) participants were diagnosed with PIH. In single chemical exposure models, two phthalate metabolites, mono-methyl phthalate (MMP) and monoethyl phthalate (MEP), three perfluoroalkyl acids, perfluoroheptanoic acid (PFHpA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA), and one metal, manganese, were associated with increased odds of PIH. The metabolites of di (2-ethylhexyl) phthalate (DEHP) and the molar sum of these metabolites, as well as antimony, displayed trend associations (p < 0.10). In multi-chemical exposure models using LASSO penalized regressions and double-LASSO regressions, MEP (AOR: 1.43, 95% CI: 1.09-1.88, p = 0.009) and PFNA (AOR: 2.03, 95% CI: 1.01-4.07, p = 0.04) were selected as the chemicals most highly associated with PIH. These findings suggest that maternal levels of phthalates and perfluoroalkyl acids may be associated with the diagnosis on PIH. Future research should consider both individual and multi-chemical exposures when examining predictors of PIH and other maternal cardiometabolic health disorders, such as preeclampsia, eclampsia, HELLP syndrome, and gestational diabetes.

Evaluating the Effect of Gestational Exposure to Perfluorohexane Sulfonate on Placental Development in Mice Combining Alternative Splicing and Gene Expression Analyses

BACKGROUND

Perfluorohexane sulfonate (PFHxS) is a frequently detected per- and polyfluoroalkyl substance in most populations, including in individuals who are pregnant, a period critical for early life development. Despite epidemiological evidence of exposure, developmental toxicity, particularly at realistic human exposures, remains understudied.

OBJECTIVES

We evaluated the effect of gestational exposure to human-relevant body burden of PFHxS on fetal and placental development and explored mechanisms of action combining alternative splicing (AS) and gene expression (GE) analyses.

METHODS

Pregnant ICR mice were exposed to 0, 0.03, and 0.3 μ g / kg / day  from gestational day 7 to day 17 via oral gavage. Upon euthanasia, PFHxS distribution was measured using liquid chromatography-tandem mass spectrometry. Maternal and fetal phenotypes were recorded, and histopathology was examined for placenta impairment. Multiomics was adopted by combining AS and GE analyses to unveil disruptions in mRNA quality and quantity. The key metabolite transporters were validated by quantitative real-time PCR (qRT-PCR) for quantification and three-dimensional (3D) structural simulation by AlphaFold2. Targeted metabolomics based on liquid chromatography-tandem mass spectrometry was used to detect amino acid and amides levels in the placenta.

RESULTS

Pups developmentally exposed to PFHxS exhibited signs of intrauterine growth restriction (IUGR), characterized by smaller fetal weight and body length (p < 0.01 ) compared to control mice. PFHxS concentration in maternal plasma was 5.01 ± 0.54  ng / mL . PFHxS trans-placenta distribution suggested dose-dependent transfer through placental barrier. Histopathology of placenta of exposed dams showed placental dysplasia, manifested with an attenuated labyrinthine layer area and deescalated blood sinus counts and placental vascular development index marker CD34. Combined GE and AS analyses pinpointed differences in genes associated with key biological processes of placental development, proliferation, metabolism, and transport in placenta of exposed dams compared to that of control dams. Further detection of placental key transporter gene expression, protein structure simulation, and amino acid and amide metabolites levels suggested that PFHxS exposure during pregnancy led to impairment of placental amino acid transportation.

DISCUSSION

The findings from this study suggest that exposure to human-relevant very-low-dose PFHxS during pregnancy in mice caused IUGR, likely via downregulating of placental amino acid transporters, thereby impairing placental amino acid transportation, resulting in impairment of placental development. Our findings confirm epidemiological findings and call for future attention on the health risk of this persistent yet ubiquitous chemical in the early developmental stage and provide a new approach for understanding gene expression from both quantitative and qualitative omics approaches in toxicological studies. https://doi.org/10.1289/EHP13217.

Per- and Poly-fluoroalkyl Substances and Bile Acid Profiles in Pregnant Women

Alterations in bile acid (BA) profiles are closely associated with adverse outcomes in pregnant women and their offspring and may be one potential pathway underlying the related metabolic effects of per- and poly-fluoroalkyl substances (PFAS) exposure. However, evidence of associations between PFAS exposure and BA profiles in pregnant women is scarce. This study examined the associations of individual PFAS and PFAS mixture with BA profiles of pregnant women. We obtained quantitative data on the plasma concentrations of 13 PFAS and 15 BAs in 645 pregnant women from the Jiashan birth cohort. In Bayesian kernel machine regression models, the PFAS mixture was associated with increased plasma CA, TCA, TCDCA, and GLCA levels but with decreased GCA and LCA concentrations. Furthermore, the PFAS mixture was associated with increased concentrations of total BAs and the secondary/primary BA ratio but with decreased conjugated/unconjugated and glycine/taurine-conjugated BA ratios. PFHxS, PFUdA, PFOS, PFNA, and PFDA were the dominant contributors. The results of the linear regression analysis of individual PFAS were generally similar. Our findings provide the first epidemiological evidence for the associations of a PFAS mixture with BA profiles in pregnant women and may provide explanatory insights into the biological pathways underlying the related metabolic effects of PFAS exposure.

Relative Risks of Adverse Perinatal Outcomes in Three Australian Communities Exposed to Per- and Polyfluoroalkyl Substances: Data Linkage Study

INTRODUCTION

Firefighting foams containing per- and polyfluoroalkyl substances (PFAS) have caused environmental contamination in several Australian residential areas, including Katherine in the Northern Territory (NT), Oakey in Queensland (Qld), and Williamtown in New South Wales (NSW). We examined whether the risks of adverse perinatal outcomes were higher in mothers living in these exposure areas than in selected comparison areas without known contamination.

METHODS

We linked residential addresses in exposure areas to addresses collected in the jurisdictional Perinatal Data Collections of the NT (1986-2017), Qld (2007-2018), and NSW (1994-2018) to select all pregnancies from mothers who gave birth while living in these areas. We also identified one comparison group for each exposure area by selecting pregnancies where the maternal address was in selected comparison areas. We examined 12 binary perinatal outcomes and three growth measurements. For each exposure area, we estimated relative risks (RRs) of adverse outcomes and differences in means of growth measures, adjusting for sociodemographic characteristics and other potential confounders.

RESULTS

We included 16,970 pregnancies from the NT, 4654 from Qld, and 7475 from NSW. We observed elevated risks of stillbirth in Oakey (RR = 2.59, 95% confidence interval (CI) 1.25 to 5.39) and of postpartum haemorrhage (RR = 1.94, 95% CI 1.13 to 3.33) and pregnancy-induced hypertension (RR = 1.88, 95% CI 1.30 to 2.73) in Williamtown. The risks of other perinatal outcomes were not materially different from those in the relevant comparison areas or were uncertain due to small numbers of events.

CONCLUSIONS

There was limited evidence for increased risks of adverse perinatal outcomes in mothers living in areas with PFAS contamination from firefighting foams. We found higher risks of some outcomes in individual areas, but these were not consistent across all areas under study and could have been due to chance, bias, or confounding.

Restoring Angiotensin Type 2 Receptor Function Reverses PFOS-Induced Vascular Hyper-Reactivity and Hypertension in Pregnancy

Perfluorooctane sulfonic acid (PFOS) exposure during pregnancy induces hypertension with decreased vasodilatory angiotensin type-2 receptor (AT2R) expression and impaired vascular reactivity and fetal weights. We hypothesized that AT2R activation restores the AT1R/AT2R balance and reverses gestational hypertension by improving vascular mechanisms. Pregnant Sprague-Dawley rats were exposed to PFOS through drinking water (50 μg/mL) from gestation day (GD) 4-20. Controls received drinking water with no detectable PFOS. Control and PFOS-exposed rats were treated with AT2R agonist Compound 21 (C21; 0.3 mg/kg/day, SC) from GD 15-20. In PFOS dams, blood pressure was higher, blood flow in the uterine artery was reduced, and C21 reversed these to control levels. C21 mitigated the heightened contraction response to Ang II and enhanced endothelium-dependent vasorelaxation in uterine arteries of PFOS dams. The observed vascular effects of C21 were correlated with reduced AT1R levels and increased AT2R and eNOS protein levels. C21 also increased plasma bradykinin production in PFOS dams and attenuated the fetoplacental growth restriction. These data suggest that C21 improves the PFOS-induced maternal vascular dysfunction and blood flow to the fetoplacental unit, providing preclinical evidence to support that AT2R activation may be an important target for preventing or treating PFOS-induced adverse maternal and fetal outcomes.

Biomonitoring of perfluoroalkyl and polyfluoroalkyl substances (PFAS) from the Survey of the Health of Wisconsin (SHOW) 2014-2016 and comparison with the National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are a growing class of manufactured chemical compounds found in a variety of consumer products. PFAS are ubiquitous in the environment and were found in many humans sampled in the United States (U.S.). Yet, significant gaps in understanding statewide levels of exposure to PFAS remain.

OBJECTIVE

The goals of this study are to establish a baseline of exposure at the state level by measuring PFAS serum levels among a representative sample of Wisconsin residents and compare to United States National Health and Nutrition Examination Survey (NHANES).

METHODS

The study sample included 605 adults (18+ years of age) selected from the 2014-2016 sample of the Survey of the Health of Wisconsin (SHOW). Thirty-eight PFAS serum concentrations were measured using high-pressure liquid chromatography coupled with tandem mass spectrometric detection (HPLC-MS/MS) and geometric means were presented. Weighted geometric mean serum values of eight PFAS analytes from SHOW were compared to U.S. national levels from the NHANES 2015-2016 sample (PFOS, PFOA, PFNA, PFHxS, PFHpS, PFDA, PFUnDA), and the 2017-2018 sample for Me-PFOSA, PFHPS using the Wilcoxon rank-sum test.

RESULTS

PFOS, PFHxS, PFHpS, PFDA, PFNA, and PFOA were detected in over 96% of SHOW participants. In general, SHOW participants had lower serum levels across all PFAS when compared to NHANES. Serum levels increased with age and were higher among males and whites. Similar trends were seen in NHANES, except non-whites had higher PFAS levels at higher percentiles in NHANES.

IMPACT STATEMENT

The present study conducts biomonitoring of 38 PFAS among representative sample of residents in the state of Wisconsin. Results suggest that while the majority of Wisconsin residents tested have detectable levels of PFAS in their blood serum, they may have a lower body burden of some PFAS compared to a nationally representative sample. Older adults, males, and whites may have a higher body burden of PFAS relative to other groups, both in Wisconsin and the wider United States.

Perfluoroalkyl and polyfluoroalkyl substances and hypertensive disorders of pregnancy: A systematic review and meta-analysis

Hypertensive disorders of pregnancy (HDP), including gestational hypertension (GH) and preeclampsia (PE), cause significant morbidity and mortality among pregnant women. Several environmental toxins, particularly those that affect the normal function of the placenta and the endothelium, are emerging as potential risk factors for HDP. Among them, per- and polyfluoroalkyl substances (PFAS), widely used in a variety of commercial products, have been related to a variety of adverse health effects including HDP. This study was conducted by searching three databases for observational studies reporting associations between PFAS and HDP, all of which were published before December 2022. We used random-effects meta-analysis to calculate pooled risk estimates, and assessing each combination of exposure and outcome for quality and level of evidence. In total, 15 studies were included in the systematic review and meta-analysis. The results from meta-analyses showed that risk of PE was increased with exposure to PFOA (perfluorooctanoic acid) (RR = 1.39, 95% CI = 1.05, 1.85; N = 6 studies; exposure = 1 ln-unit increment; low certainty), PFOS (perfluorooctane sulfonate) (RR = 1.51, 95% CI = 1.23, 1.86; N = 6 studies; exposure = 1 ln-unit increment; moderate certainty), and PFHxS (perfluorohexane sulfonate) (RR = 1.39, 95% CI = 1.10, 1.76; N = 6 studies; exposure = 1 ln-unit increment; low certainty). PFOS was also associated with an increased risk of HDP (RR = 1.39, 95% CI = 1.10, 1.76; exposure = 1 ln-unit increment; low certainty). Exposure to legacy PFAS (PFOA, PFOS, PFHxS) is associated with an increased risk of PE, and PFOS is further associated with HDP. In view of the limitations of meta-analysis and quality of evidence, these findings should be interpreted with caution. Further research is required that assesses exposure to multiple PFAS in diverse and well-powered cohorts.

Prenatal exposure to perfluoroalkyl substances and inflammatory biomarker concentrations

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that induce immunotoxicity in experimental studies; however, epidemiological evidence-particularly during pregnancy-is scarce. We quantified associations between first trimester plasma perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and perfluorohexane sulfonate (PFHxS) concentrations and third trimester concentrations of inflammatory biomarkers and determined if these associations were modified by fetal sex.

Methods

We analyzed data from 1411 participants, recruited between 2008 and 2011, in the Maternal-Infant Research on Environmental Chemicals study. Our primary outcome was a composite inflammatory index derived by summing the z-scores of eight proinflammatory biomarkers. Using multivariable linear regression models, we quantified associations between each PFAS and the inflammatory index and individual biomarkers. We quantified the effects of the PFAS mixture using weighted quantile sum regression, and evaluated effect modification using product terms and sex-stratified models.

Results

Each doubling of PFOA and PFHxS was associated with a 0.38 (95% CI, 0.09, 0.67) and 0.21 (95% CI, 0.01, 0.41) SD increase in the proinflammatory index, respectively. A one-quartile increase in the PFAS mixture was associated with a 0.40 (95% CI, 0.09, 0.71) SD increase in the proinflammatory index. In individual models, we observed positive associations between PFAS and concentrations of monocyte chemoattractant protein-1, macrophage inflammatory protein-1β, and matrix metalloproteinases-9; however, the magnitude and precision varied according to the specific PFAS. Sex-specific findings were identified in few PFAS-biomarker associations.

Conclusions

PFOA, PFOS, and PFHxS, individually and as a mixture, were positively associated with proinflammatory biomarkers during pregnancy.

Developmental toxicity of perfluorohexane sulfonate at human relevant dose during pregnancy via disruption in placental lipid homeostasis

Perfluorohexyl sulfonate (PFHxS) is the third most abundant per- and polyfluoroalkyl substances and its developmental toxicity remains very poorly understood. Here, pregnant mice exposed to PFHxS at human relevant dose showed increased fetal death incidence in the high-dose PFHxS-H group (P < 0.01). Body distribution analyses suggested that PFHxS crossed the placental barrier reaching the fetus in a dose-dependent manner. Histopathological data demonstrated impairment in the placenta with reduced blood sinus volume, placental labyrinth area as well as thickness of labyrinthine layer. Further lipidomic and transcriptomic data together showed that PFHxS exposure caused significant disruption in placental lipid homeostasis, including total lipid accumulation in the placenta, and dysregulation in phospholipid and glycerol lipid metabolism. Gene expression analyses uncovered elevation in key placental fatty acid transporters including fabp2, whereas protein expression showed transporter specific disruptions following exposure. Together, gestational exposure to human relevant level of PFHxS may increase the incidence of fetal deaths and caused placental dysplasia via disruption in lipid metabolism homeostasis. These findings raise the concern regarding the highly prevalent and persistent chemical towards early sensitive developing stages and provide basis for further understanding of its effects on lipid metabolism and underlying mechanisms.

Dietary and maternal sociodemographic determinants of perfluoroalkyl and polyfluoroalkyl substance levels in pregnant women

Diet, including drinking water, and demographic characteristics have been associated with PFAS exposure levels in the general population. But data in pregnant women are scarce. We aimed to examine the PFAS levels in relation to these factors in early pregnancy and included 2545 pregnant women in early pregnancy from the Shanghai Birth Cohort. Ten PFAS were measured using high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS-MS) in plasma samples at around 14 weeks of gestation. Geometric mean (GM) ratios were used to estimate the associations between demographic characteristics, food intake and source of drinking water and concentrations of nine PFAS with a detection rate of at least 70%, and the total perfluoroalkyl carboxylic acids (∑PFCA), perfluoroalkyl sulfonic acids (∑PFSA) and all the PFAS concentrations (∑PFAS). Median concentrations of plasma PFAS ranged from 0.03 ng/mL for PFBS to 11.56 ng/mL for PFOA. In the multivariable linear models, maternal age, parity, parental education level, marine fish, freshwater fish, shellfish, shrimps, crabs, animal kidneys, animal liver, eggs, and bone soup in early pregnancy were positively associated with plasma concentrations of certain PFAS. Whereas pre-pregnancy BMI, plant-based foods, and drinking bottled water were negatively associated with some PFAS concentrations. In summary, this study suggested that fish and seafood, animal offal, and high-fat foods (eggs and bone soup) were significant sources of PFAS. PFAS exposure may be reduced by consuming more plant-based foods and potential interventions, such as drinking water treatment.

A review of cardiovascular effects and underlying mechanisms of legacy and emerging per- and polyfluoroalkyl substances (PFAS)

Cardiovascular disease (CVD) poses the leading threats to human health and life, and their occurrence and severity are associated with exposure to environmental pollutants. Per- and polyfluoroalkyl substances (PFAS), a group of widely used industrial chemicals, are characterized by persistence, long-distance migration, bioaccumulation, and toxicity. Some PFAS, particularly perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexanesulfonic acid (PFHxS), have been banned, leaving only legacy exposure to the environment and human body, while a number of novel PFAS alternatives have emerged and raised concerns, such as polyfluoroalkyl ether sulfonic and carboxylic acid (PFESA and PFECA) and sodium p-perfluorous nonenoxybenzene sulfonate (OBS). Overall, this review systematically elucidated the adverse cardiovascular (CV) effects of legacy and emerging PFAS, emphasized the dose/concentration-dependent, time-dependent, carbon chain length-dependent, sex-specific, and coexposure effects, and discussed the underlying mechanisms and possible prevention and treatment. Extensive epidemiological and laboratory evidence suggests that accumulated serum levels of legacy PFAS possibly contribute to an increased risk of CVD and its subclinical course, such as cardiac toxicity, vascular disorder, hypertension, and dyslipidemia. The underlying biological mechanisms may include oxidative stress, signaling pathway disturbance, lipid metabolism disturbance, and so on. Various emerging alternatives to PFAS also play increasingly prominent toxic roles in CV outcomes that are milder, similar to, or more severe than legacy PFAS. Future research is recommended to conduct more in-depth CV toxicity assessments of legacy and emerging PFAS and explore more effective surveillance, prevention, and treatment strategies, accordingly.

Per- and Polyfluoroalkyl Substances and Outcomes Related to Metabolic Syndrome: A Review of the Literature and Current Recommendations for Clinicians

Per- and polyfluoroalkyl substances (PFAS) are a class of toxic, ubiquitous, anthropogenic chemicals known to bioaccumulate in humans. Substantial concern exists regarding the human health effects of PFAS, particularly metabolic syndrome (MetS), a precursor to cardiovascular disease, the leading cause of mortality worldwide. This narrative review provides an overview of the PFAS literature on 4 specific components of MetS: insulin resistance/glucose dysregulation, central adiposity, dyslipidemia, and blood pressure. We focus on prospective cohort studies as these provide the best body of evidence compared to other study designs. Available evidence suggests potential associations between some PFAS and type-2 diabetes in adults, dyslipidemia in children and adults, and blood pressure in adults. Additionally, some studies found that sex and physical activity may modify these relationships. Future studies should consider modification by sex and lifestyle factors (e.g., diet and physical activity), as well quantifying the impact of PFAS mixtures on MetS features and related clinical disease. Finally, clinicians can follow recently developed clinical guidance to screen for PFAS exposure in patients, measure PFAS levels, conduct additional clinical care based on PFAS levels, and advise on PFAS exposure reduction.

In utero exposure to per-/polyfluoroalkyl substances (PFASs): Preeclampsia in pregnancy and low birth weight for neonates

Per-/polyfluoroalkyl substances (PFASs) have been linked to preeclampsia with inconsistent directions for outcomes. However, information regarding the joint effects of PFASs mixtures on preeclampsia as well as their associations with the low birth weight (LBW) and small for gestational age (SGA) is nascent. The present study included 82 women with preeclampsia and 169 healthy participants from Hangzhou, China. Fifteen PFASs were analyzed in maternal serum before delivery. PFOA and 6:2Cl-PFESA were associated with higher incidence of preeclampsia both linearly and by tertile. Each log-unit increase in serum PFOA (OR:5.29, 95% CI: 1.05, 26.7, p = 0.044) and 6:2 Cl-PFESA (OR:1.02, 95%CI: 1.00, 1.48, p = 0.045) concentrations were associated with increased risks of preeclampsia. These effects were more profound among primiparous women carrying female fetuses. Both PFOA and PFUnDA concentrations were significantly associated with higher odds of early-onset preeclampsia, but the associations tended to be null for late-onset. In addition, each logarithmic increment in PFOA concentrations were significantly associated with a 0.262 and 0.224 mmHg increase in systolic (95% CI: 0.147, 0.377) and diastolic (95% CI: 0.133, 0.314) blood pressures. Using Bayesian kernel machine regressions (BKMR), the overall effects of PFASs mixture concentrations on preeclampsia showed an increasing trend, with PFOA being the largest contributor. With regard to birth weight, the Cox proportional hazards model indicated that significantly higher risks of the LBW were associated with preeclampsia than normal pregnancy (OR: 4.56, 95% CI: 2.44, 6.68, p = 0.000). Increased LBW risks were found for the higher PFOA exposure both linearly and by tertile. Besides, serum PFOA and PFUnDA concentrations were significantly associated with higher odds of SGA development. Nevertheless 4:2 FTS and ADONA were inversely associated with LBW and SGA incidences. Further adverse birth outcomes should be explored to elucidate the health implications of PFASs exposure and preeclampsia development.

Exposure to endocrine-disrupting chemicals and risk of gestational hypertension and preeclampsia: A systematic review and meta-analysis

Prenatal exposure to endocrine-disrupting chemicals has been linked to gestational hypertension (GH) and preeclampsia (PE). However, the results were conflicting and inconclusive. We conducted a systematic review and meta-analysis for an overview of these relationships. We searched PubMed, and Google Scholar for studies investigating bisphenol A, phthalates, and per or poly-fluoroalkyl substances and GH or PE. Pooled odds ratio (OR) with a 95% confidence interval (CI) were calculated for risk estimate using the generic inverse variance method. A total of 14 studies were included in the present analysis. The pooled results demonstrated that perfluorooctanoic acid (PFOA, OR:1.20, 95% CI: 1.04, 1.39), perfluoro octane sulfonic acid (PFOS, (OR:1.23, 95% CI: 1.10, 1.38), and perfluononanoic acid (PFNA, OR:1.20, 95% CI: 1.03, 1.40) were significantly associated with an increased risk of PE. There was no significant association observed with perfluoro hexane sulfonic acid (PFHxS), perfluoro decanoic acid (PFDA), perfluoro heptanoic acid (PFHpA), and perfluoro undecanoic acid (PFUnDA) and PE. For GH, a statistically significant positive association was found with PFOA (OR:1.18, 95% CI: 1.01, 1.39) and PFHxS (OR:1.15, 95% CI: 1.02, 1.29). Among various phthalates analysed only mono-ethyl phthalate (MEP, OR:1.37, 95% CI: 1.11, 1.70) showed an association with GH. From our analysis, bisphenol A exposure during pregnancy did not show a significant association with the risk of PE. Our findings indicated that exposure to PFASs such as PFOA, PFOS, and PFNA during pregnancy is associated with an increased risk of PE and PFOA and PFHxS with GH. We also found that MEP was associated with GH. Most of the results were unstable in sensitivity analysis. Since most of these associations have limited evidence, more research is needed to confirm these findings.

Associations of perfluoroalkyl and polyfluoroalkyl substances with gestational hypertension and blood pressure during pregnancy: A cohort study

Previous studies have reported inconsistent associations between perfluoroalkyl and polyfluoroalkyl substances (PFAS) and gestational hypertension (GH) and blood pressure (BP) during pregnancy. Herein, we aimed to evaluate individual and overall effects of PFAS on GH and longitudinal BP measures during pregnancy. We included 826 pregnant women from the Jiashan Birth Cohort established between 2016 and 2018. Concentrations of thirteen PFAS were quantified using plasma samples collected within 16 weeks of gestation. Longitudinal BP measures were obtained from medical records, and more than nine measurements were available for 85.60% of participants. GH was defined as new-onset hypertension occurring after 20 weeks of gestation. Logistic regression models were used to examine the effect of PFAS on GH, while generalized estimating equation models evaluated the average effect of PFAS on BP in each trimester. The potential effect modification by fetal sex was also examined. Bayesian kernel machine regression (BKMR) and quantile g-computation (QgC) were implemented to explore the overall effect of the PFAS mixture. PFOA, PFOS, and PFHxS presented the highest median concentrations of 11.99, 8.81 and 5.43 ng/mL, respectively. Overall, 5.57% of subjects developed GH. PFOS, PFDA, PFUdA, and PFDoA were significantly associated with lower GH odds, and odds ratios ranged between 0.62 and 0.68. We noted associations between PFAS and lower systolic BP and diastolic BP in the third trimester, with PFDA and PFUdA exhibiting the effect on systolic BP only in pregnant women carrying a female fetus. These associations were further confirmed by BKMR and QgC, showing an inverse overall effect of the PFAS mixture. Higher concentrations of PFAS during early pregnancy were associated with lower GH risk and longitudinal BP measures in the third trimester in a population with relatively high exposure levels. Fetal sex might modify the effects of PFDA and PFUdA on systolic BP in the third trimester.

Association of single and multiple prefluoroalkyl substances exposure with preterm birth: Results from a Chinese birth cohort study

BACKGROUND

Perfluoroalkyl substances (PFASs) are persistent organic pollutants that may lead the adverse birth outcomes, including preterm birth (PTB). However, previous studies have reported inconsistent results on the association between PFASs and PTB, and lack of the epidemiological evidence regarding the effect of PFASs mixture on PTB. This study aimed to explore association of individual and multiple exposure to PFASs with PTB.

METHODS

The study subjects were consisted of 1341 pregnant women from Guangxi Zhuang Birth Cohort in Guangxi, China, from June 2015 to April 2019. Nine PFASs concentrations in the maternal serum were examined by ultrahigh liquid performance chromatography-tandem mass spectrometry, and the gestational weeks were obtained from medical records. We applied binary logistics regression model to explore correlation between individual PFAS and PTB and inspected the combined effect of PFASs mixture on PTB by applying Bayesian kernel machine regression (BKMR) and weighted quantile sum (WQS) regression models.

RESULTS

In adjusted logistics regression model, perfluorooctane sulfonate (PFOS), perfluoroheptanoic acid (PFHpA), perfluorobutanesulfonic acid (PFBS), ∑perfluorinated sulfonic acids (PFSA), and ∑PFASs were positively associated with the risk of PTB. In contrast, perfluoroundecanoic acid (PFUnA), perfluorohexane sulfonate (PFHxS), and perfluorooctanoic acid (PFOA) were negatively associated with the risk of PTB. These associations of n PFOS and PFHpA with PTB were found to be more pronounced in male infants. Restricted cubic splines (RCSs) showed an inverse U-shaped relationship between PFBS and PTB. Analysis from BKMR model showed a positive association between PFASs mixture and PTB, and no evidence of interactions among the nine PFASs were detected. Additionally, PFHpA, PFOS, and PFBS were identified as the main contributors for the effect of PFASs mixture on increasing the risk of PTB by BKMR and WQS models.

CONCLUSION

Prenatal exposure to higher levels of PFASs mixture was associated with higher risk of PTB.

Evaluating maternal exposure to an environmental per and polyfluoroalkyl substances (PFAS) mixture during pregnancy: Adverse maternal and fetoplacental effects in a New Zealand White (NZW) rabbit model

Mixtures of per- and polyfluoroalkyl substances (PFAS) are often found in drinking water, and serum PFAS are detected in up to 99% of the population. However, very little is known about how exposure to mixtures of PFAS affects maternal and fetal health. The aim of this study was to investigate maternal, fetal, and placental outcomes after preconceptional and gestational exposure to an environmentally relevant PFAS mixture in a New Zealand White (NZW) rabbit model. Dams were exposed via drinking water to control (no detectable PFAS) or a PFAS mixture for 32 days. This mixture was formulated with PFAS to resemble levels measured in tap water from Pittsboro, NC (10 PFAS compounds; total PFAS load = 758.6 ng/L). Maternal, fetal, and placental outcomes were evaluated at necropsy. Thyroid hormones were measured in maternal serum and kit blood. Placental gene expression was evaluated by RNAseq and qPCR. PFAS exposure resulted in higher body weight (p = 0.01), liver (p = 0.01) and kidney (p = 0.01) weights, blood pressure (p = 0.05), and BUN:CRE ratio (p = 0.04) in dams, along with microscopic changes in renal cortices. Fetal weight, measures, and histopathology were unchanged, but a significant interaction between dose and sex was detected in the fetal: placental weight ratio (p = 0.036). Placental macroscopic changes were present in PFAS-exposed dams. Dam serum showed lower T4 and a higher T3:T4 ratio, although not statistically significant. RNAseq revealed that 11 of the 14 differentially expressed genes (adj. p < 0.1) are involved in placentation or pregnancy complications. In summary, exposure elicited maternal weight gain and signs of hypertension, renal injury, sex-specific changes in placental response, and differential expression of genes involved in placentation and preeclampsia. Importantly, these are the first results to show adverse maternal and placental effects of an environmentally-relevant PFAS mixture in vivo.

Mothers living with contamination of perfluoroalkyl substances: an assessment of the perceived health risk and self-reported diseases

Widespread contamination of the superficial, drinking, and groundwater by perfluoroalkyl substances (PFASs) was discovered in the Veneto Region (northeast of Italy) in 2013. Mothers from the contaminated area were concerned about the effects of PFAS on their own and their children's health. We determined the factors that influenced the perceived risk of PFAS and the presence of self-reported diseases by conducting a study with 384 mothers of children aged 1-13 years living in the contaminated area (Red Zone, Veneto, Italy). Information on demography, the sources of exposure, and the health condition of the mothers was collected through an online survey. The serum PFAS concentration was recorded for some of the participants. We determined the factors influencing the perceived risk, risk of health outcomes, and serum PFAS levels through regression analyses. The PFAS perceived risk of the mothers increased with an increase in the trust in scientific institutions and social media, and when many friends were present, trust in politics and full-time employment had a protective effect. The PFAS perceived risk increased the occurrences of self-reported and autoimmune diseases. Longer residence (> 20 years) in the most exposed area (Red Zone A) increased the frequency of some health outcomes. Serum PFAS concentrations decreased with breastfeeding, but increased with tap water consumption, residence in Red Zone A, and residence time. The PFAS perceived risk of the mothers was associated with many factors that influenced reporting of health issues. The association between PFAS exposure and health outcomes needs further investigation.

Maternal PFOS exposure during rat pregnancy causes hypersensitivity to angiotensin II and attenuation of endothelium-dependent vasodilation in the uterine arteries

Epidemiological studies show a strong association between environmental exposure to perfluorooctane sulfonic acid (PFOS) and preeclampsia and fetal growth restriction; however, the underlying mechanisms are unclear. We tested the hypothesis that gestational PFOS exposure leads to pregnancy complications via alterations in uterine vascular endothelium-independent angiotensin II-related mechanisms and endothelium-derived factors such as nitric oxide. Pregnant Sprague Dawley rats were exposed to PFOS 0.005, 0.05, 0.5, 5, 10, and 50 μg/mL through drinking water from gestational day 4 to 20, and dams with PFOS 50 μg/mL were used to assess mechanisms. PFOS exposure dose-dependently increased maternal blood pressure but decreased fetal weights. Uterine artery blood flow was lower and resistance index was higher in the PFOS dams. In PFOS dams, uterine artery contractile responses to angiotensin II were significantly greater, whereas contractile responses to K+ depolarization and phenylephrine were unaffected. Plasma angiotensin II levels were not significantly different between control and PFOS dams; however, PFOS exposure significantly increased AGTR1 and decreased AGTR2 protein levels in uterine arteries. Endothelium-dependent relaxation response to acetylcholine was significantly reduced with decreased endothelial nitric oxide synthase expression in the uterine arteries of PFOS dams. Left ventricular hypertrophy and fibrosis were observed, along with increased ejection fraction and fractional shortening in PFOS dams. These results suggest that elevated maternal PFOS levels decrease uterine blood flow and increase vascular resistance via heightened angiotensin II-mediated vasoconstriction and impaired endothelium-dependent vasodilation, which provides a molecular mechanism linking elevated maternal PFOS levels with gestational hypertension and fetal growth restriction.

Early-pregnancy plasma per- and polyfluoroalkyl substance (PFAS) concentrations and hypertensive disorders of pregnancy in the Project Viva cohort

BACKGROUND

Hypertensive disorders of pregnancy (HDP), defined here as hypertensive disorders with onset in pregnancy (i.e., gestational hypertension, preeclampsia, and preeclampsia superimposed on chronic hypertension), affect up to 10% of pregnancies in the United States and are associated with substantial maternal and neonatal morbidity and mortality. Per- and polyfluoroalkyl substances (PFAS) are associated with adverse cardiometabolic outcomes during pregnancy, but associations between PFAS and HDP are inconsistent and joint effects of PFAS mixtures have not been evaluated.

METHODS

We studied 1,558 pregnant individuals from the Project Viva cohort, recruited during 1999-2002. We quantified concentrations of eight PFAS in plasma samples (median 9.7 weeks of gestation). Using clinical records, we calculated trimester-specific mean systolic (SBP) and diastolic (DBP) blood pressure and categorized HDP status [no HDP (normotensive & chronic hypertension), gestational hypertension, preeclampsia]. We estimated associations of individual PFAS with HDP using multinomial logistic regression and estimated associations with blood pressure using linear regression. We used Bayesian kernel machine regression (BKMR) and quantile g-computation to assess joint effects of the PFAS mixture on HDP and blood pressure measures.

RESULTS

Four percent of participants developed preeclampsia and 7% developed gestational hypertension. We observed higher odds of gestational hypertension, but not preeclampsia, per doubling of perfluorooctanoate (PFOA) [OR = 1.51 (95% confidence interval: 1.12, 2.03)], perfluorooctane sulfonate (PFOS) [OR = 1.38 (1.04, 1.82)], and perfluorohexane sulfonate [OR = 1.28 (1.06, 1.54)] concentrations. We observed higher mean DBP per doubling of PFOA [2nd trimester (T2): 0.39 mmHg (-0.01, 0.78); 3rd trimester (T3): 0.56 mmHg (0.14, 0.98)] and PFOS [T2: 0.46 mmHg (0.11, 0.82); T3: 0.43 mmHg (0.05, 0.80)]. The PFAS mixture was positively associated with odds of gestational hypertension [75th vs. 50th percentile: OR = 1.14 (95% credible interval:1.03, 1.25), BKMR] and mean DBP [T2 = 0.17 mmHg (-0.06, 0.40); T3 = 0.22 mmHg (-0.03, 0.48), BKMR].

CONCLUSIONS

These findings suggest that exposure to certain PFAS may increase the odds of gestational hypertension during pregnancy, with potential implications for subsequent maternal and child health outcomes.

Retrospective exposure reconstruction using approximate Bayesian computation: A case study on perfluorooctanoic acid and preeclampsia

BACKGROUND

In environmental epidemiology, measurements of toxicants in biological samples are often used as individual exposure assignments. It is common to obtain only one or a few exposure biomarkers per person and use those measurements to represent each person's relevant toxicant exposure for a given health outcome, even though most exposure biomarkers can fluctuate over time. When the timing of the exposure reflected by the biomarker measurement is misaligned with disease development especially if it occurs after the disease outcome, results could be subject to reverse causality or exposure measurement error.

OBJECTIVE

This study aimed to use an approximate Bayesian computation (ABC) method to improve PFOA exposure estimates and characterize the effects of PFOA on preeclampsia in the C8 Studies.

METHODS

Serum PFOA concentrations were measured in blood samples collected during 2005-2006 in West Virginia and Ohio (the C8 Studies), and residential and water use histories and pregnancy outcomes were obtained from self-reports. Our previous results may have been influenced by the choice of methods for characterizing PFOA exposures. Here we use an ABC method to combine measured PFOA serum concentrations and environmentally modeled PFOA concentrations to reconstruct historical PFOA exposures. We also expanded our previous work by assuming more realistic lognormal distributions for key input parameters in the exposure and pharmacokinetic models.

RESULTS

Compared to using fixed values of model parameters and Monte Carlo simulations, ABC produced similar Spearman correlations between estimated and measured serum PFOA concentrations, yet substantially reduced the mean squared error by over 50%. Based on ABC, compared to previous studies, we found a similar adjusted odds ratio (AOR) for the association between PFOA and preeclampsia.

CONCLUSIONS

Bayesian combination of modeled exposure and measured biomarker concentrations can reduce exposure measurement error compared to modeled exposure.

Developmental toxicant exposures and sex-specific effects on epigenetic programming and cardiovascular health across generations

Despite substantial strides in diagnosis and treatment, cardiovascular diseases (CVDs) continue to represent the leading cause of death in the USA and around the world, resulting in significant morbidity and loss of productive years of life. It is increasingly evident that environmental exposures during early development can influence CVD risk across the life course. CVDs exhibit marked sexual dimorphism, but how sex interacts with environmental exposures to affect cardiovascular health is a critical and understudied area of environmental health. Emerging evidence suggests that developmental exposures may have multi- and transgenerational effects on cardiovascular health, with potential sex differences; however, further research in this important area is urgently needed. Lead (Pb), phthalate plasticizers, and perfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants with numerous adverse human health effects. Notably, recent evidence suggests that developmental exposure to each of these toxicants has sex-specific effects on cardiovascular outcomes, but the underlying mechanisms, and their effects on future generations, require further investigation. This review article will highlight the role for the developmental environment in influencing cardiovascular health across generations, with a particular emphasis on sex differences and epigenetic mechanisms. In particular, we will focus on the current evidence for adverse multi and transgenerational effects of developmental exposures to Pb, phthalates, and PFAS and highlight areas where further research is needed.

Exposure to endocrine disrupting chemicals (EDCs) and cardiometabolic indices during pregnancy: The HOME Study

BACKGROUND

Toxicology studies have identified pregnancy as a window of susceptibility for endocrine disrupting chemicals (EDCs) and cardiometabolic indices in women. No study in humans, however, has examined EDC mixtures and cardiometabolic indices during pregnancy.

METHODS

We used the Health Outcomes and Measures of the Environment (HOME) Study to examine whether bisphenol A (BPA), polybrominated diphenyl ethers (PBDEs), per- and polyfluoroalkyl substances (PFAS), and phthalates are associated with blood pressure, glucose, and lipids in 388 pregnant women. We measured PBDEs and PFAS in serum at 16 weeks gestation, while BPA and phthalate metabolites were quantified in urine at 16 and 26 weeks gestation. We used linear regression and Bayesian Kernel Machine Regression (BKMR) to estimate covariate-adjusted associations of individual EDCs and their mixtures with cardiometabolic indices during pregnancy.

RESULTS

A 10-fold increase in BDE-28 was associated with a 13.1 mg/dL increase in glucose (95% Confidence Interval [CI] 2.9, 23.2) in linear regression. The BKMR model also identified BDE-28 as having a positive association with glucose. BDE-28, BDE-47, and BDE-99 were positively associated with total cholesterol in both single- and multi-pollutant models, whereas a suggestive negative association was noted with BDE-153. Mono-n-butyl phthalate (MBP) (β = -7.9 mg/dL, 95% CI -12.9, -3.0) and monobenzyl phthalate (MBzP) (β = -6.3 mg/dL, 95% CI -10.6, -2.0) were both associated with significant decreases in cholesterol in linear regression, but only MBzP was identified as an important contributor in the BKMR model.

CONCLUSION

Overall, we observed positive associations between PBDEs with glucose and cholesterol levels during pregnancy, while negative associations were found between some phthalate biomarkers and cholesterol. No relationship was noted for BPA or PFAS with cardiometabolic indices during pregnancy across both models.

Do perfluoroalkyl substances aggravate the occurrence of obesity-associated glucolipid metabolic disease?

BACKGROUND

Since 2016, more and more studies have been conducted to explore the combination of obesity and perfluoroalkyl substances (PFASs) exposure, and the results indicate that PFASs may be connected with the occurrence of obesity-associated glucolipid metabolic disease (GLMD).

OBJECTIVES

This article summarizes the epidemiological studies on PFASs and obesity-related GLMD, as well as relevant experimental evidence.

RESULTS

(i) Both obesity and PFASs exposure can cause disorder of glucose and lipid metabolism (GLM). (ii) Obesity is a pivotal factor in the high incidence of GLMD induce by PFASs. (iii) PFASs are aggravating the occurrence of obesity-associated GLMD [e.g., diabetes, cardiovascular disease (CVD), and liver disease].

CONCLUSION

The paper fills the gaps among environmental chemistry/epidemiology/toxicology area research. More importantly, PFASs should be taken into account to explain the high-prevalence of obesity-related GLMD.

FUTURE DIRECTION

Three research programs are proposed to explore the synergistic mechanism of PFASs and obesity. In addition, three suggestions are recommended to solve the harm of PFASs pollutants to human beings.

Per and poly-fluoroalkyl substances (PFAS) as a contaminant of emerging concern in surface water: A transboundary review of their occurrences and toxicity effects

Per and poly-fluoroalkyl substances (PFAS) have been recognized as contaminants of emerging concerns by the United States Environmental Protection Agency (US EPA) due to their environmental impact. Several advisory guidelines were proposed worldwide aimed at limiting their occurrences in the aquatic environments, especially for perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). This review paper aims to provide a holistic review in the emerging area of PFAS research by summarizing the spatiotemporal variations in PFAS concentrations in surface water systems globally, highlighting the possible trends of occurrences of PFAS, and presenting potential human health impacts as a result of PFAS exposure through surface water matrices. From the data analysis in this study, occurrences of PFOA and PFOS in many surface water matrices were observed to be several folds higher than the US EPA health advisory level of 70 ng/L for lifetime exposure from drinking water. Direct discharge and atmospheric deposition were identified as primary sources of PFAS in surface water and cryosphere, respectively. While global efforts focused on limiting usages of long-chain PFAS such as PFOS and PFOA, the practices of using short-chain PFAS such as perfluorobutanoic acid (PFBA) and perfluorobutane sulfonic acid (PFBS) and PFAS alternatives increased substantially. These compounds are also potentially associated with adverse impacts on human health, animals and biota.

Maternal Levels of Perfluoroalkyl Substances (PFAS) during Early Pregnancy in Relation to Preeclampsia Subtypes and Biomarkers of Preeclampsia Risk

BACKGROUND

Prenatal exposure to perfluoroalkyl substances (PFAS) has been previously associated with preeclampsia, although findings are mixed with respect to the direction and magnitude of effect. To our knowledge, no studies have examined associations between PFAS and preeclampsia subtypes, which may have distinct etiologies.

OBJECTIVE

We examined associations between PFAS, any preeclampsia diagnosis, and early- and late-onset preeclampsia. In addition, we estimated associations between PFAS and the angiogenic biomarkers soluble fms-like tyrosine kinase-1 (sFLT-1) and placental growth factor (PlGF), which provide an estimate of pro- and anti-angiogenic activity within the placenta.

METHODS

This case-control study (n=75 cases, n=75 controls) was sampled from the LIFECODES birth cohort. Nine legacy PFAS were quantified in maternal plasma from early pregnancy (median= 10 wk) and angiogenic biomarkers were quantified in maternal plasma from four study visits (median= 10, 18, 26, and 35 wk). Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the association between an interquartile range (IQR)-increase in PFAS and preeclampsia outcomes. Linear regression was used to estimate associations between an IQR-increase in PFAS and concentrations of angiogenic biomarkers.

RESULTS

Both perfluorodecanoic acid (OR= 1.64, 95% CI: 1.08, 2.47) and perfluorooctanesulfonic acid (OR= 1.60, 95% CI: 1.06, 2.43) were associated with higher odds of late-onset preeclampsia. Associations tended to be below the null for early-onset preeclampsia, although findings were imprecise. Few associations were noted between PFAS and angiogenic biomarkers.

DISCUSSION

Maternal PFAS concentrations were associated with higher odds of late-onset preeclampsia. Heterogeneity of preeclampsia should be considered in future studies because populations may have different distributions of disease subtypes. https://doi.org/10.1289/EHP9091.

Endocrine-Disrupting Chemical Exposures in Pregnancy: a Sensitive Window for Later-Life Cardiometabolic Health in Women

Purpose of Review

Pregnancy can be seen as a “stress test” with complications predicting later-life cardiovascular disease risk. Here, we review the growing epidemiological literature evaluating environmental endocrine-disrupting chemical (EDC) exposure in pregnancy in relation to two important cardiovascular disease risk factors, hypertensive disorders of pregnancy and maternal obesity.

Recent Findings

Overall, evidence of EDC-maternal cardiometabolic associations was mixed. The most consistent associations were observed for phenols and maternal obesity, as well as for perfluoroalkyl substances (PFASs) with hypertensive disorders. Research on polybrominated flame retardants and maternal cardiometabolic outcomes is limited, but suggestive.

Summary

Although numerous studies evaluated pregnancy outcomes, few evaluated the postpartum period or assessed chemical mixtures. Overall, there is a need to better understand whether pregnancy exposure to these chemicals could contribute to adverse cardiometabolic health outcomes in women, particularly given that cardiovascular disease is the leading cause of death in women.

Understanding the Impact of Perfluorinated Compounds on Cardiovascular Diseases and Their Risk Factors: A Meta-Analysis Study

Perfluorinated compounds (PFCs) are non-biodegradable synthetic chemical compounds that are widely used in manufacturing many household products. Many studies have reported the association between PFCs exposure with the risk of developing cardiovascular diseases (CVDs). However, those reports are still debatable, due to their findings. Thus, this review paper aimed to analyse the association of PFCs compound with CVDs and their risk factors in humans by systematic review and meta-analysis. Google Scholar, PubMed and ScienceDirect were searched for PFCs studies on CVDs and their risk from 2009 until present. The association of PFCs exposure with the prevalence of CVDs and their risk factors were assessed by calculating the quality criteria, odds ratios (ORs), and 95% confidence intervals (CIs). CVDs risk factors were divided into serum lipid profile (main risk factor) and other known risk factors. The meta-analysis was then used to derive a combined OR test for heterogeneity in findings between studies. Twenty-nine articles were included. Our meta-analysis indicated that PFCs exposure could be associated with CVDs (Test for overall effect: z = 2.2, p = 0.02; Test for heterogeneity: I² = 91.6%, CI = 0.92–1.58, p < 0.0001) and their risk factors (Test for overall effect: z = 4.03, p < 0.0001; Test for heterogeneity: I² = 85.8%, CI = 1.00–1.14, p < 0.0001). In serum lipids, total cholesterol levels are frequently reported associated with the exposure of PFCs. Among PFCs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) exposure increased the risk of CVDs than other types of PFCs. Although the risk of PFOA and PFOS were positively associated with CVDs and their risk factors, more observational studies shall be carried out to identify the long-term effects of these contaminants in premature CVDs development in patients.

Biological changes in the pregnancy-postpartum period and subsequent cardiometabolic risk-UPSIDE MOMS: A research protocol

Multiple physiological changes occur in pregnancy as a woman's body adapts to support the growing fetus. These pregnancy-induced changes are essential for fetal growth, but the extent to which they reverse after pregnancy remains in question. For some women, physiological changes persist after pregnancy and may increase long-term cardiometabolic disease risk. The National Institutes of Health-funded study described in this protocol addresses a scientific gap by characterizing weight and biological changes during pregnancy and an extended postpartum period in relation to cardiometabolic risk. We use a longitudinal repeated measures design to prospectively examine maternal health from early pregnancy until 3 years postpartum. The aims are: (1) identify maternal weight profiles in the pregnancy-postpartum period that predict adverse cardiometabolic risk profiles three years postpartum; (2) describe immune, endocrine, and metabolic biomarker profiles in the pregnancy-postpartum period, and determine their associations with cardiometabolic risk; and (3) determine how modifiable postpartum health behaviors (diet, physical activity, breastfeeding, sleep, stress) (a) predict weight and cardiometabolic risk in the postpartum period; and (b) moderate associations between postpartum weight retention and downstream cardiometabolic risk. The proposed sample is 250 women. This study of mothers is conducted in conjunction with the Understanding Pregnancy Signals and Infant Development study, which examines child health outcomes. Biological and behavioral data are collected in each trimester and at 6, 12, 24, and 36 months postpartum. Findings will inform targeted health strategies that promote health and reduce cardiometabolic risk in childbearing women.

Per and polyfluoroalkyl substances scientific literature review: water exposure, impact on human health, and implications for regulatory reform

Among other emerging contaminants in water, per and polyfluoroalkyl substances (PFASs) have garnered international attention from the scientific community on a global scale. Some countries, such as the United States, have found that PFASs are present in humans on a wide scale. Although two PFASs have been widely studied-Perfluorooctanoic acid and Perfluorooctanesulfonic acid-many more PFASs are being created by industry and are either not known, not studied, or both. The objective of this literature review on PFASs is to give an overview of the information available about PFASs related to human exposure. The information from this literature review on the exposure of humans to PFASs through drinking water and the lack of many conventional drinking water treatment systems' ability to remove PFASs (particularly short-chain PFASs) suggests that current regulatory limits are insufficient to adequately protect humans. This is especially true for particularly vulnerable populations such as infants, young children, and developing children (pubescent). The gaps in the current knowledge and in current regulatory approaches could have long-term effects on human health.

Considering environmental exposures to per- and polyfluoroalkyl substances (PFAS) as risk factors for hypertensive disorders of pregnancy

Hypertensive disorders of pregnancy (HDP), including preeclampsia and gestational hypertension, lead to significant maternal morbidity and in some cases, maternal mortality. Environmental toxicants, especially those that disrupt normal placental and endothelial function, are emerging as potential risk factors for HDP. Per- and polyfluoroalkyl substances (PFAS) are a large group of ubiquitous chemicals found in consumer products, the environment, and increasingly in drinking water. PFAS have been associated with a multitude of adverse health effects, including dyslipidemia, hypertension, and more recently, HDP. In this review, we present epidemiological and mechanistic evidence for the link between PFAS and HDP and recommend next steps for research and prevention efforts. To date, epidemiological studies have assessed associations between only ten of the thousands of PFAS and HDP. Positive associations between six PFAS (PFOA, perfluorooctanoic acid; PFOS, perfluorooctane sulfonic acid; PFHxS, perfluorohexane sulfonic acid; PFHpA, perfluoroheptanoic acid; PFBS, perfluorobutanesulfonic acid; and PFNA, perfluoronanoic acid) and risk for HDP have been reported in some, but not all, studies. PFAS disrupt placental and immune function, cause oxidative stress, and disrupt lipid metabolism. These physiological disruptions may be mechanisms through which PFAS can lead to HDP. Overall, limited epidemiological evidence and plausible mechanisms support PFAS as risk factors for HDP. More research is needed in diverse, well-powered cohorts that assess exposures to as many PFAS as possible. Such research should consider not only individual PFAS but also the totality of exposures to PFAS and other environmental chemicals. Pregnant women may be a group that is vulnerable to PFAS exposure, and as such HDP risk should be considered by policymakers setting PFAS exposure limits. In the interim, medical and public health professionals in regions with PFAS contamination could provide short-term solutions in the form of patient-level prevention, increased monitoring, and early intervention for HDP.

Exposure to perfluoroalkyl substances and blood pressure in pregnancy among 1436 women from the Odense Child Cohort

BACKGROUND

Previous studies of association between exposure to poly- and perfluoroalkyl substances (PFAS) and gestational hypertension (GH) and preeclampsia (PE) have shown conflicting results, but most dichotomized outcome and did not study continuous blood pressure (BP) changes.

OBJECTIVES

To study the association between PFAS exposure in early pregnancy and maternal BP trajectories in pregnancy, gestational hypertension and preeclampsia.

METHODS

1436 women were enrolled in the Odense Child Cohort in early pregnancy and had a serum sample drawn, from which perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were measured using LC-MS/MS. Repeated BP measurements through pregnancy and information on PE were obtained from hospital files. Adjusted linear mixed models were used to investigate association between PFAS exposure and BP trajectory. Associations between PFAS and PE and GH were assessed by Cox proportional hazards model.

RESULTS

All women had measurable concentrations of PFAS. In all of many comparisons higher PFAS exposure (apart from PFHxS) was associated with higher systolic (SBP) and diastolic (DBP) blood pressures, although not all were significant, which is unlikely to be due to chance. After adjustment, each doubling in PFOS or PFOA exposure was associated with 0.47 mmHg (95% CI: -0.13; 1.08) and 0.36 mmHg (-0.19; 0.92) higher SBP; and 0.58 mmHg (0.13; 1.04) and 0.37 mmHg (-0.05; 0.79) higher DBP. No clear associations between PFAS exposure and PE or GH were found.

DISCUSSION

The magnitude of the association between PFAS exposure and BP might appear small, statistically non-significant and the possible clinical importance low. However, at a population level this may slightly shift the distribution of BP towards an increased incidence of GH. If BP increases in pregnancy, it may have long-term impact on health not only of the pregnant woman but also of her offspring.

Per- and Polyfluoroalkyl Substance Toxicity and Human Health Review: Current State of Knowledge and Strategies for Informing Future Research

Reports of environmental and human health impacts of per- and polyfluoroalkyl substances (PFAS) have greatly increased in the peer-reviewed literature. The goals of the present review are to assess the state of the science regarding toxicological effects of PFAS and to develop strategies for advancing knowledge on the health effects of this large family of chemicals. Currently, much of the toxicity data available for PFAS are for a handful of chemicals, primarily legacy PFAS such as perfluorooctanoic acid and perfluorooctane sulfonate. Epidemiological studies have revealed associations between exposure to specific PFAS and a variety of health effects, including altered immune and thyroid function, liver disease, lipid and insulin dysregulation, kidney disease, adverse reproductive and developmental outcomes, and cancer. Concordance with experimental animal data exists for many of these effects. However, information on modes of action and adverse outcome pathways must be expanded, and profound differences in PFAS toxicokinetic properties must be considered in understanding differences in responses between the sexes and among species and life stages. With many health effects noted for a relatively few example compounds and hundreds of other PFAS in commerce lacking toxicity data, more contemporary and high-throughput approaches such as read-across, molecular dynamics, and protein modeling are proposed to accelerate the development of toxicity information on emerging and legacy PFAS, individually and as mixtures. In addition, an appropriate degree of precaution, given what is already known from the PFAS examples noted, may be needed to protect human health. Environ Toxicol Chem 2021;40:606-630. © 2020 SETAC.