Association of Endocrine-Disrupting Chemicals with All-Cause and Cause-Specific Mortality in the U.S.: A Prospective Cohort Study

Association between secondhand smoke exposure and osteoporosis risk in postmenopausal women: a cross-sectional analysis of NHANES data

BACKGROUND

This study aimed to investigate the association between smoke exposure and the risk of osteoporosis in postmenopausal women in the United States, using data from the National Health and Nutrition Examination Survey (NHANES).

METHODS

A cross-sectional analysis was conducted using NHANES data from 2005 to 2010, 2013 to 2014, and 2017 to 2018. The study population consisted of postmenopausal women aged 18 years and older. Their bone health status was assessed using self-reported osteoporosis and dual-energy X-ray absorptiometry (DXA) measurements, smoke exposure was evaluated through serum cotinine levels, and multivariate logistic regression models were used to examine the association between smoke exposure and osteoporosis risk, adjusting for sociodemographic factors, health behaviours, and comorbidities.

RESULTS

The analysis comprised 4,140 postmenopausal women, and data analysis showed that active smoking was significantly associated with an increased risk of osteoporosis, with an adjusted odds ratio (OR) of 2.020 (95% confidence interval [CI]: 1.35-3.03), after adjusting for potential confounders. Additionally, age, race/ethnicity, socioeconomic status, marital status, and body mass index were identified as significant predictors of osteoporosis risk.

CONCLUSIONS

Smoke exposure, particularly active smoking, was associated with an elevated risk of osteoporosis among postmenopausal women in the United States. The findings underscore the need to address modifiable risk factors, such as smoking cessation, and implement targeted interventions to mitigate disparities in bone health.

Cadmium exposure and health outcomes:An umbrella review of meta-analyses

OBJECTIVE

This umbrella review synthesizes evidence from meta-analyses to assess the health outcomes associated with cadmium (Cd) exposure.

METHODS

Literature search was conducted in four Databases: PubMed, Embase, APA PsycNe, and the Cochrane Databases. Evaluating evidence strength via Assess Systematic Reviews 2 (AMSTAR 2), umbrella review methodology and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

RESULTS

Our review encompassed 79 non-overlapping studies, investigating 48 unique health outcomes through 113 independent effect sizes. Using the AMSTAR 2 tool, we found that 2 (3 %) meta-analyses were rated as high quality, 6 (8 %) as moderate quality, 38 as low quality, and 33 as very low quality. Applying the GRADE criteria, we observed that 1 (1 %) effect size was rated A (male fertility), 8 (7 %) were rated B (breast cancer, prostate cancer, hypertension, stroke, urolithiasis), 30 were rated C, and 74 were rated D. According to the umbrella review methodology, 5 (4 %) outcomes provided highly suggestive evidence, 13 (12 %) provided suggestive evidence, 51 provided weak evidence (class IV), and 44 had insufficient evidence for statistically significant results (class V). Meta-analyses on circulatory diseases, pregnancy outcomes, perinatal outcomes, skeletal and connective tissue diseases, neurological disorders, urinary system diseases, and male fertility had >80 % statistically significant results, while endocrine system diseases and mental and behavioral disorders had <33 %.

CONCLUSION

Cd exposure is significantly linked to various health outcomes, with implications for clinical practice and public health recommendations.

Biomarkers of aging: from molecules and surrogates to physiology and function

Many countries face an unprecedented challenge in aging demographics. This has led to an exponential growth in research on aging, which, coupled to a massive financial influx of funding in the private and public sectors, has resulted in seminal insights into the underpinnings of this biological process. However, critical validation in humans has been hampered by the limited translatability of results obtained in model organisms, additionally confined by the need for extremely time-consuming clinical studies in the ostensible absence of robust biomarkers that would allow monitoring in shorter time frames. In the future, molecular parameters might hold great promise in this regard. In contrast, biomarkers centered on function, resilience, and frailty are available at the present time, with proven predictive value for morbidity and mortality. In this review, the current knowledge of molecular and physiological aspects of human aging, potential antiaging strategies, and the basis, evidence, and potential application of physiological biomarkers in human aging are discussed.

Ambient air pollution and the risk of cancer: Evidence from global cohort studies and epigenetic-related causal inference

The correlation between air pollution and cancer incidence has been a longstanding concern, understanding the need to elucidate the specifics of this relationship. Thus, this study aimed to assess the association between exposure to air pollution and cancer incidence, and to identify the possible biological links between the two. We examined global cohort studies investigating the association between air pollution and cancer and performed a univariate Mendelian randomization (MR) analysis. Our analysis revealed that the presence of particulate matter (PM)2.5, PM10, NO2, and NOx substantially impacted the risk of developing cancer. MR analysis identified 130 CpGs sites associated with three ambient air pollutants that have significant casual effects on the risk of 14 cancer sites (false discovery rate<0.05). Gene annotation was conducted using g-Profiler by screening for single nucleotide polymorphisms significantly associated with outcome, followed by analysis of the gene interaction network using GeneMANIA, and visualization using igraph. In conclusion, this study demonstrates that air pollution has a significant impact on cancer incidence, provides strong evidence for an epigenetic causal link between the two, and provides new insights into the molecular mechanisms by which air pollution affects cancer development.

Association of cobalt exposure with all-cause and cardiovascular mortality in U.S. adults

BACKGROUND

Cobalt exposure is recognized as a potential risk factor for cardiovascular disease (CVD). However, the impact of cobalt exposure on mortality, particularly concerning CVD-related deaths, in the U.S. remains uncertain.

METHODS

Data from the National Health and Nutrition Examination Surveys (NHANES) spanning 1999-2018 were utilized to assess urinary cobalt levels in participants aged 20 years and older (n = 15,873). For the analysis of blood cobalt, data from NHANES covering the years 2015-2018 were considered, limited to participants aged 40 years and older (n = 6,692). The follow-up period extended until December 31, 2019.

RESULTS

The median values of ln-transformed urinary cobalt (creatinine corrected) and blood cobalt were - 1.10 ln(µg/g) and - 1.90 ln(µg/L), respectively. For urinary cobalt, during a median follow-up period of 130.0 months (interquartile range: 70.25-189.0), 2,304 participants died, with 613 deaths attributed to CVD. After adjusting for potential covariates, an increase in urinary cobalt level was significantly associated with a higher risk of all-cause mortality and CVD mortality (per 1 ln-unit increment, HR: 1.19, 95% CI: 1.07, 1.32; HR: 1.30, 95% CI: 1.06, 1.60, respectively). For blood cobalt, the adjusted HRs were 1.57 (95% CI: 1.15, 2.14) for all-cause mortality and 2.02 (95% CI: 1.10, 3.72) for CVD mortality.

CONCLUSIONS

In the U.S., low-level environmental cobalt exposure is a significant risk factor for both all-cause mortality and CVD mortality.

SYNOPSIS

Cobalt, a metallic element commonly encountered by the general population through food, water, or air inhalation, emerges as a novel risk factor for cardiovascular disease mortality.

Oxidative stress and inflammation mediate the adverse effects of cadmium exposure on all-cause and cause-specific mortality in patients with diabetes and prediabetes

BACKGROUND

The effect of cadmium exposure on mortality risk among individuals with diabetes and prediabetes remains unclear, particularly regarding potential mediation by oxidative stress and inflammation. This study aimed to investigate the associations of blood cadmium levels with all-cause, cardiovascular disease (CVD), and cancer mortality and the mediating effects of oxidative stress and inflammation biomarkers in patients with diabetes and prediabetes.

METHODS

In this prospective cohort study, we analyzed 17,687 adults with diabetes and prediabetes from the National Health and Nutrition Examination Survey (NHANES, 1999-2018). Nine biomarkers related to oxidative stress (gamma-glutamyl transferase [GGT], uric acid [UA], high-density lipoprotein [HDL], UA to HDL ratio [UHR]) and inflammation (neutrophil-lymphocyte ratio [NLR], monocyte-lymphocyte ratio [MLR], neutrophil-monocyte-lymphocyte ratio [NMLR], systemic inflammation response index [SIRI], systemic immune-inflammation index [SII]) were systematically assessed. Kaplan-Meier survival analysis, Cox proportional hazards models, and restricted cubic splines (RCS) were applied to evaluate the association of cadmium with mortality risk. Generalized linear models were used to assess the association of cadmium with oxidative stress and inflammation biomarkers, while Cox regression and RCS evaluated their effects on mortality. Causal mediation analysis identified biological pathways mediated by oxidative stress and inflammation. Stratified and sensitivity analyses were further employed to confirm the robustness of the results.

RESULTS

During 161,047.75 person-years of follow-up, 3562 deaths occurred, including 1214 from CVD and 680 from cancer. Higher blood cadmium levels were associated with increased risks of all-cause mortality (fully adjusted hazard ratio [HR]: 2.17; 95% confidence interval [CI] 1.69-2.79, comparing highest vs. lowest quartile), CVD mortality (HR 2.06; 95% CI 1.41-3.02), and cancer mortality (HR 2.38; 95% CI 1.47-3.85), without evidence of nonlinear relationship. Mediation analyses indicated that UA, NLR, MLR, NMLR, and SIRI partially mediated the associations of cadmium with all-cause and CVD mortality, although the mediated proportions were relatively modest (ranging from 1.4 to 4.8%). Additionally, GGT mediated a small fraction of the associations with all-cause and cancer mortality.

CONCLUSION

Cadmium exposure increases the risk of all-cause, CVD, and cancer mortality in patients with diabetes and prediabetes. Oxidative stress and inflammation appear to partially mediate this adverse effect. These findings emphasize the urgent need for targeted interventions to reduce cadmium-related mortality risks.

RESEARCH INSIGHTS

What is currently known about this topic? Cadmium exposure is linked to increased mortality. Oxidative stress and inflammation are critical in diabetes development and complications. What is the key research question? Does cadmium exposure increase mortality risk in patients with diabetes and prediabetes? Are oxidative stress and inflammation involved in mediating these effects? What is new? Cadmium exposure increases all-cause and cause-specific mortality in diabetes and prediabetes. Oxidative stress and inflammation mediate these associations. How might this study influence clinical practice? Monitor cadmium, oxidative stress, and inflammation to reduce mortality in diabetes and prediabetes.

Environment-wide association study of cardiovascular and all-cause mortality: Analysis of the National Health and Nutrition Examination Survey, 1999-2018

Environmental toxicants are increasingly suspected to influence cardiovascular (CV) and all-cause mortality, but previous studies mostly focused on one or a few chemicals. We examined the associations of a wide array of environmental chemicals with CV and all-cause mortality using an exposome-wide approach and the potential mediating role of inflammation in these associations. Data from the National Health and Nutrition Examination Survey (1999-2018) were randomly 60:40 split into a training set and a test set. The mortality rates were determined by the National Center for Health Statistics through a process of correlation with the National Death Index records. Based on the 10th revision of (ICD-10) codes, deaths due to heart disease (ICD 100-I09, I11, I13, and I20-I51) or cerebrovascular disease (I60-I69) were defined as CV mortality. Using the NHANES data, with a median 9.42-year follow-up period, we found that higher concentrations of 2-hydroxynaphthalene (2-NAP) and 2-hydroxyfluorene (2-FLU) in the urine, heavy metal cadmium (Cd), and cotinine in the blood were associated with increased risks of both CV and all-cause mortality. We further found 11 chemicals, including polycyclic aromatic hydrocarbons (1-hydroxynaphthalene, 3-hydroxyfluorene, and 9-hydroxyfluorene), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in the urine; hydroxycotinine, heavy metals lead, volatile organic compounds (benzene, ethylbenzene, styrene, toluene and 2,5-Dimethylfuran) in the blood were positively associated with all-cause mortality. Furthermore, we found that C-reactive protein levels partially mediate those associations. In summary, exposure to certain environmental chemicals was associated with CV and all-cause mortality, and C-reactive protein plays a mediation role in those associations. Our findings provided more evidence for preventing and controlling important environmental chemicals to improve people's health.

Associations of co-exposure to polycyclic aromatic hydrocarbons and vitamin D with early lung dysfunction: Mediating roles of metabolic score-visceral adiposity index

BACKGROUND

Preserved ratio impaired spirometry (PRISm) and airflow obstruction are recognized as critical early signs of chronic obstructive pulmonary disease (COPD). While these conditions arise from concurrent exposure to toxicants and essential nutrients, how vitamin D modifies the pulmonary toxicity induced by polycyclic aromatic hydrocarbons (PAHs) and the metabolic mechanisms involved is still unclear.

METHODS

Based on the National Health and Nutrition Examination Survey (NHANES) 2007-2012, data on urinary PAH metabolites (ΣOH-PAHs), serum vitamin D metabolite levels [Σ25(OH)D], and pulmonary function tests [forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and FEV1/FVC] from 2189 participants, including 369 subjects with early lung dysfunction, defined as PRISm or airflow obstruction. Multiple metabolic disorder indicators were calculated using biochemical markers. The interaction effects between vitamin D and PAHs were evaluated using multiple linear and logistic regression models. Causal mediation analyses and structural equation modeling were employed to investigate the mediating roles of metabolic indicators.

RESULTS

PAHs and vitamin D had opposite effects on lung function parameters [FEV1: β (95 CIs) = -0.01 (-0.02, -0.01) vs. 0.01 (0.01, 0.04); FVC: β (95 CIs) = -0.01 (-0.02, 0.01) vs. 0.04 (0.01, 0.06)] and risk of early lung dysfunction [OR (95 CIs) = 1.22 (1.06, 1.40) vs. 0.52 (0.37, 0.73)]. Decreased associations of ΣOH-PAHs with FEV1, FVC, and early lung dysfunction, as well as with metabolic score-visceral adiposity index (MSV) were visualized with increased Σ25(OH)D among subjects with body mass index (BMI) < 28 kg/m2. Furthermore, 2.18 %, 18.20 %, 5.70 %, and 4.70 % of the associations of co-exposure to ΣOH-PAHs and Σ25(OH)D with FEV1, FVC, FEV1/FVC, and early lung dysfunction disease were mediated by MSV.

CONCLUSIONS

Our findings indicated that vitamin D antagonizes the hazardous effects of PAHs on early lung dysfunction by metabolic alteration, providing new insight into the identification of the underlying high-risk populations and accessible prevention and intervention measures for attenuating PAH-induced lung dysfunction.

Lipid accumulation product mediating the association between uranium and cerebrovascular diseases mortality: Evidence from National Health and Nutrition Examination Survey

This study investigated the potential association between uranium exposure and mortality from cerebrovascular diseases, with a focus on the mediating effects of lipid indicators. Employing recommended sampling weights to account for National Health and Nutrition Examination Survey' complex survey design, this analysis drew from data collected between 2005 and 2016. The study examined the impact of uranium on mortality from cerebrovascular diseases using various statistical approaches, including Cox regression to assess linear relationships within metal mixtures. It also evaluated the role of lipid-adjusted plutonium (LAP) as a mediator and verified the persistence of associations across different subgroups. The study encompassed 4312 participants and established a significant direct link between uranium levels and mortality from cerebrovascular diseases (hazard ratio (95%CI) = 20.4243 (20.1347-20.7181), P = .0266). It also identified LAP as a mediating factor in the relationship, accounting for a mediated proportion of 1.35%. The findings highlight a pivotal connection between uranium exposure and increased mortality due to cerebrovascular diseases, with LAP playing a significant intermediary role.

Lead (Pb) in biological samples in association with cancer risk and mortality: A systematic literature review

BACKGROUND AND AIM

Lead (Pb) is a toxic heavy metal and pervasive environmental contaminant, and a class 2 A carcinogen according to the IARC classification, yet its link with cancer at several body sites remains uncertain. Here, we aimed at summarizing the scientific evidence regarding its association with cancer risk and mortality, focusing on studies that carried out Pb measurements in biological samples.

METHODS

We reviewed articles published in PubMed and EMBASE until January 2nd, 2024, that quantified the epidemiological association between Pb measured in blood, urine, nails, and other biological media, and cancer risk and mortality (overall and by cancer site/type).

RESULTS

We included 46 articles (out of 8022 screened) published in 1995-2023 and reporting on investigations conducted in fifteen countries. In terms of design, 20 were prospective, 24 were retrospective case-control studies, and 2 were cross-sectional. Pb levels were determined in blood in the majority of studies (n=28). The most consistent evidence was for the association of Pb with cancer of the gastrointestinal tract, particularly the oesophagus, stomach (RR ranging from 0.80 to 2.66), colon-rectum, and pancreas; and of the bladder and urinary tract (RR from 1.10 to 2.89). For other specific malignancies, the data were conflicting or too limited to draw reliable conclusions. Finally, increased Pb concentration in blood and urine was consistently associated with higher overall cancer incidence and mortality.

CONCLUSIONS

Lead is a widespread and highly persistent environmental pollutant associated with cancer at multiple body sites. Comprehensive primary prevention interventions aiming at reducing opportunities for Pb exposure need to be continuously promoted and implemented.

Cadmium in biological samples and site-specific cancer risk and mortality: A systematic review of original articles and meta-analyses

BACKGROUND

Cadmium (Cd) is classified as a class 1 carcinogen by the IARC, yet uncertainty persists regarding the total burden of cancer (incidence and mortality) caused by exposure to it, due to the still limited evidence with regard to its aetiological role in cancer at several body sites.

OBJECTIVES AND METHODS

We searched PubMed and EMBASE for meta-analyses and original articles published by February 1st, 2024, that focused on the link between cadmium measured in biological samples (blood, urine, finger-/toe-nails, and hair) and site-specific cancer risk and mortality.

RESULTS

We included 9 meta-analyses and 57 original articles (of these, the design was retrospective in 38 and prospective in 19, and Cd levels were quantified in blood, n=33, urine, n=19, both blood and urine, n=2, or finger-/toenail, n=3). Current data consistently suggest a causal role of exposure to cadmium in pancreas, lung, and bladder carcinogenesis. Total cancer risk and mortality are also positively correlated with Cd levels in biological samples. The evidence is weak or inconclusive for the remaining cancer sites (including breast and prostate), mostly due to the limited number of studies available to date and/or methodological limitations.

DISCUSSION

Exposure to cadmium poses a risk for increased cancer incidence and mortality. Cadmium-related cancer burden might indeed be currently underestimated, as the amount of available evidence for most cancer sites and types is currently limited, and more research in the field is warranted. Continuing efforts to contain Cd pollution and mitigate associated health risk are also needed.

Impact of the environmental pollution on cardiovascular diseases: From epidemiological to molecular evidence

Environmental pollution poses a significant threat to human health, particularly concerning its impact on cardiovascular diseases (CVDs). This review synthesizes epidemiological and molecular evidence to elucidate the intricate relationship between environmental pollutants and CVDs. Epidemiological studies highlight the association between exposure to air, water, and soil pollutants and increased CVD risk, including hypertension, coronary artery disease, and stroke. Furthermore, molecular investigations unravel the underlying mechanisms linking pollutant exposure to CVD pathogenesis, such as oxidative stress, inflammation, endothelial dysfunction, and autonomic imbalance. Understanding these molecular pathways is crucial for developing targeted interventions and policy strategies to mitigate the adverse effects of environmental pollution on cardiovascular health. By integrating epidemiological and molecular evidence, this review provides insights into the complex interplay between environmental factors and CVDs, emphasizing the urgent need for comprehensive preventive measures and environmental policies to safeguard public health.

Cadmium exposure in infants and children: toxicity, health effects, dietary risk assessment and mitigation strategies

As a non-essential metal, cadmium (Cd) poses a significant threat to food safety and public health. This risk is particularly pronounced for infants and young children due to their high food consumption relative to body weight and immature physiological systems. This review examines the health risks associated with Cd exposure, particularly during the prenatal period through adolescence. It evaluates the prevalence of Cd-rich foods in children's diets and their intake levels across various countries. The review demonstrates that Cd exposure is associated with neurodevelopmental disorders, immune dysfunction, and cardiovascular diseases. It also highlights geographic differences in exposure, with some Asian countries, such as Thailand and China, exhibiting higher overall levels of Cd intake among children compared to other regions. This review presents several recommendations to mitigate Cd intake during early childhood, including reducing the Cd content in food, inhibiting Cd absorption, and promoting its excretion from the body. To minimize the risk of dietary Cd intake in children, it is recommended that stringent regulations of Cd limits in children's food be implemented, alongside a coordinated multi-stakeholder effort. This review provides important insights into effective public health policy development, laying the foundation for achieving broader public health goals.

Relationship between mixed exposure to phenyl hydroxides, polycyclic aromatic hydrocarbons, and phthalates and the risk of arthritis

BACKGROUND

To determine the relationship between mixed exposure to three types of endocrine-disrupting chemicals (EDCs), namely phenyl hydroxides, polycyclic aromatic hydrocarbons (PAHs), and phthalates (PAEs), and risk of arthritis.

METHODS

Participants were selected from National Health and Nutrition Examination Survey (NHANES). The relationships between the urinary concentrations of phenyl hydroxides, PAHs, and PAEs and the risk of arthritis were analyzed by generalized linear regression model. The mixed exposure to these EDCs and the risk of arthritis was analyzed by weighted quantile sums (WQSs) and Bayesian kernel machine regression (BKMR) model.

RESULTS

Our analysis showed that participants with urinary benzophenone-3 and methylparaben concentrations in the highest quartile (Q4) had an increased risk of arthritis compared with those in Q1. For each one-unit increase in the natural logarithm-converted urinary concentrations of 1-hydroxynapthalene and 2-hydroxynapthalene, the risk of arthritis increased by 5% and 8%, respectively. Chemical mixing index coefficients were significantly associated with risk of arthritis in both WQS positive- and negative-constraint models. In the BKMR model, there was a significant positive correlation between mixed exposure and the risk of arthritis.

CONCLUSION

Mixed exposure to phenyl hydroxides, PAHs, and PAEs increased the risk of arthritis, with exposure to PAHs being the key factor.

Association of Urinary Glyphosate with All-Cause Mortality and Cardiovascular Mortality among Adults in NHANES 2013-2018: Role of Alkaline Phosphatase

Glyphosate is the most widely used herbicide in the world. This study aimed to evaluate the relationships among urinary glyphosate, all-cause mortality and cardiovascular diseases (CVD)-related mortality in the general US population of adults, and to determine the role of alkaline phosphatase (ALP), an inflammation marker that is associated with glyphosate exposure, in these relationships. Subjects from the National Health and Nutrition Examination Survey (NHANES) 2013-2018 cycles were included. Survey-weighted Cox regression analysis was applied to estimate the relationship of glyphosate with overall and CVD mortalities. Restricted cubic spline (RCS) analysis was utilized to detect the linearity of associations. The intermediary role of ALP was explored by mediation analysis. Our results found consistent and positive associations of glyphosate with all-cause mortality (HR: 1.29, 95%CI: 1.05-1.59) and CVD mortality (HR: 1.32, 95%CI: 1.02-1.70). RCS curves further validated linear and positive dose-dependent relationships between glyphosate and mortality-related outcomes. Moreover, serum ALP was identified as a mediator in these associations and explained 12.1% and 14.0% of the total associations between glyphosate and all-cause death and CVD death risk, respectively. Our study indicated that glyphosate was associated with increased all-cause and CVD mortality in humans. Increased ALP may play an essential role in these associations.

Low-grade systemic inflammation links heavy metal exposures to mortality: A multi-metal inflammatory index approach

Certain heavy metals have been correlated to an elevated risk of inflammation-related diseases and mortality. Nevertheless, the intricate relationships between metal exposure, inflammation and mortality remain unknown. We included 3741 adults with measurements of ten urinary heavy metals in the National Health and Nutritional Examination Survey (NHANES) 2005-2010, followed up to December 31, 2019. Low-grade systemic inflammation was evaluated by various markers, including C-reactive protein (CRP) and ratios derived from regular blood tests. We assessed associations between heavy metal and all-cause mortality using multivariate COX regressions. Then we assessed the mediation effect of low-grade systemic inflammation on the associations via Sobel Test. To gauge the systemic inflammatory potential of the multi-metal mixture and its correlation with all-cause mortality, a Metal Mixture Inflammatory Index (MMII) was developed using reduced rank regression (RRR) models. The association between MMII and all-cause mortality was explored via multivariate COX regressions. Cadmium, antimony and uranium displayed positive associations with mortality, with hazard ratios (HR) ranging from 1.18 to 1.46 (all P-FDR < 0.05). Mediation analyses revealed that the associations between specific heavy metals (cadmium and antimony) and mortality risk were slightly mediated by the low-grade systemic inflammation markers, with mediation proportions ranging from 3.11 % to 5.38 % (all P < 0.05). MMII, the weighted sum of 9 heavy metals, significantly predicted platelet-to-lymphocyte ratio (PLR) and CRP (β = 0.10 and 1.16, all P < 0.05), was positively associated with mortality risk (HR 1.28, 95 % CI 1.14 to 1.43). Exposure to heavy metals might increase all-cause mortality, partly mediated by low-grade systemic inflammation. MMII, designed to assess the potential systemic inflammatory effects of exposure to multiple heavy metals, was closely related to the all-cause mortality risk. This study introduces MMII as an approach to evaluating co-exposure and its potential health effects comprehensively.

Associations of phthalates with accelerated aging and the mitigating role of physical activity

Phthalates are positioned as potential risk factors for health-related diseases. However, the effects of exposure to phthalates on accelerated aging and the potential modifications of physical activity remain unclear. A total of 2317 participants containing complete study-related information from the National Health and Nutrition Examination Survey 2007-2010 were included in the current study. We used two indicators, the Klemera-Doubal method biological age acceleration (BioAgeAccel) and phenotypic age acceleration (PhenoAgeAccel), to assess the accelerated aging status of the subjects. Multiple linear regression (single pollutant models), weighted quantile sum (WQS) regression, Quantile g-computation, and Bayesian kernel machine regression (BKMR) models were utilized to explore the associations between urinary phthalate metabolites and accelerated aging. Three groups of physical activity with different intensities were used to evaluate the modifying effects on the above associations. Results indicated that most phthalate metabolites were significantly associated with BioAgeAccel and PhenoAgeAccel, with effect values (β) ranging from 0.16 to 0.21 and 0.16-0.37, respectively. The WQS indices were positively associated with BioAgeAccel (0.33, 95% CI: 0.11, 0.54) and PhenoAgeAccel (0.50, 95% CI: 0.19, 0.82). Quantile g-computation indicated that phthalate mixtures were associated with accelerated aging, with effect values of 0.15 (95% CI: 0.02, 0.28) for BioAgeAccel and 0.39 (95% CI: 0.12, 0.67) for PhenoAgeAccel respectively. The BKMR models indicated a significant positive association between the concentrations of urinary phthalate mixtures with the two indicators. In addition, we found that most phthalate metabolites showed the strongest effects on accelerated aging in the no physical activity group and that the effects decreased gradually with increasing levels of physical activity (P < 0.05 for trend). Similar results were also observed in the mixed exposure models (WQS and Quantile g-computation). This study indicates that phthalates exposure is associated with accelerated aging, while physical activity may be a crucial barrier against phthalates exposure-related aging.

Estimating lead-attributable mortality burden by socioeconomic status in the USA

BACKGROUND

This study aimed to estimate population-level and state-level lead-attributable mortality burdens stratified by socioeconomic status (SES) class in the USA.

METHODS

Based on the National Health and Nutrition Examination Survey (NHANES), we constructed individual-level SES scores from income, employment, education and insurance data. We assessed the association between the blood lead levels (BLL) and all-cause mortality by Cox regression in the NHANES cohort (n = 31 311, 4467 deaths). With estimated hazard ratios (HR) and prevalences of medium (2-5 μg/dL) and high (≥ 5 μg/dL) BLL, we computed SES-stratified population-attributable fractions (PAFs) of all-cause mortality from lead exposure across 1999-2019. We additionally conducted a systematic review to estimate the lead-attributable mortality burden at state-level.

RESULTS

The HR for every 2-fold increase in the BLL decreased from 1.23 (1.10-1.38) for the lowest SES class to 1.05 (0.90-1.23) for the highest SES class. Across all SES quintiles, medium BLL exhibited a greater mortality burden. Individuals with lower SES had higher lead-attributable burdens, and such disparities haver persisted over the past two decades. In 2017-19, annually 67 000 (32 000-112 000) deaths in the USA were attributable to lead exposure, with 18 000 (2000-41 000) of these deaths occurring in the lowest SES class. Substantial disparities in the state-level mortality burden attributable to lead exposure were also highlighted.

CONCLUSIONS

These findings suggested that disparities in lead-attributable mortality burden persisted within US adults, due to heterogeneities in the effect sizes of lead exposure as well as in the BLL among different SES classes.

High serum copper as a risk factor of all-cause and cause-specific mortality among US adults, NHANES 2011-2014

Background

Several studies have shown that serum copper levels are related to coronary heart disease, diabetes, and cancer. However, the association of serum copper levels with all-cause, cause-specific [including cardiovascular disease (CVD) and cancer] mortality remains unclear.

Objectives

This study aimed to prospectively examine the association of copper exposure with all-cause, CVD, and cancer mortality among US adults.

Methods

The data for this analysis was obtained from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014. Mortality from all-causes, CVD, and cancer mortality was linked to US National Death Index mortality data. Cox regression models were used to estimate the association between serum copper levels and all-cause, CVD, and cancer mortality.

Results

A total of 2,863 adults were included in the main study. During the mean follow-up time of 81.2 months, 236 deaths were documented, including 68 deaths from cardiovascular disease and 57 deaths from cancer. The weighted mean overall serum copper levels was 117.2 ug/L. After adjusting for all of the covariates, compared with participants with low (1st tertile, <103 μg/L)/medium (2st tertile, 103-124 μg/L) serum copper levels, participants with high serum copper levels (3rd tertile, ≥124 μg/L) had a 1.75-fold (95% CI, 1.05-2.92)/1.78-fold (1.19,2.69) increase in all-cause mortality, a 2.35-fold (95% CI, 1.04-5.31)/3.84-fold (2.09,7.05) increase in CVD mortality and a 0.97-fold (95% CI, 0.28-3.29)/0.86-fold (0.34,2.13) increase in cancer mortality. In addition, there was a linear dose-response association between serum copper concentration with all-cause and CVD mortality (P for nonlinear > 0.05).

Conclusions

This prospective study found that serum copper concentrations were linearly associated with all-cause and CVD mortality in US adults. High serum copper levels is a risk factor for all-cause and CVD mortality.

The mitochondrial link: Phthalate exposure and cardiovascular disease

Phthalates' pervasive presence in everyday life poses concern as they have been revealed to induce perturbing health defects. Utilized as a plasticizer, phthalates are riddled throughout many common consumer products including personal care products, food packaging, home furnishings, and medical supplies. Phthalates permeate into the environment by leaching out of these products which can subsequently be taken up by the human body. It is previously established that a connection exists between phthalate exposure and cardiovascular disease (CVD) development; however, the specific mitochondrial link in this scenario has not yet been described. Prior studies have indicated that one possible mechanism for how phthalates exert their effects is through mitochondrial dysfunction. By disturbing mitochondrial structure, function, and signaling, phthalates can contribute to the development of the foremost cause of death worldwide, CVD. This review will examine the potential link among phthalates and their effects on the mitochondria, permissive of CVD development.

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.

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

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

Toxicological Effects of Naturally Occurring Endocrine Disruptors on Various Human Health Targets: A Rapid Review

Endocrine-disrupting compounds are chemicals that alter the normal functioning of the endocrine system of living organisms. They can be natural (N-EDCs) or synthetic compounds (S-EDCs). N-EDCs can belong to different groups, such as phytoestrogens (PEs), including flavonoids, or mycotoxins originating from plants or fungi, and cyanotoxins, derived from bacteria. Humans encounter these substances in their daily lives. The aim of this rapid review (RR) is to provide a fine mapping of N-EDCs and their toxicological effects on human health in terms of various medical conditions or adverse consequences. This work is based on an extensive literature search and follows a rigorous step-by-step approach (search strategy, analysis strategy and data extraction), to select eligible papers published between 2019 and 2023 in the PubMed database, and to define a set of aspects characterizing N-EDCs and the different human target systems. Of the N-EDCs identified in this RR, flavonoids are the most representative class. Male and female reproductive systems were the targets most affected by N-EDCs, followed by the endocrine, nervous, bone and cardiovascular systems. In addition, the perinatal, pubertal and pregnancy periods were found to be particularly susceptible to natural endocrine disruptors. Considering their current daily use, more toxicological research on N-EDCs is required.

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.

Development of interpretable machine learning models associated with environmental chemicals to predict all-cause and specific-cause mortality：A longitudinal study based on NHANES

Limited information is available on potential predictive value of environmental chemicals for mortality. Our study aimed to investigate the associations between 43 of 8 classes representative environmental chemicals in serum/urine and mortality, and further develop the interpretable machine learning models associated with environmental chemicals to predict mortality. A total of 1602 participants were included from the National Health and Nutrition Examination Survey (NHANES). During 154,646 person-months of follow-up, 127 deaths occurred. We found that machine learning showed promise in predicting mortality. CoxPH was selected as the optimal model for predicting all-cause mortality with time-dependent AUROC of 0.953 (95%CI: 0.951-0.955). Coxnet was the best model for predicting cardiovascular disease (CVD) and cancer mortality with time-dependent AUROCs of 0.935 (95%CI: 0.933-0.936) and 0.850 (95%CI: 0.844-0.857). Based on clinical variables, adding environmental chemicals could enhance the predictive ability of cancer mortality (P < 0.05). Some environmental chemicals contributed more to the models than traditional clinical variables. Combined the results of association and prediction models by interpretable machine learning analyses, we found urinary methyl paraben (MP) and urinary 2-napthol (2-NAP) were negatively associated with all-cause mortality, while serum cadmium (Cd) was positively associated with all-cause mortality. Urinary bisphenol A (BPA) was positively associated with CVD mortality.

Association of phthalate exposure with all-cause mortality across renal function status: The U.S. National Health and Nutrition Examination Survey, 2005-2018

BACKGROUND

Wide phthalate exposure has been associated with both declines in renal function and an elevated risk of mortality. Whether phthalate-associated risk of premature mortality differs by renal function status remains unclear.

METHODS

This study included 9605 adults from the U.S. National Health and Nutrition Examination Survey. Urinary concentrations of 11 phthalate metabolites were assessed using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. According to estimated glomerular filtration rate (eGFR), participants were grouped as having normal or modestly declined renal functions, or chronic kidney disease (CKD). Multivariable Cox regression models estimated all-cause mortality associated with phthalate exposure, overall and by renal function status.

RESULTS

Overall, Mono-n-butyl phthalate (MnBP), Mono-benzyl phthalate (MBzP), Mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and Mono-(2-ethyl-5-carbox-ypentyl) phthalate (MECPP) were associated with an elevated risk of mortality (P-trend across tertile <0.05). Moreover, significant interactions were observed between eGFR and MEHHP, MEOHP, MECPP, DEHP in the whole population (P for interactions <0.05). After stratification by renal function, total Di (2-ethylhexyl) phthalate (DEHP) was additionally found to be associated with mortality risk in the CKD group (HR = 1.12; 95% CI: 1.01, 1.25). Co-exposure to the 11 phthalate metabolites was associated with a higher risk of all-cause mortality in the CKD (HR = 1.47; 95% CI: 1.18, 1.84) and modestly declined renal function group (HR = 1.25; 95% CI: 1.09, 1.44).

CONCLUSIONS

The associations between phthalate exposure and risk of all-cause mortality were primarily observed in CKD patients, reinforcing the need for monitoring phthalate exposure in this patient population.

Association of organophosphate flame retardants with all-cause and cause-specific mortality among adults aged 40 years and older

The longitudinal associations of urinary concentrations of diphenyl phosphate (DPHP), bis(2-chloroethyl) phosphate (BCEP), and bis(1,3-dichloro-2-propyl) phosphate (BDCPP) with all-cause, cardiovascular, and cancer mortality in a population of adults aged 40 years and older are still unclear. A total of 3238 participants were included in this cohort study. Urinary BCEP levels were positively associated with all-cause mortality and cardiovascular mortality. Specifically, a logarithmic increase in BCEP concentration was related to a 26 % higher risk of all-cause mortality and a 32 % higher risk of cardiovascular mortality. No significant associations were observed for DPHP and BDCPP in relation to mortality. Doseresponse analysis confirmed the linear associations of BCEP with all-cause and cardiovascular mortality and the nonlinear inverted U-shaped association between DPHP exposure and all-cause mortality. Notably, the economic burden associated with BCEP exposure was estimated, and it was shown that concentrations in the third tertile of BCEP exposure incurred approximately 507 billion dollars of financial burden for all-cause mortality and approximately 717 billion dollars for cardiovascular mortality. These results highlight the importance of addressing exposure to BCEP and its potential health impacts on the population. More research is warranted to explore the underlying mechanisms and develop strategies for reducing exposure to this harmful chemical.

Association between co-exposure to phenols, phthalates, and polycyclic aromatic hydrocarbons with the risk of frailty

The phenomenon of population aging has brought forth the challenge of frailty. Nevertheless, the contribution of environmental exposure to frailty remains ambiguous. Our objective was to investigate the association between phenols, phthalates (PAEs), and polycyclic aromatic hydrocarbons (PAHs) with frailty. We constructed a 48-item frailty index using data from the National Health and Nutrition Examination Survey (NHANES). The exposure levels of 20 organic contaminants were obtained from the survey circle between 2005 and 2016. The association between individual organic contaminants and the frailty index was assessed using negative binomial regression models. The combined effect of organic contaminants was examined using weighted quantile sum (WQS) regression. Dose-response patterns were modeled using generalized additive models (GAMs). Additionally, an interpretable machine learning approach was employed to develop a predictive model for the frailty index. A total of 1566 participants were included in the analysis. Positive associations were observed between exposure to MIB, P02, ECP, MBP, MHH, MOH, MZP, MC1, and P01 with the frailty index. WQS regression analysis revealed a significant increase in the frailty index with higher levels of the mixture of organic contaminants (aOR, 1.12; 95% CI, 1.05-1.20; p < 0.001), with MIB, ECP, COP, MBP, P02, and P01 identified as the major contributors. Dose-response relationships were observed between MIB, ECP, MBP, P02, and P01 exposure with an increased risk of frailty (both with p < 0.05). The developed predictive model based on organic contaminants exposure demonstrated high performance, with an R2 of 0.9634 and 0.9611 in the training and testing sets, respectively. Furthermore, the predictive model suggested potential synergistic effects in the MIB-MBP and P01-P02 pairs. Taken together, these findings suggest a significant association between exposure to phthalates and PAHs with an increased susceptibility to frailty.