Levels of a mixture of heavy metals in blood and urine and all-cause, cardiovascular disease and cancer mortality: A population-based cohort study

Association of Urinary Metals With Cardiovascular Disease Incidence and All-Cause Mortality in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Exposure to metals has been associated with cardiovascular disease (CVD) end points and mortality, yet prospective evidence is limited beyond arsenic, cadmium, and lead. In this study, we assessed the prospective association of urinary metals with incident CVD and all-cause mortality in a racially diverse population of US adults from MESA (the Multi-Ethnic Study of Atherosclerosis).

METHODS

We included 6599 participants (mean [SD] age, 62.1 [10.2] years; 53% female) with urinary metals available at baseline (2000 to 2001) and followed through December 2019. We used Cox proportional hazards models to estimate the adjusted hazard ratio and 95% CI of CVD and all-cause mortality by baseline urinary levels of cadmium, tungsten, and uranium (nonessential metals), and cobalt, copper, and zinc (essential metals). The joint association of the 6 metals as a mixture and the corresponding 10-year survival probability was calculated using Cox Elastic-Net.

RESULTS

During follow-up, 1162 participants developed CVD, and 1844 participants died. In models adjusted by behavioral and clinical indicators, the hazard ratios (95% CI) for incident CVD and all-cause mortality comparing the highest with the lowest quartile were, respectively: 1.25 (1.03, 1.53) and 1.68 (1.43, 1.96) for cadmium; 1.20 (1.01, 1.42) and 1.16 (1.01, 1.33) for tungsten; 1.32 (1.08, 1.62) and 1.32 (1.12, 1.56) for uranium; 1.24 (1.03, 1.48) and 1.37 (1.19, 1.58) for cobalt; 1.42 (1.18, 1.70) and 1.50 (1.29, 1.74) for copper; and 1.21 (1.01, 1.45) and 1.38 (1.20, 1.59) for zinc. A positive linear dose-response was identified for cadmium and copper with both end points. The adjusted hazard ratios (95% CI) for an interquartile range (IQR) increase in the mixture of these 6 urinary metals and the corresponding 10-year survival probability difference (95% CI) were 1.29 (1.11, 1.56) and -1.1% (-2.0, -0.05) for incident CVD and 1.66 (1.47, 1.91) and -2.0% (-2.6, -1.5) for all-cause mortality.

CONCLUSIONS

This epidemiological study in US adults indicates that urinary metal levels are associated with increased CVD risk and mortality. These findings can inform the development of novel preventive strategies to improve cardiovascular health.

The role of mitochondrial dysfunction in the association between trace metals and QTc prolongation in the aged population

This study delves into the relationship between environmental metal exposure and QT interval corrected for heart rate (QTc) prolongation, a critical marker for cardiovascular risk in the elderly. Although the interplay between metal exposure and QTc prolongation is important for predicting sudden cardiac death, it remains underexplored. Our analysis of 6478 participants from the Shenzhen aging-related disorder cohort involved measuring urinary concentrations of 22 trace metals and using mitochondrial DNA copy number (mtDNA-CN) as an indicator of mitochondrial dysfunction. Utilizing Bayesian kernel machine regression, and structural equation modeling, we assessed the effects of mixed trace metals on QTc prolongation. Our findings indicated a direct association between certain metals (Sb, Cu, Zn) and a 7 % increase in QTc prolongation risk, while Li, V, and Rb were associated with a 5 % reduction in risk. Elevated levels of V, Ti, and Cr corresponded to higher mtDNA-CN. Notably, restricted cubic splines revealed a U-shaped, nonlinear relationship between mtDNA-CN and QTc prolongation. After adjusting for metal exposure, an inverse correlation was observed between mtDNA-CN and QTc prolongation, suggesting mitochondrial dysfunction as a partial mediator.

Investigating how blood cadmium levels influence cardiovascular health scores across sexes and dose responses

Background

The association between exposure to cadmium (Cd) and cardiovascular health (CVH) has received considerable scientific interest. However, findings thus far have been inconclusive, particularly regarding sex-specific effects and dose-response relationships. The aim of our study was to investigate the relationships of blood Cd levels with the overall and component CVH scores.

Methods

We used data from the 2011-2018 NHANES to assess CVH using indicators such as BMI, blood pressure, lipid profiles, glucose levels, diet, physical activity, nicotine use, and sleep quality, each rated on a 0-100 scale. The overall CVH score was calculated as the average of these indicators. We employed both multiple linear and restricted cubic spline analyses to examine the relationship between blood Cd levels and CVH scores, including nonlinear patterns and subgroup-specific effects.

Results

Our analysis revealed that higher blood Cd levels were associated with lower overall CVH, nicotine exposure, sleep, and diet scores, with nonlinear decreases observed in overall CVH and nicotine exposure scores at specific thresholds (-1.447 and -1.752 log μg/dL, respectively). Notably, sex differences were evident; females experienced more adverse effects of Cd on CVH and lipid scores, while in males, Cd exposure was positively correlated with BMI, a link not observed in females.

Conclusion

Our study highlights the complex interplay between blood Cd levels and various aspects of CVH, revealing significant dose-response relationships and sex disparities. These findings enhance our understanding of the biobehavioral mechanisms linking Cd exposure to cardiovascular risk.

Associations of serum lead, cadmium, and mercury concentrations with all-cause and cause-specific mortality among individuals with cardiometabolic multimorbidity

Epidemiological evidence indicates an association between exposure to toxic metals and the occurrence of cardiometabolic diseases (CMDs). However, the impact of exposure to harmful metallic elements, such as lead (Pb), cadmium (Cd), and mercury (Hg), on mortality in individuals with cardiometabolic multimorbidity (CMM) remains uncertain. Therefore, in this study, we analyzed data from 4139 adults diagnosed with CMM from the National Health and Nutrition Examination Survey 1999-2016. CMM was defined as the presence of at least two CMDs (hypertension, diabetes, stroke, and coronary artery disease). Over an average follow-up period of 9.0 years, 1379 deaths from all causes, 515 deaths related to cardiovascular disease (CVD), and 215 deaths attributable to cancer were recorded. After adjusting for potential covariates, serum Pb concentrations were not associated with all-cause, CVD, or cancer mortality. Participants exposed to Cd had an elevated risk of all-cause mortality (hazard ratio [HR], 1.23; 95 % CI, 1.16-1.30), CVD-related mortality (HR, 1.23; 95 % CI, 1.12-1.35), and cancer-related mortality (HR, 1.29; 95 % CI, 1.13-1.47). Participants with serum Hg levels in the highest quantile had lower risks of all-cause (HR, 0.64; 95 % CI, 0.52-0.80) and CVD-related (HR, 0.62; 95 % CI, 0.44-0.88) mortality than did those in the lowest quantile. Stratified analyses revealed significant interactions between serum Cd concentrations and age for CVD-related mortality (P for interaction =0.011), indicating that CMM participants aged < 60 years who were exposed to Cd were at a greater risk of CVD-related mortality. A nonlinear relationship was observed between serum Cd concentrations and all-cause (P for nonlinear relationship = 0.012) and CVD-related (P for nonlinear relationship < 0.001) mortality. Minimizing Cd exposure in patients with CMM may help prevent premature death.

Preparation of 6-Amino-N-hydroxyhexanamide-Modified Porous Chelating Resin for Adsorption of Heavy Metal Ions

The pollution of water bodies by heavy metal ions has recently become a global concern. In this experiment, a novel chelating resin, D851-6-AHHA, was synthesized by grafting 6-amino-N-hydroxyhexanamide (6-AHHA) onto the (-CH2N-(CH2COOH)2) group of the D851 resin, which contained a hydroxamic acid group, amide group, and some carboxyl groups. This resin was developed for the purpose of removing heavy metal ions, such as Cr(III) and Pb(II), from water. The findings from static adsorption experiments demonstrated the remarkable adsorption effectiveness of D851-6-AHHA resin towards Cr(III) and Pb(II). Specifically, the maximum adsorption capacities for Cr(III) and Pb(II) were determined to be 91.50 mg/g and 611.92 mg/g, respectively. Furthermore, the adsorption kinetics of heavy metal ions by D851-6-AHHA resin followed the quasi-second-order kinetic model, while the adsorption isotherms followed the Langmuir model. These findings suggest that the adsorption process was characterized by monolayer chemisorption. The adsorption mechanism of D851-6-AHHA resin was comprehensively investigated through SEM, XRD, FT-IR, and XPS analyses, revealing a high efficiency of D851-6-AHHA resin in adsorbing Cr(III) and Pb(II). Specifically, the (-C(=O)NHOH) group exhibited a notable affinity for Cr(III) and Pb(II), forming stable multi-elemental ring structures with them. Additionally, dynamic adsorption experiments conducted using fixed-bed setups further validated the effectiveness of D851-6-AHHA resin in removing heavy metal ions from aqueous solutions. In conclusion, the experimental findings underscored the efficacy of D851-6-AHHA resin as a highly efficient adsorbent for remediating water bodies contaminated by heavy metal ions.

Sex- and age-specific associations of serum essential elements with diabetes among the Chinese adults: a community-based cross-sectional study

BACKGROUND

Although several studies have found the relationship between essential elements and diabetes, the studies about the association of essential elements with diabetes diagnosed according to an oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) in a sex- and age-specific manner were limited. To investigate the linear and nonlinear relationship of five essential elements including iron (Fe), copper (Cu), Zinc (Zn), magnesium (Mg), and calcium (Ca) with diabetes, fasting plasma glucose (FPG), 2-h postprandial plasma glucose (PPG), and HbA1c and to evaluate the sex- and age-specific heterogeneities in these relationships.

METHODS

A total of 8392 community-dwelling adults were recruited to complete a questionnaire and undergo checkups of anthropometric parameters and serum levels of five metals (Fe, Cu, Zn, Mg, and Ca). The multivariable logistic and linear regression, the restricted cubic spline (RCS) analysis, and subgroup analysis were applied to find the associations between the essential elements and the prevalence of diabetes as well as FPG, PPG, and HbA1c.

RESULTS

In the multivariable logistic regression and multivariable linear regression, serum Cu was positively associated with FPG, PPG, and HbA1c while serum Mg was significantly inversely correlated with FPG, PPG, HbA1c, and diabetes (all P < 0.001). In the RCS analysis, the non-linear relationship of Cu and diabetes (P < 0.001) was found. In the subgroup analysis, stronger positive associations of Cu with diabetes (P for interaction = 0.027) and PPG (P for interaction = 0.002) were found in younger women.

CONCLUSIONS

These findings may lead to more appropriate approaches to essential elements supplementation in people with diabetes of different ages and sexes. However, more prospective cohort and experimental studies are needed to probe the possible mechanism of sex- and age-specific associations between serum essential elements and diabetes.

Association of heavy metals exposure with lower blood pressure in the population aged 8-17 years: a cross-sectional study based on NHANES

Background

The existing evidence regarding the joint effect of heavy metals on blood pressure (BP) in children and adolescents is insufficient. Furthermore, the impact of factors such as body weight, fish consumption, and age on their association remains unclear.

Methods

The study utilized original data from the National Health and Nutrition Examination Survey, encompassing 2,224 children and adolescents with complete information on 12 urinary metals (barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, tungsten, uranium, mercury and arsenic), BP, and core covariates. Various statistical methods, including weighted multiple logistic regression, linear regression, and Weighted Quantile Sum regression (WQS), were employed to evaluate the impact of mixed metal exposure on BP. Sensitivity analysis was conducted to confirm the primary analytical findings.

Results

The findings revealed that children and adolescents with low-level exposure to lead (0.40 μg/L, 95%CI: 0.37, 0.42), mercury (0.38 μg/L, 95%CI: 0.35, 0.42) and molybdenum (73.66 μg/L, 95%CI: 70.65, 76.66) exhibited reduced systolic blood pressure (SBP) and diastolic blood pressure (DBP). Conversely, barium (2.39 μg/L, 95%CI: 2.25, 2.54) showed a positive association with increased SBP. A 25th percentile increase in the WQS index is significantly associated with a decrease in SBP of 0.67 mmHg (95%CI, -1.24, -0.10) and a decrease in DBP of 0.59 mmHg (95% CI, -1.06, -0.12), which remains statistically significant even after adjusting for weight. Furthermore, among individuals who consume fish, heavy metals have a more significant influence on SBP. A 25 percentile increase in the WQS index is significantly associated with a decrease of 3.30 mmHg (95% CI, -4.73, -1.87) in SBP, primarily attributed to mercury (27.61%), cadmium (27.49%), cesium (17.98%), thallium (8.49%). The study also identified a declining trend in SBP among children aged 10-17, whereas children aged 11-18 exhibited lower levels of systolic and diastolic blood pressure, along with a reduced risk of hypertension.

Conclusion

Some heavy metals demonstrate an inverse association with the BP of children and adolescents, particularly notable in groups with fish consumption and older children and adolescents. Future studies are warranted to validate these findings and delve deeper into the interplay of heavy metals.

Assessing the Risk of Heart Attack: A Bayesian Kernel Machine Regression Analysis of Heavy Metal Mixtures

Background

The assessment of heavy metals' effects on human health is frequently limited to investigating one metal or a group of related metals. The effect of heavy metals mixture on heart attack is unknown.

Methods

This study applied the Bayesian kernel machine regression model (BKMR) to the 2011-2016 National Health and Nutrition Examination Survey (NHANES) data to investigate the association between heavy metal mixture exposure with heart attack. 2972 participants over the age of 20 were included in the study.

Results

Results indicate that heart attack patients have higher levels of cadmium and lead in the blood and cadmium, cobalt, and tin in the urine, while having lower levels of mercury, manganese, and selenium in the blood and manganese, barium, tungsten, and strontium in the urine. The estimated risk of heart attack showed a negative association of 0.0030 units when all the metals were at their 25th percentile compared to their 50th percentile and a positive association of 0.0285 units when all the metals were at their 75th percentile compared to their 50th percentile. The results suggest that heavy metal exposure, especially cadmium and lead, may increase the risk of heart attacks.

Conclusions

This study suggests a possible association between heavy metal mixture exposure and heart attack and, additionally, demonstrates how the BKMR model can be used to investigate new combinations of exposures in future studies.

Associations of Blood and Urinary Heavy Metals with Stress Urinary Incontinence Risk Among Adults in NHANES, 2003-2018

People come into contact with heavy metals in various ways in their daily lives. Accumulating evidence shows that toxic metal exposure is hazardous to human health. However, limited information is available regarding the impact of metal mixtures on stress urinary incontinence (SUI). Therefore, we used data from 10,622 adults from the 2003-2018 National Health and Nutrition Examination Survey (NHANES) to investigate the independent and comprehensive association between heavy metal co-exposure and SUI. Among them, 2455 (23.1%) had been diagnosed with SUI, while the rest had no SUI. We evaluated the independent and combined associations of 3 blood metals and 10 urinary metals with SUI risk, along with subgroup analyses according to age and gender. In the single-exposure model, blood cadmium (Cd), lead (Pb), mercury (Hg), urinary Cd, Pb, and cesium (Cs) were found to be positively connected with SUI risk. Moreover, weighted quantile sum (WQS) regression, quantile-based g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) consistently demonstrated blood and urinary metal-mixed exposure were positively associated with the risk of SUI, and emphasized that blood Pb and Cd and urinary Cd and Cs were the main positive drivers, respectively. This association was more pronounced in the young and middle-aged group (20-59 years old) and the female group. Nevertheless, further research is necessary to validate these significant findings.

Association between per- and polyfluoroalkyl substances exposure and prevalence of chronic obstructive pulmonary disease: The mediating role of serum albumin

BACKGROUND

No study has examined the association between per- and polyfluoroalkyl substances (PFAS) exposure and chronic obstructive pulmonary disease (COPD) risk. This study aims to explore this relationship.

METHODS

This study enrolled 4541 individuals who had available data on PFAS, COPD, and covariates from NHANES 2007-2018. Serum PFAS including perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS) were analyzed, because of high detective rates. Considering the skew distribution of PFAS levels, the natural logarithm-transformed PFAS (Ln-PFAS) was used. Logistic regression analysis, restricted cubic spline (RCS), and weighted quantile sum (WQS) regression were performed to explore the single, nonlinear, and mixed effects. A mediating analysis was used to evaluate the mediated effects of albumin.

RESULTS

Individuals with COPD had higher levels of PFHxS, PFNA, PFOA, and PFOS compared to those without COPD. Ln-PFNA (OR males: 1.92, 95 % CI:1.31 to 2.80, P: <0.001; OR females: 1.07, 95 % CI: 0.81 to 1.40, P: 0.636) and ln-PFOA (OR males: 2.17, 95 % CI:1.38 to 3.41, P: <0.001; OR females: 1.49, 95 % CI: 1.08 to 2.05, P: 0.016) were associated with COPD risk especially in males. The interaction between PFNA exposure and sex on COPD risk was significant (P interaction: <0.001). The RCS curve demonstrated the nonlinear relationship between the ln-PFOA (P nonlinear:0.001), ln-PFNA (P nonlinear:0.045), and COPD risk in males. WQS analysis showed mixed PFAS exposure was correlated with COPD risk in males (OR: 1.44, 95 % CI:1.18 to 1.75, P: <0.001). Albumin mediated the relationship between PFOA and COPD (mediated proportion: -17.94 %).

CONCLUSION

This study concludes PFOA and PFNA are linked to a higher COPD risk in males, and serum albumin plays a mediating role in the relationship between PFOA and COPD. Thess findings are beneficial for the prevention of COPD. Further studies are required to explore potential mechanisms.

Association of Blood Copper With the Subclinical Carotid Atherosclerosis: An Observational Study

BACKGROUND

Copper exposure is reported to be associated with increased risk of stroke. However, the association of copper exposure with subclinical carotid atherosclerosis remains unclear.

METHODS AND RESULTS

This observational study included consecutive participants from Xinqiao Hospital between May 2020 and August 2021. Blood metals were measured using inductively coupled plasma mass spectrometry and carotid atherosclerosis was assessed using ultrasound. Modified Poisson regression was performed to evaluate the associations of copper and other metals with subclinical carotid plaque presence. Blood metals were analyzed as categorical according to the quartiles. Multivariable models were adjusted for age, sex, body mass index, education, smoking, drinking, hypertension, diabetes, dyslipidemia, estimated glomerular filtration rate, and coronary artery disease history. Bayesian Kernel Machine Regression was conducted to evaluate the overall association of metal mixture with subclinical carotid plaque presence. One thousand five hundred eighty-five participants were finally enrolled in our study, and carotid plaque was found in 1091 subjects. After adjusting for potential confounders, metal-progressively-adjusted models showed that blood copper was positively associated with subclinical carotid plaque (relative risk according to comparing quartile 4 to quartile 1 was 1.124 [1.021-1.238], relative risk according to per interquartile increment was 1.039 [1.008-1.071]). Blood cadmium and lead were also significantly associated with subclinical carotid plaque. Bayesian Kernel Machine Regression analyses suggested a synergistic effect of copper-cadmium-lead mixture on subclinical carotid plaque presence.

CONCLUSIONS

Our findings identify copper as a novel risk factor of subclinical carotid atherosclerosis and show the potential synergistic proatherogenic effect of copper, cadmium, and lead mixture.

Associations of coal mine dust exposure with arterial stiffness and atherosclerotic cardiovascular disease risk in chinese coal miners

OBJECTIVE

Whether coal mine dust exposure increases cardiovascular diseases (CVDs) risk was rarely explored. Our objective was to examine the association between coal mine dust exposure and cardiovascular risk.

METHODS

We estimated cumulative coal mine dust exposure (CDE) for 1327 coal miners by combining data on workplace dust concentrations and work history. We used brachial-ankle pulse wave velocity (baPWV, a representative indicator of arterial stiffness) and ten-year atherosclerotic cardiovascular disease (ASCVD) risk to assess potential CVD risk, exploring their associations with CDE.

RESULTS

Positive dose-response relationships of CDE with baPWV and ten-year ASCVD risk were observed after adjusting for covariates. Specifically, each 1 standard deviation (SD) increase in CDE was related to a 0.27 m/s (95% CI: 0.21, 0.34) increase in baPWV and a 1.29 (95% CI: 1.14, 1.46) elevation in OR (odds ratio) of risk of abnormal baPWV. Moreover, each 1 SD increase in CDE was associated with a 0.74% (95% CI: 0.63%, 0.85%) increase in scores of ten-year ASCVD and a 1.91 (95% CI: 1.62, 2.26) increase in OR of risk of ten-year ASCVD. When compared with groups unexposed to coal mine dust, significant increase in the risk of arterial stiffness and ten-year ASCVD in the highest CDE groups were detected.

CONCLUSION

The study suggested that cumulative exposure to coal mine dust was associated with elevated arterial stiffness and ten-year ASCVD risk in a dose-response manner. These findings contribute valuable insights for cardiovascular risk associated with coal mine dust.

Association of Metal Exposure with Novel Immunoinflammatory Indicators

Objective: We aimed to investigate the relationship between metal exposure and novel immunoinflammatory indicators. Methods: Data on adults participating in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018 were analyzed. Various statistical models were employed to assess the association between metal exposure and novel immune-inflammation-related indicators. Additionally, the impact of metal exposure on inflammation in different gender populations was explored. Results: This study included 4482 participants, of whom 51.1% were male. Significant correlations were observed among various metals. Both elastic net (ENET) and linear regression models revealed robust associations between cadmium (Cd), cobalt (Co), arsenic (As), mercury (Hg), and immunoinflammatory indicators. Weighted quantile sum (WQS) and Quantile g-computation (Q-gcomp) models demonstrated strong associations between barium (Ba), Co, and Hg and immunoinflammatory indicators. Bayesian kernel machine regression (BKMR) analysis indicated an overall positive correlation between in vivo urinary metal levels and systemic inflammation response index (SIRI) and aggregate index of systemic inflammation (AISI). Furthermore, Co, As, and Hg emerged as key metals contributing to changes in novel immunoinflammatory indicators. Conclusions: Metals exhibit associations with emerging immunoinflammatory indicators, and concurrent exposure to mixed metals may exacerbate the inflammatory response. Furthermore, this relationship varies across gender populations.

The Impact of the Aryl Hydrocarbon Receptor on Antenatal Chemical Exposure-Induced Cardiovascular-Kidney-Metabolic Programming

Early life exposure lays the groundwork for the risk of developing cardiovascular-kidney-metabolic (CKM) syndrome in adulthood. Various environmental chemicals to which pregnant mothers are commonly exposed can disrupt fetal programming, leading to a wide range of CKM phenotypes. The aryl hydrocarbon receptor (AHR) has a key role as a ligand-activated transcription factor in sensing these environmental chemicals. Activating AHR through exposure to environmental chemicals has been documented for its adverse impacts on cardiovascular diseases, hypertension, diabetes, obesity, kidney disease, and non-alcoholic fatty liver disease, as evidenced by both epidemiological and animal studies. In this review, we compile current human evidence and findings from animal models that support the connection between antenatal chemical exposures and CKM programming, focusing particularly on AHR signaling. Additionally, we explore potential AHR modulators aimed at preventing CKM syndrome. As the pioneering review to present evidence advocating for the avoidance of toxic chemical exposure during pregnancy and deepening our understanding of AHR signaling, this has the potential to mitigate the global burden of CKM syndrome in the future.

Association between exposure to multiple metals and stress urinary incontinence in women: a mixture approach

There is limited evidence linking exposure to heavy metals, especially mixed metals, to stress urinary incontinence (SUI). This study aimed to explore the relationship between multiple metals exposure and SUI in women. The data were derived from the National Health and Nutrition Examination Survey (NHANES), 2007-2020. In the study, a total of 13 metals were analyzed in blood and urine. In addition, 5155 adult women were included, of whom 2123 (41.2%) suffered from SUI. The logistic regression model and restricted cubic spline (RCS) were conducted to assess the association of single metal exposure with SUI risk. The Bayesian kernel machine regression (BKMR) and weighted quantile sum (WQS) were used to estimate the combined effect of multiple metals exposure on SUI. First, we observed that blood Pb, Hg and urinary Pb, Cd were positively related to SUI risk, whereas urinary W was inversely related by multivariate logistic regression (all p-FDR < 0.05). Additionally, a significant non-linear relationship between blood Hg and SUI risk was observed by RCS analysis. In the co-exposure models, WQS model showed that exposure to metal mixtures in blood [OR (95%CI) = 1.18 (1.06, 1.31)] and urine [OR (95%CI) = 1.18 (1.03, 1.34)] was positively associated with SUI risk, which was consistent with the results of BKMR model. A potential interaction was identified between Hg and Cd in urine. Hg and Cd were the main contributors to the combined effects. In summary, our study indicates that exposure to heavy metal mixtures may increase SUI risk in women.

Combined exposure to multiple metals on abdominal aortic calcification: results from the NHANES study

Exposure to metals increases the risk of many diseases and has become a public health concern. However, few studies have focused on the effect of metal on abdominal aortic calcification (AAC), especially the combined effects of metal mixtures. In this study, we aim to investigate the combined effect of metals on AAC risk and determine the key components in the multiple metals. We tried to investigate the relationship between multiple metal exposure and AAC risk. Fourteen urinary metals were analyzed with five statistical models as follows: generalized linear regression, weighted quantile sum regression (WQS), quantile g-computation (Qgcomp), and Bayesian kernel machine regression (BKMR) models. A total of 838 participants were involved, of whom 241 (28.8%) had AAC. After adjusting for covariates, in multiple metal exposure logistic regression, cadmium (Cd) (OR = 1.364, 95% CI = 1.035-1.797) was positively associated with AAC risk, while cobalt (Co) (OR = 0.631, 95% CI = 0.438-0.908) was negatively associated with AAC risk. A significant positive effect between multiple metal exposure and AAC risk was observed in WQS (OR = 2.090; 95% CI = 1.280-3.420, P < 0.01), Qgcomp (OR = 1.522, 95% CI = 1.012-2.290, P < 0.05), and BKMR models. It was found that the positive association may be driven primarily by Cd, lead (Pb), uranium (U), and tungsten (W). Subgroups analysis showed the association was more significant in participants with BMI ≥ 25 kg/m2, abdominal obesity, drinking, and smoking. Our study shows that exposure to multiple metals increases the risk of AAC in adults aged ≥ 40 years in the USA and that Cd, Pb, U, and W are the main contributors. The association is stronger in participants who are obese, smoker, or drinker.

Atherogenic Index as a Cardiovascular Biomarker in Mexican Workers from Marginalized Urban Areas Occupationally Exposed to Metals

BACKGROUND

Cardiovascular disease (CVD) is one of the main causes of death and disability worldwide. The etiology of CVD is often associated with multiple risk factors, with environmental factors receiving considerable attention. Individuals with precarious jobs are among the groups most affected by chronic exposure to environmental pollutants.

AIM

This study aimed to evaluate occupational exposure to heavy metals among individuals in precarious job settings and investigate atherogenic indices as biomarkers of cardiovascular risk.

METHODS

A total of 137 workers participated in this cross-sectional study conducted in three work environments in San Luis Potosi, Mexico. Urine and blood samples were collected to assess metal exposure and biochemical profiles, including atherogenic indices.

RESULTS

The results showed that workers in the brick sector exhibited the highest levels of metal exposure, particularly arsenic (44.06 µg/L), followed by stonecutters and garbage collectors (24.7 and 16.9 µg/L, respectively). Similarly, Castelli risk index (CRI) and the atherogenic index of plasma (AIP) were higher in brickmakers (3.883 and 0.499) compared to stonecutters (3.285 and 0.386) and garbage collectors (3.329 and 0.367).

CONCLUSIONS

Evidence of exposure to heavy metals was observed in the three populations, in addition to the fact that individuals with greater exposure to arsenic also exhibited higher CRI and AIP.

Investigating the impact of elevated urinary trace elements on non-alcoholic fatty liver disease using vibration-controlled transient elastography

Introduction

Non-alcoholic fatty liver disease (NAFLD) is a global public health concern. However, limited data are available on urinary trace elements and NAFLD caused by various exposure factors. This study aimed to investigate the relationship between the presence of 16 trace elements in urine and NAFLD using data from the National Health and Nutrition Examination Survey (NHANES).

Methods

By utilizing the NHANES data from 2017 to 2018, 1613 participants who fulfilled the research criteria were identified from the initial pool of 2979 participants with available urine trace element detection data. Among them, 706 individuals had been diagnosed with NAFLD based on a coefficient of attenuation parameter (CAP) value of at least 274 db/m, determined using vibration-controlled transient elastography (VCTE); whereas the remaining 907 participants were classified as non-NAFLD. The data obtained were used to construct univariate and multivariate logistic regression models and restricted cubic spline models (RCS) analyses.

Results

The presence of arsenic, iodine, barium, cesium, molybdenum, lead, tin, and tungsten in the urine of individuals with NAFLD showed a positive correlation with the likelihood of developing NAFLD. The risk of NAFLD had a non-linear dose-dependent relationship with urinary iodine, molybdenum, barium, and cesium. NAFLD was also associated with elevated levels of barium and cesium in urine, which were identified as significant risk factors.

Conclusion

These findings suggest a positive association between exposure to trace elements in the urine and the risk of NAFLD. Specifically, urinary barium and cesium appeared to have the greatest impact on the risk of NAFLD. These results provide novel insights into the diagnosis and treatment of NAFLD.

Associations between patterns of blood heavy metal exposure and health outcomes: insights from NHANES 2011-2016

BACKGROUND

Extensive research has explored the association between heavy metal exposure and various health outcomes, including malignant neoplasms, hypertension, diabetes, and heart diseases. This study aimed to investigate the relationship between patterns of exposure to a mixture of seven heavy metals and these health outcomes.

METHODS

Blood samples from 7,236 adults in the NHANES 2011-2016 studies were analyzed for levels of cadmium, manganese, lead, mercury, selenium, copper, and zinc. Cluster analysis and logistic regression identified three distinct patterns of mixed heavy metal exposure, and their associations with health outcomes were evaluated.

RESULTS

Pattern 1 exhibited higher odds ratios (ORs) for malignancy during NHANES 2011-2012 (OR = 1.33) and 2015-2016 (OR = 1.29) compared to pattern 2. Pattern 3 showed a lower OR for malignancy during NHANES 2013-2014 (OR = 0.62). For hypertension, pattern 1 displayed higher ORs than pattern 2 for NHANES 2011-2012 (OR = 1.26), 2013-2014 (OR = 1.31), and 2015-2016 (OR = 1.41). Pattern 3 had lower ORs for hypertension during NHANES 2013-2014 (OR = 0.72) and 2015-2016 (OR = 0.67). In terms of heart diseases, pattern 1 exhibited higher ORs than pattern 2 for NHANES 2011-2012 (OR = 1.34), 2013-2014 (OR = 1.76), and 2015-2016 (OR = 1.68). Pattern 3 had lower ORs for heart diseases during NHANES 2013-2014 (OR = 0.59) and 2015-2016 (OR = 0.52). However, no significant trend was observed for diabetes. All three patterns showed the strongest association with hypertension among the health outcomes studied.

CONCLUSIONS

The identified patterns of seven-metal mixtures in NHANES 2011-2016 were robust. Pattern 1 exhibited higher correlations with hypertension, heart disease, and malignancy compared to pattern 2, suggesting an interaction between these metals. Particularly, the identified patterns could offer valuable insights into the management of hypertension in healthy populations.

The association between polychlorinated dibenzo-p-dioxin exposure and cancer mortality in the general population: a cohort study

Introduction

Earlier research has indicated that being exposed to polychlorinated dibenzo-p-dioxins (PCDDs) in the workplace can heighten the likelihood of cancer-related deaths. Nevertheless, there is limited information available regarding the connection between PCDD exposure and the risk of cancer mortality in the general population (i.e., individuals not exposed to these substances through their occupation).

Methods

The National Health and Nutrition Examination Survey (NHANES) detected PCDDs in the general population, and the death data were recently updated as of December 31, 2019. We conducted Cox regression analysis and controlled for covariates including age, gender, ethnicity, educational attainment, physical activity, alcohol intake, NHANES survey period, BMI category, cotinine concentration, and household earnings.

Results

After accounting for confounding factors, the findings indicated that for each incremental rise of 1 log unit in 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, there was a 76% rise in the likelihood of death from any cause, with a p value of 0.003. An increase of 1 log unit in the concentration of 1,2,3,4,6,7,8-heptachlorodibenzofuran could potentially lead to a 90% higher risk of cancer mortality, as indicated by a p value of 0.034 and a 95% confidence interval of 0.05-2.43. As the concentrations of 1,2,3,4,6,7,8-heptachlorodibenzofuran increased, the dose-response curve indicated a proportional rise in the risk of cancer mortality, accompanied by a linear p value of 0.044. The sensitivity analysis demonstrated that our findings were resilient.

Discussion

In the general population, an elevated risk of cancer mortality was observed in PCDDs due to the presence of 1,2,3,4,6,7,8-heptachlorodibenzofuran. Mechanistic research is required to further confirm it.

Cytogenotoxicity evaluation of heavy metals detected in extracts and infusion of Baccharis trimera, potential bioaccumulator plant

Heavy metals (HMs) are natural components of the Earth's crust that might originate from natural and anthropogenic sources. In excess quantities, the presence of these metals is harmful for both environment and human health. Taking this into account, various investigators examined bioaccumulator species in order to reduce environmental toxicity, among these Baccharis trimera. Therefore, the present study aimed to determine the capacity of B. trimera to bioaccumulate HMs and assess consequent cytogenotoxicity following exposure. B. trimera vegetative parts were collected from two groups (1) control, in which plants were cultivated in soil exposed to distilled water, and (2) exposed, in which plants were cultivated in soil exposed to HMs including manganese (Mn), iron (Fe), lead (Pb), copper (Cu), cobalt (Co), zinc (Zn), and chromium (Cr). HMs were quantified in cultivation soil and extracts (aqueous and ethanolic) as well as infusion of B. trimera vegetative parts. Root lengths and cytogenotoxic effects were determined using Allium cepa test. Results demonstrated that all HMs studied were absorbed and bioaccumulated by B. trimera. Root lengths were decreased when exposed to ethanolic extract of B. trimera cultivated in soil exposed to HMs solution, which was the extract that exhibited the highest cytogenotoxicity values. Thus, data demonstrated that B. trimera might serve as a bioaccumulator for the reduction of environmental toxicity associated with the presence of certain HMs.

Method validation for (ultra)-trace element concentrations in urine for small sample volumes in large epidemiological studies: application to the population-based epidemiological multi-ethnic study of atherosclerosis (MESA)

Analysis of essential and non-essential trace elements in urine has emerged as a valuable tool for assessing occupational and environmental exposures, diagnosing nutritional status and guiding public health and health care intervention. Our study focused on the analysis of trace elements in urine samples from the Multi-Ethnic Study of Atherosclerosis (MESA), a precious resource for health research with limited sample volumes. Here we provide a comprehensive and sensitive method for the analysis of 18 elements using only 100 μL of urine. Method sensitivity, accuracy, and precision were assessed. The analysis by inductively coupled plasma mass spectrometry (ICP-MS) included the measurement of antimony (Sb), arsenic (As), barium (Ba), cadmium (Cd), cesium (Cs), cobalt (Co), copper (Cu), gadolinium (Gd), lead (Pb), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), strontium (Sr), thallium (Tl), tungsten (W), uranium (U), and zinc (Zn). Further, we reported urinary trace element concentrations by covariates including gender, ethnicity/race, smoking and location. The results showed good accuracy and sensitivity of the ICP-MS method with the limit of detections rangings between 0.001 μg L-1 for U to 6.2 μg L-1 for Zn. Intra-day precision for MESA urine analysis varied between 1.4% for Mo and 26% for Mn (average 6.4% for all elements). The average inter-day precision for most elements was <8.5% except for Gd (20%), U (16%) and Mn (19%) due to very low urinary concentrations. Urinary mean concentrations of non-essential elements followed the order of Sr > As > Cs > Ni > Ba > Pb > Cd > Gd > Tl > W > U. The order of urinary mean concentrations for essential trace elements was Zn > Se > Mo > Cu > Co > Mn. Non-adjusted mean concentration of non-essential trace elements in urine from MESA participants follow the order Sr > As > Cs > Ni > Ba > Pb > Cd > Gd > Tl > W > U. The unadjusted urinary mean concentrations of essential trace elements decrease from Zn > Se > Mo > Cu > Co > Mn.

Investigation of the relationship between heavy metals in the blood and depression in people with different body mass indices using the NHANES database: A cross-sectional study

BACKGROUND

Exposure to heavy metals considered a major risk factor for mental health.

OBJECTIVE

Examining how heavy metals in blood are associated with depression in individuals of various body mass indexes.

METHODS

A total sample of 15,560 individuals was screened, with 4355 participants finally enrolled to study. The PHQ-9 was used to assess participants' depressive symptoms.

RESULTS

A logistic regression analysis was used to investigate the relationship between the levels of heavy metals in the blood and the depression. Serum cadmium levels were found to be associated with risk of depression, with an odds ratio of 2.247 (95 % CI: 1.584-3.244). However, no significant correlations were observed between depression and blood levels of lead, selenium, and manganese. Subgroup analysis was performed and found that higher Cd concentrations were associated with a greater risk of depression at the same BMI. With the same Cd concentration, the risk of depression was lowest when participants' BMI was ≥30 kg/m2 and increased with increasing BMI when participants' BMI was <30 kg/m2.

LIMITATIONS

It is not possible to analyze the effect of external exposure to Cd.

CONCLUSION

Cd in blood may be positively correlated with depression in American adults, and the effect of this trend is different in people with different body mass indices. With the increase in BMI, the risk gradually rises. However, it is lowest among obese people.

Association between exposure to mixture of heavy metals and hyperlipidemia risk among U.S. adults: A cross-sectional study

Previous studies have suggested that exposure to heavy metals might increase the risk of hyperlipidemia. However, limited research has investigated the association between exposure to mixture of heavy metals and hyperlipidemia risk. To explore the independent and combined effects of heavy metal exposure on hyperlipidemia risk, this study involved 3293 participants from the National Health and Nutrition Examination Survey (NHANES), including 2327 with hyperlipidemia and the remaining without. In the individual metal analysis, the logistic regression model confirmed the positive effects of barium (Ba), cadmium (Cd), mercury (Hg), Lead (Pb), and uranium (U) on hyperlipidemia risk, Ba, Cd, Hg and Pb were further validated in restricted cubic splines (RCS) regression model and identified as positive linear relationships. In the metal mixture analysis, weighted quantile sum (WQS) regression, Bayesian kernel machine regression (BKMR), and quantile-based g computation (qgcomp) models consistently revealed a positive correlation between exposure to metal mixture and hyperlipidemia risk, with Ba, Cd, Hg, Pb, and U having significant positive driving roles in the overall effects. These associations were more prominent in young/middle-aged individuals. Moreover, the BKMR model uncovered some interactions between specific heavy metals. In conclusion, this study offers new evidence supporting the link between combined exposure to multiple heavy metals and hyperlipidemia risk, but considering the limitations of this study, further prospective research is required.

Single- and combined-phthalate exposures are associated with biological ageing among adults

BACKGROUND

Previous research has emphasized the effects of lifestyle and genetics on ageing. However, the association between exposure to phthalates, which are extensively used in cosmetics and personal care products, and ageing is still unclear.

METHOD

Data for 4711 subjects from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2010 were incorporated in the present study. The acceleration of the Klemera-Doubal method-biological age (KDM-BA) and phenotypic Age (PhenoAge) were measured by the composite of 13 biomarkers. Multiple-linear and weighted-quantile sum (WQS) regression models were constructed to explore the relationships of single- and combined-phthalate exposures, as indicated by urinary phthalate metabolites, with KDM-BA and PhenoAge. A generalized additive model (GAM) was fitted to explore the potential nonlinear relationships among the above variables.

RESULTS

Except for mono-(carboxynonyl), all urinary phthalate metabolites were associated with biological ageing, with correlation coefficients ranging from 0.241 to 0.526; however, mono-ethyl presented a negative correlation. The WQS models revealed mixed effects of combined urinary phthalate metabolites on ageing, with a 0.22-year ((95 % CI) 0.09, 0.32) increase in KDM-BA acceleration and a 0.27-year ((95 % CI) 0.13, 0.37) increase in PhenoAge acceleration for each decile increase in urinary phthalate metabolites. Moreover, MCPP, MEOHP, and MBzP seemed to be the top three phthalates in terms of biological ageing, with weights of 33.3 % and 32.2 %, 29.2 % and 17.2 %, and 21.5 % and 30.1 % in KDM-BA and PhenoAge acceleration, respectively.

CONCLUSION

Single-phthalate exposure was mostly associated with the ageing process, and combined-phthalate exposure presented mixed effects on biological ageing, emphasizing phthalate exposure as a significant risk factor for ageing.

Association between environmental cadmium exposure and increased mortality in the U.S. National Health and Nutrition Examination Survey (1999-2018)

BACKGROUND

Cadmium (Cd) is toxic to human health and increases overall mortality. In this study, we investigated the association between Cd exposure and all-cause, cardiovascular (CVD), and cancer mortality in the general population and the mediating effect of smoking on these association.

METHODS

We used data from U.S. National Health and Nutrition Examination Survey for 1999-2018. To evaluate the hazard ratio (HR) for mortality, a multiple Cox regression analysis was conducted by adjusting for age, sex, race/ethnicity, body mass index, smoking, alcohol, hypertension, diabetes, hyperlipidemia, and history of CVD and cancer. A causal mediation analysis was performed to estimate the effects of smoking.

RESULTS

Among the 31,637 subjects, 5452 (12.3%) died. Blood Cd concentrations were significantly associated with all-cause (HR 1.473, 95% confidence interval [CI] 1.403-1.546, p < 0.001), CVD (HR 1.445, 95% CI 1.344-1.554, p < 0.001), and cancer (HR 1.496, 95% CI 1.406-1.592, p < 0.001) mortality. Urinary Cd concentrations were also significantly associated with them. Using feature selection via machine learning, the importance of Cd in all-cause and cancer mortality was second only to age. The association between Cd concentrations and all-cause mortality was significant in both ever-smokers and never-smokers. The mediating effect of smoking was estimated at 32%, whereas a large proportion (68%) remained a direct effect of Cd. In a subgroup analysis of subjects with cancer history, blood Cd concentrations were significantly associated with cancer-related deaths in those with a history of breast, gastrointestinal, and skin cancers.

CONCLUSION

High Cd exposure is an important risk factor for all-cause, CVD, and cancer mortality among the general population. Cd exposure increased the risk of death even in never-smokers, and its effects unrelated to smoking were substantial, suggesting the importance of regulating other sources of Cd exposure such as food and water.

IMPACT STATEMENT

Using national large-scale data, we found that low-level environmental exposure to cadmium significantly increased the risk of all-cause, cardiovascular, and cancer mortality in the general population even after adjusting for several risk factors. Although smoking is a major source of cadmium exposure, cadmium was nevertheless significantly associated with all-cause mortality in never-smokers, and the mediating effect of smoking on this association was only 32%. Hence, other sources of cadmium exposure such as food and water may be important.

Identification of lead-binding proteins as carriers and potential molecular targets associated with systolic blood pressure

Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension.

Relationship of individual and mixed urinary metals exposure with liver function in the China National Human Biomonitoring (CNHBM) of Zhejiang Province

BACKGROUND

Heavy metals have been reported to affect liver function. However, there is currently little and inconsistent knowledge about the effects of combined and individual urinary metals on specific parameters of liver function in the general population. Therefore, this study aimed to investigate their associations.

METHODS

This study involved 807 general population from the China National Human Biomonitoring of Zhejiang Province 2017-2018. Concentrations of urinary metals, including Chromium (Cr), Cobalt (Co), Nickle (Ni), Arsenic (As), Selenium (Se), Molybdenum (Mo), Cadmium (Cd), Thallium (Tl) and Lead (Pb) were measured. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein (TP), albumin (ALB), direct bilirubin (DBIL), total bilirubin (TBIL) as liver function biomarkers. Multivariable linear regression and weighted quantile sum (WQS) regression were employed to explore the associations of urinary metals with liver function biomarkers. Subgroup analysis stratified by gender and age, excluding smokers and drinkers for sensitivity analysis.

RESULTS

Both statistical models indicated that urinary metals were positively associated with ALT and AST, while negatively with TP, ALB, DBIL and TBIL. In the WQS analysis, each quartile increase in the ln-transformed levels of metal mixtures was associated with 4.11 IU/L (95% CI: 1.07, 7.15) higher ALT and 3.00 IU/L (95% CI: 1.75, 4.25) higher AST, as well as, with 0.67 g/L (95% CI: 1.24, -0.11) lower TP, 0.74 g/L (95% CI: 1.09, -0.39) lower ALB, 0.38 μmol/L (95% CI: 0.67, -0.09) lower DBIL, and 1.56 μmol/L (95% CI: 2.22, -0.90) lower TBIL. The association between urinary metals and ALT was primarily driven by Cd (55.8%), Cr contributed the most to the association with AST (20.2%) and TBIL (45.2%), while the association with TP was primarily driven by Ni (38.2%), the association with ALB was primarily driven by As (32.8%), and the association with DBIL was primarily driven by Pb (30.9%). The associations between urinary metals and liver function might differ by sex and age.

CONCLUSION

Urinary metals were significantly associated with liver function parameters. Further studies are required to clarify the relationship between heavy metals and liver function.

Mediation analysis of urinary metals and stroke risk by inflammatory markers

BACKGROUND

The association between metals and stroke has been reported, but the mediating role of inflammation between metals and stroke remains unclear.

METHODS

We included 9326 adults from the National Health and Nutrition Examination Survey in this study. Through least absolute selection and shrinkage operator (LASSO) regression, weighted quantile sum (WQS) regression, logistic regression, linear regression, restricted cubic spline analysis, and mediation analysis, we explored the association between metals and stroke, as well as the association between metals and inflammatory indicators, and further evaluated the mediating effect of inflammatory indicators on the association between selected metals and stroke risk.

RESULTS

The results of the present study suggested positive associations between mixed metals, cadmium and uranium and stroke risk. There is a positive correlation and dose‒response relationship between cadmium and C-reactive protein (CRP). Moreover, CRP mediates 10.1% of the association between cadmium and stroke.

CONCLUSIONS

At the epidemiological level, CRP mediates the association between cadmium and stroke risk, suggesting that inflammation may be a potential mechanism for metal-induced stroke.

Adequate Intake of Dietary Fiber May Relieve the Detrimental Impact of Blood Lead on Dyslipidemia among US Adults: A Study of Data from the National Health and Nutrition Examination Survey Database

Lead (Pb) exposure is a well-established risk factor for dyslipidemia, and people are exposed to it in multiple ways daily. Dietary fiber is presumed to improve lipid metabolism disorders, but it is still unknown whether it can relieve the detrimental impact of Pb on dyslipidemia. We used publicly accessible data from the 2011-2016 cycles of the National Health and Nutrition Examination Survey (NHANES). A total of 2128 US adults were enrolled for the subsequent analysis. Heavy metal concentrations in blood were measured using inductively coupled plasma mass spectrometry (ICP-MS). A weighted logistic regression was conducted to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The dose-response relationship between blood heavy metals and dyslipidemia was explored using a weighted restricted cubic spline (RCS) analysis. After fully adjusting for potential confounding factors (age, gender, race, education level, ratio of family income to poverty, marital status, body mass index, physical activity, waist circumference, smoke, alcohol drinking and history of metabolic syndrome, hypertension, and diabetes), a positive association between blood Pb levels and dyslipidemia risk was revealed (OR = 1.20, 95% CI: 1.03-1.40). Dietary fiber intake may significantly modify the association between blood Pb levels and dyslipidemia (p-interaction = 0.049), with a stronger association (OR = 1.26, 95% CI: 1.05-1.52) being revealed in individuals with an inadequate intake of dietary fiber (<14 g/1000 kcal/day), but a null association (OR = 1.01, 95% CI: 0.72-1.42) being observed in those with an adequate intake of dietary fiber (≥14 g/1000 kcal/day). Moreover, the weighted RCS analysis showed that compared with the average blood Pb exposure level (4.24 µg/dL), a lower blood Pb exposure level (3.08 µg/dL) may contribute to the risk of dyslipidemia in the group with an inadequate dietary fiber intake. Our findings suggest that Pb exposure in blood may be a risk factor for dyslipidemia. However, an adequate dietary fiber intake may offset the risk of dyslipidemia caused by blood Pb exposure. Since avoiding Pb exposure in daily life is difficult, increasing dietary fiber intake in the future might be a promising approach to alleviate dyslipidemia caused by Pb exposure.

Cadmium exposure is associated with decreased muscle strength in middle-aged and older adults

Cadmium, a toxic heavy metal, is ubiquitous in the environment. No previous research has evaluated the relationship of blood and urine cadmium levels with muscle strength measured by isokinetic knee extensor strength. This analysis included participants who were aged 50 years or older and had measurements of cadmium in blood (n = 2052) and urine (n = 811) from the National Health and Nutrition Examination Survey. Blood and urine cadmium levels were assessed by atomic absorption spectrometry and inductively coupled plasma-mass spectrometry, respectively. Isokinetic dynamometry was used to assess knee extensor strength (peak force). Linear regression models were used to examine the association between cadmium exposure and peak force, with adjustment for potential confounders. The median values (25-75th percentiles) of blood cadmium and creatinine-corrected urine cadmium were 0.50 μg/L (0.40-0.70) and 0.43 μg/g (0.27-0.71), respectively. After adjusting for potential confounders, linear dose-response relationships of peak force with blood and urine cadmium concentrations were observed in the present study. Compared to participants in the highest quartile of blood cadmium and urine cadmium, the peak force decreased by 6.99 Newton (95% CI: -21.96, 7.98) and 26.84 Newton (95% CI: -44.34, -9.34) in participants in the lowest quartiles, respectively. The observed associations were more evident among men participants. Our findings suggest that the cadmium levels have a dose response relationship with decreased muscle strength measured by isokinetic knee extensor strength in middle aged and older adults. Further longitudinal investigations are required to disentangle these complexities on this issue.

Associations between cadmium exposure and whole-body aging: mediation analysis in the NHANES

INTRODUCTION

Even though cadmium (Cd) exposure and cellular senescence (telomere length) have been linked in previous studies, composite molecular aging biomarkers are more significant and reliable factors to consider when examining the connection between metal exposure and health outcomes. The purpose of this research was to assess the association between urinary cadmium (U-Cd) and whole-body aging (phenotypic age).

METHODS

Phenotypic age was calculated from chronological age and 9 molecular biomarkers. Multivariate linear regression models, subgroup analysis, and smoothing curve fitting were used to explore the linear and nonlinear relationship between U-Cd and phenotypic age. Mediation analysis was performed to explore the mediating effect of U-Cd on the association between smoking and phenotypic age.

RESULTS

This study included 10,083 participants with a mean chronological age and a mean phenotypic age of 42.24 years and 42.34 years, respectively. In the fully adjusted model, there was a positive relationship between U-Cd and phenotypic age [2.13 years per 1 ng/g U-Cd, (1.67, 2.58)]. This association differed by sex, age, and smoking subgroups (P for interaction < 0.05). U-Cd mediated a positive association between serum cotinine and phenotypic age, mediating a proportion of 23.2%.

CONCLUSIONS

Our results suggest that high levels of Cd exposure are associated with whole-body aging.

The ratio of monocyte count and high-density lipoprotein cholesterol mediates the association between urinary tungsten and cardiovascular disease: a study from NHANES 2005-2018

Tungsten (W) is an emerging contaminant that can damage multiple systems in humans. However, studies of its effects on cardiovascular disease (CVD) are limited. The monocyte count to high-density lipoprotein cholesterol ratio (MHR) is a composite inflammatory index of great concern in recent years, derived from lipid and cell inflammation parameters, that is used to indicate the risk of CVD. This study aimed to investigate the association between urinary W and CVD in the general population and compare the mediating effects of lipids, cell inflammatory parameters, and MHR to find a better target for intervention. We analyzed data from 9137 (≥ 20 years) participants in the National Health and Nutrition Examination Survey (NHANES), from 2005 to 2018. Restricted cubic splines (RCS) and survey-weighted generalized linear models (SWGLMs) were used to assess the relationship between W and CVD. Mediated analyses were used to explore lipids, cell inflammatory parameters, and MHR in the possible mediating pathways between W and CVD. In SWGLM, we found that W enhances the risk of CVD, especially congestive heart failure (CHF), coronary heart disease (CHD), and angina pectoris (AP). Women, higher age groups (≥ 55 years), and those with hypertension were vulnerable to W in the subgroup analysis. Mediation analysis showed that monocyte count (MC), white blood cell count (WBC), high-density lipoprotein cholesterol (HDL), and MHR played a mediating role between W and CVD in proportions of 8.49%, 3.70%, 5.18%, and 12.95%, respectively. In conclusion, our study shows that urinary W can increase the risk of CVD, especially for CHF, CHD, and AP. Women, older age groups, and people with hypertension seem to be more vulnerable to W. In addition, MC, WBC, HDL, and MHR mediated the association between W and CVD, especially MHR, which suggests that we should consider it as a priority intervention target in the future.

Mitigation role of physical exercise participation in the relationship between blood cadmium and sleep disturbance: a cross-sectional study

The neurotoxicity of heavy metals received increasingly attention in recent years. Sleeping is regulated and coordinated by nervous system, however, the health hazard of heavy metal like cadmium (Cd) exposure on sleep health remained unknown. Rescue strategies like physical exercise (PE) has emerged to mitigate such influence. An epidemiological design with cross-sectional data from National Health and Nutrition Examination Survey 2007-2010 was applied. The relationship between three blood heavy metals [cadmium (Cd), lead (Pb), mercury (Hg)] and sleep disturbance was analyzed. A total of 8,751 participants were finally included in and the weighted participants were 330,239,463. Weighted quantile sum (WQS) regression indicated that mixed blood metals were positively related to risk of sleep disturbance and the mixture effect of exposure to heavy metals was mainly attributable to Cd (89.1%). Weighted logistic regression showed a significant positive association between the highest quartile of blood Cd and sleep disturbance [(OR (95% CI)): 1.191 (1.014,1.400), p = 0.036] in the fully adjusted model, while no association was found under Pb and Hg exposure. In the association between Q3 and Q4 level of blood Cd and sleep disturbance, moderate-to-vigorous physical exercise group had lower risks than none and low exercise group. In the restricted cubic spline model, it was also verified that higher PE participation was associated with the lowest incidence of sleep disturbance with the increment in Cd concentration. Our study suggested that both policy makers and the public should minimize heavy metal exposure. Moreover, conducting moderate to vigorous physical exercise is a protecting factor to mitigate Cd's influence on sleep health.

Sex-specific associations between nine metal mixtures in urine and urine flow rate in US adults: NHANES 2009-2018

Background

The urinary system serves as a crucial pathway for eliminating metallic substances from the body, making it susceptible to the effects of metal exposure. However, limited research has explored the association between metal mixtures and bladder function. This study aims to investigate the relationship between urinary metal mixtures (specifically barium, cadmium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten) and urine flow rate (UFR) in the general population, utilizing multiple mixture analysis models.

Methods

This study utilizes data obtained from the National Health and Nutrition Examination Survey. After adjusting for relevant covariates, we assessed the correlations between metal mixtures and UFR using three distinct analysis models: weighted quantile sum (WQS), quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR). Additionally, a gender-stratified analysis was conducted. Finally, we also performed sensitivity analyses.

Results

A total of 7,733 subjects were included in this study, with 49% being male. The WQS regression model, when fitted in the positive direction, did not yield any significant correlations in the overall population or in the male and female subgroups. However, when analyzed in the negative direction, the WQS index exhibited a negative correlation with UFR in the overall group (β = -0.078; 95% CI: -0.111, -0.045). Additionally, a significant negative correlation between the WQS index and UFR was observed in the female group (β = -0.108; 95% CI: -0.158, -0.059), while no significant correlation was found in the male group. The results obtained from the qgcomp regression model were consistent with those of the WQS regression model. Similarly, the BKMR regression model revealed a significant negative correlation trend between metal mixtures and UFR, with cadmium and antimony potentially playing key roles.

Conclusion

Our study revealed a significant negative correlation between urinary metal mixture exposure and mean UFR in US adults, with notable gender differences. Specifically, higher urinary levels of cadmium and antimony were identified as potential key factors contributing to the decrease in mean UFR. These findings significantly contribute to the existing knowledge on the impact of metal mixtures on bladder function and provide valuable insights for safeguarding bladder health and preventing impaired bladder function.

Association of blood cadmium with all-cause and cause-specific mortality in patients with hypertension

Background

Cadmium is a commonly found heavy metal with a prolonged biological half-life, which results in long-term health burden for the population. Prior studies have demonstrated an association between blood cadmium and hypertension. However, few studies examined the relationship between blood cadmium and long-term health outcomes in patients with hypertension. This study aimed to investigate the association of blood cadmium with mortality in patients with hypertension.

Methods

This study analyzed data from the National Health and Nutrition Examination Survey 1999-2012. Complex sampling-weighted multivariate Cox proportional hazards models were used to evaluate the hazard ratios (HRs) of all-cause, cardiovascular, and Alzheimer's disease mortality in patients with hypertension classified by blood cadmium concentrations' quantiles.

Results

The study included 12,208 patients with hypertension with a median follow-up duration of 10.8 years. During this period, there were 4,485 all-cause deaths, including 1,520 cardiovascular deaths and 180 Alzheimer's disease deaths. Compared with the lowest quintile of blood cadmium (≤0.25 μg/L) group, the highest quintile of blood cadmium (≥0.80 μg/L) group's adjusted HRs were 1.85 (95% CI, 1.59-2.14) for all-cause mortality, 1.76 (95% CI, 1.33-2.34) for cardiovascular mortality, and 3.41 (95% CI, 1.54-7.51) for Alzheimer's disease mortality. Additionally, the adjusted HR for cardiovascular mortality was 2.12 (95% CI, 1.36-3.30) in never-smoking patients with hypertension.

Conclusion

Higher blood cadmium is associated with increased risks of all-cause, cardiovascular, and Alzheimer's disease mortality in patients with hypertension. The effect of blood cadmium on cardiovascular mortality may be more pronounced in never-smoking hypertensive patients.

Exposure to phenols, chlorophenol pesticides, phthalate and PAHs and mortality risk: A prospective study based on 6 rounds of NHANES

OBJECTIVES

Human exposure to various endocrine disrupting chemicals (EDCs) is widespread and long-lasting. The primary objective of this study was to prospectively evaluate the association of combined exposure of phenols, chlorophenol pesticides, phthalate and polycyclic aromatic hydrocarbons (PAHs) and mortality risk in a representative US population.

METHODS

The data on urinary levels of phenols, chlorophenol pesticides, phthalates, and PAH metabolites, were collected from participants aged ≥20 years in six rounds of the National Health and Nutrition Examination Survey (NHANES) (2003-2014). NHANES-linked death records up to December 31, 2015 were used to ascertain mortality status and cause of death. Cox proportional hazards and competing risk models were mainly used for chemical and mortality risk association analysis. The weighted quantile sum (WQS) regression and the least absolute shrinkage and selection operator regression were employed to estimate the association between EDC co-exposure and mortality risk.

RESULTS

High levels of mono-n-butyl phthalate, monobenzyl phthalate, and 1-napthol were significantly associated with increased risk of all cause, cardiovascular disease (CVD) and cancer mortality among all participants. WQS index was associated with the risks of all-cause (hazard ratio [HR] = 1.389, 95%CI: 1.155-1.669) and CVD mortality (HR = 1.925, 95%CI: 1.152-3.216). High co-exposure scores were associated with elevated all-cause (HR = 2.842, 95% CI: 1.2.094-3.858), CVD (HR = 1.855, 95% CI: 1.525-2.255), and cancer mortality risks (HR = 2.961, 95% CI: 1.468-5.972). The results of subgroup analysis, competing risk model, and sensitivity analysis were generally consistent with the findings from the main analyses, indicating the robustness of our findings.

CONCLUSIONS

This study provided the first epidemiological evidence that co-exposure to EDC at fairly low levels contributed to elevated mortality risk among US adults. The underlying mechanisms for the effects of EDC co-exposure on human health are worthy of future exploration.

Serum copper levels and risk of major adverse cardiovascular events: a systematic review and meta-analysis

Background

Despite the fact that several studies have investigated the association between serum copper levels (S-Cu) and the risk of cardiovascular diseases, this relationship remains unclear. The aims of this study were to investigate the association between S-Cu and risk of major adverse cardiovascular events (MACE), including total stroke, ischemic stroke, hemorrhagic stroke, myocardial infarction and cardiovascular mortality, and identify potential sources of results heterogeneity.

Methods

We carried out a systematic review and meta-analysis. The selection criteria were: (1) Observational studies (cohort studies, case-control studies and hybrid studies); (2) Studies containing quantitative data about the relationship between S-Cu and risk of MACE; (3) Estimating association measures; and (4) Studies written in English, French or Spanish. Overall pooled Odds ratio (pOR) and 95% confidence intervals (95% CI) of MACE for the highest vs. lowest S-Cu category were calculated using random-effects models.

Results

Sixteen studies with a total of 41,322 participants were included in the meta-analysis: 10 prospective cohort studies, 5 nested case-control studies and 1 case-control study. Comparing highest vs. lowest category, high S-Cu levels were associated with total stroke (pOR: 1.49, 95% CI 1.22-1.82; I² = 0%, p = 0.54), myocardial infarction (pOR: 1.31, 95% CI 1.17-1.46; I² = 0.0%, p = 0.92) and cardiovascular mortality (pOR: 1.60, 95% CI 1.39-1.86; I² = 0.0%, p = 0.54). Subgroup analysis showed that studies with a hybrid design had higher risks for cardiovascular mortality (pOR: 3.42, 95% CI 1.98-5.92) and ischemic stroke (pOR: 1.54, 95% CI 1.30-1.83).

Conclusion

High S-Cu levels were associated with an increased risk of total stroke, myocardial infarction and cardiovascular mortality. Hybrid studies seems to modify the strength of the association between S-Cu and the risk of cardiovascular mortality and ischemic stroke.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022370782], identifier [CRD42022370782].

Association of blood metals with serum sex hormones in adults: A cross-sectional study

Heavy metals such as lead, mercury, and cadmium have been identified to have negative impacts on human health. Although the individual effects of these metals have been extensively researched, the present study aims to explore their combined effects and their association with serum sex hormones among adults. Data for this study were obtained from the general adult population of the 2013-2016 National Health and Nutrition Survey (NHANES) and included five metal (mercury, cadmium, manganese, lead, and selenium) exposures and three sex hormones (total testosterone [TT], estradiol [E2], and sex hormone-binding globulin [SHBG]) levels. The free androgen index (FAI) and TT/E2 ratio were also calculated. The relationships between blood metals and serum sex hormones were analysed using linear regression and restricted cubic spline regression. The effect of blood metal mixtures on sex hormone levels was examined using the quantile g-computation (qgcomp) model. There were 3,499 participants in this study, including 1,940 males and 1,559 females. In males, positive relationships between blood cadmium and serum SHBG (β=0.049 [0.006, 0.093]), lead and SHBG (β=0.040 [0.002, 0.079]), manganese and FAI (β=0.080 [0.016, 0.144]), and selenium and FAI (β=0.278 [0.054, 0.502]) were observed. In contrast, manganese and SHBG (β=-0.137 [-0.237, -0.037]), selenium and SHBG (β=-0.281 [-0.533, -0.028]), and manganese and TT/E2 ratio (β=-0.094 [-0.158, -0.029]) were negative associations. In females, blood cadmium and serum TT (β=0.082 [0.023, 0.141]), manganese and E2 (β=0.282 [0.072, 0.493]), cadmium and SHBG (β=0.146 [0.089, 0.203]), lead and SHBG (β=0.163 [0.095, 0.231]), and lead and TT/E2 ratio (β=0.174 [0.056, 0.292]) were positive relationships, while lead and E2 (β=-0.168 [-0.315, -0.021]) and FAI (β=-0.157 [-0.228, -0.086]) were negative associations. This correlation was stronger among elderly women (>50 years old). The qgcomp analysis revealed that the positive effect of mixed metals on SHBG was mainly driven by cadmium, while the negative effect of mixed metals on FAI was mainly driven by lead. Our findings indicate that exposure to heavy metals may disrupt hormonal homeostasis in adults, particularly in older women.

Physical activity mitigates the influence of blood cadmium on memory function: a cross-sectional analysis in US elderly population

Current evidence showed that heavy metal exposure including cadmium (Cd) exposure might contribute to memory function impairment in youth, while this association has not been extensively explored in senior groups. Complementary therapy like physical activity (PA) is proved to enhance memory; however, the combined effects of Cd exposure and PA are interesting issues worth investigating. Cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 were analyzed. Multivariable weighted linear regression model and restricted cubic splines analysis were used to examine the association between blood Cd, PA, and memory function. Ultimately, 1884 samples were analyzed, and the weighted participants were 98,350,183. Results showed that in the immediate and delayed recall tests, a negative association was found between blood Cd and scores for the fully adjusted model, while a positive association was detected with PA on memory test scores. In subgroup analysis, for the delayed recall test, in lower Cd exposure (Cd = Q1), stronger effect size was found in the moderate level PA group than the higher level PA group (moderate level PA group, β = 1.133, 95% CI: 0.330, 1.936; high level PA group, β = 0.203, 95% CI: - 0.314, 0.719), and this finding also existed in higher (Cd = Q4) exposure (moderate level PA group, β = 0.988, 95% CI: 0.267, 1.708; high level PA group, β = 0.830, 95% CI: 0.261, 1.400). Moreover, the non-linear relationship between Cd exposure and performance of CERAD test under different levels of PA was reported, and the moderate level PA group performed best from lower to higher blood Cd. According to our research, the benefit of PA did not always expand with the PA intensity increment under different Cd exposure. Performing an appropriate level of physical exercise could alleviate the memory decline under Cd exposure in the elder groups. Further biological investigations are warranted to verify these findings.

Associations of urinary and blood cadmium concentrations with all-cause mortality in US adults with chronic kidney disease: a prospective cohort study

Epidemiological evidence for the relationship between cadmium exposure and mortality in specific chronic kidney disease (CKD) populations remains scarce. We aimed to explore the relationships between cadmium concentrations in urine and blood and all-cause mortality among CKD patients in the USA. This cohort study was composed of 1825 CKD participants from the National Health and Nutrition Examination Survey (NHANES) (1999-2014) who were followed up to December 31, 2015. All-cause mortality was ascertained by matching the National Death Index (NDI) records. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality in relation to urinary and blood cadmium concentrations by Cox regression models. During an average follow-up period of 82 months, 576 CKD participants died. Compared with the lowest quartiles, HRs (95% CIs) for all-cause mortality associated with the fourth weighted quartiles of urinary and blood cadmium concentrations were 1.75 (1.28 to 2.39) and 1.59 (1.17 to 2.15), respectively. Furthermore, the HRs (95% CIs) for all-cause mortality per ln-transformed IQR increment in cadmium concentrations in urine (1.15 μg/g U_Cr) and blood (0.95 μg/L) were 1.40 (1.21 to 1.63) and 1.22 (1.07 to 1.40), respectively. Linear concentration-response relationships between urinary and blood cadmium concentrations and all-cause mortality were also found. Our findings suggested that increased cadmium concentrations in both urine and blood significantly contributed to enhanced mortality risk in CKD patients, thus highlighting that efforts to reduce cadmium exposure may reduce mortality risk in high-risk populations with CKD.

Investigation of imbalances in essential/toxic metal levels in the blood of laryngeal cancer patients in comparison with controls

Laryngeal carcinoma is one of the common types of head and neck cancer, with men being more likely than women to develop it. Diet, age, gender, smoking habits, and environmental factors play important roles in its development. The goal of this study was to ascertain if there were imbalances in essential and toxic trace metals owing to the initiation and progression of laryngeal cancer. Atomic absorption spectrometry was employed to quantify selected macroelements, and essential/toxic trace metals in blood of the cancerous patients and matching controls. Significantly higher concentrations of Pb, Cu, Fe, and Sr while substantially lower levels of Na, K, Ca, and Mg were observed in the cancer patients compared with the controls. Considerably disparate mutual relationships among the macroelements, and essential/toxic trace metals in the patients and controls were manifested by their correlation coefficients. Similarly, multivariate apportionment of the metal levels showed appreciably diverse associations and grouping in the patients and controls. The laryngeal cancer patients exhibited significant disparities in the metal levels among various sub-types (supraglottic, subglottic, transglottic, and glottic cancer) and stages (I, II, III, and IV) of the disease. Most of the metals revealed distinct differences based on the gender, habitat, age, eating preferences, and smoking habits in both donor groups. Overall, the study demonstrated significant imbalances among the macroelements, and essential/toxic trace metal levels in the blood of laryngeal cancer patients compared to the controls.

Associations with Blood Lead and Urinary Cadmium Concentrations in Relation to Mortality in the US Population: A Causal Survival Analysis with G-Computation

Using the parametric g-formula, we estimated the 27-year risk of all-cause and specific causes of mortality under different potential interventions for blood lead (BLLs) and urinary cadmium (UCd) levels. We used data on 14,311 adults aged ≥20 years enrolled in the NHANES-III between 1988 and 1994 and followed up through 31 Dec 31 2015. Time and cause of death were determined from the National Death Index records. We used the parametric g-formula with pooled logistic regression models to estimate the relative and absolute risk of all-cause, cardiovascular, and cancer mortality under different potential threshold interventions for BLLs and UCd concentrations. Median follow-up was 22.5 years. A total of 5167 (36%) participants died by the end of the study, including 1550 from cardiovascular diseases and 1135 from cancer. Increases in BLLs and creatinine-corrected UCd levels from the 5th to the 95th percentiles were associated with risk differences of 4.17% (1.54 to 8.77) and 6.22% (4.51 to 12.00) for all-cause mortality, 1.52% (0.09 to 3.74) and 1.06% (-0.57 to 3.50) for cardiovascular disease mortality, and 1.32% (-0.09 to 3.67) and 0.64% (-0.98 to 2.80) for cancer mortality, respectively. Interventions to reduce historical exposures to lead and cadmium may have prevented premature deaths, especially from cardiovascular disease.

Development of an interpretable machine learning model associated with heavy metals' exposure to identify coronary heart disease among US adults via SHAP: Findings of the US NHANES from 2003 to 2018

Limited information is available on the links between heavy metals' exposure and coronary heart disease (CHD). We aim to establish an efficient and explainable machine learning (ML) model that associates heavy metals' exposure with CHD identification. Our datasets for investigating the associations between heavy metals and CHD were sourced from the US National Health and Nutrition Examination Survey (US NHANES, 2003-2018). Five ML models were established to identify CHD by heavy metals' exposure. Further, 11 discrimination characteristics were used to test the strength of the models. The optimally performing model was selected for identification. Finally, the SHapley Additive exPlanations (SHAP) tool was used for interpreting the features to visualize the selected model's decision-making capacity. In total, 12,554 participants were eligible for this study. The best performing random forest classifier (RF) based on 13 heavy metals to identify CHD was chosen (AUC: 0.827; 95%CI: 0.777-0.877; accuracy: 95.9%). SHAP values indicated that cesium (1.62), thallium (1.17), antimony (1.63), dimethylarsonic acid (0.91), barium (0.76), arsenous acid (0.79), total arsenic (0.01) in urine, and lead (3.58) and cadmium (4.66) in blood positively contributed to the model, while cobalt (-0.15), cadmium (-2.93), and uranium (-0.13) in urine negatively contributed to the model. The RF model was efficient, accurate, and robust in identifying an association between heavy metals' exposure and CHD among US NHANES 2003-2018 participants. Cesium, thallium, antimony, dimethylarsonic acid, barium, arsenous acid, and total arsenic in urine, and lead and cadmium in blood show positive relationships with CHD, while cobalt, cadmium, and uranium in urine show negative relationships with CHD.

Single and combined associations of blood lead and essential metals with serum lipid profiles in community-dwelling adults

Background

Although several studies have examined the relationships between lead (Pb) exposure and serum lipid profiles, the associations of the metal mixture, including lead (Pb) and essential metals with lipid profiles, remain unclear.

Objective

To investigate the associations of the metal mixture including Pb and essential metals [magnesium (Mg), manganese (Mn), copper (Cu), iron (Fe), zinc (Zn), and calcium (Ca)] with serum lipid profiles [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)], as well as the potential interactions among the metals.

Methods

Nine hundred and ninety-eight Chinese community-dwelling adults completed a questionnaire and underwent checkups of anthropometric parameters, serum lipid profile levels (TC, TG, LDL-C, and HDL-C), and blood metal concentrations (Pb, Mg, Mn, Cu, Fe, Zn, and Ca). The multivariable linear regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) were applied to evaluate the single and combined associations of blood Pb and essential metals with serum lipid profiles.

Results

In the multivariable linear regression model, the blood Pb was positively associated with TC, LDL-C, and HDL-C (p < 0.05, all), and the blood Mg were positively associated with serum TC, LDL-C, and Ln TG (p < 0.05, all). In the WQS regression and BKMR models, the metal mixture of blood Pb and the essential metals was positively associated with all of the serum lipid profiles. In addition, an inverse U-shaped association of Pb with Ln TG and the positive interactive effect between blood Pb and Mg levels on TC and LDL-C were found.

Conclusion

The levels of blood Pb, together with the essential metals, especially Mg levels, are suggested to be considered when assessing dyslipidemia risk. However, more evidence is still needed to validate the conclusions.

Association of Blood Heavy Metal Exposure with Atherosclerotic Cardiovascular Disease (ASCVD) Among White Adults: Evidence from NHANES 1999-2018

Cardiovascular diseases (CVD) are main public health concerns highly prevalent in industrialized societies where human health is threatened by a series of environmental pollutants, particularly heavy metal contaminants. We aimed to find out if blood heavy metals are associated with the 10-year risk of atherosclerotic cardiovascular disease (ASCVD) in a nationally representative sample of US adults. We analyzed the cross-sectional data on blood heavy metals of 3268 non-Hispanic white participants aged 40-79 years from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. We introduced a risk estimation algorithm, namely the 2013 Pooled Cohort Equations (PCE), to assess the risk for ASCVD over a 10-year period. The 10-year risk for ASCVD was categorized as either reduced risk (< 7.5% risk) or elevated risk (≥ 7.5% risk). Blood lead, cadmium, and mercury were distributed into four quartiles. We used weighted multivariate logistic regression models and restricted cubic spline (RCS) regression to detect the association of blood heavy metal exposure with 10-year ASCVD risk. Following the adjustment of covariates, the adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for elevated 10-year ASCVD risk for participants from the highest quartiles were 4.50 (2.88-7.02), 2.59 (1.68-4.00), and 1.06 (0.66-1.71) for blood cadmium, lead, and mercury compared to the lowest quartiles, respectively. The RCS plot demonstrated that blood cadmium was linearly and positively associated with 10-year ASCVD risk (P for nonlinearity = 0.112). According to our findings, non-Hispanic whites aged 40-79 years had a greater 10-year ASCVD risk as their blood lead and cadmium levels increased. Consequently, when establishing approaches for ASCVD prevention, blood heavy metals should be considered.

Sex-specific associations of the urinary fourteen-metal mixture with NAFLD and liver fibrosis among US adults: A nationally representative study

Although previous studies have examined the hepatotoxicity of single metal exposure, the associations between metal mixture and non-alcoholic fatty liver disease (NAFLD) or fibrosis remain unclear. This study investigated the associations of urinary metal mixture with the risks of NAFLD and liver fibrosis in US adults using data from the National Health and Nutrition Examination Survey (NHANES) from 2017.01 to 2020.03. Vibration-controlled transient elastography was used to detect the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM), which are indicators of NAFLD and liver fibrosis respectively. Three novel mixture modeling approaches including the Bayesian kernel machine regression (BKMR), weighted quantile sum (WQS) regression and quantile g-computation (qgcomp) were used to estimate the associations of the urinary fourteen-metal mixture with Ln CAP and Ln LSM. There were 2283 adults aged over 18 years (1209 women and 1074 men) were included. Among women, urinary metal mixture was positively associated with Ln CAP in the BKMR and qgcomp models (both P < 0.05). However, no significantly associations of urinary metal mixture with Ln CAP were observed among men in all models (all P > 0.05). The metal mixture was not associated with Ln LSM in the three models regardless of genders (all P > 0.05). In conclusion, we observed sex-specific associations between urinary metal mixture and the prevalence of NAFLD in US adults. These findings emphasize the role of environmental heavy metal exposure in the development of NAFLD, and confirm the need for more prospective cohort studies on sex-specific manner.

Accurate and sensitive determination of Sb(III) in water samples using UV-VIS spectrophotometry after simultaneous complexation and preconcentration with deep eutectic solvent/DTZ probe-based liquid-liquid microextraction

This study describes the determination of trace levels of antimony(III) by UV-Vis spectrophotometer after preconcentration by the deep eutectic solvent/dithizone probe-based liquid-liquid microextraction method. Ditizone was used as a ligand to form the coordinated antimony complex before extraction in the preconcentration process. In the microextraction method developed in the study, deep eutectic solvent was used to dissolve the complexing agent; thus, the complexation was performed at the same time as the extraction of antimony complex by deep eutectic solvent. All variables likely to affect the ligand-antimony(III) complex, extraction efficiency, and spectroscopic measurement were optimized to lower the detection limit. Under the determined optimum conditions, the detection limit for Sb was calculated as 1.6 × 10^-3 mg/L. The detection limit obtained with the method is much lower than the value obtained in the Uv-Vis spectrophotometer with the traditional method. In this study, the percent relative standard deviation for the lowest concentration was calculated as 3.12% (n = 8). This value indicates that the analysis performed has high precision. The applicability of the method was determined by performing spiked recovery tests on tap water taken from different regions. Satisfactory recovery results were obtained between 91 and 105% at three different concentrations.

Combined effects of multiple metals on hearing loss: A Bayesian kernel machine regression approach

BACKGROUND

Exposure to heavy elements is considered one of the risks of hearing loss. The combined effect of multiple metals on different hearing losses has not been extensively studied.

METHODS

This study deals with the association between different metals (Ba, Cd, Co, Cs, Mo, Pb, Mn, Sn, Sb, Tl, W) and hearing loss in the 2013-2018 National Health and Nutrition Examination Survey (NHANES). Associations were estimated by a generalized linear regression model (GLM) adjusting for age, gender, race/ethnicity, educational level, marital status, drinking status, hypertension, diabetes, smoking status, noise exposure, body mass index, and income-poverty ratio. The joint effects of mixed exposure were assessed by weighted quantile sum (WQS) model and Bayesian kernel machine regression (BKMR). The effect of multiple metals on speech-frequency hearing loss (SFHL) and high-frequency hearing loss (HFHL) was further calculated. The odds ratio (OR) indicates the risk of every metal exposure.

RESULTS

A total of 2205 adult participants were enrolled from NHANES. Cd, Pb, Sb and Sn had significant effects on total hearing loss. The WQS model found that mixed exposure to heavy elements was significantly positively associated with total hearing loss (OR: 1.136; 95% CI: 1.031, 1.253) after adjusting for various covariates. The ORs of mixed exposure in the SFHL and HFHL groups were 1.066 (95% CI: 0.994, 1.143) and 1.102 (95% CI: 1.013, 1.199), respectively. BKMR found a significant positive association between multiple metals and hearing loss. The results showed that there may be potential interactions between Cd, Pb and other metals.

CONCLUSIONS

Multiple metals have joint effects on hearing loss in the United States. The findings provide practitioners with important scientific evidence for possible interventions.

Correlative study on heavy metal-induced oxidative stress and hypertension among the rural population of Malwa Region of Punjab, India

Heavy metal-induced toxicity contributes to the progression of various metabolic disorders and possible mechanisms involved in disease progression are not well established. In this study, the correlation of  heavy metal exposure and  hypertension have been demonstrated. The results showed that in hypertensive subjects, the lipid profiles (triglycerides, LDL-C, HDL-C, and total cholesterol) and cardiac markers (CK-MB and LDH) were altered abruptly. As a consequence of heavy- induced oxidative stress, the oxidants (TBARS and protein carbonyls) and antioxidants (SOD, GSH, and TAC) were significantly increased and decreased, respectively in hypertension subjects. The concentrations of heavy metals (Pb, Cd, and As) exceeded the permissible limits in hypertensive subjects. The Nrf-2 genotyping indicated that heavy metals may induce mutations at molecular level. The results of correlation analysis revealed that the heavy metals interact with cellular components and interfere with metabolic processes which then results in disturbed lipid profile, enhanced oxidative stress, and reduced antioxidant status. The current study systematically estimated the association of hair and nail heavy metal concentrations with hypertension among the population residing in the Malwa region of Punjab. The proposed study highlighted that heavy metals act as a silent risk factor in the hypertension progression in the population of Malwa region. Future studies are required to confirm current findings and further scrutinize the effect of heavy metals exposure in early adulthood, early, and late mid-life to develop metabolic complications such as hypertension.