Short-term Particulate Matter Exposure Research Articles

Effects of particulate matter exposure on the expression of the SARS-CoV-2 ACE2 receptor in ocular surface tissues and cells.

Particulate matter (PM) has been reported to be one of the risk factor for COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, although the ocular surface is deeply affected by both PM exposure and SARS-COV-2 infection, no studies have investigated the effects of PM exposure on the ocular route of SARS-COV-2 infection. To this end, we explored the effects of PM on the expression of SARS-COV-2-associated receptors and proteins in ocular surface. Herein, short- and long-term PM-exposed rat models were established by topically administering PM for 3 and 10days, respectively. Immortalized human corneal epithelial cells (HCECs) and human conjunctival epithelial cells (HCjECs) were exposed to PM. ACE2, TMPRSS2, CD147, and ADAM17 expression levels were measured by western blot analysis. Our results show that short-term PM exposure had little effect on the expressions of ACE2, TMPRSS2, and CD147 in ocular surface tissues. However, long-term PM exposure decreased the ACE2 expression in conjunctival tissues and increased the CD147 expression in corneal or conjunctival tissues. PM exposure reduced the ACE2 expression by increasing the ADAM17 expression and ACE2 shedding level in HCECs and HCjECs. Our findings suggest that long-term PM exposure down-regulate the expression of the SARS-CoV-2 receptor ACE2 in conjunctival tissues through ADAM17-dependent ACE2 shedding. However, long-term PM exposure up-regulates the expression of another SARS-CoV-2 receptor CD147 in ocular surface tissues, accompanied by ocular surface damage and cytotoxicity. This study provides a new insight into uncovering potential risk factors for infection with SARS-CoV-2 via the ocular route.

The short-term effect of ambient particulate matter on suicide death

BackgroundAir pollution can cause various respiratory and neurological diseases and continuous exposure can lead to death. Previous studies have reported that particulate matter (PM) exposure increases the risk of depression, suicidal thoughts, and suicidal death; however, the results are inconsistent and limited. This study aimed to examine the relationship between short-term PM exposure and suicide deaths, as well as investigate the short-term effects of PM on suicide death within vulnerable groups based on factors such as sex, age group, suicide-related information (note, method, and cause), psychiatric disorders, and physical diseases.MethodsData on a total of 28,670 suicide deaths from 2013 to 2017, provided by the Korea Foundation for Suicide Prevention, were analyzed. The study design employed a time-series analysis with a two-stage approach. In the first step, a generalized additive model combined with a distributed lag nonlinear model was used to estimate the short-term effect of PM exposure on suicide risk specific to each city. In the second step, the estimated results from each city were pooled through a meta-analysis to derive the overall effect. We determined the effects of single lag, cumulative lag, and moving average PM concentrations from days 0–7 before suicide.ResultsWe confirmed an association between exposure to PM10 (≤ 10 μm in diameter) and deaths due to suicide. In particular, among individuals with psychiatric disorders and those who employed non-violent suicide methods, increased exposure to PM10 was associated with a higher risk of death by suicide, with percentage changes of 5.92 (95% confidence interval [CI]: 3.95–7.92) and 11.47 (95% CI: 7.95–15.11), respectively. Furthermore, in the group with psychiatric disorders, there was an observed tendency of increasing suicide risk as PM10 levels increased up to 120 µg/m3, whereas in the group with non-violent suicide deaths, there was a pronounced trend of rapid increase in suicide risk with an increase in PM10 up to 100 µg/m3.ConclusionsThese results show an association between short-term exposure to PM and suicide. Our study adds evidence for the benefits of reducing PM in preventing diseases and improving mental health.

Short-term effects of ambient PM1, PM2.5, and PM10 on internal metal/metalloid profiles in older adults: A distributed lag analysis in China

There is limited evidence linking exposure to ambient particulate matter (PM) with internal doses of metals and metalloids (metal(loid)s). This study aimed to evaluate the effects of short-term exposure to ambient PM on urine metal(loid)s among Chinese older adults. Biological monitoring data of 15 urine metal(loid)s collected in 3, 970 community-dwelling older adults in Fuyang city, Anhui Province, China, from July to September 2018, were utilized. PMs with an aerodynamic diameter ≤ 1 µm (PM1), ≤ 2.5 µm (PM2.5), and ≤ 10 µm (PM10) up to eight days before urine collection were estimated by space–time extremely randomized trees (STET) model. Residential greenness was reflected by Normalized Difference Vegetation Index (NDVI). We used generalized additive model (GAM) combined with distributed lag linear/non-linear models (DLMs/DLNMs) to estimate the associations between short-term PM exposure and urine metal(loid)s. The results suggested that the cumulative exposures to PM1, PM2.5, or PM10 over two days (lag0-1 days) before urine collection were associated with elevated urine metal(loid)s in DLMs, while exhibited linear or “inverted U-shaped” relationships with seven urine metal(loid)s in DLNMs, including Gallium (Ga), Arsenic (As), Aluminum (Al), Magnesium (Mg), Calcium (Ca), Uranium (U), and Barium (Ba). Aforementioned results indicated robust rather than spurious associations between PMs and these seven metal(loid)s. After standardizations for three PMs, PM1 was the greatest contributor to U, PM2.5 made the greatest contributions to Ga, As, Al, and Ba, and PM10 contributed the most to Mg and Ca. Furthermore, the effects of three PMs on urine Ga, As, Al, Mg, Ca, and Ba were reduced when exposed to higher levels of NDVI. Overall, short-term exposures to ambient PMs contribute to elevated urinary metal(loid) levels in older adults, and three PMs exhibit various contributions to different urine metal(loid)s. Moreover, residential greenness may attenuate the effects of PMs on urine metal(loid)s.

Short-term PM exposure and social stress cause pulmonary and cardiac dysfunction

Ambient particulate matter (PM) exposure increases risk for cardiopulmonary health problems which may be exacerbated in a stressful environment. Co-exposure to PM and stress characterizes the experience of many deployed military personnel and first responders but has not been thoroughly investigated. This is especially relevant to military personnel who have been exposed to high PM levels in conjunction with stressful military conflict situations. To understand the mechanisms and time-course of the health consequences following burn pit exposure, we exposed mice to moderate levels of ambient PM less than 2.5 μM in diameter (PM2.5) alone or in combination with psychological stress. We found male mice exposed to PM2.5 alone or in combination with stress had significantly reduced pulmonary function when subjected to methacholine, indicating increased airway hyperreactivity. These mice experienced increased goblet cell hyperplasia in their lungs, with no change in alveolar density. Mice exposed to PM2.5 and/or stress also exhibited reduced cardiac contractility, right ventricular (RV) output, and changes in RV capillary density and cardiac inflammatory markers. Taken together, these data indicate that short-term exposure to PM2.5 with or without stress causes a clear reduction in pulmonary and cardiac function. We believe that this model is well-suited for the study of military and other occupational exposures, and future work will identify potential mechanisms, including the inflammatory progression of these co-exposures.

The History of Air Quality in Utah: A Narrative Review

Utah has a rich history related to air pollution; however, it is not widely known or documented. This is despite air quality being a top issue of public concern for the state’s urban residents and acute episodes that feature some of the world’s worst short-term particulate matter exposure. As we discuss in this narrative review, the relationship between air pollution and the state’s residents has changed over time, as fuel sources shifted from wood to coal to petroleum and natural gas. Air pollution rose in prominence as a public issue in the 1880s as Utah’s urban areas grew. Since then, scientific advances have increased the understanding of air quality impacts on human health, groups of concerned citizens worked to raise public awareness, policy makers enacted legislation to improve air quality, and courts upheld rights to clean air. Utah’s air quality future holds challenges and opportunities and can serve as useful case for other urbanizing regions struggling with air quality concerns. Population growth and changing climate will exacerbate current air quality trends, but economically viable clean energy technologies can be deployed to reduce air pollution, bringing substantial public health and economic benefits to the state’s residents and other settings with similar public health concerns.

Association of short-term particulate matter exposure with suicide death among major depressive disorder patients: a time-stratified case-crossover analysis

There is growing evidence that suggests a potential association between particulate matter (PM) and suicide. However, it is unclear that PM exposure and suicide death among major depressive disorder (MDD) patients, a high-risk group for suicide. We aimed to assess the effect of short-term exposure to PM on the risk of suicide in MDD patients who are at high risk for suicide. We investigated the risk of suicide among 922,062 newly-diagnosed MDD patients from 2004 to 2017 within the Korean National Health Insurance Service (NHIS) database. We identified 3,051 suicide cases from January 1, 2015, to December 31, 2017, within the death statistics database of the Korean National Statistical Office. PMs with aerodynamic diameter less than 2.5 μm (PM2.5), less than 10 μm (PM10), and 2.5–10 μm (PM2.5–10) were considered, which were provided from the National Ambient Air Monitoring System in South Korea. Time-stratified case-crossover analysis was performed to investigate the association of particulate matter exposure to suicide events. The risk of suicide was significantly high upon the high level of exposure to PM2.5, PM2.5–10 (coarse particle) and PM10 on lag 1 (p for trend < 0.05). Short-term exposure to a high level of PM was associated with an elevated risk for suicide among MDD patients. There is a clear dose–response relationship between short-term PM exposures with suicide death among MDD patients. This result will be used as an essential basis for consideration when establishing an air pollution alarm system for reducing adverse health outcomes by PM.

Association between ambient particulate matter (PM2.5/PM10) and first incident ST-elevation myocardial infarction in Suzhou, China

Interests in evaluation of the effect of air pollution and weather conditions on cardiovascular disease have increased. However, the relationship between short-term particulate matter (PM) exposure and first incident ST-elevation myocardial infarction (STEMI) remains unclear. Medical records were collected from December 2013 to December 2016. A total of 1354 patients with first incident STEMI were included. The daily average of air pollution and weather conditions were calculated. In this case-crossover study, conditional logistic regression was performed to assess the association between daily concentrations of PM and first incident STEMI. The daily average of PM2.5 and PM10 were 58.9μg/m3 and 80.2μg/m3, respectively. In this case-crossover study, single-pollutant models showed that each 10μg/m3 increase in PM2.5 was associated with a percent change of 3.36, 95% confidence interval (CI): (1.01-5.77), or in PM10 percent change of 2.1%, 95%CI: (0.2-4.04) for patients with first incident STEMI. The association remained stable after adjusting for ozone (O3). The results from subgroup analysis showed the association slightly enhanced in women, elder patients, patients with history of diabetes, patients without history of smoking, and cold seasons. The p values were not significant between these strata, which may be due to small sample size. This investigation showed that short-term PM exposure associated with first incident STEMI in Suzhou. Given the effect of PM on the first incident STEMI, strategies to decrease PM should be considered.

Ceramide metabolism mediates the impaired glucose homeostasis following short-term black carbon exposure: A targeted lipidomic analysis

BackgroundAmbient particulate matter (PM), especially its carbonaceous composition black carbon (BC) increases cardiometabolic risks, yet the underlying mechanisms are incompletely understood. Ceramides (Cer; a class of sphingolipids) are biological intermediates in glucose metabolism. ObjectivesTo explore whether Cer metabolism mediates impaired glucose homeostasis following short-term PM exposure. MethodsIn a panel study in Beijing, China, 112 participants were followed-up between 2016 and 2017. Targeted lipidomic analyses quantified 26 sphingolipids in 387 plasma samples. Ambient BC and PM with aerodynamic diameter ≤ 2.5 μm (PM2.5) were continuously monitored in a station. We examined the associations of sphingolipid levels with average BC and PM2.5 concentrations 1–14 days before clinical visits using linear mixed-effects models, and explored the mediation effects of sphingolipids on PM-associated fasting blood glucose (FBG) difference using mediation analyses. ResultsIncreased levels of FBG and multiple sphingolipids in Cer metabolic pathways were associated with BC exposure in 1–14-day time window, but not with PM2.5 exposure. For each 10 μg/m3 increase in the average BC concentration 1–14 days before the clinical visits, species in the Cer C24:1 pathway (Cer, dihydroceramide, hexosylceramide, lactosylceramide, and sphingomyelin C24:1) increased in levels ranging from 11.8% (95% confidence interval [CI]: −6.2–33.2) to 48.7% (95% CI: 8.8–103.4), as did the Cer C16:0, C18:0, and C20:0 metabolic pathway species, ranging from 3.2% (95% CI: −5.6–12.9) to 32.4% (95% CI: 7.0–63.8), respectively. The Cer C24:1 metabolic pathway species mediated 6.5–25.5% of the FBG increase associated with BC exposure in 9-day time window. The Cer C16:0, C18:0, and C20:0 metabolic pathway species mediated 5.4–26.2% of the BC-associated FBG difference. Conclusions: In conclusion, Cer metabolism may mediate impaired glucose homeostasis following short-term BC exposure. The current findings are preliminary, which need to be corroborated by further studies.

Aspirin Alleviates Particulate Matter Induced Asymptomatic Orchitis of Mice via Suppression of cGAS-STING Signaling.

As an important source of air pollutant, airborne particulate matter (PM) has become a major threat to public health. Orchitis is characterized by acute or chronic testicular inflammation and is a primary cause of male infertility. Although accumulating evidence indicates that PM exposure is associated with increased male infertility rates, the mechanism by which PM is involved is not well understood. Here, we found that short-term PM exposure activated NF-κB signaling in mouse Leydig cells and testes and leading to asymptomatic orchitis. Analyzing the mitochondrial abundance and cGAMP levels in PM exposed mouse Leydig cells, we found that PM exposure induced mitochondrial injury and mtDNA release, leading to inflammation via the cGAS-STING axis. We also found that aspirin-induced acetylation of cGAS inhibited the inflammation in mice after PM exposure, especially in the testes. Moreover, aspirin pretreatment rescued offspring growth in PM-exposed mice. In summary, our study not only provides evidence that PM-induced asymptomatic orchitis in mice may be amenable to aspirin pre-treatment by acetylating cGAS, but also provides a potential explanation for male infertility caused by air pollutants.

Association of Short-Term Particulate Matter Exposure among 5-Year Cancer Survivors with Incident Cardiovascular Disease: A Time-Stratified Case-Crossover Study.

The association of short-term particulate matter concentration with cardiovascular disease (CVD) among cancer survivors is yet unclear. Using the National Health Insurance Service database from South Korea, the study population consisted of 22,864 5-year cancer survivors with CVD events during the period 2015–2018. Using a time-stratified case-crossover design, each case date (date of incident CVD) was matched with three or four referent dates, resulting in a total of 101,576 case and referent dates. The daily average particulate matter 10 (PM10), 2.5 (PM2.5), and 2.5–10 (PM2.5–10) on the day of case or referent date (lag0), 1–3 days before the case or referent date (lag1, lag2, and lag3), and the mean value 0–3 days before the case or referent date (lag0–3) were determined. Conditional logistic regression was conducted to calculate the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for CVD according to quartiles of PM10, PM2.5, and PM2.5–10. Compared to the 1st (lowest) quartile of lag0–3 PM10, the 4th (highest) quartile of lag0–3 PM10 was associated with higher odds for CVD (aOR 1.13, 95% CI 1.06–1.21). The 4th quartiles of lag1 (aOR 1.12, 95% CI 1.06–1.19), lag2 (aOR 1.09, 95% CI 1.03–1.16), lag3 (aOR 1.06, 95% CI 1.00–1.12), and lag0–3 (aOR 1.11, 95% CI 1.05–1.18) PM2.5 were associated with higher odds for CVD compared to the respective 1st quartiles. Similarly, the 4th quartile of lag0–3 PM2.5–10 was associated with higher CVD events (aOR 1.11, 95% CI 1.03–1.19) compared to the 1st quartile. Short-term exposure to high levels of PM may be associated with increased CVD risk among cancer survivors.

Effects of short-term exposure to particulate matter on emergency department admission and hospitalization for asthma exacerbations in Brescia district

ABSTRACT Background: Rising pollution plays a crucial role in worsening several respiratory diseases. Particulate Matter (PM)-induced asthma exacerbations are one of the most dangerous events. Objectives: To assess the correlation between progressive particulate matter short-term exposure and asthma exacerbations, we investigated the role of PM levels on Emergency Department (ED) admissions and hospitalizations for these events in Brescia, an important industrial city located in northern Italy with high yearly levels of air pollution. Methods: We analyzed 1050 clinical records of ED admissions for suspected asthma exacerbation, starting from January 2014 to December 2017. Daily PM levels were collected from the Environmental Protection Regional Agency. We performed a time-series analysis using a Poisson regression model with single and multiple day-lag. Results were expressed as Relative Risk (RR) and Excess of Relative Risk (ERR) of severe asthma exacerbation over a 10µg/m3 increase in PM10 and PM2.5 concentration. Results: We selected and focused our analysis on 543 admissions for indisputable asthma exacerbation in ED and hospital. The time-series study showed an increase of the RR (CI95%) for asthma exacerbation-related ED admissions of 1.24 with an ERR of 24.2% for PM2.5 at lag0-1 (p < 0.05). We also estimated for PM2.5 a RR (CI95%) of 1.12 with an ERR of 12.5% at lag0-5 (p ≤ 0.05). Again, for PM2.5, an increase of the RR (CI95%) for asthma exacerbation-related hospitalizations of 1.31 with an ERR of 30.7% at lag0-1 (p < 0.05) has been documented. These findings were confirmed and even reinforced considering only the population living in the city. Conclusions: Short-term PM exposure, especially for PM2.5, plays a critical role in inducing asthma exacerbation events leading to ED admission or hospitalization.

Does underweight amplify the relationship between short-term particulate matter exposure and blood pressure in children and adolescents: a large cross-sectional study in a metropolis of China.

Overweight/obesity modified the effects of ambient particulate matter (PM) exposure on blood pressure (BP). This study aims to assess whether interaction of underweight and short-term PM exposure on BP exists in Chinese children. A cross-sectional analysis including 144,513 children aged 6 to 17years in 2016 Health Promotion Program for Children and Adolescents of Suzhou, China, was performed. Daily concentrations of inhalable PM (PM10) and fine PM (PM2.5) were extracted from air monitoring stations close to students' schools. We applied generalized linear mixed-effects models to estimate the interactions. Estimated changes (95% confidence intervals (CIs)) of systolic BP (SBP), diastolic BP (DBP), and odds ratios (ORs) (95% CIs) for prevalence of HBP were calculated. Significant interactions between PM and underweight on BP and prevalence of high BP (HBP) were observed. For example, at lag 6, the ORs (95% CIs) for HBP by each 10μg/m3 changes of PM2.5 were 1.066 (1.039, 1.093) and 1.036 (1.028, 1.043) among underweight and normal weight subjects, respectively; these values for PM10 were 1.048 (1.031, 1.065) and 1.025 (1.021, 1.030). At lag 5, the increases of SBP for PM2.5 were 0.32 (95% CI 0.22, 0.43) mmHg and 0.23 (95% CI 0.29, 0.26) mmHg, while changes of DBP were 0.27 (95% CI 0.18, 0.35) mmHg and 0.19 (95% CI 0.16, 0.21) mmHg among underweight and normal weight subjects, respectively. Stratified analyses demonstrated that these interactions were only obtained in males. Effects of short-term PM exposure on BP and prevalence of HBP are enhanced in underweight children and adolescents.

Sex differences in the interaction of short-term particulate matter exposure and psychosocial stressors on C-reactive protein in a Puerto Rican cohort.

There is substantial evidence linking particulate matter air pollution with cardiovascular morbidity and mortality. However, health disparities between populations may exist due to imprecisely defined non-innate susceptibility factors. Psychosocial stressors are associated with cardiovascular disease and may increase non-innate susceptibility to air-pollution. We investigated whether the association between short-term changes in ambient particulate matter and cardiovascular health risk differed by psychosocial stressors in a Puerto Rican cohort, comparing women and men. We used data from the Boston Puerto Rican Health Study (BPRHS), a longitudinal study of cardiovascular health among adults, collected between 2004 and 2013. We used mixed effect models to estimate the association of current-day ambient particle number concentration (PNC) on C-reactive protein (CRP), a marker of systemic inflammation, and effect modification by psychosocial stressors (depression, acculturation, perceived stress, discrimination, negative life events and a composite score). Point estimates of percent difference in CRP per interquartile range change in PNC varied among women with contrasting levels of stressors: negative life events (15.7% high vs. 6.5% low), depression score (10.6% high vs. 4.6% low) and composite stress score (16.2% high vs. 7.0% low). There were minimal differences among men. For Puerto Rican adults, cardiovascular non-innate susceptibility to adverse effects of ambient particles may be greater for women under high stress. This work contributes to understanding health disparities among minority ethnic populations.

Out-of-hospital cardiac arrests in a large metropolitan area: synergistic effect of exposure to air particulates and high temperature.

Air pollution and climate change are intrinsically linked to emerging hazards for global health. High air particulate matter (PM) levels may trigger out-of-hospital cardiac arrest (OHCA). High temperature could act synergistically with PM in determining OHCA. The aim of the present study was to investigate the effect of PM exposure alone, and in combination with temperature, on the risk of OHCA, in a large European metropolitan area with population >4 million. We evaluated the association between short-term PM exposure, temperature, and the risk of OHCA over a two-year study period, allowing us to investigate 5761 events using a time-stratified case-crossover design combined with a distributed lag non-linear model. Higher risk of OHCA was associated with short-term exposure to PM10. The strongest association was experienced three days before the cardiac event where the estimated change in risk was 1.70% (0.48-2.93%) per 10 µg/m3 of PM. The cumulative exposure risk over the lags 0-6 was 8.5% (0.0-17.9%). We observed a joint effect of PM and temperature in triggering cardiac arrests, with a maximum effect of 14.9% (10.0-20.0%) increase, for high levels of PM before the cardiac event, in the presence of high temperature. The present study helps to clarify the controversial role of PM as OHCA determinant. It also highlights the role of increased temperature as a key factor in triggering cardiac events. This evidence suggests that tackling both air pollution and climate change might have a relevant impact in terms of public health.

A Systematic Review and Meta-Analysis on Short-Term Particulate Matter Exposure and Chronic Obstructive Pulmonary Disease Hospitalizations in China.

We conducted a meta-analysis of short-term particulate matter (PM) exposure and chronic obstructive pulmonary disease (COPD) hospitalizations in China, including data from two-pollutant model. From PubMed and Web of Science, we selected case-crossover or time-series studies conducted in Mainland China, Hong Kong, Macao, or Taiwan to investigate the association between PM exposure and COPD hospitalizations. The meta-analysis was performed using data from both single-pollutant and two-pollutant models for PM2.5 and PM10. A total of 16 studies were included in our analysis. Short-term exposure to PM2.5 and PM10 were both significantly associated with COPD hospitalizations. The results remained robust in two-pollutant model, whereas subgroup analyses demonstrated a modest heterogeneity. Our review shows a small but obvious exposure-hospitalization effect in China. More studies are needed to generate the needed evidence, and advocacy is needed to stimulate initiation of solutions to the problem.

The Effects of Short-Term and Very Short-Term Particulate Matter Exposure on Asthma-Related Hospital Visits: National Health Insurance Data

PurposeThe purpose of this study was to investigate the effects of short-term and very short-term exposure to particulate matter (PM) exceeding the daily average environmental standards for Korea (≤100 µg/m3 for PM10 and ≤50 µg/m3 for PM2.5) on on asthma-related hospital visits.Materials and MethodsThis was a population-based, case-crossover study using National Health Insurance and air pollution data between January 1, 2014 and December 31, 2016. The event day was defined as a day when PM exceeded the daily average environmental standard (short-term exposure) or daily average environmental standard for 2 hours (very short-term exposure). The control day was defined as the same day of the week at 1 week prior to the event day.ResultsCompared with control days, asthma-related hospital visits on the 24-hr event days and 2-hr event days increased by 4.10% and 3.45% for PM10 and 5.66% and 3.74% for PM2.5, respectively. Asthma-related hospital visits increased from the 24-hr event day for PM10 to 4 days after the event day, peaking on the third day after the event day (1.26, 95% confidence interval, 1.22–1.30). Hospitalizations also increased on the third day after the event. While there was a difference in magnitude, PM2.5 exposure showed similar trends to PM10 exposure.ConclusionWe found a significant association between short-term and very short-term PM exposure exceeding the current daily average environmental standards of Korea and asthma-related hospital visits. These results are expected to aid in establishing appropriate environmental standards and relevant policies for PM.

Impact of Particulate Air Pollution on Cardiovascular Health.

Air pollution is established as an independent risk factor for cardiovascular diseases (CVDs). Ambient particulate matter (PM), a principal component of air pollutant, has been considered as a main culprit of the adverse effects of air pollution on human health. Extensive epidemiological and toxicological studies have demonstrated particulate air pollution is positively associated with the development of CVDs. Short-term PM exposure can trigger acute cardiovascular events while long-term exposure over years augments cardiovascular risk to an even greater extent and can reduce life expectancy by a few years. Inhalation of PM affects heart rate variability, blood pressure, vascular tone, blood coagulability, and the progression of atherosclerosis. The potential molecular mechanisms of PM-caused CVDs include direct toxicity to the cardiovascular system or indirect injury by inducing systemic inflammation and oxidative stress in circulation. This review mainly focuses on the acute and chronic effects of ambient PM exposure on the development of cardiovascular diseases and the possible mechanisms for PM-induced increases in cardiovascular morbidity and mortality. Additionally, we summarized some appropriate interventions to attenuate PM air pollution-induced cardiovascular adverse effects, which may promote great benefits to public health.

Short-term particulate matter exposure influences nasal microbiota in a population of healthy subjects

BackgroundExposure to air pollutants, such as particulate matter (PM), represents a growing health problem. The aim of our study was to investigate whether PM could induce a dysbiosis in the nasal microbiota in terms of α-diversity and taxonomic composition. MethodsWe investigated structure and characteristics of the microbiota of 40 healthy subjects through metabarcoding analysis of the V3–V4 regions of the 16s rRNA gene. Exposure to PM10 and PM2.5 was assessed with a personal sampler worn for 24h before sample collection (Day −1) and with measurements from monitoring stations (from Day −2 to Day −7). ResultsWe found an inverse association between PM10 and PM2.5 levels of the 3rd day preceding sampling (Day −3) and α-diversity indices (Chao1, Shannon and PD_whole_tree). Day −3 PM was inversely associated also with the majority of analyzed taxa, except for Moraxella, which showed a positive association. In addition, subjects showed different structural profiles identifying two groups: one characterized by an even community and another widely dominated by the Moraxella genus. ConclusionsOur findings support the role of PM exposure in influencing microbiota and altering the normal homeostasis within the bacterial community. Whether these alterations could have a role in disease development and/or exacerbation needs further research.

Short-term particulate matter exposure induces extracellular vesicle release in overweight subjects

BackgroundExtracellular vesicles (EVs) represent a plausible molecular mechanism linking particulate matter (PM) inhalation to its systemic effects. Microvesicles (MVs) are released from many cell types in response to various stimuli. Increased body mass index (BMI) could modify the response to PM exposure due to enhanced PM uptake and/or an underlying pro-oxidative state.We investigated the relationship between EV release and PM10/PM2.5 exposure in a cohort of 51 volunteers. Subjects were stratified based on their BMI to evaluate whether overweight BMI is a determinant of hypersusceptibility to PM effects. ResultsExposure to PM10/PM2.5 was assessed with a personal sampler worn for 24hours before plasma collection and confirmed with monitoring station data. Size and cellular origin of plasma EVs were characterized by Nanosight analysis and flow cytometry, respectively. Multivariate regression models were run after log-transformation, stratifying subjects based on BMI (≥ or <25kg/m2).PM exposure resulted in increased release of EVs, with the maximum observed effect for endothelial MVs. For PM10 and PM2.5, the adjusted geometric mean ratio and 95% confidence interval were 3.47 (1.30, 9.27) and 3.14 (1.23, 8.02), respectively. Compared to those in normal subjects, PM-induced EV alterations in overweight subjects were more pronounced, with visibly effect in all MV subtypes, particularly endothelial MVs. ConclusionsOur findings emphasize the role of EV release after PM exposure and the susceptibility of overweight subjects. Larger studies with accurate exposure assessment and complete EVs characterization/content analysis, could further clarify the molecular mechanism responsible for PM effects and of hypersusceptibility of overweight subjects.

A Case Crossover Analysis of Out-of-Hospital Cardiac Arrest and Particulate Matter Air Pollution: Investigation of Specific Subgroups

There is increasing evidence of association between particulate matter air pollution and cardiovascular mortality and morbidity. However, the association with the out-of-hospital cardiac arrest (OHCA) event is less clear. We investigated the effects of short-term particulate matter exposure on OHCA especially among specific subgroups. The study included OHCA that occurred in the Nord-Pas-de-Calais region, France, in 2015. A time-stratified case-crossover study design coupled with a conditional logistic regression was used to evaluate the association between OHCA and particle levels of 10 or 2.5 micrometers or less (PM10 or PM2.5 respectively) measured within the hour of the arrest up to 5 days before. Susceptible subgroups by sex, age, diabetes status among OHCA that occurred during non-holiday periods were investigated. In all, 1039 cases were included. Significant associations were found between OHCA during non-holiday periods and PM2.5 and PM10 exposure four days before the arrest and on the day of the arrest. The largest OR were found for the cumulative average twelve hours before the arrest of PM2.5 (OR = 1.17, p = 0.016) and PM10 (OR = 1.33, p < 0.001). With PM2.5, larger OR with smaller p-values were generally obtained within the subgroups of men, age 50 to 75 years old and cases with diabetes. The findings show a significant link between short-term exposure to particulate matter and OHCA during non-holiday periods, with susceptible subgroups to PM2.5 (men, age 50 to 75 years old and diabetics).