Exposure to multiple metals and prevalence for preeclampsia in Taiyuan, China

A study on the mediating role of serum hormones in the effects of heavy metals on preeclampsia

Exposure to environmental heavy metals may pose a risk factor for developing preeclampsia (PE) modified through intervention. This case-control study aimed to investigate the association between serum heavy metal concentrations and PE in pregnant women and whether hormones served as mediating factors in the impact of heavy metals on PE. From October 2020 to 2022, 160 patients with PE and 160 pregnant women with normal deliveries were recruited at Dongguan Songshan Lake Central Hospital. Serum concentrations of manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), β-human chorionic gonadotropin (β-hCG), progesterone (P), estradiol (E2), testosterone (T), cortisol (Cort), and cortisone (Cor) were measured. Logistic, restricted cubic splines, weighted quantile sum and multivariate linear regression models were employed to account for different aspects and explore the relationships among heavy metals, hormones, and PE. Mediation model analysis was performed to assess the role of hormones in mediation. The median concentrations of Mn, E2, and Cort were lower in the PE group than in the control group. The median concentrations of Cu, Zn, β-hCG, and T were higher in the PE than in the control. Mn, E2, and Cort showed negative associations with PE, while Cu, Zn, β-hCG, and T demonstrated positive associations, as determined through logistic regression. Mn, Cu, and Zn displayed linear dose-response relationships with PE. Zn and Cu had high weights in the positive association model of mixed heavy metal exposure with PE. The mediation analysis revealed that serum E2, P, T, Cort, and Cort/Cor might be potential mediators of the association between heavy metals (Mn, Cu, and Zn) and PE.

Environmental exposure to metal(loid)s and hypertensive disorders of pregnancy: A systematic review

BACKGROUND

Environmental exposure to metal(loid)s has been associated with adverse effects on human health, but the systemic repercussion of these elements on the development of hypertensive disorders of pregnancy (HDP) is still poorly understood.

OBJECTIVE

To summarize evidence published about the influence of environmental exposure to aluminum, arsenic, barium, cadmium, lead, strontium and mercury on the development of HDP.

METHODS

We conducted a systematic literature review according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The search strategy was validated by the Peer Review of Electronic Search Strategies. We searched for articles published up to February 2023 in seven databases without language restriction. Two researchers conducted the steps for selection, data extraction and evaluation of the methodological quality of the instruments for epidemiological studies of the Joanna Briggs Institute. Any disagreements were resolved by a third researcher.

RESULTS

We obtained 5076 records, of which 37 articles met the inclusion criteria moderate to high methodological quality. Single exposure to metal(loid)s was predominant, and the leading biological matrix analyzed to detect the concentrations from exposure was maternal blood. Lead was the metal investigated the most, and had the largest number of studies showing positive association with HDP. In relation to the other metal(loid)s, higher levels were found in women with HDP in comparison with healthy women, but the finding of a cause-effect relationship was inconsistent.

CONCLUSIONS

Although we found evidence of harmful effects of the metal(loid)s studied on human health, the results were inconclusive with regard to HDP. Longitudinal studies that consider prospective investigation, adjustment of confounding factors and the interference of other contaminants in the exacerbation of oxidative stress in women from the preconception phase to the puerperal period should be encouraged.

The Relationship Between Heavy Metals and Missed Abortion: Using Mediation of Serum Hormones

Accumulating evidence suggests that heavy metal exposure may have adverse effects on the fetal development. Furthermore, disruption of serum hormone homeostasis can result in the adverse pregnancy outcomes. Therefore, this study aimed to investigate the potential association between heavy metals and missed abortion, with a focus on whether serum hormones mediate this relationship. The concentrations of heavy metals and hormones in serum were measured in this case-control study. Statistical models including, logistic regression model, principal component analysis (PCA), and weighted quantile sum (WQS) regression model were employed to examine the relationship between heavy metals, serum hormones, and missed abortion. Furthermore, the mediation analysis was performed to assess the role of serum hormones as potential mediators in this relationship. This study revealed significant associations between heavy metal exposure and missed abortion. Notable, the WQS index weight, which was mainly influenced by copper (Cu) and zine (Zn), is associated with missed abortion. Moreover, heavy metals including manganese (Mn), nickel (Ni), Zn, arsenic (As), Cu, cadmium (Cd), and lead (Pb) were found to be associated with serum levels of β-human chorionic gonadotropin (β-hCG), progesterone (P), estradiol (E2), and lactogen (HPL). In addition, the mediation analysis indicated that β-hCG explained a portion of the association (ranging from 18.77 to 43.51%) of between Mn, Ni, Zn, and As exposure and missed abortion. Serum P levels explained 17.93 to 51.70% of the association between Ni, Cu, and As exposure and missed abortion. Serum E2 levels played a significant mediating role, explaining a portion of the association (ranging from 22.14 to 73.60%) between Mn, Ni, Cu, As, Cd, and Pb exposure and missed abortion. Our results suggested that β-hCG, P, and E2 are one of the potential mediators in the complex relationship between heavy metals exposure and missed abortion. These results highlight the importance of considering both heavy metal exposure and serum hormone levels in understanding the etiology of missed abortion.

First trimester prenatal metal mixtures, vitamins, and hypertensive disorders of pregnancy in the project viva cohort

BACKGROUND

Hypertensive disorders of pregnancy (HDP) such as preeclampsia and gestational hypertension are major contributors to maternal and child morbidity and mortality. Previous studies have reported associations with selected metals and vitamins but are limited in sample size and non-prospective study designs. We evaluated prospective associations of metal mixtures with HDP and tested interactions by vitamins.

STUDY DESIGN

We measured first trimester (median = 10.1 weeks) concentrations of essential (copper, magnesium, manganese, selenium, zinc) and nonessential (arsenic, barium, cadmium, cesium, mercury, lead) metals in red blood cells (n = 1,386) and vitamins (B12 and folate) in plasma (n = 924) in Project Viva, a pre-birth US cohort. We collected diagnosis of HDP by reviewing medical records. We used multinomial logistic regression and Bayesian Kernel Machine Regression to estimate individual and joint associations of metals with HDP and interactions by vitamins, after adjusting for key covariates.

RESULTS

The majority of participants were non-Hispanic white (72.5 %), never smokers (68.5 %) with a mean (SD) age of 32.3 (4.6) years. Fifty-two (3.8 %) developed preeclampsia and 94 (6.8 %) gestational hypertension. A doubling in first trimester erythrocyte copper was associated with 78 % lower odds of preeclampsia (OR=0.22, 95 % confidence interval: 0.08, 0.60). We also observed significant associations between higher erythrocyte total arsenic and lower odds of preeclampsia (OR=0.80, 95 % CI: 0.66, 0.97) and higher vitamin B12 and increased odds of gestational hypertension (OR=1.79, 95 % CI: 1.09, 2.96), but associations were attenuated after adjustment for dietary factors. Lower levels of the overall metal mixture and essential metal mixture were associated with higher odds of preeclampsia. We found no evidence of interactions by prenatal vitamins or between metals.

CONCLUSION

Lower levels of a first-trimester essential metal mixture were associated with an increased risk of preeclampsia, primarily driven by copper. No associations were observed between other metals and HDP after adjustment for confounders and diet.

Co-exposure to Aluminium and Cadmium Mediates Postpartum Maternal Variation in Brain Architecture and Behaviour of Mice; Involvement of Oxido-nitrergic and Cholinergic Mechanisms : Postpartum effects of Aluminium and Cadmium co-exposure in pregnancy

Most research has not been done on the possible relationship between pregnant women's cross-metal exposures and postpartum neuroendocrine functions. The purpose of this study was to look into how co-exposure to aluminium chloride (AlCl3) and cadmium chloride (CdCl2) affected the neuroendocrine and neurometabolic changes in postpartum mice. A total of 24 adult pregnant female mice were used for the study. Group 1 served as control and received neither AlCl3 nor CdCl2 (n=6), group 2 comprised pregnant mice treated with AlCl3 (10mg/kg), group 3 with CdCl2 (1.5mg/kg), group 4 with a combination of AlCl3 (10 mg/kg) and CdCl2 (1.5 mg/kg).Oral treatment of animals was done daily from gestation day 7 to gestation day 20. Upon delivery and weaning on postnatal day 21 (PND 21), behavioural assessment was done on the postpartum mice and immediately followed by sacrifice for assessment of histological and neuroendocrine markers. Our findings revealed that the brain-to-body weight ratio was affected and brain oxidative stress was elevated in mice exposed to AlCl3 and CdCl2 during pregnancy. Given the strong association between postpartum hyperactivity, social interaction index, brain catalase and acetylcholinesterase activity, and the brain/body weight ratio, it is plausible that these effects have played a role in the adverse behavioural abnormalities observed in the postpartum maternal mice. Moreover, it was noted that in certain situations, co-exposures to the metals tended to have opposite effects to single metal exposures.

Investigating the progression of preeclampsia through a comprehensive analysis of genes associated with per- and polyfluoroalkyl substances

Per- and Polyfluoroalkyl Substances (PFAS) are synthetic chemicals utilized in the production of various products that possess water and dirt-repellent properties. Exposure to PFAS has been linked to numerous diseases, such as cancer and preeclampsia (PE). However, whether PFAS contributes to the advancement of PE remains uncertain. In this study, we conducted an extensive bioinformatics analysis using the Comparative Toxicogenomics Database (CTD) and Gene Expression Omnibus (GEO) databases, leading us to discover a connection between PE and four specific PFAS. Moreover, further examination revealed that six genes associated with PFAS exhibited significant diagnostic potential for individuals with PE. By employing receiver operating characteristic (ROC) curves, our PFAS-related gene-based nomogram model demonstrated outstanding predictive efficacy for diagnosing PE. Immune infiltration analysis showed that six PFAS-related genes were significantly associated with the level of immune cell infiltration. The expression of PFAS-related genes in PE patients was confirmed by collecting clinical samples. This research has offered fresh perspectives on comprehending the impact of PFAS on PE, drawing attention to the connection between environmental factors and the risks and development of PE.

Cerqueira F, Menezes-Filho JA. A Cross-Sectional Analysis Investigating Pregnant Women's Renal Function and Its Association with Lead and Cadmium Exposures-The DSAN Birth Cohort Study in Recôncavo Baiano, Brazil

Kidney dysfunction is increasing worldwide and is exacerbated by exposure to toxic metals. Also, pregnancy poses an overload on kidney function. We investigated how blood lead (PbB) and cadmium (CdB) levels were associated with kidney function in pregnant women from Recôncavo Baiano, Brazil, during their second trimester. In this cross-sectional study, the estimated glomerular filtration rate (eGFR) was calculated from serum creatinine and whole blood metal levels were measured by graphite furnace atomic absorption spectrophotometry in 136 volunteers. Sociodemographic data were collected using semi-structured questionnaires. The medians (IQR) of PbB, CdB, and eGFR were 0.85 µg/dL (0.45-1.75), 0.55 µg/L (0.08-0.91), and 121.8 mL/min/1.73 m2 (106.0-127.9), respectively. PbB medians were significantly higher in the eGFR < 90 group at 2.00 µg/dL (0.83, 3.10). After age-adjusted logistic regression, pregnant women with elevated PbB levels had decreased eGFR (OR = 1.82; 95%-CI, 1.14-3.14). However, the participants with elevated PbB levels who reported consuming alcohol during pregnancy or had CdB in the highest tertile had higher odds of reduced eGFR (OR = 2.44; 95%-CI, 1.30-5.47) and (OR = 11.22; 95% CI, 2.53-103.51), respectively. These results suggest that low Pb exposure may affect kidney function in pregnant women and calls for further investigation into toxic metal co-exposures on kidney function during pregnancy in at-risk communities.

An exploratory study on the association of multiple metals in serum with preeclampsia

Background

Individual metal levels are potential risk factors for the development of preeclampsia (PE). However, understanding of relationship between multiple metals and PE remains elusive.

Purpose

The purpose of this study was to explore whether eight metals [zinc (Zn), manganese (Mn), copper (Cu), nickel (Ni), lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg)] in serum had a certain relationship with PE.

Methods

A study was conducted in Dongguan, China. The concentrations of metals in maternal serum were assessed using inductively coupled plasma mass spectrometry (ICP-MS). Data on various factors were collected through a face-to-face interview and hospital electronic medical records. The unconditional logistic regression model, principal component analysis (PCA) and Bayesian Kernel Machine Regression (BKMR) were applied in our study.

Results

The logistic regression model revealed that the elevated levels of Cu, Pb, and Hg were associated with an increased risk of PE. According to PCA, principal component 1 (PC1) was predominated by Hg, Pb, Mn, Ni, Cu, and As, and PC1 was associated with an increased risk of PE, while PC2 was predominated by Cd and Zn. The results of BKMR indicated a significant positive cumulative effect of serum metals on PE risk, with Ni and Cu exhibiting a significant positive effect. Moreover, BKMR results also revealed the nonlinear effects of Ni and Cd.

Conclusion

The investigation suggests a potential positive cumulative impact of serum metals on the occurrence of PE, with a particular emphasis on Cu as a potential risk factor for the onset and exacerbation of PE. These findings offer valuable insights for guiding future studies on this concern.

The relationship between cadmium exposure and preeclampsia: a systematic review and meta-analysis

Background

Cadmium (Cd) is a heavy metal associated with several human disorders. Preeclampsia is a major cause of maternal mortality worldwide. The association between maternal Cd exposure and preeclampsia remains elusive.

Methods

To better understand this relationship, we conducted a systematic review and meta-analysis of eligible studies from five databases (PubMed, Embase, Web of Science, Scopus, and CNKI) from their inception to September 10, 2022. The quality of these studies was evaluated using the Newcastle-Ottawa quality assessment scale (NOS). We use random-effects models to calculate overall standardized mean differences (SMDs) and 95% confidence intervals (CIs). Sensitivity analyses were performed to assess the robustness of our results. We also evaluated publication bias using Egger's and Begg's tests. Additionally, we conducted meta-regression and sub-group analyses to identify potential sources of heterogeneity between studies.

Results

Our analysis included a total of 17 studies with 10,373 participants. We found a significant association between maternal cadmium exposure and the risk of preeclampsia (SMD 0.27, 95% CI 0.09-0.44, p < 0.01). No significant publication bias was detected in Begg's or Egger's tests. Meta-regression suggested that geographical location, year of publication, cadmium samples, sample size, and measurement methods did not contribute to heterogeneity between studies.

Conclusion

Our findings suggest that maternal blood cadmium levels are associated with an increased risk of preeclampsia. In contrast, the pregnant women's urine or placental levels of cadmium may not suggest preeclamptic risk during pregnancy. Further high-quality clinical studies and animal experiments are needed to understand this association better.

Systematic review registration

PROSPERO, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=361291, identifier: CRD42022361291.

Association of chromosomal abnormalities with prenatal exposure to heavy metals: A nested case-control study in high-risk pregnant women in China

Prenatal exposure to heavy metals causes multiple hazards to fetal growth and development. Epidemiological studies on the association between heavy metals and fetal chromosomal abnormalities (CAs) are lacking. We conducted a nested case-control study in a cohort of high-risk pregnant women in China from September 2018 to June 2021. A total of 387 participants were diagnosed with fetal CAs in the case group and 699 were diagnosed with a normal karyotype in the control group. Amniotic fluid concentrations of 10 metals (barium, cobalt, antimony, manganese, ferrum, copper, selenium, strontium, vanadium, and chromium) were measured using inductively coupled plasma-mass spectrometry. We applied quantile g-computation and weighted quantile sum regression to assess the overall effect of metal mixtures and identify metals with significant weight. Logistic and Poisson regression analyses were used to estimate the effects of metals on CAs and CAs subtypes. Our results showed that the metal mixture concentrations were positively associated with the risk of fetal CAs. In adjusted logistic models, Sb was associated with fetal CAs (OR=1.15, 95% CI: 1.02-1.30), and revealed a linear dose-response relationship between Sb level and the risk of fetal CAs. Additionally, the exploratory analysis revealed that Sb levels were associated with Klinefelter syndrome (OR=1.452, 95% CI: 1.063-1.984) and Turner syndrome (OR=1.698; 95% CI,1.048-2.751). Our study revealed that metal mixtures are associated with a higher risk of fetal CAs and that this association may be driven primarily by Sb. Moreover, we provide a genetic perspective on the effects of heavy metals on sexual development in humans.

Zinc and selenium attenuate quaternary heavy metal mixture-induced testicular damage via amplification of the antioxidant system, reduction in metal accumulation, inflammatory and apoptotic biomarkers

Heavy metals (HMs) such as cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) are highly toxic elements. They are often found together in nature as a heavy metal mixture (HMM) and are known to contribute to subfertility/infertility as environmental pollutants. This study aims to evaluate the potential benefits of treating HMM-induced testicular pathophysiology with zinc (Zn) and/or selenium (Se). Six-week-old male Sprague Dawley rats were grouped into 5 (n = 7). The control group received deionized water, while the other groups were treated with PbCl2 (20 mg kg-1), CdCl2 (1.61 mg kg-1), HgCl2 (0.40 mg kg-1), and Na2AsO3 (10 mg kg-1) in deionized water for 60 days. Additionally, groups III to V received Zn, Se, and Zn/Se, respectively, for 60 days. The study evaluated testis weight, metal accumulation, sperm analysis, FSH, LH, testosterone, prolactin, oxidative stress, antioxidants, pro-inflammatory and apoptotic markers, and presented structural changes in the testis as micrographs. HMM caused a significant increase in testis weight, metal accumulation, prolactin, oxidative stress, and pro-inflammatory and apoptotic markers, while significantly decreasing semen analysis, FSH, LH, and testosterone. Histology showed decreased spermatogenesis and spermiogenesis, as evidenced by the structure of the germ cells and spermatids. However, Zn, Se, or both ameliorated and reversed some of the observed damages. This study provides further evidence for the mitigative potential of Zn, Se, or both in reversing the damage inflicted by HMM in the testis, and as a countermeasure towards improving HM-induced decrease in public health fecundity.

Graphical abstract

Effects of Xenobiotic Compounds on Preeclampsia and Potential Mechanisms

Preeclampsia (PE) refers to a disease with new hypertension and albuminuria or other end-organ damage after 20 weeks of pregnancy. As a major complication of pregnancy, PE can increase the morbidity and mortality of pregnant women and fetuses and cause serious social burden. Recently, it has been found that exposure to xenobiotic compounds, especially endocrine disruptors in the environment, may contribute to the development of PE. However, the underlying mechanism is still unclear. It is generally believed that PE is related to placental dysplasia, spiral artery remodelling failure, oxidative stress, etc. Therefore, in order to better prevent the occurrence of PE and reduce the damage and impact on mother and fetus, this paper reviews the role and potential mechanism of PE induced by exogenous chemicals and provides an outlook on the environmental etiology of PE.

Individual, Independent, and Joint Associations of Toxic Metals and Manganese on Hypertensive Disorders of Pregnancy: Results from the MIREC Canadian Pregnancy Cohort

BACKGROUND

Toxic metals, such as lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg), may be associated with a higher risk of gestational hypertension and preeclampsia, whereas manganese (Mn) is an essential metal that may be protective.

OBJECTIVES

We estimated the individual, independent, and joint associations of Pb, Cd, As, Hg, and Mn on the risk of developing gestational hypertension and preeclampsia in a cohort of Canadian women.

METHODS

Metal concentrations were analyzed in first and third trimester maternal blood (n = 1,560 ). We measured blood pressure after 20 wk gestation to diagnose gestational hypertension, whereas proteinuria and other complications defined preeclampsia. We estimated individual and independent (adjusted for coexposure) relative risks (RRs) for each doubling of metal concentrations and examined interactions between toxic metals and Mn. We used quantile g-computation to estimate the joint effect of trimester-specific exposures.

RESULTS

Each doubling of third trimester Pb (RR = 1.54 ; 95% CI: 1.06, 2.22) and first trimester blood As (RR = 1.25 ; 95% CI: 1.01, 1.58) was independently associated with a higher risk of developing preeclampsia. First trimester blood As (RR = 3.40 ; 95% CI: 1.40, 8.28) and Mn (RR = 0.63 ; 95% CI: 0.42, 0.94) concentrations were associated with a higher and lower risk, respectively, of developing gestational hypertension. Mn modified the association with As such that the deleterious association with As was stronger at lower concentrations of Mn. First trimester urinary dimethylarsinic acid concentrations were not associated with gestational hypertension (RR = 1.31 ; 95% CI: 0.60, 2.85) or preeclampsia (RR = 0.92 ; 95% CI: 0.68, 1.24). We did not observe overall joint effects for blood metals.

DISCUSSION

Our results confirm that even low blood Pb concentrations are a risk factor for preeclampsia. Women with higher blood As concentrations combined with lower Mn in early pregnancy were more likely to develop gestational hypertension. These pregnancy complications impact maternal and neonatal health. Understanding the contribution of toxic metals and Mn is of public health importance. https://doi.org/10.1289/EHP10825.

Exposure to essential and non-essential trace elements and risks of congenital heart defects: A narrative review

Congenital heart defects (CHDs) are congenital abnormalities involving the gross structures of the heart and large blood vessels. Environmental factors, genetic factors and their interactions may contribute to the pathogenesis of CHDs. Generally, trace elements can be classified into essential trace elements and non-essential trace elements. Essential trace elements such as copper (Cu), zinc (Zn), iron (Fe), selenium (Se), and manganese (Mn) play important roles in human biological functions such as metabolic function, oxidative stress regulation, and embryonic development. Non-essential trace elements such as cadmium (Cd), arsenic (As), lead (Pb), nickle (Ni), barium (Ba), chromium (Cr) and mercury (Hg) are harmful to health even at low concentrations. Recent studies have revealed the potential involvement of these trace elements in the pathogenesis of CHDs. In this review, we summarized current studies exploring exposure to essential and non-essential trace elements and risks of CHDs, in order to provide further insights for the pathogenesis and prevention of CHDs.

Genetic susceptibility and lifestyle modify the association of long-term air pollution exposure on major depressive disorder: a prospective study in UK Biobank

BACKGROUND

Evidence linking air pollution to major depressive disorder (MDD) remains sparse and results are heterogeneous. In addition, the evidence about the interaction and joint associations of genetic risk and lifestyle with air pollution on incident MDD risk remains unclear. We aimed to examine the association of various air pollutants with the risk of incident MDD and assessed whether genetic susceptibility and lifestyle influence the associations.

METHODS

This population-based prospective cohort study analyzed data collected between March 2006 and October 2010 from 354,897 participants aged 37 to 73 years from the UK Biobank. Annual average concentrations of PM_2.5, PM₁₀, NO₂, and NO_x were estimated using a Land Use Regression model. A lifestyle score was determined based on a combination of smoking, alcohol drinking, physical activity, television viewing time, sleep duration, and diet. A polygenic risk score (PRS) was defined using 17 MDD-associated genetic loci.

RESULTS

During a median follow-up of 9.7 years (3,427,084 person-years), 14,710 incident MDD events were ascertained. PM_2.5 (HR: 1.16, 95% CI: 1.07-1.26; per 5 μg/m³) and NO_x (HR: 1.02, 95% CI: 1.01-1.05; per 20 μg/m³) were associated with increased risk of MDD. There was a significant interaction between the genetic susceptibility and air pollution for MDD (P-interaction < 0.05). Compared with participants with low genetic risk and low air pollution, those with high genetic risk and high PM_2.5 exposure had the highest risk of incident MDD (PM_2.5: HR: 1.34, 95% CI: 1.23-1.46). We also observed an interaction between PM_2.5 exposure and unhealthy lifestyle (P-interaction < 0.05). Participants with the least healthy lifestyle and high air pollution exposures had the highest MDD risk when compared to those with the most healthy lifestyle and low air pollution (PM_2.5: HR: 2.22, 95% CI: 1.92-2.58; PM₁₀: HR: 2.09, 95% CI: 1.78-2.45; NO₂: HR: 2.11, 95% CI: 1.82-2.46; NO_x: HR: 2.28, 95% CI: 1.97-2.64).

CONCLUSIONS

Long-term exposure to air pollution is associated with MDD risk. Identifying individuals with high genetic risk and developing healthy lifestyle for reducing the harm of air pollution to public mental health.

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.

Non-essential and essential trace element mixtures and kidney function in early pregnancy - A cross-sectional analysis in project viva

Some trace elements are established nephrotoxicants, yet their associations with kidney function remain understudied in the context of pregnancy, a time of substantial change in kidney physiology and function. We aimed to estimate the individual and joint associations of trace element mixtures with maternal kidney function during the 1st trimester of pregnancy (mean 9.7 gestational weeks). 1040 women from Project Viva contributed blood samples which were assessed for erythrocyte non-essential [arsenic (As), cadmium (Cd), cesium (Cs), mercury (Hg), lead (Pb)] and essential [barium (Ba), magnesium (Mg), manganese (Mn), selenium (Se), and Zinc (Zn)] trace elements, and plasma creatinine for kidney function. We estimated glomerular filtration rate using the Chronic Kidney Disease Epidemiology Collaboration (eGFRCKD-EPI) equation without race-adjustment factors. We examined associations of eGFRCKD-EPI with individual trace elements using multivariable linear regression and their mixtures using quantile-based g-computation, adjusting for sociodemographics, pregnancy characteristics, and diet. Participants in our study were predominantly White (75%), college graduates (72%), and had household income >$70,000/year (63%). After adjusting for covariates, higher Pb (β -3.51 ml/min/1.73 m2; 95% CI -5.83, -1.18) concentrations were associated with lower eGFRCKD-EPI, while higher Mg (β 10.53 ml/min/1.73 m2; 95% CI 5.35, 15.71), Se (β 5.56 ml/min/1.73 m2; 95% CI 0.82, 10.31), and Zn (β 5.88 ml/min/1.73 m2; 95% CI 0.51, 11.26) concentrations were associated with higher eGFRCKD-EPI. In mixture analyses, higher non-essential trace elements mixture concentration was associated with reduced eGFRCKD-EPI (Ψ -1.03 ml/min/1.73 m2; 95% CI: 1.92, -0.14). Conversely, higher essential trace elements mixture concentration was associated with higher eGFR (Ψ 1.42; 95% CI: 0.48, 2.37). Exposure to trace elements in early pregnancy may influence women's kidney function although reverse causation cannot be eliminated in this cross-sectional analysis. These findings have important implications for long-term cardiovascular and postpartum kidney health that warrant additional studies.

Maternal Mercury Exposure and Hypertensive Disorders of Pregnancy: A Systematic Review

OBJECTIVE

 The present review aimed to synthesize the evidence regarding mercury (Hg) exposure and hypertensive disorders of pregnancy (HDP).

DATA SOURCES

 The PubMed, BVS/LILACS, SciELO and UFRJ's Pantheon Digital Library databases were systematically searched through June 2021.

STUDY SELECTION

 Observational analytical articles, written in English, Spanish, or Portuguese, without time restriction.

DATA COLLECTION

 We followed the PICOS strategy, and the methodological quality was assessed using the Downs and Black checklist.

DATA SYNTHESIS

 We retrieved 77 articles, of which 6 met the review criteria. They comprised 4,848 participants, of which 809 (16.7%) had HDP and 4,724 (97.4%) were environmentally exposed to Hg (fish consumption and dental amalgam). Mercury biomarkers evaluated were blood (four studies) and urine (two studies). Two studies found a positive association between Hg and HDP in the group with more exposure, and the other four did not present it. The quality assessment revealed three satisfactory and three good-rated studies (mean: 19.3 ± 1.6 out 28 points). The absence or no proper adjustment for negative confounding factor, such as fish consumption, was observed in five studies.

CONCLUSION

 We retrieved only six studies, although Hg is a widespread toxic metal and pregnancy is a period of heightened susceptibility to environmental threats and cardiovascular risk. Overall, our review showed mixed results, with two studies reporting a positive association in the group with more exposure. However, due to the importance of the subject, additional studies are needed to elucidate the effects of Hg on HDP, with particular attention to adjusting negative confounding.

A global perspective of correlation between maternal blood lead levels and risks of preeclampsia: An updated systematic review and meta-analysis

Background

Preeclampsia (PE) is a specific hypertensive disorder in pregnancy. Lead (Pb) is a heavy metal that affects women's reproductive health. However, it is unclear whether lead exposure during can predispose maternal risk of developing preeclampsia. This systematic review and meta-analysis study aimed to explore the association.

Methods

We searched studies from three databases (PubMed, Web of Science, Embase). Only case-control, cross-sectional, and cohort studies reporting maternal blood lead levels (BLL) and PE were included from database inception to 31st July 2022. Pregnant women with blood lead levels measured were eligible. Those healthy pregnant women who did not develop preeclampsia were assessed as comparators. Letters, comments, case reports, and reviews were excluded. Newcastle-Ottawa Scale (NOS) and its adaptive form were applied for assessment. The random-effects method (REM) was applied to calculate the standardized mean difference (SMD) with a 95% confidence interval (CI). Stata 16.0 and RevMan 5.3 were the software used for data extraction and analysis.

Results

25 studies out of 1,808 articles made the finalist for systematic reviews, of which 21 underwent further quantity analysis. A total of 1,533 preeclamptic women and 10,998 healthy pregnant controls were included in the meta-analysis. The overall result revealed that maternal lead exposure was significantly higher in women with preeclampsia (SMD: 1.06, 95% CI 0.69, 1.43); (I ² = 96.40%; P = 0.000).

Conclusion

This study demonstrates that maternal lead exposure is associated with preeclampsia during pregnancy. The association is present even in low blood lead levels. The conclusion should be taken seriously and women should avoid unexpected exposure to a lead-containing environment as much as possible.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=347220, identifier: CRD42022347220.

Maternal cadmium exposure impairs placental angiogenesis in preeclampsia through disturbing thyroid hormone receptor signaling

Cadmium is a ubiquitous environmental pollutant, which can increase the risk of preeclampsia. This study was designed to determine the mechanism of cadmium exposure during pregnancy impaired placental angiogenesis that was associated with the occurrence of preeclampsia. The effects of cadmium exposure on placental thyroid hormone receptor signaling were explored. JEG3 cells were treated with CdCl₂ (20 μM) and the Dio2 inhibitor, IOP (100 μM). Cadmium levels in maternal blood and placentae were increased in preeclampsia group. Placental angiogenesis of preeclampsia was decreased with decreased expression of PLGF and VEGF and increased expression of sFlt1. Meanwhile, the expression and nuclear translocation of thyroid hormone receptor α were decreased in preeclampsia placenta, as well as the expression of Dio2, but not the expression and nuclear translocation of thyroid hormone receptor β. Furthermore, we found that cadmium exposure downregulated the expression of thyroid hormone receptor α and Dio2, but not the expression of thyroid hormone receptor β in JEG3 cells. Also, we found that cadmium exposure decreased the expression of PLGF and VEGF and increased the expression of sFlt1 in JEG3 cells. IOP pretreatment decreased the expression of PLGF and increased the expression of sFlt1. In conclusion, our results elucidated that cadmium exposure would impair placental angiogenesis in preeclampsia through disturbing thyroid hormone receptor signaling.

The Relationship Between Preeclampsia and Arsenic Concentration in the Peripheral Blood

Preeclampsia (PE) is a pregnancy-specific disorder, which is one of the leading causes of maternal, fetal, and neonatal death, particularly in developing countries. Arsenic (As), which is commonly found in soil and groundwater, has been associated with various complications of pregnancy, such as spontaneous abortion, hypertension, and stillbirth. Hence, the study was used to explore the relationship between PE and blood concentration of As in this study. Blood concentration of As during pregnancy was measured by inductively coupled plasma mass spectrometry (ICP-MS). The results shown that the mean blood concentration of As was gradually increased from the control group to the severe PE group (P < 0.0001). Elevated blood concentration of As was associated with the prevalence of PE (OR = 12.81, 95% CI: 2.43-67.39 and 27.55, 1.75-433.43 for middle and high vs. low). Furthermore, elevated blood concentration of As was associated with the severity of PE. Additionally, we observed that blood concentration of As was associated with the hypoproteinemia (P = 0.001, rs = 0.37). Blood concentration of As was negatively corelated with the mean corpuscular volume (MCV) (P = 0.040, rs =  - 0.23) and positively corelated with the mean corpuscular hemoglobin concentration (MCHC) (P = 0.044, rs = 0.23). Overall, our results indicated that the blood concentration of As can significantly predict the occurrence of PE. Additionally, we provided evidence that blood concentration of As may affect the occurrence of hypoproteinemia. These findings may provide some ideas for the prevention of PE and pregnancy complications.

Exposure to metal mixtures and hypertensive disorders of pregnancy: A nested case-control study in China

Exposure to metals has been linked with the risk of hypertensive disorders of pregnancy (HDP), but little is known about the potential effects of exposure to metal mixtures. Thus, our study aimed to investigated the impact of a complex mixture of metals on HDP, especially the interactions among metal mixtures. We did a population-based nested case-control study from October 2013 to October 2016 in Wuhan, China, including 146 HDP cases and 292 controls. Plasma concentrations of Aluminum (Al), Barium (Ba), Cobalt (Co), Copper (Cu), Lead (Pb), Mercury (Hg), Molybdenum (Mo), Nickel (Ni), Selenium (Se), Strontium (Sr), Thallium (Tl), and Vanadium (V) were measured and collected between 10 and 16 gestational weeks. We employed quantile g-computation, conditional logistic regression models, and Bayesian Kernel Machine Regression (BKMR) to assess the association of individual metals and metal mixtures with HDP risk. In the quantile g-computation, the OR for a joint tertile increase in plasma concentrations was 3.67 (95% CI: 1.70, 7.91). Hg contributed the largest positive weights and followed by Al, Ni, and V. In conditional logistic regression models, concentrations of Hg, Al, Ni, and V were significantly associated with the risk of HDP (p-FDR < 0.05). Compared to the lowest tertiles, the ORs (95% CI) for the highest tertiles of these four metals were 2.67 (1.44, 4.95), 3.09 (1.70, 5.64), 5.31 (2.68, 10.53), and 4.52 (2.26, 9.01), respectively. In the BKMR analysis, we observed a linear positive association between Hg, Al, V, and HDP, and a nonlinear relationship between Ni and HDP. A potential interaction between Al and V was also identified. We found that exposure to metal mixtures in early pregnancy, both individually and as a mixture, was associated with the risk of HDP. Potential interaction effects of Al and V on the risk of HDP may exist.

Clinical Significance of Peptidase M20 Domain Containing 1 Ii Patients with Carotid Atherosclerosis

Fundamento

A aterosclerose é a principal causa da maioria das doenças cardiovasculares, e novos biomarcadores para essa condição são sempre necessários. O domínio da peptidase M20 contendo 1 (PM20D1) está associado ao metabolismo lipídico e à obesidade. No entanto, nenhum estudo se concentra no papel do PM20D1 na aterosclerose carotídea.

Objetivo

O objetivo deste estudo foi investigar o papel do PM20D1 em pacientes com aterosclerose carotídea.

Métodos

Estudo observacional prospectivo conduzido com um total de 231 pacientes com aterosclerose carotídea que estiveram em nosso departamento entre julho de 2018 e dezembro de 2019. Amostras de sangue e dados médicas foram obtidos de outros 231 indivíduos saudáveis com o mesmo índice de massa corporal (IMC) dos pacientes com aterosclerose carotídea. O PM20D1 sérico foi determinado por ensaio imunossorvente ligado a enzima (ELISA). As características clínicas e demográficas de todos os pacientes foram listadas, incluindo idade, sexo biológico, IMC e histórico médico. Os níveis de proteína C reativa (PCR), fator de necrose tumoral, homocisteína, colesterol total, triglicerídeos, leptina-colesterol de alta densidade e leptina-colesterol de baixa densidade foram registrados. Realizou-se análise estatística no software SPSS, com p<0,05 considerado estatisticamente significante.

Resultados

Os níveis séricos de PM20D1 foram marcadamente mais baixos em pacientes com aterosclerose carotídea comparados aos controles saudáveis, sendo significativamente mais baixos em pacientes com aterosclerose carotídea grave e pacientes com aterosclerose carotídea/acidente vascular cerebral. Pacientes com placas instáveis apresentaram PM20D1 marcadamente menor quando comparados a pacientes com placas estáveis. Nenhuma diferença significativa foi encontrada entre pacientes com aterosclerose carotídea com diferentes IMC. Pacientes com níveis mais elevados de PM20D1 apresentaram expressão significativamente menor de PCR, fator de necrose tumoral, homocisteína, triglicerídeos, colesterol total e colesterol de baixa densidade. PM20D1 correlacionou-se negativamente com PCR, fator de necrose tumoral, homocisteína, colesterol total e leptina de baixa densidade em pacientes com aterosclerose carotídea, podendo ser usado como biomarcador para pacientes com aterosclerose carotídea grave ou com aterosclerose carotídea e acidente vascular cerebral. Sexo biológico, fator de necrose tumoral, homocisteína e PM20D1 foram considerados fatores de risco para aterosclerose carotídea.

Conclusão

O PM20D1 estava diminuído em pacientes com aterosclerose carotídea e foi associado com gravidade, estabilidade da placa, níveis de PCR, fator de necrose tumoral, homocisteína, triglicerídeos, colesterol total e colesterol de baixa densidade em pacientes com aterosclerose carotídea.

The Role of Inorganics in Preeclampsia Assessed by Multiscale Multimodal Characterization of Placentae

Preeclampsia is one of the most dangerous diseases in pregnancy. Because of the hypertensive nature of preeclampsia, placental calcifications are believed to be a predictor for its occurrence, analogous to their role in cardiovascular diseases. However, the prevalence and the relevance of calcifications for the clinical outcome with respect to preeclampsia remains controversial. In addition, the role of other inorganic components present in the placental tissue in the development of preeclampsia has rarely been investigated. In this work, we therefore characterized inorganic constituents in placental tissue in groups of both normotensive and preeclamptic patients (N = 20 each) using a multi-scale and multi-modal approach. Examinations included elemental analysis (metallomics), sonography, computed tomography (CT), histology, scanning electron microscopy, X-ray fluorescence and energy dispersive X-ray spectroscopy. Our data show that tissue contents of several heavy metals (Al, Cd, Ni, Co, Mn, Pb, and As) were elevated whereas the Rb content was decreased in preeclamptic compared to normotensive placentae. However, the median mineral content (Ca, P, Mg, Na, K) was remarkably comparable between the two groups and CT showed lower calcified volumes and fewer crystalline deposits in preeclamptic placentae. Electron microscopy investigations revealed four distinct types of calcifications, all predominantly composed of calcium, phosphorus and oxygen with variable contents of magnesium in tissues of both maternal and fetal origin in both preeclamptic and normotensive placentae. In conclusion our study suggests that heavy metals, combined with other factors, can be associated with the development of preeclampsia, however, with no obvious correlation between calcifications and preeclampsia.

Interactions of antimony with biomolecules and its effects on human health

Antimony (Sb) pollution has increased health risks to humans as a result of extensive application in diverse fields. Exposure to different levels of Sb and its compounds will directly or indirectly affect the normal function of the human body, whereas limited human health data and simulation studies delay the understanding of this element. In this review, we summarize current research on the effects of Sb on human health from different perspectives. First, the exposure pathways, concentration and excretion of Sb in humans are briefly introduced, and several studies have revealed that human exposure to high levels of Sb will cause higher concentrations in body tissues. Second, interactions between Sb and biomolecules or other nonbiomolecules affected biochemical processes such as gene expression and hormone secretion, which are vital for causing and understanding health effects and mechanisms. Finally, we discuss the different health effects of Sb at the biological level from small molecules to individual. In conclusion, exposure to high levels of Sb compounds will increase the risk of disease by affecting different cell signaling pathways. In addition, the appropriate form and dose of Sb contribute to inhibit the development of specific diseases. Key challenges and gaps in toxicity or benefit effects and mechanisms that still hinder risk assessment of human health are also identified in this review. Systematic studies on the relationships between the biochemical process of Sb and human health are needed.

Exposure to Metal Mixtures in Association with Cardiovascular Risk Factors and Outcomes: A Scoping Review

Since the National Institute of Environmental Health Sciences (NIEHS) declared conducting combined exposure research as a priority area, literature on chemical mixtures has grown dramatically. However, a systematic evaluation of the current literature investigating the impacts of metal mixtures on cardiovascular disease (CVD) risk factors and outcomes has thus far not been performed. This scoping review aims to summarize published epidemiology literature on the cardiotoxicity of exposure to multiple metals. We performed systematic searches of MEDLINE (PubMed), Scopus, and Web of Science to identify peer-reviewed studies employing statistical mixture analysis methods to evaluate the impact of metal mixtures on CVD risk factors and outcomes among nonoccupationally exposed populations. The search was limited to papers published on or after 1998, when the first dedicated funding for mixtures research was granted by NIEHS, through 1 October 2021. Twenty-nine original research studies were identified for review. A notable increase in relevant mixtures publications was observed starting in 2019. The majority of eligible studies were conducted in the United States (n = 10) and China (n = 9). Sample sizes ranged from 127 to 10,818. Many of the included studies were cross-sectional in design. Four primary focus areas included: (i) blood pressure and/or diagnosis of hypertension (n = 15), (ii) risk of preeclampsia (n = 3), (iii) dyslipidemia and/or serum lipid markers (n = 5), and (iv) CVD outcomes, including stroke incidence or coronary heart disease (n = 8). The most frequently investigated metals included cadmium, lead, arsenic, and cobalt, which were typically measured in blood (n = 15). The most commonly utilized multipollutant analysis approaches were Bayesian kernel machine regression (BKMR), weighted quantile sum regression (WQSR), and principal component analysis (PCA). To our knowledge, this is the first scoping review to assess exposure to metal mixtures in relation to CVD risk factors and outcomes. Recommendations for future studies evaluating the associations of exposure to metal mixtures with risk of CVDs and related risk factors include extending environmental mixtures epidemiologic studies to populations with wider metals exposure ranges, including other CVD risk factors or outcomes outside hypertension or dyslipidemia, using repeated measurement of metals to detect windows of susceptibility, and further examining the impacts of potential effect modifiers and confounding factors, such as fish and seafood intake.

Urinary metals and maternal circulating extracellular vesicle microRNA in the MADRES pregnancy cohort

Exposure to metals increases risk for pregnancy complications. Extracellular vesicle (EV) miRNA contribute to maternal-foetal communication and are dysregulated in pregnancy complications. However, metal impacts on maternal circulating EV miRNA during pregnancy are unknown. Our objective was to investigate the impact of multiple metal exposures on EV miRNA in maternal circulation during pregnancy in the MADRES Study. Associations between urinary concentrations of nine metals and 106 EV miRNA in maternal plasma during pregnancy were investigated using robust linear regression (N = 231). Primary analyses focused on metal-miRNA associations in early pregnancy (median: 12.3 weeks gestation). In secondary analyses, we investigated associations with late pregnancy miRNA counts (median: 31.8 weeks gestation) in a subset of participants (N = 184) with paired measures. MiRNA associated with three or more metals (P_FDR<0.05) were further investigated using Bayesian Kernel Machine Regression (BKMR), an environmental mixture method. Thirty-five miRNA were associated (P_FDR<0.05) with at least one metal in early pregnancy. One association (an inverse association between cobalt and miR-150-5p) remained statistically significant when evaluating late pregnancy miRNA counts. Eight miRNA (miR-302b-3p, miR-199a-5p, miR-188-5p, miR-138-5p, miR-212-3p, miR-608, miR-1272, miR-19b-3p) were associated with three metals (barium, mercury, and thallium) in early pregnancy, and their predicted target genes were enriched in pathways important for placental development. Results were consistent when using BKMR. Early pregnancy exposure to barium, mercury, and thallium may have short-term impacts on a common set of EV miRNA which target pathways important for placental development.

Nephrotoxic Metal Mixtures and Preadolescent Kidney Function

Exposure to metals including lead (Pb), cadmium (Cd), and arsenic (As), may impair kidney function as individual toxicants or in mixtures. However, no single medium is ideal to study multiple metals simultaneously. We hypothesized that multi-media biomarkers (MMBs), integrated indices combining information across biomarkers, are informative of adverse kidney function. Levels of Pb, Cd, and As were quantified in blood and urine in 4–6-year-old Mexican children (n = 300) in the PROGRESS longitudinal cohort study. We estimated the mixture effects of these metals, using weighted quantile sum regression (WQS) applied to urine biomarkers (Umix), blood biomarkers (Bmix), and MMBs, on the cystatin C-based estimated glomerular filtration rate (eGFR) and serum cystatin C assessed at 8–10 years of age, adjusted for covariates. Quartile increases in Umix and the MMB mixture were associated with 2.5% (95%CI: 0.1, 5.0) and 3.0% (95%CI: 0.2, 5.7) increased eGFR and −2.6% (95% CI: −5.1%, −0.1%) and −3.3% (95% CI: −6.5%, −0.1%) decreased cystatin C, respectively. Weights indicate that the strongest contributors to the associations with eGFR and serum cystatin C were Cd and Pb, respectively. MMBs detected mixture effects distinct from associations with individual metals or media-type, highlighting the benefits of incorporating information from multiple exposure media in mixtures analyses.

Exposure to heavy metals and trace minerals in first trimester and maternal blood pressure change over gestation

BACKGROUND

While several heavy metals and trace minerals have been linked with hypertensive disorders during pregnancy (HDP) in women, no studies have estimated the relationship of exposure to these chemicals, both independently and as a mixture, with systolic blood pressure (SBP) or diastolic blood pressure (DBP) over gestation.

OBJECTIVES

We examined individual and joint effects of 1^st trimester chemicals with SBP and DBP over gestation, and whether those chemicals were associated with HDP.

METHODS

We used data from 1832 non-obese pregnant women with low-risk antenatal profiles from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies - Singleton cohort (2009-2013). In plasma collected from women at 8-13 weeks' gestation (baseline enrollment), we measured heavy metals, barium (Ba), cesium (Cs), antimony (Sb), as well as trace minerals, cobalt (Co), copper (Cu), molybdenum (Mo), selenium (Se), and zinc (Zn). We obtained BP at baseline and throughout gestation until delivery and diagnosis of HDP from medical records. We used Bayesian Kernel Machine Regression (BKMR) as well as traditional linear and logistic regressions to examine the cross-sectional associations of chemicals with baseline BP and HDP. We used linear mixed effect regression to examine longitudinal associations between chemicals and rate of weekly change in BP in each trimester. We adjusted for sociodemographic and lifestyle factors and pre-pregnancy body mass index in all models.

RESULTS

BKMR revealed that comparing the entire chemical mixture at the 90^th percentile vs. the 50^th percentile was associated with a 1.61 mmHg (95% CI: 0.41, 2.81) higher SBP and a 1.09 mmHg (0.10, 2.09) higher DBP. No interactions were observed between chemicals. Accounting for chemical co-exposure in BKMR, each interquartile range (IQR) increment in Cu was associated with a 0.67 mmHg (0.02, 1.32) higher SBP and a 0.60 mmHg (0.08, 1.12) higher DBP at baseline; each IQR increment in Se was associated with a 0.67 mmHg (0.05, 1.29) higher SBP but not DBP. In longitudinal analyses, women with higher (i.e., above median concentration) baseline Cu had a 0.09 mmHg (0.01, 0.17) and 0.06 mmHg (0.001, 0.12) larger weekly decrease in SBP and DBP in 2^nd trimester, respectively. Women with higher baseline Ba had a 0.12 mmHg (0.04, 0.20) larger weekly increase in SBP in 2^nd trimester, while women with higher Cs had a 0.05 mmHg (0.01, 0.10) larger weekly increase in DBP in 3^rd trimester. None of the chemicals examined were significantly associated with HDP.

CONCLUSIONS

In this multi-ethnic cohort of women with low antenatal risk, plasma metals and trace minerals in early pregnancy, both individually and as a mixture, were statistically significantly associated with BP during gestation in small magnitude and in different directions, but not with HDP. The implications of these findings for women's postpartum BP and future cardiovascular health remains to be investigated.