Heart rate variability associated with particulate air pollution

The Psychophysiological Relaxation Effects of Essential Oil Combined with Still-Life Painting Activities on Older Adults in Taiwan During the COVID-19 Pandemic

Although the COVID-19 pandemic affected all types of people, older adults were disproportionately affected. Therefore, we developed an indoor program inspired by art and natural elements (plant essential oils [EOs]) intended to have a relaxing effect akin to a forest atmosphere to enhance psychophysiological health during this period. Thirty Taiwanese older adults (range, 59-79 years) participated in the study. We combined an art activity (still-life painting of vegetables) with the inhalation of Pseudotsuga menziesii and Lavandula angustifolia EOs during a 100-minute experiment. The study showed that physiological measures (heart rate, normalized low-frequency heart variability, the ratio of low- to high-frequency heart variability, high-beta waves, and gamma waves) decreased during the experiment; correspondingly, increased standard deviation of normal-to-normal intervals, normalized high-frequency heart variability, and high-alpha waves were observed, indicating relaxed physiological state. Subjective psychological assessments using the State-Trait Anxiety Inventory-State showed lower posttest scores, further supporting the relaxation effects. The psychophysiological data from this study provide important scientific evidence for the physical and mental health benefits of indoor nature-based activity programs for older adults, thereby improving their quality of life.

Kokedama and essential oils had a relaxing psychophysiological effect on Taiwanese women during the COVID-19 pandemic

BACKGROUND

During the COVID-19 pandemic, we designed an indoor nature activity program for citizens with a relaxing effect similar to forest bathing to promote their physical and mental health. We integrated an indoor horticultural activity (Kokedama) with the breathing of Pseudotsuga menziesii (P. menziesii) and Lavandula angustifolia (L. angustifolia) essential oils (EOs) with the goal of creating a nature-inspired environment in an indoor setting where participants would feel as if immersed in a forest atmosphere.

METHODS

Taiwanese women participated in the experiment, using two Saturday mornings, one Saturday in a university classroom in the city center; and the other Saturday in a workshop in a Suburban Park. Intra-group comparisons were used to assess the Physiological responses to urban and suburban environmental stimuli and measured self-reported psychological responses. We recorded parameters associated with heart-rate variability and brainwaves. We also administered the State-Trait Anxiety Inventory-State (STAI-S) questionnaire before and after the participants had completed the entire program.

RESULTS

After the participants had breathed the P. menziesii and L. angustifolia EOs, the levels of some physiological parameters increased (standard deviation of normal-to-normal intervals, normalized high frequency, and high alpha wave) and those of others decreased (normalized low frequency, low- to high-frequency ratio power, high beta wave, and gamma wave). These findings were corroborated by the data from the STAI-S questionnaires.

CONCLUSIONS

The psychophysiological data from this study provide significant scientific evidence for the health benefits of an indoor nature activity program in women.

A Dusty Road for Astronauts

The lunar dust problem was first formulated in 1969 with NASA's first successful mission to land a human being on the surface of the Moon. Subsequent Apollo missions failed to keep the dust at bay, so exposure to the dust was unavoidable. In 1972, Harrison Schmitt suffered a brief sneezing attack, red eyes, an itchy throat, and congested sinuses in response to lunar dust. Some additional Apollo astronauts also reported allergy-like symptoms after tracking dust into the lunar module. Immediately following the Apollo missions, research into the toxic effects of lunar dust on the respiratory system gained a lot of interest. Moreover, researchers believed other organ systems might be at risk, including the skin and cornea. Secondary effects could translocate to the cardiovascular system, the immune system, and the brain. With current intentions to return humans to the moon and establish a semi-permanent presence on or near the moon's surface, integrated, end-to-end dust mitigation strategies are needed to enable sustainable lunar presence and architecture. The characteristics and formation of Martian dust are different from lunar dust, but advances in the research of lunar dust toxicity, mitigation, and protection strategies can prove strategic for future operations on Mars.

Global attributed burden of death for air pollution: Demographic decomposition and birth cohort effect

BACKGROUND

To identify the high-risk pollutants and evolving patterns of attributed mortality burden, more detailed evidence is needed to examine the contribution of different air pollutants to death across the disease spectrum, particularly considering population change as well as the context of the era.

METHODS

We explored the evolving patterns of all-cause and disease-specific deaths attributed to overall air pollution and its main subcategories by using the estimated annual percentage change and additionally assessing the contribution of population growth and ageing to death burden using the decomposition method. Age-period-cohort model and Joinpoint analysis were used to evaluate birth cohort effects specific-disease death burden owing to high-risk air pollution subcategories.

FINDINGS

The number of deaths caused by air pollution increased by 2.62 %, which was driven by ambient particulate matter pollution and ambient ozone pollution, whereas household air pollution decreased. Population ageing contributed 28.88 % of the deaths increase change for air pollution. Compared with other subcategories, the age-standardized mortality rate (ASMR) attributed to ambient particulate matter pollution remained the heaviest attributed death burden, comprehensively considering of bivariate burden. In 2019, ischemic heart disease attributed to ambient particulate matter pollution exhibited the highest ASMR, which may be impacted by a rapid increase era from 1950 to 1980 birth cohort in woman and 1970 to 1990 birth cohort in man. Diabetes mellitus attributed to ambient particulate matter pollution showed the largest increase for ASMR, which was driven primarily by men born 1910-1975 and women born 1950-1975.Uzbekistan showed the highest ASMR for ischemic heart disease, with Equatorial Guinea showing the fastest increase for diabetes mellitus.

CONCLUSION

Priority intervention targets for air pollution and health should emphasize the susceptibility of the elderly population as well as the structural factors of the era, in particular sensitive diseases to the ambient particulate matter pollution.

PM2.5 exposure exacerbates mice thoracic aortic aneurysm and dissection by inducing smooth muscle cell apoptosis via the MAPK pathway

Air pollution is a major public health concern worldwide. Exposure to fine particulate matter (PM2.5) is closely associated with cardiovascular diseases. However, the effect of PM2.5 exposure on thoracic aortic aneurysm and dissection (TAAD) has not been fully elucidated. Diesel exhaust particulate (DEP) is an important component of PM2.5, which causes health effects and is closely related to the incidence of cardiovascular disease. In the current study, we found that DEP exposure increased the incidence of aortic dissection (AD) in β-aminopropionitrile (BAPN)-induced thoracic aortic aneurysm (TAA). In addition, exposure to PM2.5 increased the diameter of the thoracic aorta in mice models. The number of apoptotic cells increased in the aortic wall of PM2.5-treated mice, as did the protein expression level of BAX/Bcl2 and cleaved caspase3/caspase3. Using a rhythmically stretching aortic mechanical simulation model, fluorescent staining indicated that PM2.5 administration could induce mitochondrial dysfunction and increase reactive oxygen species (ROS) levels in human aortic smooth muscle cells (HASMCs). Furthermore, ERK1/2 mitogen-activated protein kinase (MAPK) signaling pathways participated in the apoptosis of HASMCs after PM2.5 exposure. Therefore, we concluded that PM2.5 exposure could exacerbate the progression of TAAD, which could be induced by the increased apoptosis in HASMCs through the ERK1/2 MAPK signaling pathway.

Association between air pollution exposure and coronary heart disease hospitalization in a humid sub-tropical region of China: A time-series study

Objective

Emerging evidence has highlighted the possible links of environmental pollution with several cardiovascular diseases (CVDs). The current study aimed to explore the impact of short-term air pollution exposure on CHD hospitalization in Hefei.

Methods

Data about the daily number of CHD admissions (from 2014 to 2021) were retrieved from the First Affiliated Hospital of Anhui Medical University. Air pollutants and meteorological data were obtained from the China Environmental Monitoring Station and the China Meteorological Data Service Center, respectively. The correlation between air pollution and CHD hospitalization was assessed using distributed lag non-linear model (DLNM) and Poisson generalized linear regression.

Results

In the single-pollutant model, NO₂, O₃, and CO strongly correlated with CHD hospitalization rate. Specifically, exposure to NO₂ (lag0, relative risk [RR]: 1.013, 95%CI: 1.002-1.024, per 10 μg/m³ increase) and CO (lag13, RR: 1.035, 95%CI: 1.001-1.071, per 1 μg/m³ increase) revealed a positive correlation with an increased rate of CHD hospitalization. Interestingly, O₃ had a protective association with hospitalization of CHD (lag0, RR: 0.993, 95%CI: 0.988-0.999, per 10 μg/m³ increase). Similar results, to those of the single-pollutant model, were revealed following verification using two-pollutant models. Subgroup analyses indicated that young people, women, and people in hot seasons were more susceptible to NO₂ exposure, while the elderly, women, and people in cold seasons were more susceptible to O₃. Furthermore, the elderly were more susceptible to CO exposure.

Conclusion

Overall, exposure to NO₂ and CO increases the rate of CHD hospitalization, but exposure to O₃ shows a protective association with the rate of CHD hospitalization. Therefore, early preventive measures against air pollutants should be applied to protect vulnerable patients with CHD.

Effects of Air Pollutant Exposure on Acute Myocardial Infarction

BACKGROUND

Air pollution is a consequence of industrial development that is exacerbated as a result of population growth, and urbanisation.

AIM

The goal of the study is to investigate the effects of air pollution on the number of cases of acute myocardial infarction (AMI) according to gender using the Zero-inflated Poisson Regression model in Hamadan, Iran.

METHODS

The study used an ecological design, and data collected from March 2016 to September 2020 in Hamadan were included. The intended response was the number of cases of AMI recorded in the investigated period. The time lag of the pollutants was used to investigate the effect of air pollution on the number of AMIs.

RESULTS

The number of AMI recorded for men and women was 1,195 and 553, respectively. The average age (±SD) for men and women was 64.60 (±12.27) and 70.98 (±11.79) years, respectively. According to the air quality index in Hamadan, the values of particulate matter < 2.5 μm (PM_2.5), SO₂, O₃, and CO were below moderate levels. Also, according to NO₂ and particulate matter between 25 μm-10 μm (PM₁₀), the air quality index of Hamadan was in the very unhealthy mode just for 2 and 3 days, respectively. The O₃ and NO₂ are significant positive effects on AMI among men. But, PM_2.5, PM₁₀, and SO₂ are negative impacts on hospitalisation in men due to AMI. For women, PM_2.5 and O₃ had positive effects on AMI. But, NO₂ and PM₁₀ had a significant negative impact on hospitalisation in women during different time lags.

CONCLUSIONS

The results of the study showed that if the analyses are based on gender, the responses to pollutants are different and hence the stratified analysis is important.

Cardiac Autonomic Impacts of Bushfire Smoke-A Prospective Panel Study

BACKGROUND

Air pollution is associated with cardiovascular disease and mortality. Most studies have focussed on urban or traffic-related pollution, and less is known about the impacts from bushfire smoke on cardiovascular autonomic function, although it is associated with increased sudden cardiac death and mortality. We sought to investigate its instantaneous and short-term impacts on heart rate variability (HRV).

METHODS

Twenty-four (24)-hour Holter electrocardiography (ECG) was repeated twice (during bushfire [Phase 1] and then clean air [Phase 2]) in 32 participants from two Australian towns (Warburton and Traralgon, Victoria) surrounding planned burning areas. This was compared with 10 control participants in another town (Maffra, Victoria) with two clean air assessments during the same periods. The primary HRV parameters assessed were those assessing overall HRV (Standard Deviation of Normal-to-Normal intervals [SDNN]), long-term HRV (Standard Deviation of the Average of Normal Sinus-to-Normal Sinus intervals for each 5-minutes [SDANN]), low frequency [LF]) and short-term HRV (Root Mean Square of Successive Differences between N-N intervals [RMSSD], High Frequency [HF], LF:HF ratio). Average concentrations of particulate matter <2.5 μm in diameter (PM_2.5) were measured at fixed site monitors in each location.

RESULTS

Mean PM_2.5 levels were significantly elevated during bushfire exposure in Warburton (96.5±57.7 μg/m³ vs 4.0±1.9 μg/m³, p<0.001) and Traralgon (12.6±4.9 μg/m³ vs 3.4±3.1 μg/m³, p<0.001), while it remained low in the control town, Maffra, in each phase (4.3±3.2 μg/m³ and 3.9±3.6 μg/m³, p=0.70). Although SDANN remained stable in controls, the exposed cohort showed significant worsening in SDANN during bushfire smoke exposure by 9.6±25.7ms (p=0.039). In univariable analysis, smoke exposure was significantly associated with higher ΔSDNN and ΔSDANN (p=0.03, p=0.01 exposed vs control). The association remained significant in ΔSDANN after adjusting for age, sex and cigarette smoking (p=0.02) and of borderline significance in ΔSDNN (p=0.06).

CONCLUSIONS

Exposure to the bushfire smoke was independently associated with reduced overall and long-term HRV. Our findings suggest that imbalance in cardiac autonomic function is a key mechanism of adverse cardiovascular effects of bushfire smoke.

Annual exposure to PM10 is related to cerebral small vessel disease in general adult population

Ambient air pollution is one of the most important global health issues. Although several studies have been reported the associations between air pollution and brain function or structure, impact of the air pollution on cerebral small vessel disease (cSVD) have rarely been explored in Asian adult population. We evaluated the association between exposure to air pollutants and cSVD in Korean asymptomatic adults. This cross-sectional study included 3257 participants of a health screening program from January 2006 to December 2013. All participants performed brain magnetic resonance imaging. To assess the cSVD, we considered three features such as white matter hyperintensities (WMH), silent lacunar infarction (SLI), and cerebral microbleeds (CMBs). The annual average exposure to air pollutants [particulate matter ≤ 10 μm in aerodynamic diameter (PM₁₀), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO)] was generated. The mean [standard deviation (SD)] age of the total 3257 participants was 56.5 (9.5) years, and 54.0% of them were male. Among all the included participants, 273 (8.4%) had SLI and 135 (4.1%) had CMBs. The mean volume (± SD) of WMH was 2.72 ± 6.57 mL. In result of linear regression analysis, the volume of WMH was associated with various potential factors including age, height, weight, smoking and alcohol consumption status, blood pressure (BP), hypertension, and diabetes mellitus. SLI-positive group, compared to the SLI-negative group, was older, shorter, and had higher BP as well as higher frequency of hypertension and diabetes mellitus. After adjusting for covariates, the annual average concentration of PM₁₀ was significantly associated with the volume of WMH [β (95% CI) for Model 1 = 0.082 (0.038- 0.125), p < 0.001; β (95% CI) for Model 2 = 0.060 (0.013, 0.107), p = 0.013]. CMBs were not associated with the annual average concentration of PM₁₀. No significant associations of NO₂, SO₂, and CO with cSVD were observed. In conclusion, PM₁₀ exposure is associated with significant increases in brain WMH' volume and silent lacunar infarcts in asymptomatic adults.

Environmental Stressors and the PINE Network: Can Physical Environmental Stressors Drive Long-Term Physical and Mental Health Risks?

Both psychosocial and physical environmental stressors have been linked to chronic mental health and chronic medical conditions. The psycho-immune-neuroendocrine (PINE) network details metabolomic pathways which are responsive to varied stressors and link chronic medical conditions with mental disorders, such as major depressive disorder via a network of pathophysiological pathways. The primary objective of this review is to explore evidence of relationships between airborne particulate matter (PM, as a concrete example of a physical environmental stressor), the PINE network and chronic non-communicable diseases (NCDs), including mental health sequelae, with a view to supporting the assertion that physical environmental stressors (not only psychosocial stressors) disrupt the PINE network, leading to NCDs. Biological links have been established between PM exposure, key sub-networks of the PINE model and mental health sequelae, suggesting that in theory, long-term mental health impacts of PM exposure may exist, driven by the disruption of these biological networks. This disruption could trans-generationally influence health; however, long-term studies and information on chronic outcomes following acute exposure event are still lacking, limiting what is currently known beyond the acute exposure and all-cause mortality. More empirical evidence is needed, especially to link long-term mental health sequelae to PM exposure, arising from PINE pathophysiology. Relationships between physical and psychosocial stressors, and especially the concept of such stressors acting together to impact on PINE network function, leading to linked NCDs, evokes the concept of syndemics, and these are discussed in the context of the PINE network.

PM2.5-Induced Programmed Myocardial Cell Death via mPTP Opening Results in Deteriorated Cardiac Function in HFpEF Mice

PM2.5 exposure can induce or exacerbate heart failure and is associated with an increased risk of heart failure hospitalization and mortality; however, the underlying mechanisms remain unclear. This study focuses on the potential mechanisms underlying PM2.5 induction of cardiomyocyte programmed necrosis as well as its promotion of cardiac function impairment in a mouse model of heart failure with preserved ejection fraction (HFpEF). HFpEF mice were exposed to concentrated ambient PM2.5 (CAP) (CAP group) or filtered air (FA) (FA group) for 6 weeks. Changes in myocardial pathology and cardiac function were documented for comparisons between the two groups. In vitro experiments were performed to measure oxidative stress and mitochondrial permeability transition pore (mPTP) dynamics in H9C2 cells following 24 h exposure to PM2.5. Additionally, co-immunoprecipitation was conducted to detect p53 and cyclophilin D (CypD) interactions. The results showed exposure to CAP promoted cardiac function impairment in HFpEF mice. Myocardial pathology analysis and in vitro experiments demonstrated that PM2.5 led to mitochondrial damage in cardiomyocytes and, eventually, their necrosis. Moreover, our experiments also suggested that PM2.5 increases mitochondrial reactive oxygen species (ROS), induces DNA oxidative damage, and decreases the inner mitochondrial membrane potential (ΔΨm). This indicates the presence of mPTP opening. Co-immunoprecipitation results showed a p53/CypD interaction in the myocardial tissue of HFpEF mice in the CAP group. Inhibition of CypD by cyclosporin A was found to reverse PM2.5-induced mPTP opening and H9C2 cell death. In conclusion, PM2.5 induces mPTP opening to stimulate mitochondria-mediated programmed necrosis of cardiomyocytes, and it might exacerbate cardiac function impairment in HFpEF mice.

Inhalation of PM2.5 from diesel exhaust promote impairment of mitochondrial bioenergetics and dysregulate mitochondrial quality in rat heart: implications in isoproterenol-induced myocardial infarction model

Aim: Ambient exposure of PM_2.5 from diesel exhaust (termed as diesel particulate matter [DPM]) can induce cardiotoxicity that can be manifested into myocardial ischemia/infarction, where the survival depends on mitochondrial function. The mechanism for DPM-induced mitochondrial dysfunction is yet to be elucidated and the consequential impact of impaired mitochondria on the severity of myocardial infarction (MI) has not been established.Materials and methods: Female Wistar rats were exposed to DPM (0.5 mg/ml) for 3 h daily (to achieve a PM_2.5 concentration of 250 µg/m³) for 21 d trailed by an induction of MI using isoproterenol (ISO).Conclusion: DPM exposure altered the basal ECG pattern and increased heart weight (HW) to body weight (BW) ratio from control. Loss of mitochondrial quality in the cardiac tissue was observed in DPM exposed animals, measured via declined ETC enzyme activity, reduced ATP levels, high oxidative stress, low mitochondrial copy number, and low expression of the mitochondrial genes involved in mitophagy (PINK and PARKIN) and mitochondrial fusion (MFN-1). Subsequent induction of MI in DPM exposed animals (DPM + ISO) further deteriorated the normal sinus rhythm, accompanied by elevated plasma CK and LDH level, increased myocardial caspase activity, downregulation of Peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α), transcription factor A (TFAM), DNA polymerase subunit gamma (POLG), and other mitochondrial quality control genes. Based on these results, we conclude that DPM alters the electrophysiology and ultrastructure of the heart that aggravates the MI-induced cardiotoxicity, where the diminished mitochondrial quality can be the potential contributor.

The impact of social disadvantage on autonomic physiology of latinx adolescents: The role of environmental risks

The experience of poverty embodies complex, multidimensional stressors that may adversely affect physiological and psychological domains of functioning. Compounded by racial/ethnic discrimination, the financial aspect of family poverty typically coincides with additional social and physical environmental risks such as pollution exposure, housing burden, elevated neighborhood unemployment, and lower neighborhood education levels. In this study, we investigated the associations of multidimensional social disadvantage throughout adolescence with autonomic nervous system (ANS) functioning at 17 years. Two hundred and twenty nine low-income Mexican-American adolescents (48.6% female) and their parents were assessed annually between the ages of 10 and 16. Participants' census tracts were matched with corresponding annual administrative data of neighborhood housing burden, education, unemployment, drinking water quality, and fine particulate matter. We combined measures of adolescents' electrodermal response and respiratory sinuses arrhythmia at rest and during a social exclusion challenge (Cyberball) to use as ANS indices of sympathetic and parasympathetic activity, respectively. Controlling for family income-to-needs, youth exposed to greater cumulative water and air pollution from ages 10-16 displayed altered patterns of autonomic functioning at rest and during the social challenge. Conversely, youth living in areas with higher housing burden displayed healthy patterns of autonomic functioning. Altogether, results suggest that toxin exposure in youths' physical environments disrupts the ANS, representing a plausible mechanism by which pollutants and social disadvantage influence later physical and mental health.

Influence of Nicotine from Diverse Delivery Tools on the Autonomic Nervous and Hormonal Systems

Background: Through measurements of the heart rate variability (HRV) accompanied by the pertinent biomarker assays, the effects of nicotine and byproducts derived from alternative nicotine delivery systems (ANDS) on the autonomic nervous system (ANS) and hormonal system have been investigated. Methods: HRV was studied in a group of volunteers (17 people), involving non-smokers, i.e., who never smoked before (11), ex-smokers (4) and active smokers (2). ANDS and smoking simulators, including regular, nicotine-free and electronic cigarettes; tobacco heating systems; chewing gums and nicotine packs of oral fixation (nic-packs), were used. Blood pressure, levels of stress hormones in saliva and catecholamines in the blood were also monitored. Results: HRV analysis showed relatively small changes in HRV and in the other studied parameters with the systemic use of nic-packs with low and moderate nicotine contents (up to 6 mg) compared to other ANDS. Conclusions: The HRV method is proven to be a promising technique for evaluation of the risks associated with smoking, dual use of various ANDS and studying the biomedical aspects of smoking cessation. Nic-packs are shown to be leaders in biological safety among the studied ANDS. A sharp surge in the activity of the sympathetic division of the ANS within the first minutes of the use of nicotine packs implies that nicotine begins to act already at very low doses (before entering the blood physically in any significant amount) through fast signal transmission to the brain from the nicotinic and taste buds located in the mouth area.

Air pollution and cardiovascular disease: Can the Australian bushfires and global COVID-19 pandemic of 2020 convince us to change our ways?

Air pollution is a major global challenge for a multitude of reasons. As a specific concern, there is now compelling evidence demonstrating a causal relationship between exposure to airborne pollutants and the onset of cardiovascular disease (CVD). As such, reducing air pollution as a means to decrease cardiovascular morbidity and mortality should be a global health priority. This review provides an overview of the cardiovascular effects of air pollution and uses two major events of 2020-the Australian bushfires and COVID-19 pandemic lockdown-to illustrate the relationship between air pollution and CVD. The bushfires highlight the substantial human and economic costs associated with elevations in air pollution. Conversely, the COVID-19-related lockdowns demonstrated that stringent measures are effective at reducing airborne pollutants, which in turn resulted in a potential reduction in cardiovascular events. Perhaps one positive to come out of 2020 will be the recognition that tough measures are effective at reducing air pollution and that these measures have the potential to stop thousands of deaths from CVD.

Association of Particulate Matter from Cooking Oil Fumes with Heart Rate Variability and Oxidative Stress

Many studies have reported various cardiovascular autonomic responses to ambient particulate matter (PM) pollution, but few have reported such responses to occupational PM exposures. Even fewer have demonstrated a relationship between PM pollution and oxidative stress in humans. This panel study evaluates the association between occupational exposure to PM in cooking oil fumes (COFs), and changes in both heart rate variability (HRV) and oxidative stress responses in 54 male Chinese cooks. Linear mixed-effects regression models were adopted to estimate the strength of the association between PM and HRV. Participants' pre- and post-workshift urine samples were analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). Exposure to PM in COFs from 15 min to 2 h were associated with a decrease in HRV and an increase in heart rate among cooks. The urinary 8-OHdG levels of cooks were significantly elevated after workshift exposure to COFs. The levels of PM2.5, PM1.0, and particulate benzo(a)pyrene in COFs were all positively correlated with cross-workshift urinary 8-OHdG levels. Furthermore, the levels of benzo(a)pyrene in COFs were positively correlated with cross-workshift urinary MDA levels. The effects of COFs on HRV were independent of cross-workshift urinary 8-OHdG levels. Exposure to COFs leads to disturbed autonomic function and an increased risk of oxidative DNA injury among cooks in Chinese restaurants.

"ST-elevation myocardial infarction associated with air pollution levels in Mexico City"

Background Coronary heart disease has multiple risk factors, including air pollution. Numerous pathophysiological mechanisms have been identified with increasing levels of air pollution, mainly with ozone (O3), nitrogen dioxide (NO2), sulphur dioxide (SO2), particulate matter (PM10), fine particulate matter (PM2.5) and carbon monoxide (CO). In Mexico, the pollution level is reported using an air quality index called IMECA. Methods All patients with STEMI admitted at Hospital Español were collected between 2012 and 2019 (N = 348). We conducted a retrospective analysis using the air pollution exposure at the time of each event (lag0), the previous 24 h (lag1), 48 h (lag2), 72 h (lag3) and 5-day cumulative lag. The level of air pollution was analyzed independently using IMECA and particle concentrations. The data was divided in two groups: days with one of more STEMI’s (MI group) and days free of events (Control group), using ANCOVA to evaluate the difference between means of both groups taking into account confounders. Results: For days with one or more cardiovascular event, a significant increase in SO2 was observed at lag1; similar increase was found in CO, PM2.5, SO2 at lag2. For the 5-day cumulative lag, SO2 and PM2.5 showed a significant increase. No differences were found using the IMECA levels in both groups. Conclusions: The elevated concentrations levels of CO, SO2 and PM2.5 showed significant association with STEMI at different time points before the event. Ozone, PM10 and NO2 showed no difference between groups. IMECA levels showed no association with STEMI in our study.

Administration of Lactobacillus paracasei HB89 mitigates PM2.5-induced enhancement of inflammation and allergic airway response in murine asthma model

PM2.5 causes abnormal immune response and asthma in animals. In this study, a Balb/c mouse animal model was exposed to PM2.5 to induce asthma. Lactobacillus paracasei HB89 was fed at the same time, in order to observe whether L. paracasei HB89 mitigates respiratory tract allergies stimulated by PM2.5. The results showed that PM2.5 stimulated a significant increase in white blood cells and immunoglobulin (IgE) in OVA-induced allergic Balb/c mice, and IgE in the blood further triggered the release of histamine in the lung immune cells. This not only increased overall immune cell counts, but the lymphocyte counts also increased significantly, resulting in significant inhibitions of cytokines INF-r and TGF-β, and induction of IL-4, IL-5, IL-13 and IL-17a. After feeding with HB89, apart from the absence of observable changes in body weight, the total white blood cell count in the animal blood and IgE response were also be reduced; the proliferation of immune cells in the lungs caused by PM2.5 was slowed down; and histamine and cytokines INF-r and TGF-β were secreted in large quantities, but IL- 4, IL-5, IL-13, IL-17a were inhibited, which effectively reduced the possibility of asthma induction.

"Acute Myocardial Infarction in the Time of COVID-19": A Review of Biological, Environmental, and Psychosocial Contributors

Coronavirus disease 2019 (COVID-19) has quickly become a worldwide health crisis.Although respiratory disease remains the main cause of morbidity and mortality in COVID patients,myocardial damage is a common finding. Many possible biological pathways may explain therelationship between COVID-19 and acute myocardial infarction (AMI). Increased immune andinflammatory responses, and procoagulant profile have characterized COVID patients. All theseresponses may induce endothelial dysfunction, myocardial injury, plaque instability, and AMI.Disease severity and mortality are increased by cardiovascular comorbidities. Moreover, COVID-19has been associated with air pollution, which may also represent an AMI risk factor. Nonetheless,a significant reduction in patient admissions following containment initiatives has been observed,including for AMI. The reasons for this phenomenon are largely unknown, although a real decreasein the incidence of cardiac events seems highly improbable. Instead, patients likely may presentdelayed time from symptoms onset and subsequent referral to emergency departments because offear of possible in-hospital infection, and as such, may present more complications. Here, we aim todiscuss available evidence about all these factors in the complex relationship between COVID-19and AMI, with particular focus on psychological distress and the need to increase awareness ofischemic symptoms.

Long-term PM2.5 exposure and the clinical application of machine learning for predicting incident atrial fibrillation

Clinical impact of fine particulate matter (PM_2.5) air pollution on incident atrial fibrillation (AF) had not been well studied. We used integrated machine learning (ML) to build several incident AF prediction models that include average hourly measurements of PM_2.5 for the 432,587 subjects of Korean general population. We compared these incident AF prediction models using c-index, net reclassification improvement index (NRI), and integrated discrimination improvement index (IDI). ML using the boosted ensemble method exhibited a higher c-index (0.845 [0.837-0.853]) than existing traditional regression models using CHA₂DS₂-VASc (0.654 [0.646-0.661]), CHADS₂ (0.652 [0.646-0.657]), or HATCH (0.669 [0.661-0.676]) scores (each p < 0.001) for predicting incident AF. As feature selection algorithms identified PM_2.5 as a highly important variable, we applied PM_2.5 for predicting incident AF and constructed scoring systems. The prediction performances significantly increased compared with models without PM_2.5 (c-indices: boosted ensemble ML, 0.954 [0.949-0.959]; PM-CHA₂DS₂-VASc, 0.859 [0.848-0.870]; PM-CHADS₂, 0.823 [0.810-0.836]; or PM-HATCH score, 0.849 [0.837-0.860]; each interaction, p < 0.001; NRI and IDI were also positive). ML combining readily available clinical variables and PM_2.5 data was found to predict incident AF better than models without PM_2.5 or even established risk prediction approaches in the general population exposed to high air pollution levels.

Oxygenated polycyclic aromatic hydrocarbons from ambient particulate matter induce electrophysiological instability in cardiomyocytes

Background

Epidemiologic studies have suggested that elevated concentrations of particulate matter (PM) are strongly associated with an increased risk of developing cardiovascular diseases, including arrhythmia. However, the cellular and molecular mechanisms by which PM exposure causes arrhythmia and the component that is mainly responsible for this adverse effect remains to be established. In this study, the arrhythmogenicity of mobilized organic matter from two different types of PM collected during summer (SPM) and winter (WPM) seasons in the Seoul metropolitan area was evaluated. In addition, differential effects between polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (oxy-PAHs) on the induction of electrophysiological instability were examined.

Results

We extracted the bioavailable organic contents of ambient PM, measuring 10 μm or less in diameter, collected from the Seoul metropolitan area using a high-volume air sampler. Significant alterations in all factors tested for association with electrophysiological instability, such as intracellular Ca²⁺ levels, reactive oxygen species (ROS) generation, and mRNA levels of the Ca²⁺-regulating proteins, sarcoplasmic reticulum Ca²⁺ATPase (SERCA2a), Ca²⁺/calmodulin-dependent protein kinase II (CaMK II), and ryanodine receptor 2 (RyR2) were observed in cardiomyocytes treated with PM. Moreover, the alterations were higher in WPM-treated cardiomyocytes than in SPM-treated cardiomyocytes. Three-fold more oxy-PAH concentrations were observed in WPM than SPM. As expected, electrophysiological instability was induced higher in oxy-PAHs (9,10-anthraquinone, AQ or 7,12-benz(a) anthraquinone, BAQ)-treated cardiomyocytes than in PAHs (anthracene, ANT or benz(a) anthracene, BaA)-treated cardiomyocytes; oxy-PAHs infusion of cells mediated by aryl hydrocarbon receptor (AhR) was faster than PAHs infusion. In addition, ROS formation and expression of calcium-related genes were markedly more altered in cells treated with oxy-PAHs compared to those treated with PAHs.

Conclusions

The concentrations of oxy-PAHs in PM were found to be higher in winter than in summer, which might lead to greater electrophysiological instability through the ROS generation and disruption of calcium regulation.

Total sulfur analysis of fine particulate mass on nylon filters by ICP-OES

Sulfur (S) and sulfate (SO₄ ^2- ) in fine particulate matter (PM_2.5 ) are monitored by the Interagency Monitoring of Protected Visual Environments (IMPROVE) network at remote and rural sites across the United States. Within the IMPROVE network, S is determined from X-ray fluorescence (XRF) spectroscopy from a Teflon filter, and SO₄ ^2- is determined via ion chromatography (IC) from a nylon filter. Differences in S and SO₄ ^2- estimates may indicate the presence of organosulfur (OS) species or biases between sampling and analytical methods. To reduce potential biases, an inductively coupled plasma-optical emission spectroscopy (ICP-OES) method was developed to allow for analysis of SO₄ ^2- and S from a single filter extract. Sulfur (ICP-OES) and SO₄ ^2- (IC) estimates from 2016 IMPROVE filters correlated strongly, suggesting that, on average, ICP-OES accurately estimated S. However, observed differences between slopes suggested the presence of water-soluble OS species, especially during summer. Organosulfur species are important indicators of secondary organic aerosols formed through reactions of biogenic and anthropogenic pollutants and can be quantified through laboratory techniques such as reverse-phase liquid chromatography (RPLC) or hydrophilic liquid interaction chromatography (HILIC) coupled to electrospray ionization-high-resolution tandem mass spectrometry (RPLC/ESI-HR-MS/MS and HILIC/ESI-HR-MS/MS, respectively), and field techniques using Aerodyne aerosol mass spectrometry (AMS). However, these methods are costly and introduce relatively large uncertainties when scaled for large networks such as IMPROVE. The method described in this report provides an inexpensive complement to XRF, which measures total S (insoluble and water-soluble S) to estimate water-soluble S and OS concentrations in PM.

Air pollution and cardiovascular disease: car sick

The cardiovascular effects of inhaled particle matter (PM) are responsible for a substantial morbidity and mortality attributed to air pollution. Ultrafine particles, like those in diesel exhaust emissions, are a major source of nanoparticles in urban environments, and it is these particles that have the capacity to induce the most significant health effects. Research has shown that diesel exhaust exposure can have many detrimental effects on the cardiovascular system both acutely and chronically. This review provides an overview of the cardiovascular effects on PM in air pollution, with an emphasis on ultrafine particles in vehicle exhaust. We consider the biological mechanisms underlying these cardiovascular effects of PM and postulate that cardiovascular dysfunction may be implicated in the effects of PM in other organ systems. The employment of multiple strategies to tackle air pollution, and especially ultrafine particles from vehicles, is likely to be accompanied by improvements in cardiovascular health.

Synergic effect between high temperature and air pollution on mortality in Northeast Asia

High temperature and air pollutants have been reported as potential risk factors of mortality. Previous studies investigated interaction between the two variables; however, the excess death risk due to the synergic effect (i.e. interaction on the additive scale) between the two variables has not been investigated adequately on a multi-country scale. This study aimed to assess the excess death risk due to the synergism between high temperature and air pollution on mortality using a multicity time-series analysis. We collected time-series data on mortality, weather variables, and four air pollutants (PM₁₀, O₃, NO₂, and CO) for 16 metropolitan cities of three countries (Japan, Korea, and Taiwan) in Northeast Asia (1979-2015). Quasi-Poisson time-series regression and meta-analysis were used to estimate the additive interaction between high temperature and air pollution. The additive interaction was measured by relative excess risk due to interaction (RERI) index. We calculated RERI with relative risks (RR) of the 99th/10th, 90th/90th, and 99th/90th percentiles of temperature/air pollution metrics, where risk at the 90th/10th percentiles of temperature/air pollution metrics was the reference category. This study showed that there may exist positive and significant excess death risks due to the synergism between high temperature and air pollution in the total population for all pollutants (95% lower confidence intervals of all RERIs>0 or near 0). In final, we measured quantitatively the excess death risks due to synergic effect between high temperature and air pollution, and the synergism should be considered in public health interventions and a composite warning system.

Novel evidence for a greater burden of ambient air pollution on cardiovascular disease

Ambient and household air pollution is a major health problem worldwide, contributing annually to approximately seven million of all-cause avoidable deaths, shorter life expectancy, and significant direct and indirect costs for the community. Air pollution is a complex mixture of gaseous and particulate materials that vary depending on their source and physicochemical features. Each material has detrimental effects on human health, but a number of experimental and clinical studies have shown a strong impact for fine particulate matter (PM_2.5). In particular, there is more and more evidence that PM_2.5 exerts adverse effects particularly on the cardiovascular system, contributing substantially (mainly through mechanisms of atherosclerosis, thrombosis and inflammation) to coronary artery and cerebrovascular disease, but also to heart failure, hypertension, diabetes and cardiac arrhythmias. In this review, we summarize knowledge on the mechanisms and magnitude of the cardiovascular adverse effects of short-and long-term exposure to ambient air pollution, particularly for the PM_2.5 size fraction. We also emphasize that very recent data indicate that the global mortality and morbidity burden of cardiovascular disease associated with this air pollutant is dramatically greater than what has been thought up to now.

Fine Particle Air Pollution and Physiological Reactivity to Social Stress in Adolescence: The Moderating Role of Anxiety and Depression

OBJECTIVE

Exposure to high levels of fine particle air pollution (PM2.5) is associated with adolescent pathophysiology. It is unclear, however, if PM2.5 is associated with physiology within psychosocial contexts, such as social stress, and whether some adolescents are particularly vulnerable to PM2.5-related adverse effects. This study examined the association between PM2.5 and autonomic reactivity to social stress in adolescents and tested whether symptoms of anxiety and depression moderated this association.

METHODS

Adolescents from Northern California (N = 144) participated in a modified Trier Social Stress Test while providing high-frequency heart rate variability and skin conductance level data. PM2.5 data were recorded from CalEnviroScreen. Adolescents reported on their own symptoms of anxiety and depression using the Youth Self-Report, which has been used in prior studies and has good psychometric properties (Cronbach's α in this sample was .86).

RESULTS

Adolescents residing in neighborhoods characterized by higher concentrations of PM2.5 demonstrated greater autonomic reactivity (i.e., indexed by lower heart rate variability and higher skin conductance level) (β = .27; b = .44, p = .001, 95% CI = 0.19 to 0.68) in response to social stress; this association was not accounted for by socioeconomic factors. In addition, adolescents who reported more severe anxiety and depression symptoms showed the strongest association between PM2.5 and autonomic reactivity to social stress (β = .53; b = .86, p < .001, 95% CI = 0.48 to 1.23).

CONCLUSIONS

Exposure to PM2.5 may heighten adolescent physiological reactivity to social stressors. Moreover, adolescents who experience anxiety and depression may be particularly vulnerable to the adverse effects of PM2.5 on stress reactivity.

Synthesis of Harvard Environmental Protection Agency (EPA) Center studies on traffic-related particulate pollution and cardiovascular outcomes in the Greater Boston Area

The association between particulate pollution and cardiovascular morbidity and mortality is well established. While the cardiovascular effects of nationally regulated criteria pollutants (e.g., fine particulate matter [PM_2.5] and nitrogen dioxide) have been well documented, there are fewer studies on particulate pollutants that are more specific for traffic, such as black carbon (BC) and particle number (PN). In this paper, we synthesized studies conducted in the Greater Boston Area on cardiovascular health effects of traffic exposure, specifically defined by BC or PN exposure or proximity to major roadways. Large cohort studies demonstrate that exposure to traffic-related particles adversely affect cardiac autonomic function, increase systemic cytokine-mediated inflammation and pro-thrombotic activity, and elevate the risk of hypertension and ischemic stroke. Key patterns emerged when directly comparing studies with overlapping exposure metrics and population cohorts. Most notably, cardiovascular risk estimates of PN and BC exposures were larger in magnitude or more often statistically significant compared to those of PM_2.5 exposures. Across multiple exposure metrics (e.g., short-term vs. long-term; observed vs. modeled) and different population cohorts (e.g., elderly, individuals with co-morbidities, young healthy individuals), there is compelling evidence that BC and PN represent traffic-related particles that are especially harmful to cardiovascular health. Further research is needed to validate these findings in other geographic locations, characterize exposure errors associated with using monitored and modeled traffic pollutant levels, and elucidate pathophysiological mechanisms underlying the cardiovascular effects of traffic-related particulate pollutants. Implications: Traffic emissions are an important source of particles harmful to cardiovascular health. Traffic-related particles, specifically BC and PN, adversely affect cardiac autonomic function, increase systemic inflammation and thrombotic activity, elevate BP, and increase the risk of ischemic stroke. There is evidence that BC and PN are associated with greater cardiovascular risk compared to PM_2.5. Further research is needed to elucidate other health effects of traffic-related particles and assess the feasibility of regulating BC and PN or their regional and local sources.

Exposure to air pollution is associated with adverse cardiopulmonary health effects in international travellers

BACKGROUND

With the number of annual global travellers reaching 1.2 billion, many individuals encounter greater levels of air pollution when they travel abroad to megacities around the world. This study's objective was to determine if visits to cities abroad with greater levels of air pollution adversely impact cardiopulmonary health.

METHODS

A total of 34 non-smoking healthy adult participants who travelled abroad to selected cities from the New York City (NYC) metropolitan area were pre-trained to measure lung function, blood pressure and heart rate (HR)/HR variability (HRV) and record symptoms before, during and after travelling abroad. Outdoor particulate matter (PM)2.5 concentrations were obtained from central monitors in each city. Associations between PM exposure concentrations and cardiopulmonary health endpoints were analysed using a mixed effects statistical design.

RESULTS

East and South Asian cities had significantly higher PM2.5 concentrations compared with pre-travel NYC PM2.5 levels, with maximum concentrations reaching 503 μg/m3. PM exposure-related associations for lung function were statistically significant and strongest between evening Forced Expiratory Volume in the first second (FEV1) and same-day morning PM2.5 concentrations; a 10-μg/m3 increase in outdoor PM2.5 was associated with a mean decrease of 7 mL. Travel to a highly polluted city (PM2.5 > 100 μg/m3) was associated with a 209-ml reduction in evening FEV1 compared with a low polluted city (PM2.5 < 35 μg/m3). In general, participants who travelled to East and South Asian cities experienced increased respiratory symptoms/scores and changes in HR and HRV.

CONCLUSIONS

Exposure to increased levels of PM2.5 in cities abroad caused small but statistically significant acute changes in cardiopulmonary function and respiratory symptoms in healthy young adults. These data suggest that travel-related exposure to increased PM2.5 adversely impacts cardiopulmonary health, which may be particularly important for travellers with pre-existing respiratory or cardiac disease.

Time-Stratified Case Crossover Study of the Association of Outdoor Ambient Air Pollution With the Risk of Acute Myocardial Infarction in the Context of Seasonal Exposure to the Southeast Asian Haze Problem

Background Prior studies have demonstrated the association of air pollution with cardiovascular deaths. Singapore experiences seasonal transboundary haze. We investigated the association between air pollution and acute myocardial infarction ( AMI ) incidence in Singapore. Methods and Results We performed a time-stratified case-crossover study on all AMI cases in the Singapore Myocardial Infarction Registry (2010-2015). Exposure on days where AMI occurred (case days) were compared with the exposure on days where AMI did not occur (control days). Control days were chosen on the same day of the week earlier and later in the same month and year. We fitted conditional Poisson regression models to daily AMI incidence to include confounders such as ambient temperature, rainfall, wind-speed, and Pollutant Standards Index. We assessed relationships between AMI incidence and Pollutant Standards Index in the entire cohort and subgroups of individual-level characteristics. There were 53 948 cases. Each 30-unit increase in Pollutant Standards Index was association with AMI incidence (incidence risk ratio [ IRR ] 1.04, 95% CI 1.03-1.06). In the subgroup of ST -segment-elevation myocardial infarction the IRR was 1.00, 95% CI 0.98 to 1.03, while for non-ST-segment-elevation myocardial infarction, the IRR was 1.08, 95% CI 1.05 to 1.10. Subgroup analyses showed generally significant. Moderate/unhealthy Pollutant Standards Index showed association with AMI occurrence with IRR 1.08, 95% CI 1.05 to 1.11 and IRR 1.09, 95% CI 1.01 to 1.18, respectively. Excess risk remained elevated through the day of exposure and for >2 years after. Conclusions We found an effect of short-term air pollution on AMI incidence, especially non-ST-segment-elevation myocardial infarction and inpatient AMI . These findings have public health implications for primary prevention and emergency health services during haze.

Sympathoexcitation in response to cardiac and pulmonary afferent stimulation of TRPA1 channels is attenuated in rats with chronic heart failure

Excessive sympathoexcitation characterizes the chronic heart failure (CHF) state. An exaggerated cardiac sympathetic afferent reflex (CSAR) contributes to this sympathoexcitation. Prior studies have demonstrated that the CSAR to capsaicin [transient receptor potential (TRP) vanilloid 1 agonist] is exaggerated in CHF animal models. We recently discovered that capsaicin application to the lung visceral pleura in anesthetized, vagotomized, open-chested rats increases mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA). We named this response the pulmonary spinal afferent reflex (PSAR). Due to the similarities between TRP vanilloid 1 and TRP ankyrin 1 (TRPA1) channels as well as the excessive sympathoexcitation of CHF, we hypothesized that stimulation of the CSAR and PSAR with a specific TRPA1 agonist would result in an augmented response in CHF rats (coronary ligation model) compared with sham control rats. In response to a TRPA1 agonist, both CSAR and PSAR in sham rats resulted in biphasic changes in MAP and increases in HR and RSNA 10-12 wk postmyocardial infarction (post-MI). These effects were blunted in CHF rats. Assessment of TRPA1 expression levels in cardiopulmonary spinal afferents by immunofluorescence, quantitative RT-PCR, and Western blot analysis 10-12 wk post-MI all indicates reduced expression in CHF rats but no reduction at earlier time points. TRPA1 protein was reduced in a dorsal root ganglia cell culture model of inflammation and simulated tissue ischemia, raising the possibility that the in vivo reduction of TRPA1 expression was, in part, caused by CHF-related tissue ischemia and inflammation. These data provide evidence that reflex responses to cardiopulmonary spinal afferent TRPA1 stimulation may be attenuated in CHF rather than enhanced. NEW & NOTEWORTHY Excessive sympathoexcitation characterizes chronic heart failure (CHF). The contribution of transient receptor potential ankyrin 1 (TRPA1) channel-mediated reflexes to this sympathoexcitation is unknown. We found that application of TRPA1 agonist to the heart and lung surface resulted in increased heart rate and sympathetic output and a biphasic change in mean arterial pressure in control rats. These effects were attenuated in CHF rats, decreasing the likelihood that TRPA1 channels contribute to cardiopulmonary afferent sensitization in CHF.

Association between Atmospheric Particulate Pollutants and Mortality for Cardio-Cerebrovascular Diseases in Chinese Korean Population: A Case-Crossover Study

Background: Air pollution in large Chinese cities has led to recent studies that highlighted the relationship between particulate matters (PM) and elevated risk of cardio-cerebrovascular mortality. However, it is unclear as to whether: (1) The same adverse relations exist in cities with relatively low levels of air pollution; and (2) the relationship between the two are similar across ethnic groups. Methods: We collected data of PM_2.5 (PM with an aerodynamic diameter ≤ 2.5 µm) and PM₁₀ (aerodynamic diameter ≤ 10 µm) in the Yanbian Korean Autonomous Prefecture between 1 January 2015 and 31 December 2016. Using a time-stratified case-crossover design, we investigated whether levels of particulate pollutants influence the risk of cardio-cerebrovascular disease mortality among ethnic Korean vs. ethnic Han residents residing in the Yanbian Korean Autonomous Prefecture. Results: Under the single air pollutant model, the odds ratios (ORs) of cardio-cerebrovascular disease were 1.025 (1.024–1.026) for each 10 μg/m³ increase in PM_2.5 at lag0 day, 1.012 (1.011–1.013) for each 10 μg/m³ increase in PM₁₀ at lag1 day. In the multi-pollutant model adjusted by PM₁₀, SO₂, and NO₂, the ORs of cardio-cerebrovascular disease were 1.150 (1.145–1.155) for ethnic Koreans and 1.154 (1.149–1.158) for ethnic Hans for each 10 μg/m³ increase in PM_2.5. In the multi-pollutant model adjusted by PM_2.5, SO₂, and NO₂, the ORs of cardio-cerebrovascular disease were 1.050 (1.047–1.053) for ethnic Koreans and 1.041 (1.039–1.043) for ethnic Hans for each 10 μg/m³ increase in PM₁₀. Conclusion: This study showed that PM_2.5 and PM₁₀ were associated with increased risks of acute death events in residential cardio-cerebrovascular disease in Yanbian, China.

Chitosan oligosaccharides alleviate PM2.5-induced lung inflammation in rats

Air pollution of particulate matter (PM), especially PM_2.5, has become a major public health problem in China. Exploration of therapeutic and preventive measures against PM_2.5 toxicity is of practical significance. The aim of this study was to examine the inhibitory effects of chitosan oligosaccharides (COS) on PM_2.5-induced lung inflammation in rats. Forty SPF (specific pathogen-free) male Wistar rats weighing 200-220 g were randomly divided into four groups: control group, COS group, PM_2.5 group, and PM_2.5+COS group. COS was pre-administered to rats by gavage at a single dose of 500 mg/kg 2 h before intratracheal instillation of PM_2.5 at a single dose of 1.2 mg/kg daily for 3 consecutive days. Normal saline (NS) was used as negative control. Twenty-four hours after the last instillation of PM_2.5, rats were sacrificed and subjected to bronchoalveolar lavage (BAL). The BAL fluids (BALF) were collected for measurement of levels of total proteins, lactate dehydrogenase (LDH), interleukin-1 (IL-1β), IL-8, and tumor necrosis factor-ɑ (TNF-ɑ) using colorimetric or ELISA kits. Levels of total proteins, LDH activities, and pro-inflammatory mediators including IL-1β, IL-8, and TNF-ɑ in BALF of rats in PM_2.5 group significantly increased in comparison with those of the control group. Pre-treatment of rats with COS markedly blocked PM_2.5-induced increase in LDH, IL-8, and TNF-ɑ levels in BALF. In conclusion, PM_2.5 exposure induces rat lung inflammation, which could be ameliorated by the pre-treatment of COS.

Particulate Matter Air Pollution: Effects on the Cardiovascular System

Air pollution is a complex mixture of gaseous and particulate components, each of which has detrimental effects on human health. While the composition of air pollution varies greatly depending on the source, studies from across the world have consistently shown that air pollution is an important modifiable risk factor for significantly increased morbidity and mortality. Moreover, clinical studies have generally shown a greater impact of particulate matter (PM) air pollution on health than the gaseous components. PM has wide-ranging deleterious effects on human health, particularly on the cardiovascular system. Both acute and chronic exposure to PM air pollution is associated with increased risk of death from cardiovascular diseases including ischemic heart disease, heart failure, and ischemic/thrombotic stroke. Particulate matter has also been shown to be an important endocrine disrupter, contributing to the development of metabolic diseases such as obesity and diabetes mellitus, which themselves are risk factors for cardiovascular disease. While the epidemiological evidence for the deleterious effects of PM air pollution on health is increasingly accepted, newer studies are shedding light on the mechanisms by which PM exerts its toxic effects. A greater understanding of how PM exerts toxic effects on human health is required in order to prevent and minimize the deleterious health effects of this ubiquitous environmental hazard. Air pollution is a growing public health problem and mortality due to air pollution is expected to double by 2050. Here, we review the epidemiological evidence for the cardiovascular effects of PM exposure and discuss current understanding about the biological mechanisms, by which PM exerts toxic effects on cardiovascular system to induce cardiovascular disease.

Cardiovascular benefits of short-term indoor air filtration intervention in elderly living in Beijing: An extended analysis of BIAPSY study

BACKGROUND

Adverse cardiovascular effects associated with air pollution exposure have been widely demonstrated. However, inconsistent cardiovascular responses were observed from reducing indoor air pollution exposure. We aimed to assess whether short-term air filtration intervention could benefit cardiovascular health in elderly living in high pollution area.

METHODS

A randomized crossover intervention study of short-term indoor air filtration intervention on cardiovascular health was conducted among 35 non-smoking elderly participants living in Beijing in the winter of 2013, as part of Beijing Indoor Air Purifier StudY (BIAPSY). Portable air filtration units were randomly allocated to active filtration for 2 weeks and sham filtration for 2 weeks in the households. Twelve-hour daytime ambulatory heart rate variability (HRV) and blood pressure (ABP) were measured during active and sham filtration. Concurrently, real-time indoor and outdoor particulate matter with diameter less than 2.5 µm (PM_2.5) and indoor black carbon (BC) concentrations were measured. We applied generalized additive mixed models to evaluate the associations of 1- to 10-h moving average (MA) exposures of indoor PM_2.5 and BC with HRV and ABP indices, and to explore whether these associations could be modified by air filtration.

RESULTS

We observed decreases of 34.8% in indoor PM_2.5 and 35.3% in indoor BC concentrations during active filtration. Indoor PM_2.5 and BC exposures were significantly associated with reduced HRV and increased ABP indices, and greater changes were observed during sham filtration. In specific, each 10 μg/m³ increase in indoor PM_2.5 at MA8-h was associated with a significant reduction of 1.34% (95% CI: -2.42, -0.26) in SDNN during sham filtration, compared with a non-significant reduction of 0.81% (95% CI: -6.00, 4.68) during active filtration (P_inter< 0.001). Each 1 μg/m³ increase in indoor BC at MA8-h was associated with a significant increase of 2.41% (95% CI: 0.38, 4.47) in SBP during sham filtration, compared with a non-significant increase of -1.09% (95% CI: -4.06, 1.96) during active filtration (P_inter = 0.135). Nonlinear inverse exposure-response relationships of indoor air pollution exposures with predicted HRV and ABP indices also confirmed some cardiovascular benefits of short-term air filtration intervention.

CONCLUSIONS

Our results suggested that short-term indoor air filtration intervention can be of some cardiovascular benefits in elderly living with high pollution episodes.

The role of air pollution on ST-elevation myocardial infarction: a narrative mini review

ST-elevation myocardial infarction (STEMI) is one of the potential causes of death worldwide. In spite of substantial advances in its diagnosis and treatment, STEMI is still considered as a major public health dilemma in developed and particularly developing countries. One of the triggering factors of STEMI is supposed to be air pollutants like gaseous pollutants including, sulfur dioxide, nitric dioxide, carbon monoxide, ozone and particulate matters (PM) including, PM under 2.5 µm (PM_2.5) and PM under 10 µm (PM₁₀). Air pollution can trigger STEMI with various mechanisms such as increasing inflammatory factors and changing the heart rate or blood viscosity. In this article, we aimed to explore research in the field and discuss the relationship between air pollution and STEMI.

TRPA1 mediates the cardiac effects of acrolein through parasympathetic dominance but also sympathetic modulation in mice

Numerous studies have demonstrated that short-term air pollution exposure causes cardiac autonomic imbalance as measured by heart rate variability (HRV). We previously showed that a single exposure to acrolein, a ubiquitous gaseous component of air pollution, not only causes autonomic imbalance, but also increases arrhythmia through transient receptor potential A1 (TRPA1) cation channels. Thus, the goal of this study was to characterize acrolein-induced autonomic changes in both normal and TRPA1-knockout mice (KO). Conscious, unrestrained C57BL/6 (WT) and KO mice were exposed to 3 ppm acrolein for 3 h. Separate groups were treated with either atenolol (sympathetic blocker), atropine (parasympathetic blocker) or hexamethonium (autonomic neurotransmission blocker), immediately before exposure. Electrocardiogram (ECG) and heart rate (HR) were recorded continuously before, during and after exposure. Exposure to acrolein produced significant increases in standard deviation of normal-to-normal R-R intervals (SDNN), Root Mean Square of the Successive Differences (RMSSD) and Low-Frequency (LF), as well as an increase in arrhythmia in WT mice. Treatment with atenolol reduced this response while atropine enhanced it, and both drugs blocked the acrolein-induced increase in arrhythmia; hexamethonium had no effect. On the other hand, neither acrolein nor any drug had an effect in the KO mice. Thus, acrolein-induced HRV responses appear to be mediated by a combined parasympathetic and sympathetic modulation. KO mice did not demonstrate any increases in HRV with exposure to acrolein. These data demonstrate that the cardiac effects of irritant air pollutants likely involve disruption of homeostatic balance and altered regulation even in healthy animals.

The mechanisms of air pollution and particulate matter in cardiovascular diseases

Clinical and epidemiological studies demonstrate that short- and long-term exposure to air pollution increases mortality due to respiratory and cardiovascular diseases. Given the increased industrialization and the increased sources of pollutants (i.e., cars exhaust emissions, cigarette smoke, industry emissions, burning of fossil fuels, incineration of garbage), air pollution has become a key public health issue to solve. Among pollutants, the particulate matter (PM) is a mixture of solid and liquid particles which differently affects human health depending on their size (i.e., PM₁₀ with a diameter <10 μm reach the lung and PM_2.5 with a diameter <2.5 μm penetrate deeper into the lung). In particular, the acute exposure to PM₁₀ and PM_2.5 increases the rate of cardiovascular deaths. Thus, appropriate interventions to reduce air pollution may promote great benefits to public health by reducing the risk of cardiovascular diseases. Several biological mechanisms have been identified to date which could be responsible for PM-dependent adverse cardiovascular outcomes. Indeed, the exposure to PM₁₀ and PM_2.5 induces sustained oxidative stress and inflammation. PM_2.5 is also able to increase autonomic nervous system activation. Some potential therapeutic approaches have been tested both in pre-clinical and clinical studies, based on the intake of antioxidants from dietary or by pharmacological administration. Studies are still in progress to increase the knowledge of PM activation of intracellular pathways and propose new strategies of intervention.

Effects of Diesel Exhaust on Cardiovascular Function and Oxidative Stress

SIGNIFICANCE

Air pollution is a major global health concern with particulate matter (PM) being especially associated with increases in cardiovascular morbidity and mortality. Diesel exhaust emissions are a particularly rich source of the smallest sizes of PM ("fine" and "ultrafine") in urban environments, and it is these particles that are believed to be the most detrimental to cardiovascular health. Recent Advances: Controlled exposure studies to diesel exhaust in animals and man demonstrate alterations in blood pressure, heart rate, vascular tone, endothelial function, myocardial perfusion, thrombosis, atherogenesis, and plaque stability. Oxidative stress has emerged as a highly plausible pathobiological mechanism by which inhalation of diesel exhaust PM leads to multiple facets of cardiovascular dysfunction.

CRITICAL ISSUES

Diesel exhaust inhalation promotes oxidative stress in several biological compartments that can be directly associated with adverse cardiovascular effects.

FUTURE DIRECTIONS

Further studies with more sensitive and specific in vivo human markers of oxidative stress are required to determine if targeting oxidative stress pathways involved in the actions of diesel exhaust PM could be of therapeutic value. Antioxid. Redox Signal. 28, 819-836.

A Global Perspective on Sulfur Oxide Controls in Coal-Fired Power Plants and Cardiovascular Disease

Sulfur oxides (SO_x), particularly SO₂ emitted by coal-fired power plants, produce long-term risks for cardiovascular disease (CVD). We estimated the relative risks of CVD and ischemic heart disease (IHD) attributable to SO_x emission globally. National SO_x reduction achieved by emissions control systems was defined as the average SO_x reduction percentage weighted by generating capacities of individual plants in a country. We analyzed the relative risk of CVD incidence associated with national SO_x reduction for 13,581 coal-fired power-generating units in 79 countries. A 10% decrease in SO_x emission was associated with 0.28% (males; 95%CI = −0.39%~0.95%) and 1.69% (females; 95%CI = 0.99%~2.38%) lower CVD risk. The effects on IHD were > 2 times stronger among males than females (2.78%, 95%CI = 1.99%~3.57% vs. 1.18%, 95%CI = 0.19%~2.17%). Further, 1.43% (males) and 8.00% (females) of CVD cases were attributable to suboptimal SOx reduction. Thus, enhancing regulations on SO_x emission control represents a target for national and international intervention to prevent CVD.

The contribution of socioeconomic factors to PM2.5 pollution in urban China

PM_2.5 pollution poses severe health risks to urban residents in low and middle-income countries. Existing studies have shown that the problem is affected by multiple socioeconomic factors. However, the relative contribution of these factors is not well understood, which sometimes leads to controversial controlling measures. In this study, we quantified the relative contribution of different socioeconomic factors, including the city size, industrial activities, and residents' activities, to PM_2.5 pollution in urban China between 2014 and 2015 by using structural equation model (SEM). Our results showed that industrial activities contributed more to PM_2.5 pollution than other factors. The city size and residents' activities also had significant impacts on PM_2.5 pollution. The combined influence of all socioeconomic factors could explain between 44% and 48% of variation in PM_2.5 pollution, which indicated the existence of influences from other factors such as weather conditions and outside sources of pollutants. Findings from our study can contribute to a more comprehensive understanding of the socioeconomic causes of PM_2.5 pollution.

Air Pollution and Stroke

The adverse health effects of air pollution have long been recognised; however, there is less awareness that the majority of the morbidity and mortality caused by air pollution is due to its effects on the cardiovascular system. Evidence from epidemiological studies have demonstrated a strong association between air pollution and cardiovascular diseases including stroke. Although the relative risk is small at an individual level, the ubiquitous nature of exposure to air pollution means that the absolute risk at a population level is on a par with "traditional" risk factors for cardiovascular disease. Of particular concern are findings that the strength of this association is stronger in low and middle income countries where air pollution is projected to rise as a result of rapid industrialisation. The underlying biological mechanisms through which air pollutants exert their effect on the vasculature are still an area of intense discussion. A greater understanding of the effect size and mechanisms is necessary to develop effective strategies at individual and policy levels to mitigate the adverse cardiovascular effects of air pollution.

Vascular and cardiac autonomic function and PM2.5 constituents among the elderly: A longitudinal study

BACKGROUND

Although epidemiologic studies have shown an association between the total mass of particulate matter <2.5μm in aerodynamic diameter (PM_2.5) and cardiovascular disease, few studies have examined PM_2.5 constituents associated with vascular and cardiac autonomic dysfunction.

METHODS

In this longitudinal study, we investigated the relationship between PM_2.5 constituents and blood pressure (BP), and markers of the autonomic nervous system. In 466 elderly subjects residing in communities in Seoul, Korea, we examined 16 constituents, seven sources, and total mass concentrations of PM_2.5. We measured the BP, heart rate (HR), and indices of heart rate variability (HRV), such as the standard deviation of normal-to-normal intervals (SDNN), square root of the mean squared differences of successive NN intervals (rMSSD), and two frequency-domain variables (low frequency [LF] and high frequency [HF]). We used linear mixed effects models to assess the association of PM_2.5 constituents and sources with cardiovascular markers.

RESULTS

BP, HR, and rMSSD were associated with concentration of total mass of PM_2.5. For each increase of the interquartile range in PM_2.5 constituents, systolic and diastolic BP, and HR increased by 2.1-3.3mmHg, 1.2-2.3mmHg, and 1.2-1.9bpm, respectively, while the rMSSD, LF, and HF decreased by 8.1-9.3%, 16.6%, and 20.4%, respectively. Particularly, elemental carbon, sulfate, ammonium, lead, and strontium in the PM_2.5 constituents and emissions from oil combustion and incineration were associated with increased BP, HR, and decreased HRV.

CONCLUSIONS

Our results suggest an association between specific PM_2.5 constituents and vascular and cardiac autonomic functions. These findings may provide supportive evidence for developing a pollution reduction plan to prevent cardiovascular diseases.

A Modular Plug-And-Play Sensor System for Urban Air Pollution Monitoring: Design, Implementation and Evaluation

Urban air pollution has caused public concern globally because it seriously affects human life. Modern monitoring systems providing pollution information with high spatio-temporal resolution have been developed to identify personal exposures. However, these systems' hardware specifications and configurations are usually fixed according to the applications. They can be inconvenient to maintain, and difficult to reconfigure and expand with respect to sensing capabilities. This paper aims at tackling these issues by adopting the proposed Modular Sensor System (MSS) architecture and Universal Sensor Interface (USI), and modular design in a sensor node. A compact MSS sensor node is implemented and evaluated. It has expandable sensor modules with plug-and-play feature and supports multiple Wireless Sensor Networks (WSNs). Evaluation results show that MSS sensor nodes can easily fit in different scenarios, adapt to reconfigurations dynamically, and detect low concentration air pollution with high energy efficiency and good data accuracy. We anticipate that the efforts on system maintenance, adaptation, and evolution can be significantly reduced when deploying the system in the field.

Alterations in cardiovascular function by particulate matter in rats using a crossover design

The objective of this study was to investigate associations between cardiovascular effects and urban ambient particle constituents using an in vivo crossover experimental design. Ambient particles were introduced to an exposure chamber for whole-body exposure of WKY rats, where the particulate matter with an aerodynamic diameter of <2.5 μm (PM_2.5) mass concentration, particle number concentration, and black carbon (BC) were monitored. Organic carbon (OC), elemental carbon (EC), and soluble ions of PM_2.5 were determined. In a crossover design, rats were exposed to ambient particles or high-efficiency particle arrestance (HEPA)-filtered control air for 7 days following a 7-day washout interval. The crossover exposure between particles and HEPA-filtered air was repeated 4 times. Radiotelemetric data on blood pressure (BP) [systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP), and mean arterial pressure (MAP)], heart rate (HR), and heart rate viability (HRV) were subsequently obtained during the entire study. Exposure to the PM_2.5 mass concentration was associated with decreases in the SBP, DBP, MAP, and HR (p < 0.05), whereas no significant changes in the BP or HR occurred with the particle number or black carbon. For HRV, the ln 5-min standard deviation of the normal-to-normal (NN) interval (LnSDNN) and the ln root mean square of successive differences in adjacent NN intervals (LnRMSSD) were positively associated with the PM_2.5 mass concentration (p < 0.05). There were no significant effects of the particle number concentration or BC on HRV. Alterations in the HR were associated with OC, EC, Na⁺, Cl^-, and NO₃^-. Cl^- was associated with the DBP, MAP, HR, SDNN, and RMSSD. NO₃^- was correlated with the SBP, MAP, HR, SDNN, and RMSSD. In conclusion, we observed cardiovascular responses to ambient particles in vivo using a crossover design which can reduce animal use in future environmental studies.

Nanomaterials Versus Ambient Ultrafine Particles: An Opportunity to Exchange Toxicology Knowledge

BACKGROUND

A rich body of literature exists that has demonstrated adverse human health effects following exposure to ambient air particulate matter (PM), and there is strong support for an important role of ultrafine (nanosized) particles. At present, relatively few human health or epidemiology data exist for engineered nanomaterials (NMs) despite clear parallels in their physicochemical properties and biological actions in in vitro models.

OBJECTIVES

NMs are available with a range of physicochemical characteristics, which allows a more systematic toxicological analysis. Therefore, the study of ultrafine particles (UFP, <100 nm in diameter) provides an opportunity to identify plausible health effects for NMs, and the study of NMs provides an opportunity to facilitate the understanding of the mechanism of toxicity of UFP.

METHODS

A workshop of experts systematically analyzed the available information and identified 19 key lessons that can facilitate knowledge exchange between these discipline areas.

DISCUSSION

Key lessons range from the availability of specific techniques and standard protocols for physicochemical characterization and toxicology assessment to understanding and defining dose and the molecular mechanisms of toxicity. This review identifies a number of key areas in which additional research prioritization would facilitate both research fields simultaneously.

CONCLUSION

There is now an opportunity to apply knowledge from NM toxicology and use it to better inform PM health risk research and vice versa. https://doi.org/10.1289/EHP424.

Air Pollution and Hospitalization for Acute Myocardial Infarction in China

There is growing interest in the association between ambient air pollution and acute myocardial infarction (AMI). The objective of this study was to explore the association in 14 Chinese cities using a time-stratified case-crossover design. We identified 80,787 hospital admissions for AMI between January 1, 2014 and December 31, 2015 from electronic hospitalization summary reports. Conditional logistic regression was used to estimate the percent changes with 95% confidence intervals (CIs) in AMI admissions in relation to an interquartile range increase in ambient air pollutant concentrations. All analyzed air pollutants, with the exception of ozone, were positively associated with daily AMI admissions on lag2 and lag3 days. An interquartile range increase in particulate matter <10 µm in aerodynamic diameter, sulfur dioxide, nitrogen dioxide, and carbon monoxide concentrations on lag2 day was significantly associated with a 0.8% (95% CI 0.1%, 1.6%), 2.0% (95% CI 1.2%, 2.9%), 2.2% (95% CI 1.4%, 3.1%), and 1.1% (95% CI 0.4%, 1.8%) increase in AMI admissions, respectively. We also observed a significant association in relation to ozone on lag4 day (percent change: 1.3%; 95% CI 0.2%, 2.4%). Subgroup analyses indicated no effect modification of risk by age (≥65 years and <65 years) or gender. In conclusion, this is the first multicity study in China, or even in other developing countries, to report the short-term effects of air pollution on AMI morbidity. Our findings contribute to the limited scientific data on the effects of ambient air pollution on AMI in developing countries.