Per- and Polyfluoroalkyl Substances and Incident Hypertension in Multi-Racial/Ethnic Women: The Study of Women's Health Across the Nation

Perfluoroalkyl/Polyfluoroalkyl Substances: Links to Cardiovascular Disease Risk

Conservative estimates by the World Health Organization suggest that at least a quarter of global cardiovascular diseases are attributable to environmental exposures. Associations between air pollution and cardiovascular risk have garnered the most headlines and are strong, but less attention has been paid to other omnipresent toxicants in our ecosystem. Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are man-made chemicals that are extensively used in industrial and consumer products worldwide and in aqueous film-forming foam utilized in firefighting. As such, our exposure to PFAS is essentially ubiquitous. Given the long half-lives of these degradation-resistant chemicals, virtually, all people are carrying a body burden of PFAS. Health concerns related to PFAS are growing such that the National Academies of Sciences, Engineering and Medicine has recommended standards for clinical follow-up of individuals with high PFAS blood levels, including prioritizing screening for dyslipidemia. The link between PFAS and dyslipidemia has been extensively investigated, and evidence for associations is compelling. However, dyslipidemia is not the only cardiovascular risk factor with which PFAS is associated. Here, we review the epidemiological evidence for links between PFAS of concern identified by the National Academies of Sciences, Engineering and Medicine and risk factors for cardiovascular disease, including overweight/obesity, glucose intolerance, hypertension, dyslipidemia, and hyperuricemia. Moreover, we review the potential connections of PFAS with vascular disease and atherosclerosis. While observational data support associations between the National Academies of Sciences, Engineering and Medicine PFAS and selected cardiac risk factors, additional research is needed to establish causation and better understand how exposure to PFAS leads to the development of these conditions.

The Urban Environment and Cardiometabolic Health

Urban environments contribute substantially to the rising burden of cardiometabolic diseases worldwide. Cities are complex adaptive systems that continually exchange resources, shaping exposures relevant to human health such as air pollution, noise, and chemical exposures. In addition, urban infrastructure and provisioning systems influence multiple domains of health risk, including behaviors, psychological stress, pollution, and nutrition through various pathways (eg, physical inactivity, air pollution, noise, heat stress, food systems, the availability of green space, and contaminant exposures). Beyond cardiometabolic health, city design may also affect climate change through energy and material consumption that share many of the same drivers with cardiometabolic diseases. Integrated spatial planning focusing on developing sustainable compact cities could simultaneously create heart-healthy and environmentally healthy city designs. This article reviews current evidence on the associations between the urban exposome (totality of exposures a person experiences, including environmental, occupational, lifestyle, social, and psychological factors) and cardiometabolic diseases within a systems science framework, and examines urban planning principles (eg, connectivity, density, diversity of land use, destination accessibility, and distance to transit). We highlight critical knowledge gaps regarding built-environment feature thresholds for optimizing cardiometabolic health outcomes. Last, we discuss emerging models and metrics to align urban development with the dual goals of mitigating cardiometabolic diseases while reducing climate change through cross-sector collaboration, governance, and community engagement. This review demonstrates that cities represent crucial settings for implementing policies and interventions to simultaneously tackle the global epidemics of cardiovascular disease and climate change.

Associations of polycyclic aromatic hydrocarbons mixtures with cardiovascular diseases mortality and all-cause mortality and the mediation role of phenotypic ageing: A time-to-event analysis

The associations of polycyclic aromatic hydrocarbons (PAHs) with cardiovascular diseases (CVDs) and all-cause mortality are unclear, especially the joint effects of PAHs exposure. Meanwhile, no studies have examined the effect of phenotypic ageing on the relationship between PAHs and mortality. Therefore, this study aimed to investigate the independent and joint associations between PAHs and CVDs, all-cause mortality, and assess whether phenotypic age acceleration (PhenoAgeAccel) mediate this relationship. We retrospectively collected data of 11,983 adults from the National Health and Nutrition Examination Survey database. Firstly, Cox proportional hazards regression and restricted cubic splines were applied to evaluate the independent association of single PAH on mortality. Further, time-dependent Probit extension of Bayesian Kernel Machine Regression and quantile-based g-computation models were conducted to test the joint effect of PAHs on mortality. Then, difference method was used to calculate the mediation proportion of PhenoAgeAccel in the association between PAHs and mortality. Our results revealed that joint exposure to PAHs showed positive association with CVDs and all-cause mortality. By controlling potential confounders, 1-Hydroxynapthalene (1-NAP) (HR = 1.24, P = 0.035) and 2-Hydroxyfluorene (2-FLU) (HR = 1.25, P < 0.001) showed positive association with CVDs mortality, and they were the top 2 predictors (weight: 0.82 for 1-NAP, 0.14 for 2-FLU) of CVDs mortality. 1-NAP (HR = 1.15, P < 0.001) and 2-FLU (HR = 1.13, P < 0.001) also showed positive association with all-cause mortality, and they were also the top 2 predictors of all-cause mortality (weight: 0.66 for 1-NAP, 0.34 for 2-FLU). PhenoAgeAccel mediated the relationship between 1-NAP, 2-FLU and CVDs, all-cause mortality, with a mediation proportion of 10.00 % to 24.90 % (P < 0.05). Specifically, the components of PhenoAgeAccel including C-reactive protein, lymphocyte percent, white blood cell count, red cell distribution width, and mean cell volume were the main contributors of mediation effects. Our study highlights the hazards of joint exposure of PAHs and the importance of phenotypic ageing on the relationship between PAHs and mortality.

Exposure to per- and polyfluoroalkyl substance and metabolic syndrome: A nationally representative cross-sectional study from NHANES, 2003-2018

Per- and polyfluoroalkyl substances(PFAS) are widespread organic pollutants with endocrine-disrupting effects on human health, but the association of PFAS exposure with metabolic syndrome remains conflicting. National Health and Nutrition Examination Survey(NHANES) program was utilized to evaluate the association of individual PFAS exposure and metabolic disorders and further determined the joint effect of PFAS co-exposures. 13921 participants and five PFAS exposures(PFHxS, MPAH, PFDE, PFNA, and PFUA) were included for analysis. The association between individual PFAS and metabolic syndrome varied in the specific PFAS and the specific metabolic disorder examined. PFHxS was negatively associated with obesity(Q4; OR = 0.75; P < 0.001), but positively associated with hyperlipidemia (Q3; OR = 1.2; P = 0.013). PFUA was negatively associated with obesity (Q4; OR = 0.6; P < 0.001), hyperlipidemia (Q3; OR = 0.85; P = 0.03), and non-alcoholic fatty liver disease (NAFLD, Q4; OR = 0.64; P = 0.015), but positively associated with hyperglycemia(Q3; OR = 1.27; P = 0.004). Furthermore, PFAS co-exposures were negatively associated with obesity(OR = 0.63; P < 0.001) and NAFLD(OR = 0.85; P = 0.021), and positively associated with hyperlipidemia(OR = 1.05; P = 0.022), but not significantly associated with hyperglycemia or hypertension. Overall, there was a negative association between PFAS co-exposures and metabolic severity score(β = -0.15; P < 0.001). Subgroup analysis stratified by gender and obesity consistently showed the negative association of PFAS co-exposures with metabolic severity score, and the positive association with hyperlipidemia. However, subgroup analysis showed a negative association with NAFLD in females but not in males, and a negative association with hyperglycemia in the obesity group, but not in the non-obesity group. Collectively, our study showed a negative association of PFAS co-exposures with metabolic syndrome severity score, but did not support a consistent association between PFAS co-exposures and individual components of metabolic syndrome. Additionally, there were gender-specific as well as BMI-specific differences in these associations. Further studies are needed to rule out the reverse causality and clarify the relationship of PFAS co-exposures with the specific metabolic disorder.

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.

The Association of Hypertension with Perfluoroalkyl and Polyfluoroalkyl Substances

Perfluoroalkyl and polyfluoroalkyl substance (PFAS) is a large group of fluorinated synthetic chemicals, e.g., perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS), perfluorodecanoic acid (PFDA), and perfluorononanoic acid (PFNA). Many epidemiological studies have found that PFAS exposure is associated with hypertension risk, but others possess a different opinion. Overall, the relationship between PFASs and hypertension risk remains controversial. We sought to conduct a systematic review and meta-analysis to clarify the association between PFAS exposure and human risk of hypertension.We conducted a meta-analysis based on population-involving studies published from 1975 to 2023, which we collected from Web of Science, PubMed, and Embase databases. The odds ratio (OR) and standardized mean difference (SMD), with their 95% confidence interval (CI), were used to assess the risk of hypertension with PFAS exposure. The statistical heterogeneity among studies was assessed with the Q-test and I2 statistics. Research publications related to our meta-analysis topic were systematically reviewed.Fourteen studies involving 71,663 participants, in which 26,281 suffered hypertension, met the inclusion criteria. Our analyses suggest that exposure to general PFAS (OR = 1.09, 95% CI = 1.04-1.14) or PFOS (OR = 1.17, 95% CI = 1.05-1.30) is associated with hypertension risk. Specifically, elevated levels of general PFAS (SMD = 0.25, 95% CI = 0.08-0.42), PFHxS (SMD = 0.17, 95% CI = 0.07-0.27), and PFDA (SMD = 0.08, 95% CI = 0.02-0.13) are associated with a high risk of hypertension.Our meta-analysis indicates that PFAS exposure is a risk factor for hypertension, and increased hypertension risk is associated with higher PFAS levels. Further study may eventually provide a better and more comprehensive elucidation of the potential mechanism of this association.

Perfluoroalkyl substances (PFAS) and lead (Pb) as "cardiovascular disruptors" in 9-11-year-old children living in Syracuse, New York, United States

OBJECTIVE

Per- and polyfluoro-alkyl substances (PFAS) and lead (Pb) are ubiquitous environmental toxicants with apparent impact on cardiovascular disease (CVD) risk. As one possible mechanism for this increased risk, we have previously demonstrated an association between Pb exposure and heightened cardiovascular reactivity to acute psychological stress, a CVD risk factor. The present study expands this approach and considers both PFAS and Pb exposures (and the possible interaction).

METHODS

We assessed 14 serum PFAS and whole blood Pb concentrations in a sample of 9-11 year-old children (N = 291; 43.2% White, 56.8% Black; 53.5% female). We measured cardiovascular functioning at rest and during psychological stress as well as multiple indicators of subclinical CVD including resting blood pressure (BP), carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), and left ventricular mass (LVM). Data analysis included general linear modeling as well as a non-parametric approach to study metal mixtures, specifically Bayesian Kernel Machine Regression (BKMR).

RESULTS

Significant interactions between different PFAS and with Pb suggest the importance of considering toxicant mixtures when assessing potential disruption of the cardiovascular system. The pattern of findings suggests that greater "vascular reactivity" (elevated BP and vascular resistance during acute psychological stress) was associated with higher concentrations of perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), and Pb, but only when perfluorooctanoic acid (PFOA) was concurrently elevated. With respect to subclinical outcomes, increasing perfluorodecanoic acid (PFDA) was associated with greater cIMT (β = 0.21, p = 0.010).

CONCLUSION

To our knowledge this is the first study to consider how PFAS exposures might affect cardiovascular functioning and subclinical disease. Although a complex pattern of associations emerged, it does appear that PFAS and Pb can be classified as "cardiovascular disruptors" in children. Further research is needed to replicate these novel findings and determine whether these disruptions produce future cardiovascular disease.

Endocrine disruptors and arterial hypertension: A developing story

Endocrine disrupting Chemicals (EDCs) are substances that interfere with hormones by several mechanisms including receptor activation or antagonism, changes in gene and protein expression, modification of signal transduction, and/or epigenetic modifications in hormone-producing cells. A survey conducted by the European Union in a Northern Italian region led to the discovery of a large environmental contamination of drinking water by perfluoroalkyl substances (PFAS). As the exposed population showed a high prevalence of arterial hypertension and cardiovascular disease, we decided to investigate if PFAS could enhance the biosynthesis of aldosterone. To this aim, we exposed human adrenocortical carcinoma HAC15 cells to PFAS and found that PFAS markedly increased aldosterone synthase (CYP11B2) gene expression and aldosterone secretion. Moreover, we found that they promoted reactive oxygen species (ROS) production in mitochondria, the organelles where aldosterone biosynthesis takes place. PFAS also enhanced the effects of the aldosterone secretagogue angiotensin II (Ang II) on CYP11B2 gene expression and aldosterone secretion. We also found that not only PFAS but also polychlorinated biphenyl 126 (PCB126), a chemical compound belonging to a different category of EDCs, can increase CYP11B2 gene expression and aldosterone secretion in adrenocortical cells. This novel information needs to be considered in the context of a widespread exposure to the most common EDC, that is excess Na+ intake, whose detrimental effects on human health occur in the setting of aldosterone production exceeding the physiological needs and lead to high blood pressure, congestion, and cardiovascular and renal damage.

Decreased levels of perfluoroalkyl substances in patients receiving hemodialysis treatment

Perfluoroalkyl substances (PFAS) have been reported to be harmful to multiple organs in the human body. Based on a previous study suggesting that hemodialysis (HD) may be a means of eliminating PFAS from the human body, we aimed to compare the serum PFAS concentrations of patients undergoing regular HD, patients with chronic kidney disease (CKD) and controls. Additionally, we also investigated the correlation between PFAS and biochemical data, as well as concurrent comorbidities. We recruited 301 participants who had been on maintenance dialysis for >90 days, 20 participants with stage 5 non-dialysis CKD, and 55 control participants who did not have a diagnosis of kidney disease, with a mean creatinine level of 0.77 mg/dl. Eight different PFAS, namely perfluorooctanoic acid (PFOA), total and linear perfluorooctanesulfonic acid (PFOS), perfluoroheptanoic acid (PFHpA), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA), were measured using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Spearman correlation and multivariable linear regression with 5 % false discovery rate were used to evaluate the relationships between PFAS and clinical parameters in HD patients and controls. Circulating concentrations of seven PFAS, including total and linear PFOS (T-PFOS and L-PFOS) PFDA, PFNA, PFHxS, PFOA, and PFUnDA, were significantly lower in the HD group compared to the CKD and control group. For the interplay between biochemical data and PFAS, all of the studied PFAS were positively correlated with aspartate aminotransferase, alanine aminotransferase, glucose, blood urea nitrogen, ferritin, and vitamin D in the controls, while in HD patients, the PFAS were all positively correlated with albumin, uric acid, iron, and vitamin D. These findings may offer valuable insights for future studies seeking to eliminate PFAS.

Advanced electrocatalytic redox processes for environmental remediation of halogenated organic water pollutants

Halogenated organic compounds are widespread, and decades of heavy use have resulted in global bioaccumulation and contamination of the environment, including water sources. Here, we introduce the most common halogenated organic water pollutants, their classification by type of halogen (fluorine, chlorine, or bromine), important policies and regulations, main applications, and environmental and human health risks. Remediation techniques are outlined with particular emphasis on carbon-halogen bond strengths. Aqueous advanced redox processes are discussed, highlighting mechanistic details, including electrochemical oxidations and reductions of the water-oxygen system, and thermodynamic potentials, protonation states, and lifetimes of radicals and reactive oxygen species in aqueous electrolytes at different pH conditions. The state of the art of aqueous advanced redox processes for brominated, chlorinated, and fluorinated organic compounds is presented, along with reported mechanisms for aqueous destruction of select PFAS (per- and polyfluoroalkyl substances). Future research directions for aqueous electrocatalytic destruction of organohalogens are identified, emphasizing the crucial need for developing a quantitative mechanistic understanding of degradation pathways, the improvement of analytical detection methods for organohalogens and transient species during advanced redox processes, and the development of new catalysts and processes that are globally scalable.

Exposure characteristics of legacy and novel per- and polyfluoroalkyl substances in blood and association with hypertension among low-exposure population

The exposure characteristics of per- and polyfluoroalkyl substances (PFAS) in blood and their associations with hypertension have been well investigated in high-exposure populations, yet limited information is available concerning low-exposure populations. We conducted a cross-sectional study in a low-exposure population in China. A total of 394 females, including 162 with hypertension, were recruited and 30 PFAS were measured in whole blood samples. General linear model, generalized additive model, and logistic model were used to identify the associations with hypertension. Additionally, a Bayesian kernel machine regression model was conducted to test the mixture effects. Fourteen PFAS, including two novel species, 6:2 and 8:2 chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), were detected, among which PFOS predominated with the highest median level of 1.47 ng/mL. The median levels of individual PFAS were, however, below the 25th, and even the 5th percentile of previous reports, except for PFHxA, which was above the 50th percentile (median of 0.10 ng/mL). After adjusting for covariates, PFHxA showed a positive association with hypertension (OR=1.54, 95% CI: 1.25, 1.89), while 6:2 Cl-PFESA showed a negative association (OR=0.73, 95% CI: 0.56, 0.95). PFAS didn't show significant mixture effects. We proposed that PFHxA may contribute to hypertension and 6:2 Cl-PFESA may have a hormesis effect.

Association of per- and polyfluoroalkyl substances with hepatic steatosis and metabolic dysfunction-associated fatty liver disease among patients with acute coronary syndrome

Etiology of hepatic steatosis and metabolic dysfunction-associated fatty liver disease (MAFLD) among acute coronary syndrome (ACS) remains unclear. Existing studies suggested the potential role of per- and polyfluoroalkyl substances (PFAS) in comorbidity of hepatic steatosis among ACS patients. Therefore, we conducted a cross-sectional study based on the ACS inpatients to assess the associations of plasma PFAS congeners and mixtures with hepatic steatosis and MAFLD. This study included 546 newly diagnosed ACS patients. Twelve PFAS were quantified using ultra-high-performance liquid chromatography-tandem mass spectrometry. Hepatic steatosis was defined by hepatic steatosis index (HSI). MAFLD was defined as the combination of hepatic steatosis based on the risk factor calculation with metabolic abnormalities. Generalized linear model was used to examine the associations of PFAS congeners with HSI and MAFLD. Adaptive elastic net (AENET) was further used for PFAS congeners selection. Mixture effects were also assessed with Bayesian kernel machine regression model (BKMR). Congeners analysis observed significant greater percent change of HSI for each doubling in PFOS (1.82%, 95% CI: 0.87%, 2.77%), PFHxS (1.17%, 95% CI: 0.46%, 1.89%) and total PFAS (1.84%, 95% CI: 0.56%, 3.14%). Moreover, each doubling in PFOS (OR=1.42, 95% CI: 1.13, 1.81), PFHxS (OR=1.31, 95% CI: 1.09, 1.59) and total PFAS (OR=1.43, 95% CI: 1.06, 1.94) was associated with increased risk of MAFLD. In AENET regression, only PFOS presented significant positive associations with HSI. Mixture analysis indicated significant positive associations between PFAS mixtures and HSI. This is the first study to demonstrate associations of PFAS congeners and mixtures with hepatic steatosis and MAFLD among ACS patients, which provides hypothesis into the mechanisms behind comorbidity of hepatic steatosis among ACS patients, as well as tertiary prevention of ACS.

Prenatal and Childhood Per- and Polyfluoroalkyl Substance (PFAS) Exposures and Blood Pressure Trajectories From Birth to Late Adolescence in a Prospective US Prebirth Cohort

Background Evidence is limited regarding the associations of prenatal and childhood per- and polyfluoroalkyl substance (PFAS) exposures with blood pressure (BP) trajectories in children. Methods and Results Participants are from Project Viva, a prospective prebirth cohort in eastern Massachusetts. We measured PFAS in early-pregnancy maternal (median, 9.6 weeks) and midchildhood (median, 7.7 years) plasma samples. We conducted standardized BP measurements at 6 research visits: birth, infancy (median, 6.3 months), early childhood (median, 3.2 years), midchildhood (median, 7.7 years), early adolescence (median, 12.9 years), and late adolescence (median, 17.5 years). We used linear regression to examine associations of individual PFASs with BP at each visit, linear spline mixed-effects regression to model BP trajectories, and a mixture approach to estimate PFAS exposure burden. We included 9036 BP measures from 1506 participants. We observed associations between particular individual prenatal PFASs and child BP at specific time points, for example, prenatal 2-(N-ethyl-perfluorooctane sulfonamido) acetate (EtFOSAA) and 2-(N-methyl-perfluorooctane sulfonamido) acetate (MeFOSAA) with higher systolic BP at birth; prenatal perfluorooctane sulfonate (PFOS) and EtFOSAA with lower diastolic BP in infancy; and prenatal PFOS, perfluorooctanoate (PFOA), and EtFOSAA with higher systolic BP at midchildhood. No prenatal or childhood PFAS was consistently associated with BP across all visits. Diastolic BP trajectories from 0 to 20 years differed slightly by prenatal PFOA, perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA) (P values 0.01-0.09). Diastolic BP trajectories from 6 to 20 years differed slightly by midchildhood PFHxS and MeFOSAA (P-values 0.03-0.08). Prenatal or childhood PFAS mixture burden scores were not associated with BP. Conclusions We found associations of prenatal and childhood PFAS exposures with BP at specific time points between birth and late adolescence but no consistent associations across all time points or PFAS types.

Exposure to perfluoroalkyl and polyfluoroalkyl substances and risk of stroke in adults: a meta-analysis

INTRODUCTION

Evidence of the adverse metabolic health effects of perfluoroalkyl and polyfluoroalkyl substances (PFAS) is increasing. However, the impact of PFAS on cardiovascular diseases remains controversial. This meta-analysis aimed to analyze the impact of PFAS on the stroke risk.

CONTENT

Databases were searched for studies published up to November 1, 2022, which report the association between stroke and exposure to at least one of four main PFAS (perfluorooctanoic acid [PFOA], perfluorooctanesulfonic acid [PFOS], perfluorononanoic acid [PFNA], and perfluorohexane sulfonic acid [PFHxS]). Data extraction and quality assessment were performed according to the Newcastle-Ottawa scale.

SUMMARY AND OUTLOOK

Four studies were included in this systematic review. Multivariate adjusted odds ratios (ORs) for incident stroke per 1-log unit increment in each serum PFAS were combined in the meta-analysis. The risk of development of stroke was not significantly associated with PFOA, PFOS, or PFNA exposure (PFOA: pooled odds ratio [OR]=1.001, 95 % confidence interval [CI]=0.975-1.028, p=0.934; PFOS: pooled OR=0.994, 95 % CI=0.972-1.017, p=0.601; PFNA: pooled OR=1.016, 95 % CI=0.920-1.123, p=0.752), whereas a moderately lower risk was associated with PFHxS exposure without statistical significance (pooled OR=0.953, 95 % CI=0.908-1.001, p=0.054). PFOA, PFOS, and PFNA exposure showed a neutral association, while PFHxS showed a possible inverse association with the risk of stroke. Therefore, this finding should be interpreted with caution. Further prospective observational studies with PFAS mixture analyses are warranted.

Association between per- and polyfluoroalkyl substances and risk of hypertension: a systematic review and meta-analysis

Background

Existing evidence indicates that exposure to per- and polyfluoroalkyl substances (PFASs) may increase the risk of hypertension, but the findings are inconsistent. Therefore, we aimed to explore the relationship between PFASs and hypertension through this systematic review and meta-analysis.

Methods

We searched PubMed, Embase, and the Web of Science databases for articles published in English that examined the relationship between PFASs and hypertension before 13 August 2022. The random effects model was used to aggregate the evaluation using Stata 15.0 for Windows. We also conducted subgroup analyses by region and hypertension definition. In addition, a sensitivity analysis was carried out to determine the robustness of the findings.

Results

The meta-analysis comprised 15 studies in total with 69,949 individuals. The risk of hypertension was substantially and positively correlated with exposure to perfluorooctane sulfonate (PFOS) (OR = 1.31, 95% CI: 1.14, 1.51), perfluorooctanoic acid (PFOA) (OR = 1.16, 95% CI: 1.07, 1.26), and perfluorohexane sulfonate (PFHxS) (OR = 1.04, 95% CI: 1.00, 1.09). However, perfluorononanoic acid (PFNA) exposure and hypertension were not significantly associated (OR = 1.08, 95% CI: 0.99, 1.17).

Conclusion

We evaluated the link between PFASs exposure and hypertension and discovered that higher levels of PFOS, PFOA, and PFHxS were correlated with an increased risk of hypertension. However, further high-quality population-based and pathophysiological investigations are required to shed light on the possible mechanism and demonstrate causation because of the considerable variability.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ PROSPERO, registration number: CRD 42022358142.

Individual and joint associations of long-term exposure to air pollutants and cardiopulmonary mortality: a 22-year cohort study in Northern China

Background

Evidence on the associations between long-term exposure to multiple air pollutants and cardiopulmonary mortality is limited, especially for developing regions with higher pollutant levels. We aimed to characterise the individual and joint (multi-pollutant) associations of long-term exposure to air pollutants with cardiopulmonary mortality, and to identify air pollutant that primarily contributes to the mortality risk.

Methods

We followed 37,442 participants with a mean age of 43.5 years in four cities in northern China (Tianjin, Shenyang, Taiyuan, and Rizhao) from January 1998 to December 2019. Annual particulate matter (PM) with diameters ≤2.5 μm (PM2.5), ≤10 μm (PM10), sulfur dioxide (SO2) and nitrogen dioxide (NO2) were estimated using daily average values from satellite-derived machine learning models and monitoring stations. Time-varying Cox proportional hazards model was used to evaluate the individual association between air pollutants and mortality from non-accidental causes, cardiovascular diseases (CVDs), non-malignant respiratory diseases (RDs) and lung cancer, accounting for demographic and socioeconomic factors. Effect modifications by age, sex, income and education level were also examined. Quantile-based g-Computation integrated with time-to-event data was additionally applied to evaluate the co-effects and the relative weight of contributions for air pollutants.

Findings

During 785,807 person-years of follow-up, 5812 (15.5%) died from non-accidental causes, among which 2932 (7.8%) were from all CVDs, 479 (1.3%) from non-malignant RDs, and 552 (1.4%) from lung cancer. Long-term exposure to PM10 (mean [baseline]: 136.5 μg/m3), PM2.5 (mean [baseline]: 70.2 μg/m3), SO2 (mean [baseline]: 113.0 μg/m3) and NO2 (mean [baseline]: 39.2 μg/m3) were adversely and consistently associated with all mortality outcomes. A 10 μg/m3 increase in PM2.5 was associated with higher mortality from non-accidental causes (hazard ratio 1.20; 95% confidence interval 1.17-1.23), CVDs (1.23; 1.19-1.28), non-malignant RDs (1.37; 1.25-1.49) and lung cancer (1.14; 1.05-1.23). A monotonically increasing curve with linear or supra-linear shape with no evidence of a threshold was observed for the exposure-response relationship of mortality with individual or joint exposure to air pollutants. PM2.5 consistently contributed most to the elevated mortality risks related to air pollutant mixture, followed by SO2 or PM10.

Interpretation

There was a strong and positive association of long-term individual and joint exposure to PM10, PM2.5, SO2, and NO2 with mortalities from non-accidental causes, CVDs, non-malignant RDs and lung cancer in high-exposure settings, with PM2.5 potentially being the main contributor. The shapes of associations were consistent with a linear or supra-linear exposure-response relationship, with no lower threshold observed within the range of concentrations in this study.

Funding

National Key Research and Development Program of China, the China Scholarship Council, the National Natural Science Foundation of China, Natural Science Foundation of Guangdong Province.

Investigating Three Classification Methods for Per/Poly-Fluoroalkyl Substance (PFAS) Exposure from Electronic Health Records And Potential for Bias

Per-/poly-fluoroalkyl substances (PFAS) are a group of manmade compounds with known human toxicity and evidence of contamination in drinking water throughout the US. We augmented our electronic health record data with geospatial information to classify PFAS exposure for our patients living in New Jersey. We explored the utility of three different methods for classifying PFAS exposure that are popularly used in the literature, resulting in different boundary types: public water supplier service area boundary, municipality, and ZIP code. We also explored the intersection of the three boundaries. To study the potential for bias, we investigated known PFAS exposure-disease associations, specifically hypertension, thyroid disease and parathyroid disease. We found that both the significance of the associations and the effect size varied by the method for classifying PFAS exposure. This has important implications in knowledge discovery and also environmental justice as across cohorts, we found a larger proportion of Black/African-American patients PFAS-exposed.

The role of exposure to per- and polyfluoroalkyl substances in racial/ethnic disparities in hypertension: Results from the study of Women's health across the nation

BACKGROUND

Racial/ethnic disparities in hypertension are a pressing public health problem. The contribution of environmental pollutants including PFAS have not been explored, even though certain PFAS are higher in Black population and have been associated with hypertension.

OBJECTIVES

We examined the extent to which racial/ethnic disparities in incident hypertension are explained by racial/ethnic differences in serum PFAS concentrations.

METHODS

We included 1058 hypertension-free midlife women with serum PFAS concentrations in 1999-2000 from the multi-racial/ethnic Study of Women's Health Across the Nation with approximately annual follow-up visits through 2017. Causal mediation analysis was conducted using accelerated failure time models. Quantile-based g-computation was used to evaluate the joint effects of PFAS mixtures.

RESULTS

During 11,722 person-years of follow-up, 470 participants developed incident hypertension (40.1 cases per 1000 person-years). Black participants had higher risks of developing hypertension (relative survival: 0.58, 95% CI: 0.45-0.76) compared with White participants, which suggests racial/ethnic disparities in the timing of hypertension onset. The percent of this difference in timing that was mediated by PFAS was 8.2% (95% CI: 0.7-15.3) for PFOS, 6.9% (95% CI: 0.2-13.8) for EtFOSAA, 12.7% (95% CI: 1.4-22.6) for MeFOSAA, and 19.1% (95% CI: 4.2, 29.0) for PFAS mixtures. The percentage of the disparities in hypertension between Black versus White women that could have been eliminated if everyone's PFAS concentrations were dropped to the 10th percentiles observed in this population was 10.2% (95% CI: 0.9-18.6) for PFOS, 7.5% (95% CI: 0.2-14.9) for EtFOSAA, and 17.5% (95% CI: 2.1-29.8) for MeFOSAA.

CONCLUSIONS

These findings suggest differences in PFAS exposure may be an unrecognized modifiable risk factor that partially accounts for racial/ethnic disparities in timing of hypertension onset among midlife women. The study calls for public policies aimed at reducing PFAS exposures that could contribute to reductions in racial/ethnic disparities in hypertension.

The relationship between perfluoroalkyl substances and hypertension: A systematic review and meta-analysis

Hypertension is an important risk factor for cardiovascular diseases (CVDs) and a leading cause of premature death. Epidemiological studies have found that perfluoroalkyl substances (PFASs) are associated with hypertension. However, the correlation between PFASs and hypertension has not been systematically reported. Based on evidence from population epidemiological surveys, we conducted a meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to assess the correlation between PFASs exposure and hypertension. In this study, three databases of PubMed, Web of science, Embase were searched and 13 literatures with 81,096 participants were included. Literature heterogeneity was evaluated by I² statistic, and the random effect model (I² > 50%) and fixed effect model (I² < 50%) were used to combine the studies in meta-analysis. The results showed that PFNA (OR = 1.11, 95% CI: 1.04-1.19), PFOA (OR = 1.12, 95% CI: 1.02-1.23), PFOS (OR = 1.19, 95% CI: 1.06-1.34) and PFHxS (OR = 1.03, 95% CI: 1.00-1.06) were significantly associated with hypertension, while other types of PFASs (∑PFAS, PFDA, PFUnDA) had no statistical significance. In addition, PFNA (OR = 1.12, 95% CI: 1.03-1.22), PFOA (OR = 1.12, 95% CI: 1.01-1.25) and PFOS (OR = 1.12, 95% CI: 1.00-1.25) exposure were positively correlated with the risk of hypertension in men, but not in women. Our study reveals that PFASs are risk factors for hypertension, with notable gender differences observed in PFASs-exposed populations. Specifically, males exposed to PFNA, PFOA, and PFOS exhibit a higher risk of hypertension compared to females. However, further investigations are needed to delve into the precise mechanism through which PFASs contribute to the development of hypertension.

Aldosterone Biosynthesis Is Potently Stimulated by Perfluoroalkyl Acids: A Link between Common Environmental Pollutants and Arterial Hypertension

The large environmental contamination of drinking water by perfluoroalkyl substances (PFAS) markedly increased the plasma levels of pentadecafluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in a Northern Italy population with a high prevalence of arterial hypertension and cardiovascular disease. As the link between PFAS and arterial hypertension is unknown, we investigated if they enhance the biosynthesis of the well-known pressor hormone aldosterone. We found that PFAS increased aldosterone synthase (CYP11B2) gene expression by three-fold and doubled aldosterone secretion and cell and mitochondria reactive oxygen species (ROS) production over controls (p < 0.01 for all) in human adrenocortical carcinoma cells HAC15. They also enhanced the effects of Ang II on CYP11B2 mRNA and aldosterone secretion (p < 0.01 for all). Moreover, when added 1 h before, the ROS scavenger tempol abolished the effect of PFAS on CYP11B2 gene expression. These results indicate that at concentrations mimicking those found in human plasma of exposed individuals, PFAS are potent disruptors of human adrenocortical cell function, and might act as causative factors of human arterial hypertension via increased aldosterone production.

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.

Phthalate exposure is associated with more rapid body fat gain in midlife women: The Study of Women's Health Across the Nation (SWAN) Multi-Pollutant Study

Obesity is a major threat to health, but the etiology of obesity is incompletely understood. Phthalates, synthetic chemicals ubiquitous in the environment, are suspected to have obesogenic effects, but the relationship of phthalates and obesity in humans remains uncertain. We examined whether phthalate exposure was associated with body fat gain in midlife women. We analyzed data from 1369 women in the Study of Women's Health Across the Nation Multi-Pollutant Study. Eleven phthalate metabolites measured in spot urine samples at baseline (1999/2000) were standardized with covariate-adjusted creatinine. Body weight (BW), fat mass (FM) from dual-energy X-ray absorptiometry (DXA), and body fat percentage (BF%) from DXA were measured near-annually until 2016/2017. For each metabolite, linear mixed effects models with time and log2(metabolite) interactions were examined, adjusting for demographic, lifestyle, and menopause-related factors. Analyses were conducted overall and stratified by baseline obesity status. As sensitivity analyses, all analyses were repeated using a second set of metabolites measured in 2002/2003. Higher levels of all metabolites except mono-carboxy-isononyl phthalate were associated with faster increases in BF%. Per doubling of metabolite concentrations, differences in five-year BF% change ranged from 0.03 percentage point (ppt) (95% confidence interval (CI): -0.03, 0.09) for mono-isobutyl phthalate to 0.09 ppt (95% CI: 0.02, 0.16) for mono(3-carboxypropyl) phthalate. Results were similar for FM change, but associations with BW change were mostly null. In stratified analyses by baseline obesity status, positive associations were strongest in women who were normal/underweight at baseline. When metabolites from 2002/2003 were used as exposures, most associations were attenuated and not statistically significant, but they remained positive for normal/underweight women. In conclusion, phthalate metabolites were associated with more rapid body fat gain in midlife women, but our results need confirmation given attenuation of estimates in the sensitivity analyses.