Effects Of Fine Particulate Matter Research Articles

Acute cardiovascular mortality in communities living near a major airport: mutual effects of fine particulate matter and nitrogen dioxide

BACKGROUND AND AIM: Ambient air pollution is the leading cause of environmental mortality and morbidity worldwide. However, the individual contributions to acute mortality of traffic-related air pollutants such as nitrogen dioxide (NO2) and fine particulate matter (PM2.5) are still debated. METHODS: We conducted a time-stratified case-crossover study for a study population located around Zurich airport in Switzerland, including 24,886 adult cardiovascular deaths from the Swiss National Cohort. We estimated the risk of cause-specific cardiovascular mortality associated with daily NO2 and PM2.5 exposure at home using distributed lag models up to 7 days preceding death, adjusted for daily temperature, acute night-time aircraft noise, firework celebrations, and holidays. RESULTS:Cardiovascular mortality was associated with NO2; whereas the association with PM2.5 disappeared upon adjustment for NO2. The strongest association was observed between NO2 and ischemic stroke (OR = 1.55 per 10µg/m3, 95% CI = 1.20-2.00). Cause-specific analyses showed differences in terms of delayed effect: OR were highest at 1-3 days after exposure for most health outcomes but at lags of 3-5 days for heart failure. Individual and social vulnerabilities to NO2 associated cardiovascular mortality also varied by health outcome, possibly highlighting the role of different behaviours and risk factors in these groups. CONCLUSIONS:This study confirms the association between ambient, as a marker for primary emissions, and acute cardiovascular mortality in a specific setting around a major airport. Future research should further investigate the role of additional air pollutants including ultra-fine particles on cardiovascular disease to inform most efficient control measures. KEYWORDS: Air pollution (traffic-related), cardiovascular diseases

Short-term effect of fine particulate matter on daily mortality: Effect modification by prolonged continuous exposure to high concentration

BACKGROUND AND AIM: Although the evidence for short-term mortality effect is very high, the epidemiological study for the effect of prolonged continuous exposure to high concentration is rare. The aim of this study is to investigate how the size of the mortality effect of PM₂.₅ would be modified when high concentration period persist. METHODS: We used daily mortality counts (non-traumatic all-cause, respiratory, and cardiovascular), simulated daily PM₂.₅ concentrations, measured daily mean temperature and relative humidity data in seven metropolitan cities (Seoul, Busan, Daegu, Incheon, Gwangju, Daejeon, and Ulsan) during 2006 to 2019. Generalized additive models (GAMs) with quasi-Poisson distribution in the seven cities and Random effect meta-analyses for pooling the city-specific effects were used to examine the short-term effects of PM₂.₅ on mortality. To investigate effect modification by prolonged continuous exposure to high concentration(referent level: 35 μg/m³), we applied categorical consecutive day variables to the GAMs as effect modification terms with PM₂.₅ concentration variables. RESULTS:The daily percent changes per 10 μg/m³ of daily PM₂.₅ concentration for all-cause, respiratory, and cardiovascular mortality were 0.31% (95%CI: 0.16 – 0.46, lag 0 model), 0.61% (95%CI: -0.02 – 1.24, lag 0-2 model), 0.37% (95%CI: 0.08 – 0.66, lag 0 model), respectively. In the effect modification model for all-cause mortality applied lag 0-1 PM₂.₅ exposure, the daily percent changes per 10 μg/m³ for first, second and third, and fourth day or more of consecutive days were 1.30% (95%CI: 0.05 – 2.57), 0.18% (95%CI: -0.70 – 1.06), and 1.19% (95%CI: 0.31 – 2.08). This pattern was similar in the models for cardiovascular than respiratory mortality. CONCLUSIONS:We found a greater effect on daily mortality of daily PM₂.₅ exposure when the high concentration day began and the days lasted for more than fourth days with high concentration. KEYWORDS: Air pollution, Short-term exposure, Environmental epidemiology, Mortality

Development of alveolar-capillary-exchange (ACE) chip and its application for assessment of PM2.5-induced toxicity

Although standard two-dimensional (2D) cell culture is an effective tool for cell studies, monolayer cultivation can yield imperfect or misleading information about numerous biological functions. In this study, we developed an alveolar-capillary exchange (ACE) chip aiming to simulate the cellular microenvironment at the alveolar-capillary interface. The ACE chip was designed with two chambers for culturing alveolar epithelial cells and vascular endothelial cells separately, which are separated by a microporous polycarbonate film that allows for the exchange of soluble biomolecules. Using this model, we further tested the toxic effects of fine particulate matter (PM2.5), a form of airborne pollutant known to induce adverse effects on human respiratory system. These effects are largely associated with the ability of PM2.5 to penetrate the alveoli, where it negatively affects the pulmonary function. Our results indicate that alveolar epithelial cells cultured in the ACE chip in solo and coculture with vascular endothelial cells underwent oxidative injury-induced apoptosis mediated via the PEAK-eIF2α signaling pathway of endoplasmic reticulum stress. The use of ACE chip in an alveolar epithelial cell-vascular endothelial cell coculture model revealed cellular vulnerability to PM2.5. Therefore, this chip provides a feasible surrogate approach in vitro for investigating and simulating the cellular microenvironment responses associated with ACE in vivo.

Health risks of PM2.5-bound polycyclic aromatic hydrocarbon (PAH) and heavy metals (PPAH&HM) during the replacement of central heating with urban natural gas in Tianjin, China.

To investigate the health effects of fine particulate matter (≤ 2.5μm in aerodynamic diameter; PM2.5)-bound heavy metals and polycyclic aromatic hydrocarbons (PAHs) before and after the implementation of the Urban Natural Gas Heating Project (UNGHP), the lifetime cancer risks, hazard quotients (HQs) of heavy metals and PAHs were calculated. Seven kinds of heavy metals (Al, As, Cd, Cr, Mn, Ni and Se) and 12 kinds of PAHs including acenaphthylene (ANY), acenaphthene (ANA), fluoranthene (FLT), pyrene (PYR), chrysene (CHR), benz[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DBA), benzo[ghi]perylene (BPE) and indeno[1,2,3-cd]pyrene (IPY) were analyzed and used for the health risk assessments. It was found that HQ of Mn fell from 1.09 in the coal-burning period to 0.72 in the gas-burning period in the suburban area. And lifetime cancer risks of PAHs fell from 35.7 × 10-6 in the coal-burning period to 17.22 × 10-6 in the gas-burning period in the urban area. It could be concluded that, during the gas-burning period, downward trends were observed for the lifetime cancer risks and HQs of most kinds of heavy metals and PAHs in all regions of Tianjin compared to those during the coal-burning period. The UNGHP was effective, and we should also take other measures to control the pollution.

The chemical composition and toxicological effects of fine particulate matter (PM2.5) emitted from different cooking styles

The mass, chemical composition and toxicological properties of fine particulates (PM2.5) emitted from cooking activities in three Hong Kong based restaurants and two simulated cooking experiments were characterized. Extracts from the PM2.5 samples elicited significant biological activities [cell viability, generation of reactive oxygen species (ROS), DNA damage and inflammation effect (TNF-α)] in a dose-dependent manner. The composition of PAHs, oxygenated PAHs (OPAHs) and azaarenes (AZAs) mixtures differed between samples. The concentration ranges of the Σ30PAHs, Σ17OPAHs and Σ4AZAs and Σ7Carbonyls in the samples were 9627–23,452 pg m−3, 503–3700 pg m−3, 33–263 pg m−3 and 158 – 5328 ng m−3, respectively. Cell viability caused by extracts from the samples was positively correlated to the concentration of benzo[a]anthracene, indeno[1,2,3-cd]pyrene and 1,4-naphthoquinone in the PM2.5 extracts. Cellular ROS production (upon exposure to extracts) was positively correlated with the concentrations of PM2.5, decaldehyde, acridine, Σ17OPAHs and 7 individual OPAHs. TNF-α showed significant positive correlations with the concentrations of most chemical species (elemental carbon, 16 individual PAHs including benzo[a]pyrene, Σ30PAHs, SO42−, Ca2+, Ca, Na, K, Ti, Cr, Mn, Fe, Cu and Zn). The concentrations of Al, Ti, Mn, Σ30PAHs and 8 individual PAHs including benzo[a]pyrene in the samples were positively correlated with DNA damage caused by extracts from the samples. This study demonstrates that inhalation of PM2.5 emitted from cooking could result in adverse human health effects.

Adipose-derived stem cells therapy effectively attenuates PM2.5-induced lung injury

BackgroundThe adverse health effects of fine particulate matter (PM2.5) exposure are associated with marked inflammatory responses. Adipose-derived stem cells (ADSCs) have immunosuppressive effects, and ADSC transplantation could attenuate pulmonary fibrosis in different animal disease models. However, whether ADSCs affect PM2.5-induced lung injury has not been investigated.MethodC57BL/6 mice were exposed to PM2.5 every other day via intratracheal instillation for 4 weeks. After that, the mice received tail vein injections of ADSCs every 2 weeks.ResultsADSC transplantation significantly attenuated systemic and pulmonary inflammation, cardiac dysfunction, fibrosis, and cell death in PM2.5-exposed mice. RNA-sequencing results and bioinformatic analysis suggested that the downregulated differentially expressed genes (DEGs) were mainly enriched in inflammatory and immune pathways. Moreover, ADSC transplantation attenuated PM2.5-induced cell apoptosis and pyroptosis in the lungs and hearts.ConclusionADSCs protect against PM2.5-induced adverse health effects through attenuating pulmonary inflammation and cell death. Our findings suggest that ADSC transplantation may be a potential therapeutic approach for severe air pollution-associated diseases.

Effects of maternal exposure to fine particulate matter on birth weight in 16 counties across China: a quantile regression analysis

The adverse effects of air pollution during pregnancy have been studied intensively, but mainly utilizing linear and logistic models, which generally yield little information about how air pollution may change the distribution of birth weight in populations. We aimed to examine the effects of fine particulate matter (PM2.5) on quantiles of birth weight, and if effects were heterogeneous in different populations and regions. We used a prospective cohort study of 196 283 singleton term live births from 16 counties across China during 2014–2018. PM2.5 exposure for full gestation, each trimester and last gestational month were assessed by Inverse Distance Weighting interpolation. Linear and quantile regression were conducted to estimate associations between PM2.5 exposure and mean birth weight, as well as birth weight distribution, with birthweight z-score as the main outcome. Stratified analyses and Cochran Q tests were conducted by maternal and geographical characteristics. Each 10 µg m−3 increase in average PM2.5 over the entire pregnancy was associated with reduced birthweight z-score (−0.010, 95% CI: −0.015, −0.005) and birth weight (−3.21 g, 95% CI: −5.27, −1.15). In quantile regression, more pronounced effects were observed in lower and intermediate quantiles, with a decrease of 0.021 (95% CI: 0.033, 0.009) and 0.009 (95% CI: 0.015, 0.002) in the 5th and 50th quantiles of birthweight z-score, respectively. Additionally, we observed stronger associations among well-educated, migrant and primiparous mothers as well as in coastal areas. Maternal exposure to PM2.5 was associated with reduction in birth weight, especially for those with very low birth weight. Well-educated, migrant and primiparous mothers, as well as births in coastal areas may be more sensitive to PM2.5 in our study population. The results may be relevant to targeted public health interventions to reduce maternal exposure to air pollution.

Improving indoor air quality through an air purifier able to reduce aerosol particulate matter (PM) and volatile organic compounds (VOCs): Experimental results

The adverse effects of fine particulate matter (PM) and many volatile organic compounds (VOCs) on human health are well known. Fine particles are, in fact, those most capable of penetrating in depth into the respiratory system. People spend most of their time indoors where concentrations of some pollutants are sometimes higher than outdoors. Therefore, there is the need to ensure a healthy indoor environment and for this purpose the use of an air purifier can be a valuable aid especially now since it was demonstrated that indoor air quality has a high impact on spreading of viral infections such as that due to SARS-COVID19. In this study, we tested a commercial system that can be used as an air purifier. In particular it was verified its efficiency in reducing concentrations of PM10 (particles with aerodynamic diameter less than 10 μm), PM2.5 (particles with aerodynamic diameter less than 2.5 μm), PM1 (particles with aerodynamic diameter less than 1 μm), and particles number in the range 0.3 μm–10 μm. Furthermore, its capacity in reducing VOCs concentration was also checked. PM measurements were carried out by means of a portable optical particle counter (OPC) instrument simulating the working conditions typical of a household environment. In particular we showed that the tested air purifier significantly reduced both PM10 and PM2.5 by 16.8 and 7.25 times respectively that corresponds to a reduction of about 90% and 80%. A clear reduction of VOCs concentrations was also observed since a decrease of over 50% of these gaseous substances was achieved.

Nutraceuticals with Anti-inflammatory and Anti-oxidant Properties as an Intervention for Reducing the Health Effects of Fine Particulate Matter: Potential and Prospects.

Air pollution, especially particulate matter pollution, adversely affects human health. A growing pool of evidence has emerged which underscores the potential of individual-level nutritional interventions in attenuating the adverse health impact of exposure to PM2.5. Although controlling emission and reducing the overall levels of air pollution remains the ultimate objective globally, the sustainable achievement of such a target and thus consequent protection of human health will require a substantial amount of time and concerted efforts worldwide. In the meantime, smaller-scale individual-level interventions that can counter the inflammatory or oxidative stress effects triggered by exposure to particulate matter may be utilized to ameliorate the health effects of PM2.5 pollution. One such intervention is the incorporation of nutraceuticals in the diet. Here, we present a review of the evidence generated from various in vitro, in vivo and human studies regarding the effects of different anti-inflammatory and antioxidant nutraceuticals in ameliorating the health effects of particulate matter air pollution. The studies discussed in this review suggest that these nutraceuticals, when consumed as a part of the diet or as additional supplementation, can potentially negate the cellular level adverse effects of exposure to particulate pollution. The potential benefits of adopting a non-pharmacological diet-based approach to air pollution-induced disease management have also been discussed. We argue that before a nutraceuticals-based approach can be used for widespread public adoption, further research, especially human clinical trials, is essential to confirm the beneficial action of relevant nutraceuticals and to explore the safe limits of human supplementation and the risk of side effects. Future research should focus on systematically translating bench-based knowledge regarding nutraceuticals gained from in vitro and in vivo studies into clinically usable nutritional guidelines.

Acute effect of particulate matter pollution on hospital admissions for stroke among patients with type 2 diabetes in Beijing, China, from 2014 to 2018

BackgroundThe health effect of particulate matter pollution on stroke has been widely examined; however, the effect among patients with comorbid type 2 diabetes (T2D) in developing countries has remained largely unknown. MethodsA time-series study was conducted to investigate the short-term effect of fine particulate matter (PM2.5) and inhalable particulate matter (PM10) on hospital admissions for stroke among patients with T2D in Beijing, China, from 2014 to 2018. An over-dispersed Poisson generalized additive model was employed to adjust for important covariates, such as weather conditions and long-term and seasonal trends. ResultsA total of 159,298 hospital admissions for stroke comorbid with T2D were reported. Approximately linear exposure-response curves were observed for PM2.5 and PM10 in relation to stroke admissions among T2D patients. A 10 μg/m3 increase in the four-day moving average of PM2.5 and PM10 was associated with 0.14% (95% confidence interval [CI]: 0.05–0.23%) and 0.14% (95% CI: 0.06–0.22%) incremental increases in stroke admissions among T2D patients, respectively. A 10 μg/m3 increase in PM2.5 in the two-day moving average corresponded to a 0.72% (95% CI: 0.02–1.42%) incremental increase in hemorrhagic stroke, and a 10 μg/m3 increase in PM10 in the four-day moving average corresponded to a 0.14% (95% CI: 0.06–0.22%) incremental increase in ischemic stroke. ConclusionsHigh particulate matter might be a risk factor for stroke among patients with T2D. PM2.5 and PM10 have a linear exposure-response relationship with stroke among T2D patients. The study provided evidence of the risk of stroke due to particulate matter pollution among patients with comorbid T2D.

The Combined Effects of Fine Particulate Matter and Temperature on Preterm Birth in Seoul, 2010-2016.

Background: Preterm birth contributes to the morbidity and mortality of newborns and infants. Recent studies have shown that maternal exposure to particulate matter and extreme temperatures results in immune dysfunction, which can induce preterm birth. This study aimed to evaluate the association between fine particulate matter (PM2.5) exposure, temperature, and preterm birth in Seoul, Republic of Korea. Methods: We used 2010–2016 birth data from Seoul, obtained from the Korea National Statistical Office Microdata. PM2.5 concentration data from Seoul were generated through the Community Multiscale Air Quality (CMAQ) model. Seoul temperature data were collected from the Korea Meteorological Administration (KMA). The exposure period of PM2.5 and temperature were divided into the first (TR1), second (TR2), and third (TR3) trimesters of pregnancy. The mean PM2.5 concentration was used in units of ×10 µg/m3 and the mean temperature was divided into four categories based on quartiles. Logistic regression analyses were performed to evaluate the association between PM2.5 exposure and preterm birth, as well as the combined effects of PM2.5 exposure and temperature on preterm birth. Result: In a model that includes three trimesters of PM2.5 and temperature data as exposures, which assumes an interaction between PM2.5 and temperature in each trimester, the risk of preterm birth was positively associated with TR1 PM2.5 exposure among pregnant women exposed to relatively low mean temperatures (<3.4 °C) during TR1 (OR 1.134, 95% CI 1.061–1.213, p < 0.001). Conclusions: When we assumed the interaction between PM2.5 exposure and temperature exposure, PM2.5 exposure during TR1 increased the risk of preterm birth among pregnant women exposed to low temperatures during TR1. Pregnant women should be aware of the risk associated with combined exposure to particulate matter and low temperatures during TR1 to prevent preterm birth.

Seasonal Variations of Fine Particulate Matter and Mortality Rate in Seoul, Korea with a Focus on the Short-Term Impact of Meteorological Extremes on Human Health

Rapid industrialization of Korea’s economy has brought with it environmental pollution that threatens human health. Among various other pollutants, ambient fine particulate matter known to endanger human health often exceeds air quality standards in Seoul, South Korea’s capital. The goal of this research is to find the impact of meteorological extremes and particle levels on human health. The analysis was conducted using hourly air pollutant concentrations, meteorological variables, and the daily mortality from cerebrovascular disease. Results show that the effect of fine particulate matter on mortality from cerebrovascular disease was more noticeable during meteorological extremes. The linkage between extreme weather conditions and mortality was more apparent in winter than in summer. Comprehensive studies of various causes of diseases should be continued to more accurately analyze the effects of fine particulate matter on human health and meteorological extremes, and to further minimize the public health impact of air pollution and meteorological conditions.

You Can’t Run from Air Pollution: The Effect of Fine Particulate Matter on Physical Tasks

A large share of the world’s population is employed in manual labor. This paper estimates the effect of fine particulate matter (PM 2.5) on purely physical tasks analyzing half a million amateur track and field competition results, a setting that allows excluding productivity effects through the cog- nitive channel. Exploiting the panel nature of the data and high dimensional fixed effects, I find that a 10 µg/m3 increase in PM 2.5 reduces performance by 1% of a standard deviation. The effect grows with the duration of effort, indicating that occupations requiring low-intensity and sustained effort may be more affected by air pollution than occupations requiring occasional short but intense bursts of energy.

On the Short-Term Impact of Pollution: The Effect of PM 2.5 on Emergency Room Visits

In this paper, we study the effect of fine particulate matter (PM 2.5) exposure on Emergency Room (ER) visits in Chile. Our identification strategy exploits daily PM 2.5 variation within a hospital-month-year combination. Unlike previous papers, our data allow us to study the impact of high levels of pollution while controlling for avoidance behavior. We find that a one standard deviation increase in PM 2.5 increases respiratory ER visits by 1.4 percent. This effect is positive for all age groups but is stronger for children (less than five years old) and the elderly (more than 65 years old). Moreover, we find that the effects are stronger in geographical areas in which the share of emissions from residential wood burning is more than 75 percent. Finally, our results are robust to instrumenting pollution using wind direction and speed and to controlling for other pollutants.

RELATIONSHIP BETWEEN FINE PARTICULATE MATTER, WEATHER CONDITIONS AND HOSPITALIZATION FOR STROKE AMONG ELDERLY PEOPLE AT SOME HOSPITALS IN DA NANG 2019

Aims: To investigate the effect of fine particulate matter and weather condition on hospitalization of stroke among elderly people in Da Nang. Method: Cross- sectional study was used in this research, retrospective data were collected and analyzed by Stata 14.0. The data included the hospitalization date, diagnostic code I61, I63 (ICD-10) of each hospitalization, and the age and sex of the patient; weather conditions (temperature, humidity, air pressure, wind) and PM 2.5. Result: The number of patients admitted for stroke was 257. Hospital admission rates for ischemic stroke increased with the increases in PM 2.5 and diurnal temperature range or the decrease in humidity. Hospital admission rates for hemorrhagic stroke increased when the diurnal temperature range or the maximum temperature decreased. Conclusion: PM 2.5 levels and weather conditions impacted hospitalization for stroke.

Lagged Association of Ambient Outdoor Air Pollutants with Asthma-Related Emergency Department Visits within the Pittsburgh Region.

Asthma affects millions of people globally and is especially concerning in populations living with poor air quality. This study examines the association of ambient outdoor air pollutants on asthma-related emergency department (ED) visits in children and adults throughout the Pittsburgh region. A time-stratified case-crossover design is used to analyze the lagged effects of fine particulate matter (PM2.5) and gaseous pollutants, e.g., ozone (O3), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) on asthma-related ED visits (n = 6682). Single-, double-, and multi-pollutant models are adjusted for temperature and analyzed using conditional logistic regression. In children, all models show an association between O3 and increased ED visits at lag day 1 (OR: 1.12, 95% CI, 1.03–1.22, p < 0.05) for the double-pollutant model (OR: 1.10, 95% CI: 1.01-1.20, p < 0.01). In adults, the single-pollutant model shows associations between CO and increased ED visits at lag day 5 (OR: 1.13, 95% CI, 1.00–1.28, p < 0.05) and average lag days 0–5 (OR: 1.22, 95% CI: 1.00–1.49, p < 0.05), and for NO2 at lag day 5 (OR: 1.04, 95% CI: 1.00–1.07, p < 0.05). These results show an association between air pollution and asthma morbidity in the Pittsburgh region and underscore the need for mitigation efforts to improve public health outcomes.

Investigating the acute effects of fine particulate matter on stillbirth risk in Ulaanbaatar, Mongolia

Investigating the acute effects of fine particulate matter on stillbirth risk in Ulaanbaatar, MongoliaTemuulen Enebish, Rima Habre, Carrie V. Breton, Nomindelger Tuvshindorj, Gantuya Tumur, David Warburton, Meredith FranklinBackground: Ulaanbaatar city (UB), the capital and the home to half of Mongolia’s total population, has experienced extreme seasonal air pollution in the past two decades with fine particulate matter (PM2.5) levels reaching 500 µg/m3. We investigated whether short-term increase in daily PM2.5 shortly before delivery results in stillbirth in UB between 2010 and 2018.Methods: We collected individual level data on 1570 stillbirths from hospital records (2010-2013) and surveillance database (2014-2018). Ambient air pollution exposure was estimated at residential area of each case using a Random Forest model. We utilized time-stratified case-crossover design to estimate the relative odds of stillbirth per interquartile range (IQR) increase in PM2.5 for different exposure windows of individual and cumulative lags of 2-6 days before delivery. Effect estimates were derived from a conditional logistic regression model and individual level characteristics were analyzed for effect modification.Results: We observed significantly elevated relative odds of stillbirth per IQR increase in PM2.5 3 days (odds ratio [OR]=1.50, 95% confidence interval [CI]=1.06-2.12) and 6 days (OR=1.41, 95% CI=1.00-1.99) before delivery after adjusting for temperature (spline) and PM10. These estimates increased (lag day 3: OR=1.93, 95% CI=1.25-2.98, lag day 6: OR=1.73, 95% CI=1.11-2.68) after restricting the analysis to cold season (Oct-Mar). We saw elevated yet not significant effect estimates for cumulative lag day averages of 2-3 and 2-6 days. When only looking at stillbirths in cold season, relative odds of stillbirth for all lag day averages increased with odds ratio for 2-3 lag day averages reaching 2.03 (95% CI=1.20-3.44).Conclusion: Acute exposure to PM2.5 before delivery may trigger stillbirth.

Assessment of Long-term Fine Particulate Matter Exposure and Its Effect on Cardiovascular Disease in China

Background Investigations on chronic health effects of fine particulate matter (PM2.5) exposure in China are hindered by the lack of continuous ground monitoring. With satellite-driven models to generate spatiotemporally resolved PM2.5 levels, we aimed to estimate long-term PM2.5 concentrations at high spatial resolution (1 km) and assess the risk of cardiovascular diseases associated with long-term exposure to PM2.5 in China. Methods Monthly PM2.5 concentrations in China from 2000 to 2016 were estimated using machine-learning approaches, with the Multi-Angle Implementation of Atmospheric Correction (MAIAC) aerosol optical depth (AOD) as a major predictor. A longitudinal cohort study, the project of Prediction for Atherosclerotic Cardiovascular Disease Risk in China was used, with 116,972 adults included. Follow-up information from 2000 to 2015 was analyzed using a Cox proportional hazards model with time-varying exposures. Results Machine-learning models for PM2.5 estimation performed good with a random cross-validation R2 of 0.93 at the monthly level. For the time period without ground monitoring, prediction R2 were 0.67 at the monthly and 0.80 at the annual levels. For an increase of 10 μg/m3 in annual PM2.5 exposures, the estimated hazard ratios (HRs) for incidence and mortality of cardiovascular disease were 1.251 (95% CI: 1.220-1.283) and 1.164 (95% CI: 1.117-1.213), respectively. Steeper slopes were observed when the concentration-response functions tended to high PM2.5 levels. Conclusions Satellite-based techniques provide a strong support for environmental health studies. Our findings on the chronic health effect of PM2.5 exposure on cardiovascular diseases expand the current knowledge on adverse health effects of severe air pollution and highlight the potential cardiovascular benefits of air quality improvement in highly polluted regions.

Effects of Fine Particulate Matter on Childhood Asthma Exacerbation in the Philadelphia Metropolitan Region

Background: Fine particulate matter air pollution (PM2.5) is a known risk factor for asthma exacerbation. We aimed to describe the local association between PM2.5 and asthma exacerbation in the Philadelphia region, and to evaluate whether the effect is modified by children’s characteristics or other environmental exposures.Methods: We conducted a time-stratified case-crossover study of pediatric asthma exacerbation (age ≤18 years) occurring from 2011-2014, identified through electronic health records (EHR) of the Children’s Hospital of Philadelphia (CHOP) Care Network. Modeled, census-tract level estimates of daily PM2.5 concentrations were acquired from the EPA’s Downscaler model. We applied conditional logistic regression to estimate the association within warm (Apr-Sep) and cold (Oct-Mar) months, with PM2.5 level modeled as a natural cubic spline (3 degrees of freedom), and adjusting for temperature, relative humidity, and holidays. We evaluated unlagged effects (i.e., PM2.5 levels on the same day as the exacerbation) and effects lagged up to 5 days.Results: There were 54,632 asthma exacerbation events during the study period, with the majority occurring among male (60.75%) and black, non-Hispanic (58.99%) children. We found a positive association between PM2.5 and asthma exacerbation in both warm months (odds ratio [OR] comparing 90th to 25th percentile = 1.09, 95% confidence interval [CI]: 1.01-1.18, lag05) and cold months (OR, 90th vs. 25th percentile = 1.08, 95% CI: 1.04-1.12, lag0). During cold months, risk increases started from the lowest pollutant concentrations. Results were robust to multi-pollutant modeling and adjustment for additional covariates, and we found no effect modification by children’s characteristics (e.g., age, race/ethnicity, allergic rhinitis, eczema). During warm months, the PM2.5 effect was higher on days with detected tree pollen.Conclusion: We found a positive association between PM2.5 and asthma exacerbation. Our results suggest that even small reductions in fine particulate matter air pollution may reduce clinical visits for asthma exacerbation.

Effects of fine particulate matter on acute health events during critics episodes: a case crossover study in Medellín-Colombia 2015

During March of 2015, two critics episodes of PM2.5 were observed in Medellín-Colombia (levels over 75 µg/m3: three times the recommended by the World Health Organization, for three days or more). A case- crossover study stratified over time was carried out to establish the effects of these episodes in the use of emergency services for respiratory and cardiovascular events. Conditional logistic regression models were used to estimate the relative risks with 95% confidence intervals. Data of atmospheric conditions, particulate matter and the diagnostics in emergencia services were collected from public environmental information system and the individual records of health service provision. The analysis was made in populations under 5 years old and and adults aged 65 years and over. In under 5 years old population every 10 μg/m³ increase in PM2.5 was associated with increases in the risk percentage of emergency room visits for asthma (2.8%), acute respiratory infection (2.0%) and pneumonia (2.2%) in the same day of exposure, and for acute respiratory infection (3.6%) in the first day of exposure. For adults 65 and older the increase of 10 μg/m³ in PM2.5 were associated to excess risks for emergencies room visits due to COPD complications in the first day of exposure (0.8%), cerebrovascular disease after two days of (7.2%) and acute respiratory infection in the same day of exposure and after seven days of cumulative exposure with increases in risk pecentages of 0.6% and 0.5% respectively.These results confirm clear associations between ambient PM2.5 and negative health effects in respiratory and cardiovascular systems during critc episodes in Colombia