Effects of gaseous and solid constituents of air pollution on endothelial function

Toxicological effects of long-term continuous exposure to ambient air on human bronchial epithelial Calu-3 cells exposed at the air-liquid interface

Air pollution significantly contributes to the global burden of respiratory and cardiovascular diseases. While single source/compound studies dominate current research, long-term, multi-pollutant studies are crucial to understanding the health impacts of environmental aerosols. Our study aimed to use the first air-liquid interface (ALI) aerosol exposure system adapted for long-term in vitro exposures for ambient air in vitro exposure. The automated exposure system was adapted to enable long-term cell exposure. ALI human bronchial epithelial cells (Calu-3) were continuously exposed for 72 h to the ambient air from a European urban area (3 independent exposures). Experimental evaluation included comprehensive toxicological assessments coupled to physical- and chemical-characterization of the aerosol. Exposure to ambient air resulted in increased significant cytotoxicity and a non-significant decrease in cell viability. Differential gene expressions were indicated for genes related to inflammation (IL1B, IL6) and to xenobiotic metabolism (CYP1A1, CYP1B1) with possible correlations to the PM2.5 content. Common air pollutants were identified such as the carcinogenic benz[a]pyrene (≤ 3.4 ng m-3 / 24h) and PM2.5 (≤ 11.6 μg m-3 / 24h) with a maximum particle number mean of 4.4 × 10-3 m3/ 24h. For the first time, ALI human lung epithelial cells were exposed for 72 h to continuous airflow of ambient air. Despite direct exposure to ambient aerosols, only small decreased in cell viability and gene expression changes was observed. We propose this experimental set-up combining comprehensive aerosol characterization and long-term continuous ALI cell exposure for the identification of hazardous compounds or compound mixtures in ambient air.

[The effects of environmental stressors on cardiovascular health]

Noncommunicable diseases (NCDs) are responsible for the premature deaths of more than 38 million people each year, making them the leading cause of the global burden of disease, accounting for 70% of global mortality. The majority of these deaths are caused by cardiovascular diseases. The risk of NCDs is closely related to exposure to environmental stressors such as air pollution, noise pollution, artificial light at night, and climate change, including extreme heat, sandstorms, and wildfires. In addition to the traditional risk factors for cardiovascular diseases such as diabetes, high blood pressure, smoking, hypercholesterolemia and genetic predisposition, there is increasing evidence that physicochemical factors in the environment significantly contribute to the high NCD numbers. In addition, urbanization is related to the accumulation and intensification of these stressors. This expert review will summarize the epidemiology and pathophysiology of environmental stressors with a focus on cardiovascular NCDs. In addition, solutions and measures to mitigate the effects of environmental risks, especially concerning cardiovascular diseases, will be discussed.

The impacts of mask-wearing regulations on stroke morbidity and mortality: a population-based retrospective cohort study in China

BACKGROUND

It is common to protect people from air pollution by wearing masks, but how much of its health effect on cardiovascular diseases (CVDs) is unknown. This study aimed to determine whether the mask intervention associated with decrease in stroke morbidity and mortality.

METHODS

We conducted a retrospective cohort study comprising 7.8 million residents in Weifang, China from 2016 to 2022. The primary outcome was the daily stroke morbidity and mortality. An interrupted time series analysis, adjusting for underlying secular trends, seasonal patterns, air pollution, meteorological factors, health services utilization and road lockdowns, was performed to assess the immediate and gradual changes of stroke morbidity and mortality after the implementation of mask-wearing regulations.

RESULTS

During the study period, 400,245 incident cases and 64,719 deaths of stroke were identified. Findings indicated a 5.5% (95% confidence interval (CI): 0.8%-10.0%) immediate and a 14.3% annual gradual (95% CI: 12.7%-15.8%) reduction were observed in stroke morbidity after the implementation of the regulations, which resulted in an overall reduction of 38.6% (95% CI: 34.1%-43.2%) within 33 months of follow-up. Similarly, there was the gradual decrease in stroke mortality. It resulted in an overall post-intervention decrease of 8.4% (95% CI, 1.6%-15.1%). The subgroup analyses indicated that overall post-regulation reductions in stroke morbidity were observed across all age groups, genders, and subtypes. However, the overall reduction in stroke mortality among male and those with hemorrhagic stroke was not statistically significant.

CONCLUSION

These findings have implications for policy makers and public health experts seeking to reduce burden of stroke morbidity and mortality at the population level through personal protection measure in regions with severe air pollution.

The associations between exposure to ambient air pollution and coagulation markers and the potential effects of DNA methylation

Previous studies have illustrated the pivotal role of coagulation biomarkers in the link between air pollution and cardiovascular disease (CVD). However, inconsistencies remain in the conclusions, with limited studies conducted in rural areas of China. We conducted a panel study in rural areas of Henan Province, China. Considering the potential effect modifications of atherosclerotic cardiovascular disease (ASCVD) risks, 104 participants were enrolled, comprising two matched groups: 52 with high ASCVD risks and 52 with low ASCVD risks. DNA methylation at CpG sites and coagulation indices were measured for all participants. Linear mixed-effect regression models were used to evaluate the associations between ambient air pollution, coagulation biomarkers, and DNA methylation. We observed that for every 5-day standard deviation (SD) increment of PM2.5 (11.91 μg/m³) and PM10 (13.65 μg/m³), fibrinogen increased by 7.70 % (95 %CI: 2.27, 13.12) and 8.50 % (95 %CI: 2.46, 14.55), respectively. SO2 (6.95 μg/m³) was associated with 40.25 % (95 %CI: 14.83, 65.67) increase in plasminogen activator inhibitor-1 (PAI-1). Decreased methylation at CpG sites was associated with exposure to air pollution. However, DNA methylation did not mediate the association between ambient air pollution and coagulation. Our study revealed the harmful impact of ambient air pollution on coagulation function but found no significant mediation effects of DNA methylation.

Airborne Nanoparticle Concentrations Are Associated with Increased Mortality Risk in Canada's Two Largest Cities

Rationale: Outdoor fine particulate air pollution (particulate matter with an aerodynamic diameter ⩽2.5 μm; PM2.5) contributes to millions of deaths around the world each year, but much less is known about the long-term health impacts of other particulate air pollutants, including ultrafine particles (a.k.a. nanoparticles), which are in the nanometer-size range (<100 nm), widespread in urban environments, and not currently regulated. Objectives: We sought to estimate the associations between long-term exposure to outdoor ultrafine particles and mortality. Methods: Outdoor air pollution levels were linked to the residential addresses of a large, population-based cohort from 2001 to 2016. Associations between long-term exposure to outdoor ultrafine particles and nonaccidental and cause-specific mortality were estimated using Cox proportional hazards models. Measurements and Main Results: An increase in long-term exposure to outdoor ultrafine particles was associated with an increased risk of nonaccidental mortality (hazard ratio = 1.073; 95% confidence interval = 1.061-1.085) and cause-specific mortality, the strongest of which was respiratory mortality (hazard ratio = 1.174; 95% confidence interval = 1.130-1.220). We estimated the mortality burden for outdoor ultrafine particles in Montreal and Toronto, Canada, to be approximately 1,100 additional nonaccidental deaths every year. Furthermore, we observed possible confounding by particle size, which suggests that previous studies may have underestimated or missed important health risks associated with ultrafine particles. Conclusions: As outdoor ultrafine particles are not currently regulated, there is great potential for future regulatory interventions to improve population health by targeting these common outdoor air pollutants.

PM2.5-mediated cardiovascular disease in aging: Cardiometabolic risks, molecular mechanisms and potential interventions

Air pollution, particularly fine particulate matter (PM2.5) with <2.5 μm in diameter, is a major public health concern. Studies have consistently linked PM2.5 exposure to a heightened risk of cardiovascular diseases (CVDs) such as ischemic heart disease (IHD), heart failure (HF), and cardiac arrhythmias. Notably, individuals with pre-existing age-related cardiometabolic conditions appear more susceptible. However, the specific impact of PM2.5 on CVDs susceptibility in older adults remains unclear. Therefore, this review addresses this gap by discussing the factors that make the elderly more vulnerable to PM2.5-induced CVDs. Accordingly, we focused on physiological aging, increased susceptibility, cardiometabolic risk factors, CVDs, and biological mechanisms. This review concludes by examining potential interventions to reduce exposure and the adverse health effects of PM2.5 in the elderly population. The latter includes dietary modifications, medications, and exploration of the potential benefits of supplements. By comprehensively analyzing these factors, this review aims to provide a deeper understanding of the detrimental effects of PM2.5 on cardiovascular health in older adults. This knowledge can inform future research and guide strategies to protect vulnerable populations from the adverse effects of air pollution.

Fine particulate matter and ovarian health: A review of emerging risks

Fine particulate matter (PM2.5) pollution has raised significant public concerns, especially for vulnerable populations. Studies have indicated the association between PM2.5 and ovarian disorders, although the mechanisms underlying the effects have not yet been fully elucidated. In this review, we elucidated three main conditions pertaining to ovarian function that may result from exposure to PM2.5: diminished ovarian reserve, polycystic ovary syndrome, and infertility. Specific effects of ovarian disorders caused by PM2.5 are discussed, including reactive oxygen species, apoptosis, DNA damage, and inflammation.

Gestational exposure to wildfire PM2.5 and its specific components and the risk of gestational hypertension and eclampsia in the southwestern United States

In the southwestern United States, the frequency of summer wildfires has elevated ambient PM2.5 concentrations and rates of adverse birth outcomes. Notably, hypertensive disorders in pregnancy (HDP) constitute a significant determinant associated with maternal mortality and adverse birth outcomes. Despite the accumulating body of evidence, scant research has delved into the correlation between chemical components of wildfire PM2.5 and the risk of HDP. Derived from data provided by the National Center for Health Statistics, singleton births from >2.68 million pregnant women were selected across 8 states (Arizona, AZ; California, CA, Idaho, ID, Montana, MT; Nevada, NV; Oregon, OR; Utah, UT, and Wyoming, WY) in the southwestern US from 2001 to 2004. A spatiotemporal model and a Goddard Earth Observing System chemical transport model were employed to forecast daily concentrations of total and wildfire PM2.5-derived exposure. Various modeling techniques including unadjusted analyses, covariate-adjusted models, propensity-score matching, and double robust typical logit models were applied to assess the relationship between wildfire PM2.5 exposure and gestational hypertension and eclampsia. Exposure to fire PM2.5, fire-sourced black carbon (BC) and organic carbon (OC) were associated with an augmented risk of gestational hypertension (ORPM2.5 = 1.125, 95 % CI: 1.109,1.141; ORBC = 1.247, 95 % CI: 1.214,1.281; OROC = 1.153, 95 % CI: 1.132, 1.174) and eclampsia (ORPM2.5 = 1.217, 95 % CI: 1.145,1.293; ORBC = 1.458, 95 % CI: 1.291,1.646; OROC = 1.309, 95 % CI: 1.208,1.418) during the pregnancy exposure window with the strongest effect. The associations were stronger that the observed effects of ambient PM2.5 in which the sources primarily came from urban emissions. Social vulnerability index (SVI), education years, pre-pregnancy diabetes, and hypertension acted as effect modifiers. Gestational exposure to wildfire PM2.5 and specific chemical components (BC and OC) increased gestational hypertension and eclampsia risk in the southwestern United States.

Short-term ozone exposure on stroke mortality and mitigation by greenness in rural and urban areas of Shandong Province, China

BACKGROUND

Short-term exposure to ozone (O3) has been associated with higher stroke mortality, but it is unclear whether this association differs between urban and rural areas. The study aimed to compare the association between short-term exposure to O3 and ischaemic and haemorrhagic stroke mortality across rural and urban areas and further investigate the potential impacts of modifiers, such as greenness, on this association.

METHODS

A multi-county time-series analysis was carried out in 19 counties of Shandong Province from 2013 to 2019. First, we employed generalized additive models (GAMs) to assess the effects of O3 on stroke mortality in each county. We performed random-effects meta-analyses to pool estimates to counties and compare differences in rural and urban areas. Furthermore, a meta-regression model was utilized to assess the moderating effects of county-level features.

RESULTS

Short-term O3 exposure was found to be associated with increased mortality for both stroke subtypes. For each 10-µg/m3 (lag0-3) rise in O3, ischaemic stroke mortality rose by 1.472% in rural areas and 1.279% in urban areas. For each 0.1-unit increase in the Enhanced Vegetation Index (EVI) per county, the ischaemic stroke mortality caused by a 10-µg/m3 rise in O3 decreased by 0.60% overall and 1.50% in urban areas.

CONCLUSIONS

Our findings add to the evidence that short-term O3 exposure increases ischaemic and haemorrhagic stroke mortality and has adverse effects in urban and rural areas. However, improving greenness levels may contribute to mitigating the detrimental effects of O3 on ischaemic stroke mortality.

In Situ and Rapid Toxicity Assessment of Air Pollution by Self-Assembly Passive Colonization Hydrogel

Air pollution is a leading environmental health risk factor, and in situ toxicity assessment is urgently needed. Bacteria-based bioassays offer cost-effective and rapid toxicity assessments. However, the application of these bioassays for air toxicity assessment has been challenging, due to the instability of bacterial survival and functionality when directly exposed to air pollutants. Here, we developed an approach employing self-assembly passive colonization hydrogel (SAPCH) for in situ air toxicity assessment. The SAPCH features a core-shell structure, enabling the quantitatively immobilization of bacteria on its shell while continuously provides nutrients from its core. An antimicrobial polyelectrolyte layer between the core and shell confines bacteria to the air-liquid interface, synchronizing bacterial survival with exposure to air pollutants. The SAPCH immobilized a battery of natural and recombinant luminescent bacteria, enabling simultaneous detection of various toxicological endpoints (cytotoxicity, genotoxicity and oxidative stress) of air pollutants within 2 h. Its sensitivity was 3-5 orders of magnitude greater than that of traditional liquid-phase toxicity testing, and successfully evaluating the toxicity of volatile organic compounds and combustion smoke. This study presents a method for in situ, rapid, and economical toxicity assessment of air pollution, making a significant contribution to future air quality monitoring and control.

Seasonal Changes in the Oxidative Potential of Urban Air Pollutants: The Influence of Emission Sources and Proton- and Ligand-Mediated Dissolution of Transition Metals

The inhalation of fine particulate matter (PM2.5) is a major contributor to adverse health effects from air pollution worldwide. An important toxicity pathway is thought to follow oxidative stress from the formation of exogenous reactive oxygen species (ROS) in the body, a proxy of which is oxidative potential (OP). As redox-active transition metals and organic species are important drivers of OP in urban environments, we investigate how seasonal changes in emission sources, aerosol chemical composition, acidity, and metal dissolution influence OP dynamics. Using a kinetic model of the lung redox chemistry, we predicted ROS (O2 •-, H2O2, •OH) formation with input parameters comprising the ambient concentrations of PM2.5, water-soluble Fe and Cu, secondary organic matter, nitrogen dioxide, and ozone across two years and two urban sites in Canada. Particulate species were the largest contributors to ROS production. Soluble Fe and Cu had their highest and lowest values in summer and winter, and changes in Fe solubility were closely linked to seasonal variations in chemical aging, the acidity of aerosol, and organic ligand levels. The results indicate three conditions that influence OP across various seasons: (a) low aerosol pH and high organic ligand levels leading to the highest OP in summer, (b) opposite trends leading to the lowest OP in winter, and (c) intermediate conditions corresponding to moderate OP in spring and fall. This study highlights how atmospheric chemical aging modifies the oxidative burden of urban air pollutants, resulting in a seasonal cycle with a potential effect on population health.

Particulate matter 2.5 accelerates aging: Exploring cellular senescence and age-related diseases

Exposure to Particulate matter 2.5 (PM2.5) accelerates aging, causing declines in tissue and organ function, and leading to diseases such as cardiovascular, neurodegenerative, and musculoskeletal disorders. PM2.5 is a major environmental pollutant and an exogenous pathogen in air pollution that is now recognized as an accelerator of human aging and a predisposing factor for several age-related diseases. In this paper, we seek to elucidate the mechanisms by which PM2.5 induces cellular senescence, such as genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, and mitochondrial dysfunction, and age-related diseases. Our goal is to increase awareness among researchers within the field of the toxicity of environmental pollutants and to advocate for personal and public health initiatives to curb their production and enhance population protection. Through these endeavors, we aim to promote longevity and health in older adults.

MiR-421 mediates PM2.5-induced endothelial dysfunction via crosstalk between bronchial epithelial and endothelial cells

OBJECTIVE

PM2.5 is closely linked to vascular endothelial injury and has emerged as a major threat to human health. Our previous research indicated that exposure to PM2.5 induced an increased release of miR-421 from the bronchial epithelium. However, the role of miR-421 in PM2.5-induced endothelial injury remains elusive.

MATERIALS AND METHODS

We utilized a subacute PM2.5-exposure model in mice in vivo and an acute injury cell model in vitro to simulate PM2.5-associated endothelial injury. We also used quantitative real-time polymerase chain reaction, western blot, enzyme-linked immunosorbent assay, and immunohistochemistry to investigate the role of miR-421 in PM2.5-induced endothelial injury.

RESULTS

Our findings reveal that inhibition of miR-421 attenuated PM2.5-induced endothelial injury and hypertension. Mechanistically, miR-421 inhibited the expression of angiotensin-converting enzyme 2 (ACE2) in human umbilical vein endothelial cells and upregulated the expression of the downstream molecule inducible nitric oxide synthase (iNOS), thereby exacerbating PM2.5-induced endothelial injury.

CONCLUSIONS

Our results indicate that PM2.5 exposure facilitates crosstalk between bronchial epithelial and endothelial cells via miR-421/ACE2/iNOS signaling pathway, mediating endothelial damage and hypertension. MiR-421 inhibition may offer a new strategy for the prevention and treatment of PM2.5-induced vascular endothelial injury.

Associations of long-term exposure to low-level PM2.5 and brain disorders in 260,922 middle-aged and older adults

Long-term exposure to high-level ambient PM2.5 was associated with increased risks of brain disorders, while the associations remain uncertain when the exposure is lower than current air quality standards in numerous countries. This study aimed to assess the effects of PM2.5 exposure on the brain system in the population with annual mean concentrations ≤15 μg/m3. We analyzed data from 260,922 participants without preexisting brain diseases at baseline in the UK Biobank. The geographical distribution of PM2.5 in 2010 was estimated by a land use regression model and linked with individual residential address. We investigated associations of ambient PM2.5 with incident neurological (dementia, Parkinson's diseases [PD], epilepsy, and migraine) and psychiatric (major depressive disorder [MDD] and anxiety disorder) diseases through Cox proportional hazard models. We further estimated the links with brain imaging phenotypes by neuroimaging analysis. Results showed that in the population with PM2.5 concentrations ≤15 μg/m3, each interquartile range (IQR, 1.28 μg/m3) increment in PM2.5 was related to incidence risks of dementia, epilepsy, migraine, MDD, and anxiety disorder with hazard ratios of 1.08 (95% confidence interval [CI]: 1.03, 1.13), 1.12 (1.05, 1.20), 1.07 (1.00, 1.13), 1.06 (1.03, 1.09), and 1.05 (1.02, 1.08), respectively. We did not observe a significant association with PD. The association with dementia was stronger among the population with poor cardiovascular health (measured by Life's Essential 8) than the counterpart (P for interaction = 0.037). Likewise, per IQR increase was associated with specific brain imaging phenotypes, including volumes of total brain (β = -0.036; 95% CI: -0.050, -0.022), white matter (-0.030; -0.046, -0.014), grey matter (-0.030; -0.042, -0.017), respectively. The findings suggest long-term exposure to ambient PM2.5 at low-level still has an adverse impact on the neuro-psychiatric systems. The brain-relevant epidemiological assessment suggests that each country should update the standard for ambient PM2.5 following the World Health Organization Air Quality Guidelines 2021.

Long-term exposure to air pollution, road traffic noise and greenness, and incidence of myocardial infarction in women

BACKGROUND

Emerging evidence shows that long-term exposure to air pollution, road traffic noise, and greenness can each be associated with cardiovascular disease, but only few studies combined these exposures. In this study, we assessed associations of multiple environmental exposures and incidence of myocardial infarction using annual time-varying predictors.

MATERIALS AND METHODS

In a population-based cohort of 20,407 women in Sweden, we estimated a five-year moving average of residential exposure to air pollution (PM2.5, PM10 and NO2), road traffic noise (Lden), and greenness (normalized difference vegetation index, NDVI in 500 m buffers), from 1998 to 2017 based on annually varying exposures and address history. We used adjusted time-varying Cox proportional hazards regressions to estimate hazard ratios (HR) and 95 % confidence intervals (95 % CI) of myocardial infarction per interquartile range (IQR). Furthermore, we investigated interactions between the exposures and explored potential vulnerable subgroups.

RESULTS

In multi-exposure models, long-term exposure to greenness was inversely associated with incidence of myocardial infarction (HR 0.89; 95 % CI 0.80, 0.99 per IQR NDVI increase). Stronger associations were observed in some subgroups, e.g. among women with low attained education and in overweight (BMI ≥ 25 kg/m2) compared to their counterparts. For air pollution, we observed a tendency of an increased risk of myocardial infarction in relation to PM2.5 (HR 1.07; 95 % CI 0.93, 1.23) and the association appeared stronger in women with low attained education (HR 1.30; 95 % CI 1.06, 1.58). No associations were observed for PM10, NO2 or road traffic noise. Furthermore, there were no clear interaction patterns between the exposures.

CONCLUSION

Over a 20-year follow-up period, in multi-exposure models, we found an inverse association between residential greenness and risk of myocardial infarction among women. Furthermore, we observed an increased risk of myocardial infarction in relation to PM2.5 among women with low attained education. Road traffic noise was not associated with myocardial infarction.

Association between synoptic types in Beijing and acute myocardial infarction hospitalizations: A comprehensive analysis of environmental factors

BACKGROUND

Environmental factors like air pollution and temperature can trigger acute myocardial infarction (AMI). However, the link between large-scale weather patterns (synoptic types) and AMI admissions has not been extensively studied. This research aimed to identify the different synoptic air types in Beijing and investigate their association with AMI occurrences.

METHODS

We analyzed data from Beijing between 2013 and 2019, encompassing 2556 days and 149,632 AMI cases. Using principal component analysis and hierarchical clustering, classification into distinct synoptic types was conducted based on weather and pollution measurements. To assess the impact of each type on AMI risk over 14 days, we employed a distributed lag non-linear model (DLNM), with the reference being the lowest risk type (Type 2).

RESULTS

Four synoptic types were identified: Type 1 with warm, humid weather; Type 2 with warm temperatures, low humidity, and long sunshine duration; Type 3 with cold weather and heavy air pollution; and Type 4 with cold temperatures, dryness, and high wind speed. Type 4 exhibited the greatest cumulative relative risk (CRR) of 1.241 (95%CI: 1.150, 1.339) over 14 days. Significant effects of Types 1, 3, and 4 on AMI events were observed at varying lags: 4-12 days for Type 1, 1-6 days for Type 3, and 1-11 days for Type 4. Females were more susceptible to Types 1 and 3, while individuals younger than 65 years old showed increased vulnerability to Types 3 and 4.

CONCLUSION

Among the four synoptic types identified in Beijing from 2013 to 2019, Type 4 (cold, dry, and windy) presented the highest risk for AMI hospitalizations. This risk was particularly pronounced for males and people under 65. Our findings collectively highlight the need for improved methods to identify synoptic types. Additionally, developing a warning system based on these synoptic conditions could be crucial for prevention.

Association between PM2.5 constituents and cardiometabolic risk factors: Exploring individual and combined effects, and mediating inflammation

BACKGROUND

The individual and combined effects of PM2.5 constituents on cardiometabolic risk factors are sparsely investigated. Besides, the key cardiometabolic risk factor that PM2.5 constituents targeted and the biological mechanisms remain unclear.

METHOD

A multistage, stratified cluster sampling survey was conducted in two typically air-polluted Chinese cities. The PM2.5 and its constituents including sulfate, nitrate, ammonium, organic matter, and black carbon were predicted using a machine learning model. Twenty biomarkers in three category were simultaneously adopted as cardiometabolic risk factors. We explored the individual and mixture association of long-term PM2.5 constituents with these markers using generalized additive model and quantile-based g-computation, respectively. To minimize potential confounding effects, we accounted for covariates including demographic, lifestyle, meteorological, temporal trends, and disease-related information. We further used ROC curve and mediation analysis to identify the key subclinical indicators and explore whether inflammatory mediators mediate such association, respectively.

RESULT

PM2.5 constituents was positively correlated with HOMA-B, TC, TG, LDL-C and LCI, and negatively correlated with PP and RC. Further, PM2.5 constituent mixture was positive associated with DBP, MAP, HbA1c, HOMA-B, AC, CRI-1 and CRI-2, and negative associated with PP and HDL-C. The ROC analysis further reveals that multiple cardiometabolic risk factors can collectively discriminate exposure to PM2.5 constituents (AUC>0.9), among which PP and CRI-2 as individual indicators exhibit better identifiable performance for nitrate and ammonium (AUC>0.75). We also found that multiple blood lipid indicators may be affected by PM2.5 and its constituents, possibly mediated through complement C3 or hsCRP.

CONCLUSION

Our study suggested associations of individual and combined PM2.5 constituents exposure with cardiometabolic risk factors. PP and CRI-2 were the targeted markers of long-term exposure to nitrate and ammonium. Inflammation may serve as a mediating factor between PM2.5 constituents and dyslipidemia, which enhance current understanding of potential pathways for PM2.5-induced preclinical cardiovascular responses.

Bibliometric analysis of global research on air pollution and cardiovascular diseases: 2012-2022

Background

The relationship between air pollution and cardiovascular diseases (CVDs) has garnered significant interest among researchers globally. This study employed bibliometric analysis to provide an overview of current research on the association between air pollution and CVDs, offering a comprehensive analysis of global research trends in this area.

Methods

An exhaustive scrutiny of literature pertaining to the nexus between air pollution and CVDs from 2012 to 2022 was conducted through rigorous screening of the Web of Science Core Collection (WoSCC). Publications were exclusively considered in English. Subsequently, sophisticated analytical tools including CiteSpace 6.2.4R, Vosviewer 1.6.19, HistCite 2.1, Python 3.7.5, Microsoft Charticulator, and Bibliometrix Online Analysis Platform were deployed to delineate research trends in this domain.

Results

The analysis of the dataset, comprising 1710 documents, unveiled a consistent escalation in scientific publications, peaking in 2022 with a total of 248 publications. Moreover, Environmental Science and Toxicology stood out as the predominant categories. Examination of keyword frequency highlighted the terms 'air pollution', 'cardiovascular disease', and 'particulate matter' as the most prevalent. Notably, the most prolific entities, in terms of authors, journals, organizations, and countries, were identified as Robert D. Brook, Environmental Health Perspectives, Harvard University, and the United States, respectively.

Conclusion

The findings presented a notable increase in high-quality publications on this topic over the past 11 years, suggesting a positive outlook for future research. The study concluded with an examination of three key themes in research trends related to air pollution and CVDs: the initial physiological response to pollutant exposure, the pathways through which pollutants are transmitted, and the subsequent effects on target organs. Additionally, various air pollutants, such as particulate matter, nitric dioxide, and ozone, could contribute to multiple CVDs, including coronary heart disease, hypertension, and heart failure. Although some hypotheses have been put forward, the mechanisms of air pollution-related CVDs still need to be explored in the future.

Greenness mitigate cause-specific mortality associated with air pollutants in ischemic and hemorrhagic stroke patients: An ecological health cohort study

BACKGROUND

Air pollution is one of the most serious environmental risks to mortality of stroke. However, there exists a noteworthy knowledge gap concerning the different stroke subtypes, causes of death, the susceptibility of stroke patient, and the role of greenness in this context.

METHODS

We analyzed data from an ecological health cohort, which included 334,261 patients aged ≥40 years with stroke (comprising 288,490 ischemic stroke and 45,771 hemorrhagic stroke) during the period 2013-2019. We used Cox proportional hazards models with time-varying exposure to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) to assess the associations of annual average fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) with both all-cause and cause-specific mortality. Additionally, we conducted analyses to examine the effect modification by greenness and identify potential susceptibility factors through subgroup analyses.

RESULT

In multivariable-adjusted models, long-term exposure to PM2.5 and NO2 was associated with increased risk of all-cause mortality (HR: 1.038, 95% CI: 1.029-1.047 for PM2.5; HR: 1.055, 95% CI: 1.026-1.085 for NO2, per 10 μg/m3, for ischemic stroke patients; similar for hemorrhagic stroke patients). Gradually increasing effect sizes were shown for CVD mortality and stroke mortality. The HRs of mortality were slightly weaker with high versus low vegetation exposure. Cumulative exposures increased the HRs of pollutant-related mortality, and greater greenness decreased this risk. Two subtypes of stroke patients exhibited diverse patterns of benefit.

CONCLUSION

Increasing residential greenness attenuates the increased risk of mortality with different patterns due to chronic air pollutants for ischemic and hemorrhagic stroke, offering valuable insights for precise tertiary stroke prevention strategies.

Environmental pollutants exposure-derived extracellular vesicles: crucial players in respiratory disorders

BACKGROUND

Individual exposure to environmental pollutants, as one of the most influential drivers of respiratory disorders, has received considerable attention due to its preventability and controllability. Considering that the extracellular vesicle (EV) was an emerging intercellular communication medium, recent studies have highlighted the crucial role of environmental pollutants derived EVs (EPE-EVs) in respiratory disorders.

METHODS

PubMed and Web of Science were searched from January 2018 to December 2023 for publications with key words of environmental pollutants, respiratory disorders and EVs.

RESULTS

Environmental pollutants could disrupt airway intercellular communication by indirectly stimulating airway barrier cells to secrete endogenous EVs, or directly transmitting exogenous EVs, mainly by biological pollutants. Mechanistically, EPE-EVs transferred specific contents to modulate biological functions of recipient cells, to induce respiratory inflammation and impair tissue and immune function, which consequently contributed to the development of respiratory diseases, such as asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, pulmonary hypertension, lung cancer and infectious lung diseases. Clinically, EVs could emerged as promising biomarkers and biological agents for respiratory diseases attributed by their specificity, convenience, sensibility and stability.

CONCLUSIONS

Further studies of EPE-EVs are helpful to understand the aetiology and pathology of respiratory diseases, and facilitate the precision respiratory medicine in risk screening, early diagnosis, clinical management and biotherapy.

Environmentally Not So Friendly: Global Warming, Air Pollution, and Wildfires: JACC Focus Seminar, Part 1

Environmental stresses are increasingly recognized as significant risk factors for adverse health outcomes. In particular, various forms of pollution and climate change are playing a growing role in promoting noncommunicable diseases, especially cardiovascular disease. Given recent trends, global warming and air pollution are now associated with substantial cardiovascular morbidity and mortality. As a vicious cycle, global warming increases the occurrence, size, and severity of wildfires, which are significant sources of airborne particulate matter. Exposure to wildfire smoke is associated with cardiovascular disease, and these effects are underpinned by mechanisms that include oxidative stress, inflammation, impaired cardiac function, and proatherosclerotic effects in the circulation. In the first part of a 2-part series on pollution and cardiovascular disease, this review provides an overview of the impact of global warming and air pollution, and because of recent events and emerging trends specific attention is paid to air pollution caused by wildfires.

Risk Factors and Preventive Measures for Cardiovascular Diseases

Background: Cardiovascular diseases are the most frequent cause of death worldwide. The aim of this study was to identify and demonstrate correlations between mortality data and etiological factors in EU countries. The relationships presented could thus provide a better understanding of etiological factors and possible points for interventions to prevent cardiovascular diseases. The focus was on the following diseases: hypertensive heart disease, atrial flutter/atrial fibrillation, myocardial infarction, and ischemic heart disease, as well as heart failure. Methods: The data in this study come from WHO databases. Connections between the mortality rates and the possible influencing factors were analyzed. The significant factors from the correlation analysis were simultaneously evaluated using a stepwise multiple regression analysis. Results: Analysis of hypertensive heart disease in women reveals the following factors to be significant: drug expenses, health expenses on gross domestic product, and smoking. For men, population density, first admission to a drug treatment center, and drug expenses per person emerged as important factors. Admission to drug treatment centers and length of hospitalization were significant factors for atrial fibrillation and flutter. Fine dust pollution was the most important factor in heart failure. The most important influencing factor for myocardial infarction and ischemic heart disease is nitrogen dioxide concentration. For women, the second highest value is health expenses, followed by the number of outpatient contacts per year. For men, outpatient contacts are in second place. Conclusions: Prevention measures must be taken by the government. The extent to which population density has an influence on cardiovascular diseases should be examined in more detail. In order to reduce the number of initial admissions to drug treatment centers, behavioral prevention related to drug use could be improved.

Short-term effects of nitrogen dioxide on inpatient acute myocardial infarction in Lanzhou, China

Nitrogen dioxide (NO2) represents a deleterious effect on acute myocardial infarction (AMI), but few relevant studies have been conducted in China. We aim to evaluate the acute effects of NO2 exposure on hospitalization for AMI in Lanzhou, China. In this study, we applied a distributional lag nonlinear model (DLNM) to assess the association between NO2 exposure and AMI hospitalization. We explored the sensitivity of various groups through stratified analysis by gender, age, and season. The daily average concentration of NO2 is 47.50 ± 17.38 µg/m3. We observed a significant exposure-response relationship between NO2 concentration and AMI hospitalization. The single pollutant model analysis shows that NO2 is positively correlated with AMI hospitalization at lag1, lag01, lag02, and lag03. The greatest lag effect estimate occurs at lag01, where a 10 µg/m3 increase in NO2 concentrations is significantly associated with a relative risk (RR) of hospitalization due to AMI of 1.027 [95% confidence interval (CI): 1.013, 1.042]. The results of the stratified analysis by gender, age, and season indicate that males, those aged ≥65 years, and the cold season are more sensitive to the deleterious effects caused by NO2 exposure. Short-term exposure to NO2 can enhance the risk of AMI hospitalization in urban Lanzhou.Implications: Exposure to particulate matter can lead to an increased incidence of AMI. Our study once again shows that NO2 exposure increases the risk of AMI hospital admission. AMI is a common and expensive fatal condition. Reducing NO2 exposure will benefit cardiovascular health and save on healthcare costs.

Exploring the Effects of Local Air Pollution on Popliteal Artery Aneurysms

Objectives: A growing body of evidence highlights the effects of air pollution on chronic and acute cardiovascular diseases, such as associations between PM10 and several cardiovascular events. However, evidence of the impact of fine air pollutants on the development and progression of peripheral arterial aneurysms is not available. Methods: Data were obtained from the multicenter PAA outcome registry POPART and the German Environment Agency. Means of the mean daily concentration of PM10, PM2.5, NO2, and O3 concentrations were calculated for 2, 10, and 3650 days prior to surgery for each patient. Additionally, weighted ten-year averages were analyzed. Correlation was assessed by calculating Pearson correlation coefficients, and regression analyses were conducted as multiple linear or multiple logistic regression, depending on the dependent variable. Results: For 1193 patients from the POPART registry, paired air pollution data were available. Most patients were male (95.6%) and received open surgical repair (89.9%). On a regional level, the arithmetic means of the daily means of PM10 between 2000 and 2022 were neither associated with average diameters nor runoff vessels. Negative correlations for mean PAA diameter and mean NO2, as well as a positive correlation with mean O3, were found; however, they were not statistically significant. On patient level, no evidence for an association of mean PM10 exposure over ten years prior to inclusion in the registry and PAA diameter or the number of runoff vessels was found. Weighted PM10, NO2, and O3 exposure over ten years also did not result in significant associations with aneurysm diameter or runoff vessels. Short-term air pollutant concentrations were not associated with symptomatic PAAs or with perioperative complications. Conclusions: We found no indication that long-term air pollutant concentrations are associated with PAA size or severity, neither on a regional nor individual level. Additionally, short-term air pollution showed no association with clinical presentation or treatment outcomes.

Burden of Stroke Attributable to Nonoptimal Temperature in 204 Countries and Territories: A Population-Based Study, 1990-2019

BACKGROUND AND OBJECTIVES

Stroke attributable to nonoptimal temperature needs more attention with dramatic climate change. The aim of this study was to estimate the global burden and distribution characteristics of the burden.

METHODS

In this ecological study, we collected data from the Climate Research Unit Gridded Time Series, the World Bank databases, and the Global Burden of Diseases study to estimate the distribution of burden. We used the joinpoint model, decomposition analysis, age-period-cohort model, panel data analysis, and health inequality analysis to assess the different types of stroke burden attributable to different climatic conditions.

RESULTS

The burden of stroke attributable to nonoptimal temperature continued to grow, and aging was a key factor in this increase. In 2019, 521,031 (95% uncertainty interval [UI] 402,433-663,996) deaths and 9,423,649 (95% UI 7,207,660-12,055,172) disability-adjusted life years [DALYs] attributable to stroke due to nonoptimal temperature were recorded globally. Globally, men (age-standardized mortality rate [ASMR] 7.70, 95% UI 5.80-9.73; age-standardized DALY rate [ASDR] 139.69, 95% UI 102.96-178.54 in 2019) had a heavier burden than women (ASMR 5.89, 95% UI 4.50-7.60; ASDR 96.02, 95% UI 72.62-123.85 in 2019). Central Asia (ASMR 18.12, 95% UI 13.40-24.53; ASDR 327.35, 95% UI 240.24-440.61 in 2019) had the heaviest burden at the regional level. In the national level, North Macedonia (ASMR 32.97, 95% UI 20.57-47.44 in 2019) and Mongolia (ASDR 568.54, 95% UI 242.03-1,031.14 in 2019) had the highest ASMR/ASDR, respectively. Low temperature currently contributes to the main burden (deaths 474,002, 95% UI 355,077-606,537; DALYs 8,357,198, 95% UI 6,186,217-10,801,911 attributable to low temperature vs deaths 48,030, 95% UI 5,630-104,370; DALYs 1,089,329, 95% UI 112,690-2,375,345 attributable to high temperature in 2019). However, the burden due to high temperature has increased rapidly, especially among people aged older than 10 years, and was disproportionately concentrated in low sociodemographic index (SDI) regions such as Africa. In addition, the rapid increase in the stroke burden due to high temperature in Central Asia also requires special attention.

DISCUSSION

This is the first study to assess the global stroke burden attributed to nonoptimal temperature. The dramatic increase in the burden due to high temperature requires special attention, especially in low-SDI countries.

Personal Strategies to Reduce the Cardiovascular Impacts of Environmental Exposures

Ubiquitous environmental exposures increase cardiovascular disease risk via diverse mechanisms. This review examines personal strategies to minimize this risk. With regard to fine particulate air pollution exposure, evidence exists to recommend the use of portable air cleaners and avoidance of outdoor activity during periods of poor air quality. Other evidence may support physical activity, dietary modification, omega-3 fatty acid supplementation, and indoor and in-vehicle air conditioning as viable strategies to minimize adverse health effects. There is currently insufficient data to recommend specific personal approaches to reduce the adverse cardiovascular effects of noise pollution. Public health advisories for periods of extreme heat or cold should be observed, with limited evidence supporting a warm ambient home temperature and physical activity as strategies to limit the cardiovascular harms of temperature extremes. Perfluoroalkyl and polyfluoroalkyl substance exposure can be reduced by avoiding contact with perfluoroalkyl and polyfluoroalkyl substance-containing materials; blood or plasma donation and cholestyramine may reduce total body stores of perfluoroalkyl and polyfluoroalkyl substances. However, the cardiovascular impact of these interventions has not been examined. Limited utilization of pesticides and safe handling during use should be encouraged. Finally, vasculotoxic metal exposure can be decreased by using portable air cleaners, home water filtration, and awareness of potential contaminants in ground spices. Chelation therapy reduces physiological stores of vasculotoxic metals and may be effective for the secondary prevention of cardiovascular disease.

Impact of comprehensive air pollution control policies on six criteria air pollutants and acute myocardial infarction morbidity, Weifang, China: A quasi-experimental study

Comprehensive air pollution control policies may reduce pollutant emissions. However, the impact on disease morbidity of the change for the concentration of air pollutants following the policies has been insufficiently studied. We aim to assess the impact of comprehensive air pollution control policies on the levels of six criteria air pollutants and acute myocardial infarction (AMI) morbidity in Weifang, China. This study performed an interrupted time series analysis. The linear model with spline terms and generalized additive quasi-Poisson model were used to estimate the immediate change from 2016 to 2019 in the daily concentration of six air pollutants (PM2.5, PM10, SO2, NO2, O3, and, CO) and AMI incident cases (Age ≥35) associated with the implementation of air pollution control policies in Weifang, respectively. After the implementation of air pollution control policies, air quality in Weifang had been improved. Specifically, the daily concentrations of PM2.5, PM10, SO2, and, CO immediately decreased by 27.9 % (95 % CI: 6.6 % to 44.3 %), 32.9 % (95 % CI: 17.5 % to 45.5 %), 14.6 % (95 % CI: 0.4 % to 26.8 %), and 33.9 % (95 % CI: 22.0 % to 44.0 %), respectively. In addition, the policies implementation was also associate with the immediate decline in the AMI morbidity (-6.5 %, 95 % CI: -10.4 % to -2.3 %). And subgroup analyses indicate that the health effects of the policy intervention were only observed in female (-9.4 %, 95 % CI: -14.4 % to -4.2 %) and those aged ≥65 years (-10.5 %, 95 % CI: -14.6 % to -6.2 %). During the final 20 months of the study period, the policy intervention was estimated to prevent 1603 (95 % CI: 574 to 2587) cases of incident AMI in Weifang. Our results provide strong rationale that the policy intervention significantly reduced ambient pollutant concentrations and AMI morbidity, which highlighted the importance for a comprehensive and rigorous air pollution control policy in regions with severe air pollution.

Exercise-Mediated Protection against Air Pollution-Induced Immune Damage: Mechanisms, Challenges, and Future Directions

Air pollution, a serious risk factor for human health, can lead to immune damage and various diseases. Long-term exposure to air pollutants can trigger oxidative stress and inflammatory responses (the main sources of immune impairment) in the body. Exercise has been shown to modulate anti-inflammatory and antioxidant statuses, enhance immune cell activity, as well as protect against immune damage caused by air pollution. However, the underlying mechanisms involved in the protective effects of exercise on pollutant-induced damage and the safe threshold for exercise in polluted environments remain elusive. In contrast to the extensive research on the pathogenesis of air pollution and the preventive role of exercise in enhancing fitness, investigations into exercise resistance to injury caused by air pollution are still in their infancy. In this review, we analyze evidence from humans, animals, and cell experiments on the combined effects of exercise and air pollution on immune health outcomes, with an emphasis on oxidative stress, inflammatory responses, and immune cells. We also propose possible mechanisms and directions for future research on exercise resistance to pollutant-induced damage in the body. Furthermore, we suggest strengthening epidemiological studies at different population levels and investigations on immune cells to guide how to determine the safety thresholds for exercise in polluted environments.

Green space and its types can attenuate the associations of PM2.5 and its components with prediabetes and diabetes-- a multicenter cross-sectional study from eastern China

BACKGROUND

The effect of fine particulate matter (PM2.5) components on prediabetes and diabetes is of concern, but the evidence is limited and the specific role of different green space types remains unclear. This study aims to investigate the relationship of PM2.5 and its components with prediabetes and diabetes as well as the potential health benefits of different types and combinations of green spaces.

METHODS

A multicenter cross-sectional study was conducted in eastern China by using a multi-stage random sampling method. Health screening and questionnaires for 98,091 participants were performed during 2017-2020. PM2.5 and its five components were estimated by the inverse distance weighted method, and green space was reflected by the Normalized Difference Vegetation Index (NDVI), percentages of tree or grass cover. Multivariate logistic regression and quantile g-computing were used to explore the associations of PM2.5 and five components with prediabetes and diabetes and to elucidate the potential moderating role of green space and corresponding type combinations in these associations.

RESULTS

Each interquartile range (IQR) increment of PM2.5 was associated with both prediabetes (odds ratio [OR]: 1.15, 95%CI [confidence interval]: 1.10-1.20) and diabetes (OR: 1.18, 95% CI: 1.11-1.25), respectively. All five components of PM2.5 were related to prediabetes and diabetes. The ORs of PM2.5 on diabetes were 1.49 (1.35-1.63) in the low tree group and 0.90 (0.82-0.98) in the high tree group, respectively. In the high tree-high grass group, the harmful impacts of PM2.5 and five components were significantly lower than in the other groups.

CONCLUSION

Our study suggested that PM2.5 and its components were associated with the increased risk of prediabetes and diabetes, which could be diminished by green space. Furthermore, the coexistence of high levels of tree and grass cover provided greater benefits. These findings had critical implications for diabetes prevention and green space-based planning for healthy city.

Association of Long-Term Exposure to Ambient Air Pollution With the Risk of Acute Primary Angle Closure

Purpose

The purpose of this study was to investigate the association between long-term exposure to ambient air pollutants and the risk of acute primary angle closure (APAC).

Methods

Two hundred eighty-one (281) patients with APAC and 730 age- and sex-matched controls hospitalized between January 2017 and December 2019 were enrolled in this retrospective case-control study. Residential exposure to ambient air pollutants, including fine particulate matter (PM2.5), inhalable particulate (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone were estimated by satellite-models or ground measurement. Multivariate regression analyses explored the association between annual air pollutants exposure and the risk of APAC.

Results

Of the 1011 participants (31.1% were male subjects), the average age was 64.0 years. Long-term exposure to PM2.5, PM10, and SO2 were significantly associated with an increased risk of APAC. The adjusted odds ratios (aORs) for each interquartile range (IQR) increment of PM2.5, PM10, and SO2 were 1.28 (95% confidence interval [CI] = 1.06-1.57), 1.26 (95% CI = 1.06-1.50), and 1.30 (95% CI = 1.04-1.62) separately, after controlling for confounders. Robust associations were observed for a longer lag 2-year exposure.

Conclusions

Long-term exposure to PM2.5, PM10, and SO2 was associated with an increased risk of APAC in a Chinese population. Our findings provide epidemiological implications on the adverse effects of air pollution on ocular diseases.

Translational Relevance

Long-term exposure to ambient air pollutants increased the risk of APAC.

Airborne magnetite nanoparticles induced early vascular pathologies by disrupting lipid metabolism under high-fat dietary patterns

Magnetite nanoparticles (MNPs) have been extensively detected in the atmospheric environment and implicated as a prominent threat to atherosclerosis, a chronic vascular inflammatory disease. Due to globalization and economic development, the dramatic shift in diet from traditional to high-fat dietary patterns aggravated atherosclerosis progression induced by environmental factors. However, limited knowledge is available regarding vascular risks and underlying mechanisms of airborne MNPs in high-risk populations with high-fat dietary habits. Herein, we demonstrated that MNPs exerted a proatherogenic effect under high-fat dietary patterns, leading to aortic wall thickening, elastic fiber disorganization, macrophage infiltration, and local inflammation. Based on the correlation analysis between MNPs and PM group, we identified that MNPs might be a key PM component in atherogenic toxicity. MNPs exposure disturbed the dynamic process of lipid metabolism, manifested as aortic lipid accumulation, dyslipidemia, and hepatic lipid metabolism disorder, which was modulated by the JAK-STAT pathway. Overall, these findings provide new insight into understanding the cardiovascular risks and mechanisms of MNPs among high-risk populations.

Air pollution exposure and cardiometabolic risk

The Global Burden of Disease assessment estimates that 20% of global type 2 diabetes cases are related to chronic exposure to particulate matter (PM) with a diameter of 2·5 μm or less (PM2·5). With 99% of the global population residing in areas where air pollution levels are above current WHO air quality guidelines, and increasing concern in regard to the common drivers of air pollution and climate change, there is a compelling need to understand the connection between air pollution and cardiometabolic disease, and pathways to address this preventable risk factor. This Review provides an up to date summary of the epidemiological evidence and mechanistic underpinnings linking air pollution with cardiometabolic risk. We also outline approaches to improve awareness, and discuss personal-level, community, governmental, and policy interventions to help mitigate the growing global public health risk of air pollution exposure.

[Air pollution, noise and hypertension : Partners in crime]

Air pollution and traffic noise are two important environmental risk factors that endanger health in urban societies and often act together as "partners in crime". Although air pollution and noise often co-occur in urban environments, they have typically been studied separately, with numerous studies documenting consistent effects of individual exposure on blood pressure. In the following review article, we examine the epidemiology of air pollution and noise, especially regarding the cardiovascular risk factor arterial hypertension and the underlying pathophysiology. Both environmental stressors have been shown to lead to endothelial dysfunction, oxidative stress, pronounced vascular inflammation, disruption of circadian rhythms and activation of the autonomic nervous system, all of which promote the development of hypertension and cardiovascular diseases. From a societal and political perspective, there is an urgent need to point out the potential dangers of air pollution and traffic noise in the American Heart Association (AHA)/American College of Cardiology (ACC) prevention guidelines and the European Society of Cardiology (ESC) guidelines on prevention. Therefore, an essential goal for the future is to raise awareness of environmental risk factors as important and, in particular, preventable risk factors for cardiovascular diseases.

Heterogeneous (gas-solid) chemistry of atmospheric Cr: A case study of Astana, Kazakhstan

Hexavalent chromium (Cr(VI)) is a known carcinogen derived from both anthropogenic and natural sources. This work reports the size-segregated concentrations of total Cr(VI) in particulate matter (PM) in Astana, the capital of Kazakhstan, and provides new insights into the gas-solid reactions of atmospheric Cr. A study of total Cr(VI) in the particulate matter, via a microwave-assisted digestion technique, was conducted using a 5-stage Sioutas Cascade impactor that captures airborne particles in size ranges: >2.5 μm, 1.0-2.5 μm, 0.50-1.0 μm, 0.25-0.50 μm, and <0.25 μm. The total Cr(VI) concentration in the size fraction <0.25 μm was the highest with a maximum value of 9.7 ng/m3. This high concentration may pose a greater risk because smaller airborne particles can penetrate deeper into the lower respiratory tract of the lungs. Total suspended particles Cr(VI) exceeded the 8.0 ng/m3 Reference Concentration (RfC) by 22 times. The overall total Cr(VI) concentration in summer was significantly higher than in fall (p < 0.05), which could be due to factors, including higher temperatures, ozone, and NO2 concentrations in summer and a higher VOC concentration in fall. The results indicate that the interaction between Cr(III) and Cr(VI) through gas-solid reaction can control the speciation of atmospheric Cr.

Short-term air pollution exposure and mechanisms of plaque instability in acute coronary syndromes: An optical coherence tomography study

BACKGROUND AND AIMS

Air pollution is emerging as an important risk factor for acute coronary syndrome (ACS). In this study, we investigated the association between short-term air pollution exposure and mechanisms of coronary plaque instability evaluated by optical coherence tomography (OCT) imaging in ACS patients.

METHODS

Patients with ACS undergoing OCT imaging were retrospectively selected. Mechanism of culprit lesion instability was classified as plaque rupture (PR) or intact fibrous cap (IFC) by OCT. Based on each case's home address, the mean daily exposures to several pollutants, including particulate matter 2.5 (PM2.5), on the same day of ACS and in the immediate days (up to 6 days) prior to the index ACS, were collected.

RESULTS

139 ACS patients were included [69 (49.6%) had PR and 70 (50.4%) IFC]. Patients with PR, compared to those with IFC, had higher PM2.5 exposure levels on the same day of ACS, without differences in the immediate 6 days before index ACS. At multivariate analysis, PM2.5 exposure on the same day of ACS was the only independent predictor of PR [OR = 1.912 per SD (8.6 μg/m3), CI95 % (1.087-3.364), p = 0.025]. Patients with PR presented a steady increase in PM2.5 daily exposure levels in the days preceding the occurrence of ACS, with a peak the day of ACS (p for trend = 0.042) CONCLUSIONS: This study demonstrates for the first time that a higher short-term PM2.5 exposure, on the same day of ACS, is associated with an increased risk of PR as a pathobiological mechanism of coronary plaque instability.

Causal effect of air pollution on the risk of cardiovascular and metabolic diseases and potential mediation by gut microbiota

BACKGROUND

Epidemiological studies have explored the relationship between air pollution and cardiovascular and metabolic diseases (CVMDs). Accumulating evidence has indicated that gut microbiota deeply affects the risk of CVMDs. However, the findings are controversial and the causality remains uncertain. To evaluate whether there is the causal association of four air pollutants with 19 CVMDs and the potential effect of gut microbiota on these relationships.

METHODS

Genetic instruments for particulate matter (PM) with aerodynamic diameter < 2.5 μm (PM2.5), <10 μm (PM10), PM2.5 absorbance, nitrogen oxides (NOx) and 211 gut microbiomes were screened. Univariable Mendelian randomization (UVMR) was used to estimate the causal effect of air pollutants on CVMDs in multiple MR methods. Additionally, to account for the phenotypic correlation among pollutant, the adjusted model was constructed using multivariable Mendelian randomization (MVMR) analysis to strength the reliability of the predicted associations. Finally, gut microbiome was assessed for the mediated effect on the associations of identified pollutants with CVMDs.

RESULTS

Causal relationships between NOx and angina, heart failure and hypercholesterolemia were observed in UVMR. After adjustment for air pollutants in MVMR models, the genetic correlations between PM2.5 and hypertension, type 2 diabetes mellitus (T2DM) and obesity remained significant and robust. In addition, genus-ruminococcaceae-UCG003 mediated 7.8 % of PM2.5-effect on T2DM.

CONCLUSIONS

This study firstly provided the genetic evidence linking air pollution to CVMDs and gut microbiota may mediate the association of PM2.5 with T2DM. Our findings highlight the significance of air quality in CVMDs risks and suggest the potential of modulating intestinal microbiota as novel therapeutic targets between air pollution and CVMDs.

Exposome in ischaemic heart disease: beyond traditional risk factors

Ischaemic heart disease represents the leading cause of morbidity and mortality, typically induced by the detrimental effects of risk factors on the cardiovascular system. Although preventive interventions tackling conventional risk factors have helped to reduce the incidence of ischaemic heart disease, it remains a major cause of death worldwide. Thus, attention is now shifting to non-traditional risk factors in the built, natural, and social environments that collectively contribute substantially to the disease burden and perpetuate residual risk. Of importance, these complex factors interact non-linearly and in unpredictable ways to often enhance the detrimental effects attributable to a single or collection of these factors. For this reason, a new paradigm called the 'exposome' has recently been introduced by epidemiologists in order to define the totality of exposure to these new risk factors. The purpose of this review is to outline how these emerging risk factors may interact and contribute to the occurrence of ischaemic heart disease, with a particular attention on the impact of long-term exposure to different environmental pollutants, socioeconomic and psychological factors, along with infectious diseases such as influenza and COVID-19. Moreover, potential mitigation strategies for both individuals and communities will be discussed.

Ambient fine particulate matter chemical composition associated with in-hospital case fatality, hospital expenses, and length of hospital stay among patients with heart failure in China

*Joint senior authorship.

BACKGROUND

Previous studies have observed the adverse effects of ambient fine particulate matter pollution (PM2.5) on heart failure (HF). However, evidence regarding the impacts of specific PM2.5 components remains scarce.

METHODS

We included 58 129 patients hospitalised for HF between 2013 and 2017 in 11 cities of Shanxi, China from inpatient discharge database. We evaluated exposure to PM2.5 and its components ((sulphate (SO42-), nitrate (NO3-), ammonium (NH4+), organic matter (OM) and black carbon (BC)), along with meteorological factors using bilinear interpolation at each patients' residential address. We used multivariable logistic and linear regression models to assess the associations of these components with in-hospital case fatality, hospital expenses, and length of hospital stay.

RESULTS

Increase equivalents to the interquartile range (IQR) in OM (odds ratio (OR) = 1.13; 95% confidence interval (CI) = 1.02, 1.26) and BC (OR = 1.14; 95% CI = 1.02, 1.26) were linked to in-hospital case fatality. Per IQR increments in PM2.5, SO42-, NO3-, OM, and BC were associated with cost increases of 420.62 (95% CI = 285.75, 555.49), 221.83 (95% CI = 96.95, 346.71), 214.93 (95% CI = 68.66, 361.21), 300.06 (95% CI = 176.96, 423.16), and 303.09 (95% CI = 180.76, 425.42) CNY. Increases of 1 IQR in PM2.5, SO42-, OM, and BC were associated with increases in length of hospital stay of 0.10 (95% CI = 0.02, 0.19), 0.09 (95% CI = 0.02, 0.17), 0.10 (95% CI = 0.03, 0.17), and 0.16 (95% CI = 0.08, 0.23) days.

CONCLUSIONS

Our findings suggest that ambient SO42-, OM, and BC might be significant risk factors for HF, emphasising the importance of formulating customised guidelines for the chemical constituents of PM and controlling the emissions of the most dangerous components.

Association between short-term exposure to ambient air pollution and upper respiratory tract infection in Kunshan

The health effects of air pollution have become a major public health problem. Studies on the relationship between short-term exposure to air pollutants and upper respiratory tract infection (URTI) related clinic visits and expenditures were scarce. From January 1, 2019, to December 31, 2021, we included all the URTI cases that turned to 11 public hospitals in Kunshan, and summarized individual medical cost. Daily meteorological factors and 24-h mean concentrations of four common air pollutants, including particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5) and 10 μm (PM10), sulfur dioxide (SO2), and nitrogen dioxide (NO2), were consecutively recorded. Generalized additive regression model was adopted to quantify the associations between each air pollutant and the daily clinic visits of URTI cases. We further calculated attributable number (AN) and attributable fraction, and performed sensitivity analysis by gender, age, and season. A total of 934,180 cases were retrieved during the study period. PM2.5, PM10, SO2, and NO2 showed significant associations with hospital visits and expenditures due to URTI. Relative risks for them were 1.065 (95% confidence interval [CI] 1.055, 1.076), 1.045 (95% CI 1.037, 1.052), 1.098 (95% CI 1.038, 1.163), and 1.098 (95% CI 1.085, 1.111) on lag 0-5 days, respectively. Thirty-one thousand four hundred fifty-five (95% CI 27,457, 35,436) cases could be ascribed to increased NO2 and accounted for 3.37% (95% CI 2.94%, 3.79%) of all clinic visits. Sensitivity analyses indicated that the effects of air pollution were generally consistent for male and female. PM2.5, PM10, and NO2 had stronger associations among people aged ≤ 18 years, followed by those aged 19-64 years and ≥ 65 years. The association strengths of air pollution varied seasonally. Short-term exposure to ambient air pollutants had significant associations with clinic visits and expenditures owing to URTI. Children and adolescents appeared to be more susceptible to adverse health effects of air pollution. NO2 may be a priority when formulating pollution control measures.

Long-term exposure to air pollution and risk of insulin resistance: A systematic review and meta-analysis

OBJECTIVE

The effects of air pollution on metabolism have become a popular research topic, and a large number of studies had confirmed that air pollution exposure could induce insulin resistance (IR) to varying degrees, but the results were inconsistent, especially for the long-term exposures. The aim of the current study was to further investigate the potential effects of air pollution on IR.

METHODS

A systematic review and meta-analysis of four electronic databases, including PubMed, Embase, Web of Science and Cochrane were conducted, searching for relevant studies published before June 10, 2023, in order to explore the potential relationships between long-term exposure to air pollution and IR. A total of 10 studies were included for data analysis, including seven cohort studies and three cross-sectional studies. Four major components of air pollution, including PM2.5 (particulate matter with an aerodynamic diameter of 2.5 µm or less), PM10 (particulate matter with an aerodynamic diameter of 10 µm or less), NO2, and SO2 were selected, and each analyzed for the potential impacts on insulin resistance, in the form of adjusted percentage changes in the homeostasis assessment model of insulin resistance (HOMA-IR).

RESULTS

This systematic review and meta-analysis showed that for every 1 μg/m³ increase in the concentration of selected air pollutants, PM2.5 induced a 0.40% change in HOMA-IR (95%CI: -0.03, 0.84; I2 =67.4%, p = 0.009), while PM10 induced a 1.61% change (95%CI: 0.243, 2.968; I2 =49.1%, p = 0.001). Meanwhile, the change in HOMA-IR due to increased NO2 or SO2 exposure concentration was only 0.09% (95%CI: -0.01, 0.19; I2 =83.2%, p = 0.002) or 0.01% (95%CI: -0.04, 0.06; I2 =0.0%, p = 0.638), respectively.

CONCLUSIONS

Long-term exposures to PM2.5, PM10, NO2 or SO2 are indeed associated with the odds of IR. Among the analyzed pollutants, inhalable particulate matters appear to exert greater impacts on IR.

Direct Exposure to Outdoor Air Pollution Worsens the Functional Status of Stroke Patients Treated with Mechanical Thrombectomy

Background The effect of air pollutants on the functional status of stroke patients in short-term follow-up is unknown. The aim of this study was to evaluate the effect of air pollution occurring in the stroke period and during hospitalization on the functional status of patients undergoing mechanical thrombectomy (MT). Methods Our study included stroke patients for which the individual-level exposure to ambient levels of O3, CO, SO2, NO2, PM2.5, and PM10 during the acute stroke period was assessed. The correlations between the air pollutants' concentration and the patients' functional state were analyzed. A total of 499 stroke patients (mean age: 70) were qualified. Results The CO concentration at day of stroke onset was found to be significant regarding the functional state of patients on the 10th day (OR 0.014 95% CI 0-0.908, p = 0.048). The parameters which increased the risk of death in the first 10 days were as follows: NIHSS (OR 1.27; 95% CI 1.15-1.42; p < 0.001), intracranial bleeding (OR 4.08; 95% CI 1.75-9.76; p = 0.001), and SO2 concentration on day 2 (OR 1.21; 95% CI 1.02-1.47; p = 0.03). The parameters which increased the mortality rate within 90 days include age (OR 1.07; 95% CI 1.02-1.13; p = 0.005) and NIHSS (OR 1.37; 95% CI 1.19-1.63; p < 0.001). Conclusions Exposure to air pollution with CO and SO2 during the acute stroke phase has adverse effects on the patients' functional status. A combination of parameters, such as neurological state, hemorrhagic transformation, and SO2 exposure, is unfavorable in terms of the risk of death during a hospitalization due to stroke. The risk of a worsened functional status of patients in the first month of stroke rises along with the increase in particulate matter concentrations within the first days of stroke.

Association between Ambient Particulate Air Pollution and Soluble Biomarkers of Endothelial Function: A Meta-Analysis

BACKGROUND

The burden of cardiovascular diseases caused by ambient particulate air pollution is universal. An increasing number of studies have investigated the potential effects of exposure to particulate air pollution on endothelial function, which is one of the important mechanisms for the onset and development of cardiovascular disease. However, no previous study has conducted a summary analysis of the potential effects of particulate air pollution on endothelial function.

OBJECTIVES

To summarize the evidence for the potential effects of short-term exposure to ambient particulate air pollution on endothelial function based on existing studies.

METHODS

A systematic literature search on the relationship between ambient particulate air pollution and biomarkers of endothelial function including endothelin-1 (ET-1), E-selectin, intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) was conducted in PubMed, Scopus, EMBASE, and Web of Science up to 20 May 2023. Subsequently, a meta-analysis was conducted using a random effects model.

RESULTS

A total of 18 studies were included in this meta-analysis. A 10 μg/m3 increase in short-term exposure to ambient PM2.5 was associated with a 1.55% (95% CI: 0.89%, 2.22%) increase in ICAM-1 and a 1.97% (95% CI: 0.86%, 3.08%) increase in VCAM-1. The associations of ET-1 (0.22%, 95% CI: -4.94%, 5.65%) and E-selectin (3.21%, 95% CI: -0.90% 7.49%) with short-term exposure to ambient PM2.5 were statistically insignificant.

CONCLUSION

Short-term exposure to ambient PM2.5 pollution may significantly increase the levels of typical markers of endothelial function, including ICAM-1 and VCAM-1, suggesting potential endothelial dysfunction following ambient air pollution exposure.

Concomitant exposure to air pollution, green space and noise, and risk of myocardial infarction: a cohort study from Denmark

AIMS

The three correlated environmental exposures (air pollution, road traffic noise, and green space) have all been associated with the risk of myocardial infarction (MI). The present study aimed to analyse their independent and cumulative association with MI.

METHODS AND RESULTS

In a cohort of all Danes aged 50 or older in the period 2005-17, 5-year time-weighted average exposure to fine particles (PM2.5), ultrafine particles, elemental carbon, nitrogen dioxide (NO2), and road traffic noise at the most and least exposed façades of residence was estimated. Green space around residences was estimated from land use maps. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence interval (CI), and cumulative risk indices (CRIs) were calculated. All expressed per interquartile range. Models were adjusted for both individual and neighbourhood-level socio-demographic covariates. The cohort included 1 964 702 persons. During follow-up, 71 285 developed MI. In single-exposure models, all exposures were associated with an increased risk of MI. In multi-pollutant analyses, an independent association with risk of MI was observed for PM2.5 (HR: 1.026; 95% CI: 1.002-1.050), noise at most exposed façade (HR: 1.024; 95% CI: 1.012-1.035), and lack of green space within 150 m of residence (HR: 1.018; 95% CI: 1.010-1.027). All three factors contributed significantly to the CRI (1.089; 95% CI: 1.076-1.101).

CONCLUSION

In a nationwide cohort study, air pollution, noise, and lack of green space were all independently associated with an increased risk of MI. The air pollutant PM2.5 was closest associated with MI risk.

Global association between air pollution and COVID-19 mortality: A systematic review and meta-analysis

BACKGROUND

The COVID-19 pandemic presents unprecedented challenge for global public health systems and exacerbates existing health disparities. Epidemiological evidence suggested a potential linkage between particulate and gaseous pollutants and COVID-19 mortality. We aimed to summarize the overall risk of COVID-19 mortality associated with ambient air pollutants over the short- and long-term.

METHODS

For the systematic review and meta-analysis, we searched five databases for studies evaluating the risk of COVID-19 mortality from exposure to air pollution. Inclusion of articles was assessed independently on the basis of research topic and availability of effect estimates. The risk estimates (relative risk) for each pollutant were pooled with a random-effect model. Potential heterogeneity was explored by subgroup analysis. Funnel plots and trim-and-fill methods were employed to assess and adjust for publication bias.

FINDINGS

The systematic review retrieved 2059 records, and finally included 43 original studies. PM2.5 (RR: 1.71, 95 % CI: 1.40-2.08, per 10 μg/m3 increase), NO2 (RR: 1.33, 1.07-1.65, per 10 ppb increase) and O3 (RR: 1.61, 1.00-2.57, per 10 ppb increase) were positively associated with COVID-19 mortality for long-term exposures. Accordingly, a higher risk of COVID-19 mortality was associated with PM2.5 (1.05, 1.02-1.08), PM10 (1.05, 1.01-1.08), and NO2 (1.40, 1.04-1.90) for short-term exposures. There was some heterogeneity across subgroups of income level and geographical areas.

CONCLUSION

Both long-term and short-term exposures to ambient air pollution may increase the risk of COVID-19 mortality. Future studies utilizing individual-level information on demographics, exposures, outcome ascertainment and confounders are warranted to improve the accuracy of estimates.

Influence of aerosol acidity and organic ligands on transition metal solubility and oxidative potential of fine particulate matter in urban environments

The adverse health effects of air pollution around the world have been associated with the inhalation of fine particulate matter (PM2.5). Such outcomes are thought to be related to the induction of oxidative stress due to the excess formation of reactive oxygen species (ROS) in the respiratory and cardiovascular systems. The ability of airborne chemicals to deplete antioxidants and to form ROS is known as oxidative potential (OP). Here we studied the influence of aerosol acidity and organic ligands on the solubility of transition metals, in particular iron (Fe) and copper (Cu), and on the OP of PM2.5 from Canadian National Air Pollution Surveillance urban sites in Toronto, Vancouver, and Hamilton. Using chemical assays and model simulations of the lung redox chemistry, we quantified ROS formation in the lung lining fluid, targeting superoxide anion (O2•-), hydrogen peroxide (H2O2), and hydroxyl radical (•OH), as well as the PM2.5 redox potential (RP). Experimental •OH formation (OPOH) showed high correlations with RP and model-predicted ROS metrics. Both aerosol acidity and oxalate content enhanced the solubility of transition metals, with oxalate showing a stronger association. While experimental OP metrics were primarily associated with species of primary origin such as elemental carbon, Fe, and Cu, model-predicted ROS were associated with secondary processes including proton- and ligand-mediated dissolution of Fe. Model simulations showed that water-soluble Cu was the main contributor to O2•- formation, while water-soluble Fe dominated the formation of highly reactive •OH radical, particularly at study sites with highly acidic aerosol and elevated levels of oxalate. This study underscores the importance of reducing transition metal emissions in urban environments to improve population health.

Particulate Matter Air Pollution is a Significant Risk Factor for Cardiovascular Disease

Air pollution is responsible worldwide for 9-12 million deaths annually. The major contributor to air pollution is particulate matter ≤2.5 µg per cubic meter of air (PM2.5) from vehicles, industrial emissions, and wildfire smoke. United States ambient air standards recommend annual average PM2.5 concentrations of ≤12 μg/m³ while European standards allow an average annual PM2.5 concentration of ≤20 μg/m3. However, significant PM2.5 cardiovascular and pulmonary health risks exist below these concentrations. Chronic PM2.5 exposure significantly increases major cardiovascular and pulmonary event risks in Americans by 8 to more than 20% for each 10-μg/m3 increase in PM2.5. PM2.5-induced increases in lipid peroxidation, induction of vascular inflammation and endothelial cell injury initiate and propagate respiratory diseases, coronary and carotid atherosclerosis. PM2.5 can cause atherosclerotic vascular plaque rupture and myocardial infarction and stroke by activating metalloproteinases. This article discusses PM2.5 effects on the cardiovascular and pulmonary systems, specific PM2.5 pathophysiologic mechanisms contributing to cardiopulmonary disease, and preventive measures to limit the cardiovascular and pulmonary effects of PM2.5.

Adverse effects of exposure to fine particles and ultrafine particles in the environment on different organs of organisms

Particulate pollution is a global risk factor that seriously threatens human health. Fine particles (FPs) and ultrafine particles (UFPs) have small particle diameters and large specific surface areas, which can easily adsorb metals, microorganisms and other pollutants. FPs and UFPs can enter the human body in multiple ways and can be easily and quickly absorbed by the cells, tissues and organs. In the body, the particles can induce oxidative stress, inflammatory response and apoptosis, furthermore causing great adverse effects. Epidemiological studies mainly take the population as the research object to study the distribution of diseases and health conditions in a specific population and to focus on the identification of influencing factors. However, the mechanism by which a substance harms the health of organisms is mainly demonstrated through toxicological studies. Combining epidemiological studies with toxicological studies will provide a more systematic and comprehensive understanding of the impact of PM on the health of organisms. In this review, the sources, compositions, and morphologies of FPs and UFPs are briefly introduced in the first part. The effects and action mechanisms of exposure to FPs and UFPs on the heart, lungs, brain, liver, spleen, kidneys, pancreas, gastrointestinal tract, joints and reproductive system are systematically summarized. In addition, challenges are further pointed out at the end of the paper. This work provides useful theoretical guidance and a strong experimental foundation for investigating and preventing the adverse effects of FPs and UFPs on human health.