Differential time-lag effects of ambient PM2.5 and PM2.5-bound PAHs on asthma emergency department visits

Lung function benefits of traditional Chinese medicine Qiju granules against fine particulate air pollution exposure: a randomized controlled trial

Introduction

Multiple targets are considered as the causes of ambient fine particulate matter [aerodynamic diameters of < 2.5 μm (PM2.5)] induced lung function injury. Qiju granules are derived from the traditional Chinese medicine (TCM) formula known as Qi-Ju-Di-Huang-Wan (Lycium, Chrysanthemum, and Rehmannia Formula, QJDHW), which has been traditionally used to treat symptoms such as cough with phlegm, dry mouth and throat, and liver heat. This treatment approach involves attenuating inflammation, oxidative stress, and fibrosis response. This study investigated the effects of Qiju granules on protecting lung function against PM2.5 exposure in a clinical trial.

Methods

A randomized, double-blinded, and placebo-controlled trial was performed among 47 healthy college students in Hangzhou, Zhejiang Province in China. The participants were randomly assigned to the Qiju granules group or the control group based on gender. Clinical follow-ups were conducted once every 2 weeks during a total of 4 weeks of intervention. Real-time monitoring of PM2.5 concentrations in the individually exposed participants was carried out. Data on individual characteristics, heart rate (HR), blood pressure (BP), and lung function at baseline and during the follow-ups were collected. The effects of PM2.5 exposure on lung function were assessed within each group using linear mixed-effect models.

Results

In total, 40 eligible participants completed the scheduled follow-ups. The average PM2.5 level was found to be 64.72 μg/m3 during the study period. A significant negative correlation of lung function with PM2.5 exposure concentrations was observed, and a 1-week lag effect was observed. Forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), forced expiratory flow at 75% of forced vital capacity (FVC) (FEF75), forced expiratory flow at 50% of FVC (FEF50), and forced expiratory flow at 25% of FVC (FEF25) were significantly decreased due to PM2.5 exposure in the control group. Small airway function was impaired more seriously than large airway function when PM2.5 exposure concentrations were increased. In the Qiju granules group, the associations between lung function and PM2.5 exposure were much weaker, and no statistical significance was observed.

Conclusion

The results of the study showed that PM2.5 exposure was associated with reduced lung function. Qiju granules could potentially be effective in protecting lung functions from the adverse effects of PM2.5 exposure.

Clinical Trial Registration

identifier: ChiCTR1900021235.

The Influence of Fine Particulate Matter and Cold Weather on Emergency Room Interventions for Childhood Asthma

(1) Background: Children are the most vulnerable to pollution due to their decreased stature, heightened respiratory rate, and frequent outdoor engagement. PM2.5, nitrogen dioxide (NO2), ozone, and cold weather are associated with pediatric asthma. In this study, we investigated the nexus between air pollution, climate factors, and pediatric asthma emergency room visits (ERVs). (2) Method: Pediatric asthma ERV data for healthcare quality from the Taiwanese National Insurance in the Taipei area were obtained from 2015 to 2019. Air pollution and climate factor data were also collected. Poisson regression was employed to determine the relationships with relative risks (RRs). (3) Results: The incidence of pediatric asthma ERVs decreased, with a crude RR of 0.983 (95% CI: 0.98-0.986, p < 0.001). Fine particulate matter (PM2.5) had an adjusted RR of 1.102 (95% CI: 1.037-1.172, p = 0.002) and a 7.7 µg/m3 increase, and air temperature had an adjusted RR of 0.813 (95% CI: 0.745-0.887, p < 0.001) comparing between the highest and lowest quarter air temperature associated with pediatric asthma ERVs. (4) Conclusions: This inquiry underscores the positive associations of PM2.5 and cold weather with pediatric asthma ERVs. The findings could guide the government to establish policies to reduce air pollution and promote children's health.

Ambient PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) associated with pro-thrombotic biomarkers among young healthy adults: A 16 times repeated measurements panel study

Studies have shown that the cardio/cerebrovascular toxicity of ambient PM2.5 is related to its bound polycyclic aromatic hydrocarbons (PAHs). Currently, only a few studies have reported the relationship between PM2.5-bound PAHs and promoted blood coagulation and thrombosis, but there isn't a consistent conclusion. Therefore, we conducted a prospective panel study to investigate the association. Thirty-three young healthy adults participated in sixteen repeated visits from 2014 to 2018 in Tianjin, China. During each visit, three pro-thrombotic biomarkers: ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motif 13), D-dimer and Myeloperoxidase (MPO) were measured. Before each visit, ambient PM2.5 samples were daily collected for one week. Sixteen PAHs were determined using Gas Chromatography-Mass Spectrometer, and the positive matrix factorization (PMF) model was applied to identify the sources. Linear mixed-effects models were fitted to investigate the associations between PM2.5-bound PAHs exposure and the biomarkers. Thirteen time-metrics were defined to identify significant time points of PM2.5-bound PAHs' effects. We observed that the increase of PM2.5-bound PAHs exposure was significantly associated with reduced ADAMTS13, elevated D-dimer and MPO. At lag0, each 5.7 ng/m3 increase in Benzo[j]fluoranthene and per 3.4 ng/m3 increase Dibenz[a,h]anthracene could make a maximum change of -19.08 % in ADAMTS13 and 132.60 % in D-dimer. Additionally, per 16.43 ng/m3 increase in Chrysene could lead to a maximum elevation of 32.14 % in MPO at lag4. The PM2.5-bound PAHs often triggered more significant changes at lag 3,4 and 6. The ambient PM2.5-bound PAHs originated from six sources: coal combustion (43.10 %), biomass combustion (20.77 %), diesel emission (14.78 %), gasoline emission (10.95 %), industrial emission (7.58 %), and cooking emission (2.83 %). The greatest contributors to alterations in ADAMTS13, D-dimer and MPO are industrial emission (-48.43 %), biomass combustion (470.32 %) and diesel emission (13.14 %) at lag4. Our findings indicated that short-term exposure to ambient PM2.5-bound PAHs can induce alterations of pro-thrombotic biomarkers among healthy adults.

Analyzing COVID-19 and Air Pollution Effects on Pediatric Asthma Emergency Room Visits in Taiwan

(1) Background: An asthma exacerbation that is not relieved with medication typically requires an emergency room visit (ERV). The coronavirus disease 2019 (COVID-19) pandemic began in Taiwan in January of 2020. The influence of the COVID-19 pandemic on pediatric ERVs in Taiwan was limited. Our aim was to survey pediatric asthma ERVs in the COVID-19 era; (2) Methods: Data were collected from the health quality database of the Taiwanese National Health Insurance Administration from 2019 to 2021. Air pollution and climatic factors in Taipei were used to evaluate these relationships. Changes in the rates of pediatric asthma ERVs were assessed using logistic regression analysis. Poisson regression was used to evaluate the impact of air pollution and climate change; (3) Results: The rate of pediatric asthma ERVs declined in different areas and at different hospital levels including medical centers, regional and local hospitals. Some air pollutants (particulate matter ≤ 2.5 µm, particulate matter ≤ 10 µm, nitrogen dioxide, and carbon monoxide) reduced during the COVID-19 lockdown. Ozone increased the relative risk (RR) of pediatric asthma ERVs during the COVID-19 period by 1.094 (95% CI: 1.095-1.12) per 1 ppb increase; (4) Conclusions: The rate of pediatric asthma ERVs declined during the COVID-19 pandemic and ozone has harmful effects. Based on these results, the government could reduce the number of pediatric asthma ERVs through healthcare programs, thereby promoting children's health.

Sestrin2/Keap1/Nrf2 pathway regulates mucus hypersecretion in pulmonary epithelium induced by traffic-related PM2.5 and water-soluble extracts

The involvement of fine particulate matter (PM2.5) exposure in the progression of asthma has been extensively discussed in epidemiological and experimental evidence, which aroused widespread attention. Asthma is characterized by mucus hypersecretion. This study investigates the underlying toxic mechanism of traffic-related PM2.5 (TRPM2.5) and water-soluble extracts (WSE) on mucus hypersecretion in the lungs of rats with asthma and 16HBE cells. The ovalbumin-induced rats were administrated by instillation of TRPM2.5 and WSE in the trachea once three days for eight times. The results showed that TRPM2.5 and WSE had an adverse impact on mucus secretion. Specifically, conspicuous mucus stains and increased goblet cells in the bronchial epithelium by PAS staining were found in lung tissues of rats with asthma; MUC5AC gene and protein expression levels in lung tissues of rats with asthma and 16HBE cells were elevated. In addition, TRPM2.5 and WSE triggered oxidative damage via upregulation of malondialdehyde and myeloperoxidase as well as activation of the Sestrin2/Keap1/Nrf2 signaling pathway. Conversely, the knockdown of Sestrin2 effectively inhibited TRPM2.5 and WSE-induced mucus hypersecretion, oxidative stress, and Keap1/Nrf2 signaling pathway and its downstream target gene NQO1. Collectively, it was demonstrated that TRPM2.5 and WSE induced mucus hypersecretion mediated by the Sestrin2/Keap1/Nrf2 pathway.

PM2.5 exposure promotes asthma in aged Brown-Norway rats: Implication of multiomics analysis

Children are disproportionately represented among those who suffer asthma, which is a kind of chronic airway inflammation. Asthma symptoms might worsen when exposed to the air pollutant particulate matter 2.5 (PM2.5). However, it is becoming more prevalent among older adults, with more asthma-related deaths occurring in this pollution than in any other age group, and symptoms caused by asthma can reduce the quality of life of the elderly, whose asthma is underdiagnosed due to physiological factors. Therefore, in an effort to discover a therapy for older asthma during exposure to air pollution, we sought to ascertain the effects of pre-exposure (PA) and persistent exposure (PAP) to PM2.5 in aged asthma rats. In this study, we exposed aged rats to PM2.5 at different times (PA and PAP) and established an ovalbumin-mediated allergic asthma model. The basic process of elderly asthma caused by PM2.5 exposure was investigated by lung function detection, enzyme-linked immunosorbent assay (ELISA), histopathology, cytology, cytokine microarray, untargeted metabolomics, and gut microbiota analysis. Our findings demonstrated that in the PA and PAP groups, exposure to PM2.5 reduced lung function and exacerbated lung tissue damage, with varying degrees of effect on immunoglobulin levels, the findings of a cytological analysis, cytokines, and chemokines. The PA and PAP rats had higher amounts of polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, 2-methylNaphthalene, 1-methylNaphthalene and flourene. Moreover, exposure to PM2.5 at different times showed different effects on plasma metabolism and gut microbiota. Bioinformatics analysis showed a strong correlation between PAHs, cytokines, and gut microbiota, and PAHs may cause metabolic disorders through the gut microbiota. These findings point to a possible mechanism for the development of asthma in older people exposure to PM2.5 that may be related to past interactions between PAHs, cytokines, gut microbiota, and plasma metabolites.

Long-Term Atmosphere Surveillance (2016-2021) of PM2.5-bound Polycyclic Aromatic Hydrocarbons and Health Risk Assessment in Yangtze River Delta, China

Long-term atmospheric quality monitoring of fine particulate matter (PM2.5) and PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) was performed in Wuxi from 2016 to 2021. In total, 504 atmospheric PM2.5 samples were collected, and PM2.5-bound 16 PAHs were detected. The PM2.5 and ∑PAHs level decreased annually from 2016 to 2021, from 64.3 to 34.0 μg/m3 and 5.27 to 4.22 ng/m3, respectively. The benzo[a]pyrene (BaP) levels of 42% of the monitoring days in 2017 exceeded the recommended European Union (EU) health-based standard of 1 ng/m3. Five- and six-ring PAHs were found, including benz[a]anthracene, benzo[k]fluoranthene (Bkf), BaP, and benzo[g,h,i]perylene, which were the dominant components (indicating a prominent petroleum, biomass, and coal combustion contribution) using molecular diagnostic ratios and positive matrix factorization analysis. Moreover, PM2.5 and PAHs were significantly negatively associated with local precipitation over a period of six years. Statistically significant temporal and spatial distribution differences of PM2.5, and ∑PAHs were also found. The toxicity equivalent quotient (TEQ) of total PAHs was 0.70, and the TEQ of BaP (0.178) was the highest, followed by that of Bkf (0.090), dibenz[a,h]anthracene (Dah) (0.048), and indeno[1,2,3-cd]pyrene (0.034). The medians of the incremental lifetime cancer risk for long-term exposure to PAHs were 2.74E-8, 1.98E-8, and 1.71E-7 for children, teenagers, and adults, respectively, indicating that the carcinogenic risk of PAHs pollution in air was acceptable to local residents in this area. Sensitivity analysis revealed that BaP, Bkf, and Dah significantly contributed to carcinogenic toxicity. This research provides comprehensive statistics on the local air persistent organic pollutants profile, helps to identify the principal pollution source and compounds, and contributes to the prevention of regional air pollution.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s12403-023-00572-x.

Monitoring ambient air pollution and pulmonary function in asthmatic children by mobile applications in COVID-19 pandemic

BACKGROUND

Several public health measures were implemented during the COVID-19 pandemic. However, little is known about the real-time assessment of environmental exposure on the pulmonary function of asthmatic children. Therefore, we developed a mobile phone application for capturing real-time day-to-day dynamic changes in ambient air pollution during the pandemic. We aim to explore the change in ambient air pollutants between pre-lockdown, lockdowns, and lockdowns and analyze the association between pollutants and PEF mediated by mite sensitization and seasonal change.

METHOD

A prospective cohort study was conducted among 511 asthmatic children from January 2016 to February 2022. Smartphone-app used to record daily ambient air pollution, particulate matter (PM2.5, PM10) Ozon (O₃), nitrogen dioxide (NO₂), Carbon Monoxide (CO), sulfur dioxide (SO₂), average temperature, and relative humidity, which measured and connected from 77 nearby air monitoring stations by linking to Global Positioning System (GPS)-based software. The outcome of pollutants' effect on peak expiratory flow meter (PEF) and asthma is measured by a smart peak flow meter from each patient or caregiver's phone for real-time assessment.

RESULTS

The lockdown (May 19th, 2021, to July 27th, 2021) was associated with decreased levels of all ambient air pollutants aside from SO₂ after adjusting for 2021. NO₂ and SO₂ were constantly associated with decreased levels of PEF across lag 0 (same day when the PEF was measured), lag 1 (one day before PEF was measured), and lag 2 (two days prior when the PEF was measured. Concentrations of CO were associated with PEF only in children who were sensitized to mites in lag 0, lag 1, and lag 2 in the stratification analysis for a single air pollutant model. Based on the season, spring has a higher association with the decrease of PEF in all pollutant exposure than other seasons.

CONCLUSION

Using our developed smartphone apps, we identified that NO₂, CO, and PM10 were higher at the pre-and post-COVID-19 lockdowns than during the lockdown. Our smartphone apps may help collect personal air pollution data and lung function, especially for asthmatic patients, and may guide protection against asthma attacks. It provides a new model for individualized care in the COVID era and beyond.

Short-Term Exposure Effect of Ambient Fine Particulate Matter, Ozone and Cold Temperature on Emergency Room Visits for Asthma Patients

(1) Background: The acute effects of ozone, cold temperature and particulate matter less than 2.5 μm (PM_2.5) in size related to asthma attacks are well known worldwide. The adverse effects of ozone and cold temperature on asthma morbidity in Taiwan are still inconclusive. (2) Methods: This retrospective study included patients who had asthma emergency room visits (ERVs) from 1 January 2016 to 31 December 2019 in a regional hospital in Taiwan. The short-term negative effects were estimated using Distributed Lag Non-Linear Models (DLNMs) for the relative risks (RRs) of asthma ERVs associated with PM_2.5, ozone and cold temperature exposures within 5 days. (3) Results: There was a significant association between a 10 ppm increase in PM_2.5 exposure and asthma ERVs at a 2-day lag (RR 1.166, 95% confidence interval (C.I.): 1.051-1.294). There was a significant association between ozone and asthma ERVs at a 1-day lag (RR 1.179, 95% C.I.: 1.034-1.345). The ambient temperature in cold weather compared with the temperature of minimum asthma ERV showed an RR of 1.214, 95% C.I.: 1.009-1.252 at a 1-day lag. (4) Conclusions: This study provides evidence that short-term exposure to fine suspended particulates, ozone and inverse temperature is associated with asthma exacerbation.

PM2.5-related DNA methylation and the association with lung function in non-smokers

PM_2.5 exposure leads to lung function alteration. The potential pathway underlying above association, especially the role of DNA methylation is unclear. The objectives of this study are to evaluate the associations of personal PM_2.5 concentrations with DNA methylation at the epigenome-wide level, and investigate how PM_2.5-related DNA methylation affects lung function. A total of 402 observations of non-smokers were selected from the Wuhan-Zhuhai cohort. PM_2.5 exposure was estimated through a model established in the same population. Blood DNA methylation levels were determined through Illumina Infinium MethylationEPIC BeadChips. Lung function was tested through spirometry on the day of blood sampling. The associations of PM_2.5 exposure with DNA methylation and DNA methylation with lung function were determined through linear mixed models. Ten PM_2.5-related CpG sites (mapped to 7 different genes) were observed with false discovery rate <0.05. Methylation levels of cg24821877, cg24862131, cg23530876, cg11149743 and cg10781276 were positively associated with PM_2.5 concentrations. While methylation levels of cg10314909, cg08968107, cg18362281, cg24663971 and cg17834632 were negatively associated with PM_2.5 concentrations. The top CpG was cg24663971 (P = 1.51✕10^-9). Among the above 10 sites, significantly positive associations of methylation levels of cg24663971 with FVC%pred and FEV₁%pred, and cg10314909 with FVC, FVC%pred, and FEV₁%pred were observed. Age had modification effect on the associations between cg24663971 methylation and FVC%pred, and the associations were more obvious among participants with age ≥58 years. In conclusion, PM_2.5 exposure was associated with DNA methylation, and PM_2.5-related DNA methylation was associated with lung function among Wuhan urban non-smokers.

Lagged acute respiratory outcomes among children related to ambient pollutant exposure in a high exposure setting in South Africa

Acute ambient air pollution impacts on the respiratory health of children may be lagged across time. We determined the short-term lagged effects of particulate matter (PM_2.5), sulphur dioxide (SO₂), and oxides of nitrogen (NO_x) on the respiratory health of children living in low-income communities.

METHODS

A school-based study was conducted using a repeated measures design, across summer and winter, in four schools in each of four suburbs in the Vaal Triangle, South Africa. Data for PM_2.5, NO_x, and SO₂ were obtained from monitoring stations within close proximity of the schools. Over 10 school days in each phase, grade 4 children completed a symptoms log and lung function tests. Parents completed a child respiratory questionnaire. Generalized estimation equations models adjusted for covariates of interest in relation to lung function outcomes and air pollutants including lag effects of 1-5 days.

RESULTS

Daily PM_2.5, NO_x, and SO₂ median concentration levels were frequently higher than international standards. Among the 280 child participants (mean age 9 years), the prevalence of symptoms based on probable asthma was 9.6%. There was a consistent increased pollutant-related risk for respiratory symptoms, except for NO_x and shortness of breath. Lung function, associated with pollutant fluctuations across the different lags, was most pronounced for peak expiratory flow rate (PEFR) for PM_2.5 and SO₂. A preceding 5-day average SO₂ exposure had the largest loss (7.5 L/minute) in PEFR.

CONCLUSIONS

Lagged declines in daily lung function and increased odds of having respiratory symptoms were related to increases in PM_2.5 and SO₂ among a school-based sample of children.

Variations in traffic-related polycyclic aromatic hydrocarbons in PM2.5 in Kanazawa, Japan, after the implementation of a new vehicle emission regulation

A three-year sampling campaign was conducted at a roadside air pollution monitoring station in the urban area of Kanazawa, Japan. Due to a new emission regulation, PAHs levels decreased over the sampling campaign, exhibiting values of 706 ± 413 pg/m³ in 2017, 559 ± 384 pg/m³ in 2018, and 473 ± 234 pg/m³ in 2019. In each year, similar seasonal variations in PAHs levels were observed, with higher levels observed in winter and lower levels in summer. Among the PAHs isomer ratios, we observed that the ratio of benzo[b]fluoranthene (BbF) and benzo[k]fluoranthene (BkF), [BbF]/([BbF] + [BkF]), and the ratio of indeno[1,2,3-cd]pyrene (IDP) and benzo[ghi]perylene (BgPe), [IDP]/([BgPe] + [IDP]), showed stability over the sampling campaign and were less affected by the new emission regulation, seasonal variations, and regional characteristics. When using the combined ratio ranges of 0.66 - 0.80 ([BbF]/([BbF] + [BkF]) and 0.26-0.49 ([IDP]/([BgPe] + [IDP]), traffic emissions were clearly distinguished from other PAHs emission sources. Principal component analysis (PCA) and positive matrix factorization (PMF) were also performed to further analyse the characteristics of traffic-related PAHs. Overall, this study affirmed the effectiveness of the new emission regulation in the reduction of PAHs emissions and provided a combined range for identifying PAHs traffic emission sources.

Machine Learning-Based Analyses of the Effects of Various Types of Air Pollutants on Hospital Visits by Asthma Patients

Asthma is a chronic respiratory disorder defined by airway inflammation, chest pains, wheezing, coughing, and difficulty breathing that affects an estimated 300 million individuals globally. Although various studies have shown an association between air pollution and asthma, few studies have used statistical and machine learning algorithms to investigate the effect of each individual air pollutant on asthma. The purpose of this research was to assess the association between air pollutants and the frequency of hospital visits by asthma patients using three analysis methods: linear correlation analyses were performed by Pearson correlation coefficients, and least absolute shrinkage and selection operator (LASSO) and random forest (RF) models were used for machine learning-based analyses to investigate the effect of air pollutants. This research studied asthma patients using the hospital visit database in Seoul, South Korea, collected between 2013 and 2017. The data set included outpatient hospital visits (n = 17,787,982), hospital admissions (n = 215,696), and emergency department visits (n = 85,482). The daily atmospheric environmental information from 2013 to 2017 at 25 locations in Seoul was evaluated. The three analysis models revealed that NO₂ was the most significant pollutant on average in outpatient hospital visits by asthma patients. For example, NO₂ had the greatest impact on outpatient hospital visits, resulting in a positive association (r=0.331). In hospital admissions of asthma patients, CO was the most significant pollutant on average. It was observed that CO exhibited the most positive association with hospital admissions (I = 3.329). Additionally, a significant time lag was found between both NO₂ and CO and outpatient hospital visits and hospital admissions of asthma patients in the linear correlation analysis. In particular, NO₂ and CO were shown to increase hospital admissions at lag 4 in the linear correlation analysis. This study provides evidence that PM_2.5, PM₁₀, NO₂, CO, SO₂, and O₃ are associated with the frequency of hospital visits by asthma patients.

Impact of air pollutants on hospital visits for pediatric asthma in Fuzhou city, southeast China

Rapid social development in China has resulted in severe air pollution and adverse impacts on people's health. Although studies have been conducted on the relationship between exposure to air pollutants and asthma exacerbation, most studies were performed in relatively heavily polluted areas, while little is known about the effect of air pollutants in less polluted areas. We assessed the effects of air pollutants on the risk of asthma-related outpatient and emergency visits of infants and children aged from 0 to 13 years during 2018 to 2020 in Fuzhou city, southeast China. Data of six air pollutants: sulfur dioxide (SO₂), nitrogen dioxides (NO₂), carbon monoxide (CO), daily maximum 8-h average ozone (O₃-8 h), particulate matter with an aerodynamic diameter ≤ 10 μm (PM₁₀), and particulate matter with an aerodynamic diameter ≤ 2.5 μm (PM_2.5), were obtained from the Environmental Protection Administration of Fuzhou. Data of temperature, humidity, and wind speed were provided by the Meteorological Bureau of Fuzhou. Results revealed that on lag day 6, NO₂, SO₂, and CO were positively associated with the number of outpatient and emergency visits. Among the pollutants, SO₂ had the highest effects on both outpatient visits (RR = 1.672, 95%CI 1.545, 1.809) and emergency visits (RR = 1.495, 95%CI 1.241, 1.800), and its effect on outpatient visits was stronger in children aged 0-4 years than in those aged 5-13 years (RR = 2.331 vs. 1.439). In conclusion, SO₂ contributes substantially to the adverse effects of air pollutants on pediatric respiratory health in Fuzhou. Younger children were more affected by air pollution than their older counterparts.

Qianjinweijing Decoction Protects Against Fine Particulate Matter Exposure-mediated Lung Function Disorder

Fine particulate matter (PM_2.5) is well known to impair lung function. Strategies protecting against PM_2.5-exerted lung dysfunction have been less investigated. Qianjinweijing decoction (QJWJ), a decoction of a herbal medicine of natural origin, has been used to treat lung disorders as it inhibits oxidation and inflammation. However, no clinical trial has yet evaluated the role of QJWJ in PM_2.5-induced lung dysfunction. Therefore, we conducted a randomized, double-blind, placebo-controlled trial to assess whether QJWJ provided lung benefits against the adverse effects of PM_2.5 exposure among adults. Eligible participants (n = 65) were recruited and randomized to receive QJWJ decoction (n = 32) or placebo (n = 33) for 4 weeks. The restrictive ventilatory defect (RVD), lung function parameters, and induced sputum were analyzed. The PM_2.5 exposure concentration was significantly associated with the vital capacity (VC), peak expiratory flow (PEF), and forced expiratory flow at 75% of the forced vital capacity (FEF₇₅). The negative associations between PM_2.5 and the lung function parameters were eliminated in response to the QJWJ intervention. Additionally, the percentage of RVD (P = 0.018) and the proportion of eosinophils (Eo%) in induced sputum (P = 0.014) in the QJWJ group was significantly lower than that in the placebo group. This study demonstrated that QJWJ could alleviated PM_2.5-induced lung dysfunction and could be a potential treatment for air pollution-related chronic respiratory disease.

Air pollution and hospital admissions for critical illness in emergency department: a tertiary-center research in Changsha, China, 2016-2020

We aimed to comprehensively investigate the associations of air pollutants with hospital admissions for critical illness in ED. Patients with critical illness including level 1 and level 2 of the Emergency Severity Index admitted in ED of Changsha Central Hospital from January 2016 to December 2020 were enrolled. Meteorological and air pollutants data source were collected from the National Meteorological Science Data Center. A Poisson generalized linear regression combined with a polynomial distributed lag model (PDLM) was utilized to explore the effect of air pollution on hospital admissions for critical illness in ED. Benchmarks as references (25th) were conducted for comparisons with high levels of pollutant concentrations (75th). At first, lagged effects of all different air pollutants were analyzed. Then, based on the most significant factor, analyses in subgroups were performed by gender (male and female), age (< 45, 45-65, and > 65), disorders (cardiovascular, neurological, respiratory), and seasons (spring, summer, autumn, and winter). A total of 47,290 patients with critical illness admitted in ED were included. The effects of air pollutants (PM_2.5, PM₁₀, SO₂, NO₂, O₃ and CO) on critical illness ED visits were statistically significant. Strong collinearity between PM_2.5 and PM₁₀ (r = 0.862) was found. Both single-day lag and cumulative-day lag day models showed that PM_2.5 had the strongest effects (lag 0, RR = 1.025, 95% CI 1.008-1.043, and lag 0-14, RR = 1.067, 95% CI 1.017-1.120, respectively). In both PM_2.5 and PM₁₀, the risks of critical illness in male, > 65 ages, respiratory diseases, and winter increased the most significant. Air pollutants, especially PM_2.5 and PM₁₀ exposure, could increase the risk of critical illness admission.

Effects of PM2.5 on Chronic Airway Diseases: A Review of Research Progress

The adverse effects of polluted air on human health have been increasingly appreciated worldwide. It is estimated that outdoor air pollution is associated with the death of 4.2 million people globally each year. Accumulating epidemiological studies indicate that exposure to ambient fine particulate matter (PM2.5), one of the important air pollutants, significantly contributes to respiratory mortality and morbidity. PM2.5 causes lung damage mainly by inducing inflammatory response and oxidative stress. In this paper, we reviewed the research results of our group on the effects of PM2.5 on chronic obstructive pulmonary disease, asthma, and lung cancer. And recent research progress on epidemiological studies and potential mechanisms were also discussed. Reducing air pollution, although remaining a major challenge, is the best and most effective way to prevent the onset and progression of respiratory diseases.

Does exposure to air pollution increase the risk of acute care in young children with asthma? An Ontario, Canada study

Owing to their greater outdoor activity and ongoing lung development, children are particularly vulnerable to the harmful effects of exposure to fine particulate matter (PM_2.5)_. However, the effects of PM_2.5 components are poorly understood. This study aimed to use a longitudinal birth cohort of children with physician-diagnosed incident asthma to investigate the effect of PM_2.5 components at birth on morbidity measured by health services utilization. Of 1277 Toronto Child Health Evaluation Questionnaire (T-CHEQ) participants, the study population included 362 children diagnosed with asthma who were followed for a mean of 13 years from birth until March 31, 2016, or loss-to-follow-up. Concentrations of PM_2.5 and its components were assigned based on participants' postal codes at birth. Study outcomes included counts of asthma, asthma-related, and all-cause health services use. Poisson regression in single-, two-, and multi-pollutant models was used to estimate rate ratios (RR) per interquartile range (IQR) increase of exposures. Covariates were included in all models to further adjust for potential confounding. The adjusted RR for sulfate (SO₄) and all-cause hospitalizations was statistically significant with RR = 2.23 (95% confidence interval [CI]: 1.25-3.96) in a multi-pollutant model with nitrogen dioxide (NO₂) and ozone (O₃). In multi-pollutant models with oxidants, the adjusted RRs for SO₄ of all-cause hospitalizations and emergency department (ED) visits were also statistically significant with RR = 2.31 (95% CI: 1.32-4.03) and RR = 1.39 (95% CI: 1.02-1.90), respectively. While unadjusted single-pollutant RRs for asthma-specific and asthma-related health services use with the SO₄ component of PM_2.5 were above one, none were statistically significant. This study found significant associations with exposure to SO₄ in PM_2.5 and all-cause acute care, chiefly for hospitalizations, in children with asthma.

Impact of Annual Exposure to Polycyclic Aromatic Hydrocarbons on Acute Exacerbation Frequency in Asthmatic Patients

Purpose

Exposure to polycyclic aromatic hydrocarbons (PAHs) associated with ambient air particulate matter (PM) poses significant health concerns. Increased acute exacerbation (AE) frequency in asthmatic patients has been associated with ambient PAHs, but which subgroup of patients are particularly susceptible to ambient PAHs is uncertain. We developed a new model to simulate grid-scale PM_2.5-PAH levels in order to evaluate whether the severity of asthma as measured by the Global Initiative of Asthma (GINA) levels of treatment is related to cumulative exposure of ambient PAHs.

Methods

Patients with asthma residing in the northern Taiwan were reviewed retrospectively from 2014 to 2017. PM_2.5 were sampled and analysed for PAHs twice a month over a 72-hour period, in addition to collecting the routinely monitored air pollutant data from an established air quality monitoring network. In combination with correlation analysis and principal component analysis, multivariate linear regression models were performed to simulate hourly grid-scale PM_2.5-PAH concentrations (ng/m³). A geographic information system mapping approach with ordinary kriging interpolation method was used to calculate the annual exposure of PAHs (ng/m).

Results

Among the 387 patients with asthma aged 18 to 93 (median 62), 97 subjects were treated as GINA step 5 (24%). Asthmatics in GINA 5 subgroup with high annual PAHs exposure were likely to have a higher annual frequency of any AE (1 (0–12), p<0.0001). Annual PAHs exposure was correlated with the annual frequency of any exacerbation (r=0.11, p=0.02). This was more significant in the GINA 5 subgroup (r=0.29, p=0.005) and in the GINA 5 subgroup with severe acute exacerbations (r=0.51, p=0.002). Annual PAHs exposure, severe acute exacerbation and GINA steps were independent variables that predict annual frequency of any exacerbation.

Conclusion

Asthmatic patients in the GINA 5 subgroup with acute exacerbations were more susceptible to the effect of environmental PAHs on their exacerbation frequency. Reducing environmental levels of PAHs will have the greatest impact on the more severe asthma patients.