Arsenic Exposure and Predicted 10-Year Atherosclerotic Cardiovascular Risk Using the Pooled Cohort Equations in U.S. Hypertensive Adults

Risk assessment of complex organoarsenic species in food

The European Commission asked EFSA for a risk assessment on complex organoarsenic species in food. They are typically found in marine foods and comprise mainly arsenobetaine (AsB), arsenosugars and arsenolipids. For AsB, no reference point (RP) could be derived because of insufficient toxicity data. AsB did not show adverse effects in the two available repeat dose toxicity tests in rodents. It has not shown genotoxicity in in vitro assays. There is no indication of an association with adverse outcomes in human studies. The highest 95th percentile exposure for AsB was observed in 'Toddlers' with an estimate of 12.5 μg As/kg bw per day (AsB expressed as elemental arsenic). There is sufficient evidence to conclude that AsB at current dietary exposure levels does not raise a health concern. For glycerol arsenosugar (AsSugOH) a RP of 0.85 mg As/kg bw per day was derived based on the BMDL10 values for cognitive and motor function in mice. A margin of exposure (MOE) of ≥ 1000 would not raise a health concern. The highest 95th percentile estimate of exposure for AsSugOH (for adult consumers of red seaweed Nori/Laver) was 0.71 μg As/kg bw per day (AsSugOH expressed as elemental arsenic), which results in an MOE > 1000, not raising a health concern. Based on qualitative consideration of all identified uncertainties, it is regarded likely that the dietary exposures to AsB and AsSugOH do not raise a health concern. No conclusions could be drawn regarding other arsenosugars. No risk characterisation could be conducted for arsenolipids, due to the lack of data.

Metals on the Menu-Analyzing the Presence, Importance, and Consequences

Metals are integral components of the natural environment, and their presence in the food supply is inevitable and complex. While essential metals such as sodium, potassium, magnesium, calcium, iron, zinc, and copper are crucial for various physiological functions and must be consumed through the diet, others, like lead, mercury, and cadmium, are toxic even at low concentrations and pose serious health risks. This study comprehensively analyzes the presence, importance, and consequences of metals in the food chain. We explore the pathways through which metals enter the food supply, their distribution across different food types, and the associated health implications. By examining current regulatory standards for maximum allowable levels of various metals, we highlight the importance of ensuring food safety and protecting public health. Furthermore, this research underscores the need for continuous monitoring and management of metal content in food, especially as global agricultural and food production practices evolve. Our findings aim to inform dietary recommendations, food fortification strategies, and regulatory policies, ultimately contributing to safer and more nutritionally balanced diets.

Environmental Impacts on Cardiovascular Health and Biology: An Overview

Environmental stressors associated with human activities (eg, air and noise pollution, light disturbance at night) and climate change (eg, heat, wildfires, extreme weather events) are increasingly recognized as contributing to cardiovascular morbidity and mortality. These harmful exposures have been shown to elicit changes in stress responses, circadian rhythms, immune cell activation, and oxidative stress, as well as traditional cardiovascular risk factors (eg, hypertension, diabetes, obesity) that promote cardiovascular diseases. In this overview, we summarize evidence from human and animal studies of the impacts of environmental exposures and climate change on cardiovascular health. In addition, we discuss strategies to reduce the impact of environmental risk factors on current and future cardiovascular disease burden, including urban planning, personal monitoring, and mitigation measures.

Didactical approaches and insights into environmental processes and cardiovascular hazards of arsenic contaminants

Arsenic, as a metalloid, has the ability to move and transform in different environmental media. Its widespread contamination has become a significant environmental problem and public concern. Arsenic can jeopardize multiple organs through various pathways, influenced by environmental bioprocesses. This article provides a comprehensive overview of current research on the cardiovascular hazards of arsenic. A bibliometric analysis revealed that there are 376 papers published in 145 journals, involving 40 countries, 631 institutions, and 2093 authors, all focused on arsenic-related concerns regarding cardiovascular health. China and the U.S. have emerged as the central hubs of collaborative relationships and have the highest number of publications. Hypertension and atherosclerosis are the most extensively studied topics, with redox imbalance, apoptosis, and methylation being the primary mechanistic clues. Cardiovascular damage caused by arsenic includes arrhythmia, cardiac remodeling, vascular leakage, and abnormal angiogenesis. However, the current understanding is still inadequate over cardiovascular impairments, underlying mechanisms, and precautionary methods of arsenic, thus calling an urgent need for further studies to bridge the gap between environmental processes and arsenic hazards.

Update of the risk assessment of inorganic arsenic in food

The European Commission asked EFSA to update its 2009 risk assessment on arsenic in food carrying out a hazard assessment of inorganic arsenic (iAs) and using the revised exposure assessment issued by EFSA in 2021. Epidemiological studies show that the chronic intake of iAs via diet and/or drinking water is associated with increased risk of several adverse outcomes including cancers of the skin, bladder and lung. The CONTAM Panel used the benchmark dose lower confidence limit based on a benchmark response (BMR) of 5% (relative increase of the background incidence after adjustment for confounders, BMDL05) of 0.06 μg iAs/kg bw per day obtained from a study on skin cancer as a Reference Point (RP). Inorganic As is a genotoxic carcinogen with additional epigenetic effects and the CONTAM Panel applied a margin of exposure (MOE) approach for the risk characterisation. In adults, the MOEs are low (range between 2 and 0.4 for mean consumers and between 0.9 and 0.2 at the 95th percentile exposure, respectively) and as such raise a health concern despite the uncertainties.

A Clinical Perspective on Arsenic Exposure and Development of Atherosclerotic Cardiovascular Disease

Cardiovascular risk has traditionally been defined by modifiable and non-modifiable risk factors, such as tobacco use, hyperlipidemia, and family history. However, chemicals and pollutants may also play a role in cardiovascular disease (CVD) risk. Arsenic is a naturally occurring element that is widely distributed in the Earth's crust. Inorganic arsenic (iAs) has been implicated in the pathogenesis of atherosclerosis, with chronic high-dose exposure to iAs (> 100 µg/L) being linked to CVD; however, whether low-to-moderate dose exposures of iAs (< 100 µg/L) are associated with the development of CVD is unclear. Due to limitations of the existing literature, it is difficult to define a threshold for iAs toxicity. Studies demonstrate that the effect of iAs on CVD is far more complex with influences from several factors, including diet, genetics, metabolism, and traditional risk factors such as hypertension and smoking. In this article, we review the existing data of low-to-moderate dose iAs exposure and its effect on CVD, along with highlighting the potential mechanisms of action.

Association between exposure to arsenic and the risk of cardiovascular disease: Potential role of vascular endothelial injury

In this study, we investigated the risk of cardiovascular disease (CVD) in individuals exposed to arsenic (As) and to identify potential biomarkers. The results revealed that the FRS was positively correlated with the MMA content and MMA% but negatively correlated with the DMA% and SMI, while the AIP index was positively correlated with the DMA, MMA, MMA%, iAs, tAs and As3+ content. In addition, ADMA was positively correlated with MMA and MMA% and negatively correlated with the SMI and DMA%. Regression models showed that ADMA and ICAM1 were positively correlated with CVD risk. Mediation analysis indicated that ADMA and ICAM1 mediated the association between As exposure and CVD risk. In conclusion, the risk of CVD is higher in residents previously exposed As. Endothelial injury appears to mediate the increased risk of As-induced CVD, and both ADMA and ICAM1 may serve as potential biomarkers for the early identification of this process.

Arterial Stiffness as a Predictor of the Index of Atherosclerotic Cardiovascular Disease in Hypertensive Patients

OBJECTIVE

The aim of this study was to evaluate the predictive value of carotid-femoral pulse wave velocity (cfPWV) and cardiovascular disease in the hypertensive population in China and to determine the specific cfPWV cut-off value for assessing future cardiovascular disease (CVD) risk.

METHODS

This cross-sectional study included 630 hospital patients with primary hypertension and multiple cardiovascular risk factors or complications involving damage to clinical target organs. The study was conducted between July 2007 and October 2008. Atherosclerotic cardiovascular disease (ASCVD) risk calculations were computed according to criteria presented by the American College of Cardiology and the American Heart Association. Patients were stratified by a predefined risk threshold of 10% and divided into two groups: ASCVD ≥ 10% or ASCVD < 10%. cfPWV was used as a marker of arterial stiffness. A receiver operating characteristics (ROC) curve was applied to establish the optimal cfPWV cut-off point to differentiate between participants with and without ASCVD risk.

RESULTS

In the study cohort of 630 patients (age 63.55.2 ± 8.6 years, 61.7% male) with primary hypertension, the pressure indices (augmented pressure, augmentation index [AIx], aortic pulse pressure, aortic systolic pressure [SBP]) and Framingham Risk Scores (FRS) were greater in females than in males (p < 0.001); ASCVD risk scores and peripheral diastolic pressure (DBP) were higher in males (p < 0.05). All hemodynamic indices showed a significant positive correlation with ASCVD risk scores and FRS; AIx was not correlated with ASCVD risk scores. In multivariate logistic analysis, cfPWV was significantly associated with ASCVD risk (OR: 1.324, 95% confidence interval: 1.119-1.565, p < 0.001) after adjusting for age, gender, smoking, body mass index, total cholesterol, fasting blood glucose, antihypertensive treatment, statin treatment, and DBP. In the ROC analysis, the area under the curve was 0.758 and 0.672 for cfPWV and aortic SBP (p < 0.001 and p < 0.001, respectively); the optimal critical value of cfPWV and aortic SBP was 12.45 m/s (sensitivity 63.2%, specificity 77.8%) and 124.5 mmHg (sensitivity 63.9%, specificity 65.3%).

CONCLUSIONS

cfPWV is significantly correlated with the risk of ASCVD. The best cut-off value of cfPWV for assessing future CVD risk in the hypertensive population in China is 12.45 m/s.

Development and application of an evidence-based directed acyclic graph to evaluate the associations between metal mixtures and cardiometabolic outcomes

Objectives

Specifying causal models to assess relationships among metal mixtures and cardiometabolic outcomes requires evidence-based models of the causal structures; however, such models have not been previously published. The objective of this study was to develop and evaluate a directed acyclic graph (DAG) diagraming metal mixture exposure and cardiometabolic outcomes.

Methods

We conducted a literature search to develop the DAG of metal mixtures and cardiometabolic outcomes. To evaluate consistency of the DAG, we tested the suggested conditional independence statements using linear and logistic regression analyses with data from the San Luis Valley Diabetes Study (SLVDS; n=1795). We calculated the proportion of statements supported by the data and compared this to the proportion of conditional independence statements supported by 1,000 DAGs with the same structure but randomly permuted nodes. Next, we used our DAG to identify minimally sufficient adjustment sets needed to estimate the association between metal mixtures and cardiometabolic outcomes (i.e., cardiovascular disease, fasting glucose, and systolic blood pressure). We applied them to the SLVDS using Bayesian kernel machine regression, linear mixed effects, and Cox proportional hazards models.

Results

From the 42 articles included in the review, we developed an evidence-based DAG with 74 testable conditional independence statements (43 % supported by SLVDS data). We observed evidence for an association between As and Mn and fasting glucose.

Conclusions

We developed, tested, and applied an evidence-based approach to analyze associations between metal mixtures and cardiometabolic health.

Arsenic exposure promotes the emergence of cardiovascular diseases

A large number of studies conducted in the past decade 2010-2020 refer to the impact of arsenic (As) exposure on cardiovascular risk factors. The arsenic effect on humans is complex and mainly depends on the varying individual susceptibilities, its numerous toxic expressions and the variation in arsenic metabolism between individuals. In this review we present relevant data from studies which document the association of arsenic exposure with various biomarkers, the effect of several genome polymorphisms on arsenic methylation and the underling molecular mechanisms influencing the cardiovascular pathology. The corresponding results provide strong evidence that high and moderate-high As intake induce oxidative stress, inflammation and vessel endothelial dysfunction that are associated with increased risk for cardiovascular diseases (CVDs) and in particular hypertension, myocardial infarction, carotid intima-media thickness and stroke, ventricular arrhythmias and peripheral arterial disease. In addition, As exposure during pregnancy implies risks for blood pressure abnormalities among infants and increased mortality rates from acute myocardial infarction during early adulthood. Low water As concentrations are associated with increased systolic, diastolic and pulse pressure, coronary heart disease and incident stroke. For very low As concentrations the relevant studies are few. They predict a risk for myocardial infarction, stroke and ischemic stroke and incident CVD, but they are not in agreement regarding the risk magnitude.

miRNA-21, which disrupts metabolic reprogramming to facilitate CD4+ T cell polarization toward the Th2 phenotype, accelerates arsenite-induced hepatic fibrosis

Elevated levels of arsenic may be present in groundwater, and long-term exposure to arsenic increases hepatic fibrosis. T helper 2 (Th2) cells are involved in the fibrotic cascade, and cell metabolism is a regulatory factor participating in CD4⁺ T cell differentiation and function. However, the mechanism for Th2 cell regulation of arsenite-induced hepatic fibrosis is not fully understood. In present study, for arsenite-fed mice, activated hepatic stellate cells may be involved in the infiltration of CD4⁺ T cells, accompanied by up-regulation of GATA3, a transcription factor, and IL-13, the major Th2 cytokine. Exposed to arsenite, Jurkat cells had increased aerobic glycolysis to promote the cell cycle and cell proliferation. Further, this process elevated levels of marker molecules, including those of the Th2 paradigm characterized by GATA3, IL-4, and IL-13. LX-2 cells were activated when treated with culture medium from Jurkat cells exposed to arsenite. miR-21 may be a therapeutic target for arsenite-induced hepatic fibrosis. In vitro, miR-21 knock-down caused inhibition of the PTEN/PI3K/AKT pathway induced by arsenite. It also reversed the elevated glycolysis and the accelerated cell cycle and cell proliferation. Indeed, this alteration led to diminished expression of GATA3, IL-4, and IL-13 in T cells differentiated under Th2 conditions, which inhibits activation of LX-2 cells. Consistent with the results in vitro, miR-21 knock-out in mice reversed hepatic fibrosis and attenuated the levels of GATA3 and IL-13 induced by arsenite. These findings indicate that miR-21 regulates the glycolysis of CD4⁺ T cells through the PTEN/PI3K/AKT pathway to accelerate the cell cycle, thereby facilitating CD4⁺ T cell polarization toward Th2 and releasing the fibrogenic factor IL-13, which participates in arsenite-associated hepatic fibrosis. Inhibition of Th2 polarization of CD4⁺T cells or miR-21 could be a therapeutic strategy to combat hepatic fibrosis caused by exposure to arsenic.

The interplay between exposure to PAHs and MTHFR C677T polymorphism on cardiovascular risk biomarkers in Mexican women

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Environmental and genetic factors are recognized as risk determinants in the onset and development of CVDs. However, the interaction between both factors on CVDs risk is not still completely clarified. Therefore, the objective of this study was to evaluate the effect of the interaction between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and polycyclic aromatic hydrocarbon (PAH) exposure (gene-environment interaction) on cardiovascular risk biomarkers in Mexican women. A cross-sectional study was completed with the participation of 390 healthy women. For all enrolled women, anthropometric measurements, serum biochemical analyses, atherogenic indexes, and serum concentrations of biomolecules used as CVD risk biomarkers were obtained. 1-Hydroxypyrene (1-OHP) was measured in urine, as an exposure biomarker of PAHs. The mean urinary level of 1-OHP in the assessed population was 1.23 ± 1.40 μmol/mol creatinine. The allelic frequency (MTHFR C677T polymorphism) identified in the registered individuals was 68.0% for the mutant allele (T-allele). Significant positive associations were detected between urinary 1-OHP levels and serum asymmetric dimethylarginine (ADMA) concentrations (p < 0.05) and atherogenic index of plasma (AIP) values (p < 0.05). Also, women with the TT genotype of the MTHFR C677T enzyme have the highest serum ADMA levels (p < 0.05) and AIP values (p < 0.05) compared to women grouped as CC genotype and CT genotype. Besides, the findings in this study suggest an interaction between environmental (PAHs exposure) and genetic (MTHFR C677T polymorphism) factors on cardiovascular risk markers (ADMA and AIP). According to the usefulness of AIP and ADMA, an increased cardiovascular risk is notable in highly exposed individuals to PAHs with the polymorphic genotype (TT) of the MTHFR enzyme. Therefore, intervention programs in the target communities are required to diminish the cardiovascular risk of the assessed individuals.

The hypermethylation of FOXP3 gene as an epigenetic marker for the identification of arsenic poisoning risk

Background and Purpose: Arsenic exposure can lead to skin lesions and multiple organ damage, which are not easily reversible and for which there is no effective therapeutics. Identification of reliable epigenetic markers is essential for early recognition of arsenic poisoning risk. Anomalous DNA methylation of immune homeostasis regulator FOXP3 is a critical mechanism for triggering arsenic poisoning. This study aims to explore the value of FOXP3 methylation in the identification of arsenic poisoning risk.Methods: 88 arsenic poisoning subjects and 41 references were recruited. Urinary arsenic contents and FOXP3 methylation in PBLCs was measured by ICP-MS and pyrosequencing, respectively.Results: The results showed that the elevated FOXP3 methylation in PBLCs were associated with the increased levels of urinary arsenic and were positively associated with the increased risk of arsenic poisoning and its progression. The result of mediation analysis revealed that 24.3% of the effect of arsenic exposure on the risk of arsenic poisoning was mediated by increased FOXP3 methylation. Additionally, we constructed a nomogram model with FOXP3 methylation as an epigenetic predictor to assess the probability of individual arsenic poisoning. The model showed a robust ability in the discrimination of arsenic poisoning risk, with an area under receiver operating characteristics curve of 0.897(0.845-0.949) and more than 70% accuracy. The calibration curves and the Harrell concordance index showed that the consistency rate between the probability predicted by the nomogram model and the actual probability is 89.7%.Conclusions: Taken together, we found the great potential of FOXP3 methylation for the identification of arsenic poisoning risk and provided a new approach to the application of epigenetic markers in accurately quantifying the risk of adverse outcomes.

Toxic Metals and Subclinical Atherosclerosis in Carotid, Femoral, and Coronary Vascular Territories: The Aragon Workers Health Study

OBJECTIVE

Studies evaluating the association of metals with subclinical atherosclerosis are mostly limited to carotid arteries. We assessed individual and joint associations of nonessential metals exposure with subclinical atherosclerosis in 3 vascular territories. Approach and Results: One thousand eight hundred seventy-three Aragon Workers Health Study participants had urinary determinations of inorganic arsenic species, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten. Plaque presence in carotid and femoral arteries was determined by ultrasound. Coronary Agatston calcium score ≥1 was determined by computed tomography scan. Median arsenic, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten levels were 1.83, 1.98, 0.27, 1.18, 0.05, 9.8, 0.03, 0.66, and 0.23 μg/g creatinine, respectively. The adjusted odds ratio (95% CI) for subclinical atherosclerosis presence in at least one territory was 1.25 (1.03-1.51) for arsenic, 1.67 (1.22-2.29) for cadmium, and 1.26 (1.04-1.52) for titanium. These associations were driven by arsenic and cadmium in carotid, cadmium and titanium in femoral, and titanium in coronary territories and mostly remained after additional adjustment for the other relevant metals. Titanium, cadmium, and antimony also showed positive associations with alternative definitions of increased coronary calcium. Bayesian Kernel Machine Regression analysis simultaneously evaluating metal associations suggested an interaction between arsenic and the joint cadmium-titanium exposure.

CONCLUSIONS

Our results support arsenic and cadmium and identify titanium and potentially antimony as atherosclerosis risk factors. Exposure reduction and mitigation interventions of these metals may decrease cardiovascular risk in individuals without clinical disease.

Joint Associations of Multiple Dietary Components With Cardiovascular Disease Risk: A Machine-Learning Approach

The human diet consists of a complex mixture of components. To realistically assess dietary impacts on health, new statistical tools that can better address nonlinear, collinear, and interactive relationships are necessary. Using data from 1,928 healthy participants in the Coronary Artery Risk Development in Young Adults (CARDIA) cohort (1985-2006), we explored the association between 12 dietary factors and 10-year predicted risk of atherosclerotic cardiovascular disease (ASCVD) using an innovative approach, Bayesian kernel machine regression (BKMR). Employing BKMR, we found that among women, unprocessed red meat was most strongly related to the outcome: An interquartile range increase in unprocessed red meat consumption was associated with a 0.07-unit (95% credible interval: 0.01, 0.13) increase in ASCVD risk when intakes of other dietary components were fixed at their median values (similar results were obtained when other components were fixed at their 25th and 75th percentile values). Among men, fruits had the strongest association: An interquartile range increase in fruit consumption was associated with -0.09-unit (95% credible interval (CrI): -0.16, -0.02), -0.10-unit (95% CrI: -0.16, -0.03), and -0.11-unit (95% CrI: -0.18, -0.04) lower ASCVD risk when other dietary components were fixed at their 25th, 50th (median), and 75th percentile values, respectively. Using BKMR to explore the complex structure of the total diet, we found distinct sex-specific diet-ASCVD relationships and synergistic interaction between whole grain and fruit consumption.

microRNA-21, via the HIF-1α/VEGF signaling pathway, is involved in arsenite-induced hepatic fibrosis through aberrant cross-talk of hepatocytes and hepatic stellate cells

Long-term exposure to arsenic, a widely distributed environmental toxicant, may result in damage to various organs, including the liver. Mice exposed chronically to arsenite developed hepatic damage, inflammation, and fibrosis, as well as increased levels of microRNA-21 (miR-21) and hypoxia-inducible factor (HIF)-1α. The levels of miR-21 and HIF-1α were also enhanced in primary hepatocytes and L-02 cells exposed to arsenite. The culture media from these cells induced the activation of hepatic stellate cells (HSCs), as demonstrated by up-regulation of the protein levels of α-smooth muscle actin (α-SMA) and collagen1A2 (COL1A2) and by increased activity in gel contractility assays. For L-02 cells, knockdown of miR-21 blocked the arsenite-induced up-regulation of HIF-1α and vascular endothelial growth factor (VEGF), which prevented the activation of LX-2 cells induced by medium from arsenite-exposed L-02 cells. However, these effects were reversed by down-regulation of von Hippel Lindau protein (pVHL). In arsenite-treated L-02 cells, miR-21 knockdown elevated the levels of ubiquitination and accelerated the degradation of HIF-1α via pVHL. In the livers of miR-21^-/- mice exposed chronically to arsenite, there were less hepatic damage, lower fibrosis, lower levels of HIF-1α and VEGF, and higher levels of pVHL than for wild-type mice. In summary, we propose that miR-21, acting via the HIF-1α/VEGF signaling pathway, is involved in arsenite-induced hepatic fibrosis through mediating aberrant cross-talk of hepatocytes and HSCs. The findings provide evidence relating to the pathogenesis of hepatic fibrosis induced by exposure to arsenic.

Positive Association of Cardiovascular Disease (CVD) with Chronic Exposure to Drinking Water Arsenic (As) at Concentrations below the WHO Provisional Guideline Value: A Systematic Review and Meta-Analysis

To the best of our knowledge, a dose-response meta-analysis of the relationship between cardiovascular disease (CVD) and arsenic (As) exposure at drinking water As concentrations lower than the WHO provisional guideline value (10 µg/L) has not been published yet. We conducted a systematic review and meta-analyses to estimate the pooled association between the relative risk of each CVD endpoint and low-level As concentration in drinking water both linearly and non-linearly using a random effects dose-response model. In this study, a significant positive association was found between the risks of most CVD outcomes and drinking water As concentration for both linear and non-linear models (p-value for trend < 0.05). Using the preferred linear model, we found significant increased risks of coronary heart disease (CHD) mortality and CVD mortality as well as combined fatal and non-fatal CHD, CVD, carotid atherosclerosis disease and hypertension in those exposed to drinking water with an As concentration of 10 µg/L compared to the referent (drinking water As concentration of 1 µg/L) population. Notwithstanding limitations included, the observed significant increased risks of CVD endpoints arising from As concentrations in drinking water between 1 µg/L and the 10 µg/L suggests further lowering of this guideline value should be considered.

Association of Arsenic Exposure With Cardiac Geometry and Left Ventricular Function in Young Adults

BACKGROUND

Arsenic exposure has been related to numerous adverse cardiovascular outcomes. The aim of this study was to investigate the cross-sectional and prospective association between arsenic exposure with echocardiographic measures of left ventricular (LV) geometry and functioning.

METHODS

A total of 1337 young adult participants free of diabetes mellitus and cardiovascular disease were recruited from the SHFS (Strong Heart Family Study). The sum of inorganic and methylated arsenic concentrations in urine (ΣAs) at baseline was used as a biomarker of arsenic exposure. LV geometry and functioning were assessed using transthoracic echocardiography at baseline and follow-up.

RESULTS

Mean follow-up was 5.6 years, and median (interquartile range) of ΣAs was 4.2 (2.8-6.9) µg/g creatinine. Increased arsenic exposure was associated with prevalent LV hypertrophy, with an odds ratio (95% CI) per a 2-fold increase in ΣAs of 1.47 (1.05-2.08) in all participants and of 1.58 (1.04-2.41) among prehypertensive or hypertensive individuals. Measures of LV geometry, including LV mass index, left atrial systolic diameter, interventricular septum, and LV posterior wall thickness, were positively and significantly related to arsenic exposure. Among measures of LV functioning, stroke volume, and ejection fraction were associated with arsenic exposure.

CONCLUSIONS

Arsenic exposure was related to an increase in LV wall thickness and LV hypertrophy in young American Indians with a low burden of cardiovascular risk factors. The relationship was stronger in participants with prehypertension or hypertension, suggesting that potential cardiotoxic effects of arsenic might be more pronounced in individuals already undergoing cardiovascular adaptive mechanisms following elevated systemic blood pressure.

Chronic Arsenic Exposure Induces Oxidative Stress and Perturbs Serum Lysolipids and Fecal Unsaturated Fatty Acid Metabolism

Chronic arsenic exposure from drinking water is a global public health issue, which is associated with numerous human diseases and influences millions of people worldwide. The effects of arsenic exposure to the metabolic networks remain elusive. Here, we exposed female C57BL/6J mice to 1 ppm inorganic arsenic in drinking water for 3 months to investigate how arsenic exposure perturbs serum and fecal metabolic profiles. We found decreased levels of serum compounds with antioxidative activities in arsenic-treated mice, in accordance with elevated oxidative stress indicated by higher urinary 8-oxo-2'-deoxyguanosine (8-oxo-dG) levels. Moreover, the levels of multiple lysophosphatidylcholines (lysoPCs) were significantly increased in the sera of arsenic-exposed mice, including lysoPC (O-18:0), lysoPC (20:3), lysoPC (18:1), and lysoPC (22:6). Arsenic exposure perturbed the levels of several key polyunsaturated fatty acids (PUFAs) in the fecal samples in concert with alterations in related microbial pathways. Additionally, changes in the abundances of many functional metabolites, together with decreased levels of amino acids, were found in the fecal samples of arsenic-treated mice. By delineating the impact of arsenic exposure on the metabolic profiles, the findings may provide new biomarkers and mechanistic insights into arsenic-associated diseases.

Sodium arsenite exposure impairs B cell proliferation and enhances vascular inflammation in Plasmodium berghei mouse model

Arsenic exposure has been linked to an impaired immune response and inflammation. Our study investigated the effects of sodium arsenite on host immune response and vascular inflammation during malarial infection. Mice were divided into three groups: control (C), Plasmodium berghei infection (I) and sodium arsenite exposure with Plasmodium berghei infection (As-I). The results showed that splenocyte proliferation stimulated by lipopolysaccharide (LPS) and pokeweed mitogen (PWM) was suppressed in the I group, and the suppression was more pronounced in the As-I group, suggesting that acquired immunity in infected mice was worsening following arsenic exposure. ICAM-1, an adhesion protein involved in parasite-infected red blood cell (iRBC) binding to endothelium, and HIF-1α, a hypoxia marker protein in the descending aorta, were increased in the As-I group compared to the I group. Collectively, our results suggest that arsenic may increase host susceptibility to malaria through suppression of B cell proliferation and enhancement of adhesion between iRBC and endothelium by increasing ICAM-1.

Arsenic exposure and risk of nonalcoholic fatty liver disease (NAFLD) among U.S. adolescents and adults: an association modified by race/ethnicity, NHANES 2005-2014

BACKGROUND

While associated with obesity, the cause of the rapid rise in prevalence of nonalcoholic fatty liver disease (NAFLD) in children, which is highest among Hispanics, is not well understood. Animal experiments have demonstrated that arsenic exposure contributes to liver injury. Our objective was to examine the association between arsenic exposure and NAFLD in humans and to determine if race/ethnicity modifies the association.

METHODS

Urinary inorganic arsenic concentrations among those ≥12 years in the National Health and Nutrition Examination Survey, 2005-2014 were used to assess the cross-sectional association with serum alanine aminotransferase (ALT) levels, a marker of liver dysfunction. We excluded high alcohol consumers (>4-5 drinks/day; n = 939), positive hepatitis B or C (n = 2330), those missing body mass index (n = 100) and pregnant women (n = 629) for a final sample of 8518. Arsenic was measured using liquid chromatography coupled with mass spectrometry and ALT was measured using standard methods. Sampling weights were used to obtain national estimates. Due to lack of normality, estimates were log transformed and are presented as geometric means. Logistic regression models controlling for age, sex, income, and weight category estimate adjusted odd ratios (aOR) of elevated ALT by quartile of arsenic and tested for effect modification by race/ethnicity and weight. Elevated ALT was defined as >25 IU/L and >22 IU/L for boys and girls ≤17 years, respectively and >30 IU/L and >19 IU/L for men and women, respectively.

RESULTS

Among all, aOR of elevated ALT were higher among those in the highest vs. lowest arsenic quartile (referent), 1.4 (95% confidence interval [CI]: 1.1, 1.7) with a borderline significant interaction (p = 0.07) by race/ethnicity but not weight (p = 0.4). In analysis stratified by race/ethnicity, aOR of elevated ALT among those in the 4th quartile were higher among Mexican Americans, 2.0 (CI: 1.3, 3.1) and non-Hispanic whites only, aOR 1.4 (CI: 1.1, 1.8) despite the fact that obesity prevalence was highest among non-Hispanic blacks.

CONCLUSIONS

Our findings demonstrate a positive association between urinary arsenic exposure and risk of NAFLD among U.S. adolescents and adults that is highest among Mexican Americans and among those obese, regardless of race/ethnicity.

Influence on serum asymmetric dimethylarginine (ADMA) concentrations of human paraoxonase 1 polymorphism (Q192R) and exposure to polycyclic aromatic hydrocarbons (PAHs) in Mexican women, a gene-environment interaction

It has been demonstrated that Cardiovascular Diseases (CVD) are a consequence of the combination of genetic and environmental factors and/or the interaction between them. Therefore, the aim of this study was to evaluate the impact of polycyclic aromatic hydrocarbon (PAHs) exposure and PON1 Q192R polymorphism (genetic susceptibility) on serum asymmetric dimethylarginine (ADMA) levels in Mexican women (n = 206). Urinary 1-hydroxypyrene concentrations (1-OHP; exposure biomarker for PAHs) were quantified using a high-performance liquid chromatography technique, PON1 Q192R polymorphism was genotyped using TaqMan probes and serum ADMA concentrations were evaluated using a commercially available ELISA kit. Urinary 1-OHP levels detected in this study ranged from 0.07 to 9.37 μmol/mol of creatinine (0.13-18.0 μg/g of creatinine). Regarding allele frequency (PON1 Q192R polymorphism), the 192Q-allele frequency was 0.43 and for the 192R-allele it was 0.57. In relation to serum ADMA levels, the levels ranged from 0.06 to 1.46 μmol/L. Moreover, multiple linear regression analysis was performed and associations between urinary 1-OHP levels (β = 0.05, p = 0.002), PON1 Q192R polymorphism (β = 0.04, p = 0.003) and serum ADMA concentrations were found. Besides, an interaction (gene-environment interaction) of both independent variables (1-OHP and PON1 polymorphism) on serum ADMA levels was found (β = 0.04, p = 0.02) in the constructed multiple linear model. Therefore, according to the significance of this research, it is necessary to execute health programs to reduce cardiovascular risk in the assessed population.